CA2681914A1 - Pumping cassette - Google Patents

Abstract

A pump cassette is disclosed. The pump cassette includes a housing having at least one fluid inlet line and at least one fluid outlet line. The cassette also includes at least one reciprocating pressure displacement membrane pump (820) within the housing. The pressure pump pumps a fluid from the fluid inlet line to the fluid outlet line. A hollow spike (902) is also included on the housing as well as at least one metering pump (830). The metering pump (830) is fluidly connected to the hollow spike (902) on the housing and to a metering pump fluid line. The metering pump fluid line is fluidly connected to the fluid outlet line.

Description

Pt! MPl .l~ ~i CA~ ~ ETTE

C:itOSS-RT1 TRENCF. TO RELATED APPI:,t+t_;ATIONS

This applÃc;aticrr.r clain-is the benef:it of:ptitc::r.rt Application Seria( No. :( 1 .'87 1,.680, filed October I?Y 2{}07and crititled Rtmphr.g Cassette which claims priority ftorri tl3~:.
S following United Stttte-s Provisional Patent Applications, all of which are h4r-c,~hy ineorporatedfiere.iti by refer'ezrce in flaciz entÃreties:
U.S. Provisional. Patenf :AppIiÃ:adtrn No, 60..'904,024 entit.led~~emodia1ysi~
System aiid Methods filed on Febrit-ciry 27, 2047i aiid U.S. Provisional Patent Application No. 60:'921,3 14 errtitled. Setis0r .1~~~arattis .10 filed on April 2s ?f}07 boÃ.b o.f'which are herel)3' .incorport3ted by reference in Ãbeir~ e-u.Ã_ireties.
'~~ECH. ti IC:'AL FIELD
`Ã':(~e present irrverrtinn reiates, tcr a pEr.rzrpirig cassette for punip.inM
t`I.t:tid.
SUMMARY Oli !'H-E.lNVENTION
Irz accordance ~vit:li one aspect o.{'Ã:he pornp cassette the cassutt.e int;lu:c~~s a liousirrg 15 havirrg, at least orre fluid irilet lizre and at least f>-tie. tlitid outlet line. 'I'lie cassette alsc~
includes at least OII.C ret:iprocatin= presstti-c displacement membrarte ptt~~~p withiii the }tousrzig. 'Ybe pressure pun3p ptrmps a fluid from Ãtte tlttid itileà lizte to theflulid oxttlet liÃie.
A hollow spike is alsÃ? :irtoluded on the tiotisiiig as well as at least one metering pump, The mete.rirx` pump is f Itiidly connected to the hollow spi:ke on the kiotrsixag z3rrd -to a rneterir~~
20 pLimp fltrid Iiiie. The rneÃeriri;,- pump fluid li~ie is, fluidly conrtected to the fluid outlet li110.
Various eni()oclirrien.Ãs of tl-tis aspect of the cassette include one or morv of the followitig. Where the.t=eciprocating pressure displacement ~tunp iatc::lLides a curved rigid cfa.amber wtkll ai-ic1 a flexible membrane attached to the rig.it{ chamber wail. The flexible mernbrar~e atrd tl-re rigicl clramt-ler wa1l define a pumpi.ag, cllarriber.
Al.so, where the ciissetÃe 25 includes an air vent. f1uiclly c<3ri:srcc-ie-cl to Ã1ie. mc.Ytetirig f.~i.imf.~ fluid linG. W1:ier~,~ the 4ttssette i~IClireIes an air filter connected to thettirr vent. Where the cassette housing iaacl~ides atc:?p plate, a midplare and a bottom plate. Some em1.~odinier7ta fty:rtlrer-iflic,lride crni or more of the ttsi fowj.n,g. A container aitacfiment that includes a contairrer sitppvrt:
device for receiving and maintaining a contairrer anda cassette attachment device fora:ttac.hir3.;
to the spike on 30 the cassotte: The cassette a-[achrnent device includes a. housing arrd.
tteedIG inside th~.a hc>usiz-ig, f1-re rieedle is in fluid cc?ri] mtrzr.ioaÃiocr with the container ; ripport device. Also, wbere the ects;ette further includes at least onÃ.Y valve. In sotUc embodiments, the valves irrclr:rele a valve housi.n4.~ havin~.: a metzibr~iie dividi_ng the housing irito two chambers, an actuatÃon Ã..han~beÃ` and a tiqPiti chamber. In Soiiie embodinient.s, the ktcttiation chamber l-i;:cs at least otic aperture and the liqtiid c[iamber 1ias at:least: oneapcrta:Ãre.
hi some embc3climents, lx-Ã son-leen-lbfaLlirn~,~nt.s of'the valve, the licltiicl clzzimbeY` inc..lcities a substantially snaocaih surface.
In swiie e.alboclialer.rts of the vaIve, the actrtatic.`in chaniber inclttties at least oÃ1e raiscd.
t~eattÃ:re. In some c-i3-ibodiments oE'Ãhc: valve, the vftlve is a volcano vfilve.
In accurdznce witli another aspect of the pÃtnip cassette the cassette incltrdesa 1iotising having zÃ[ least one il.ui~.l .inlet l:ine and at le,~ast oi-ie. il-Lzic.t OMle,'t liire. The cassette also inciricles at least oÃ-ie reciprocating l3re~stu e displacement Ãiicmlarane pun~p witliizi the 1.0 bo-usitag. The preSttÃ.rc pun~~~ pumps a f7tÃitl f:ron>Ã th~.a fltii(i.
ifflct line to the flt,icl o1.Ãt:lit lir.te.
Also, t:lie cassette incitides asecontl: flrzidadministerÃng system within the housing w(iielt includes, a. metering me~intyrane, pump, a second fluid iniet line for pumping a volÃ.Ãnle o# a ~econcl .tlu.id i:nt.o tl-ic fltÃi:cl oLitiet :li~:i-ie, a ho(loNk, spike for fltizd con-amt,Ãnication of the sef:;orzci fluid iÃit:o the second flttid itilet line; and an air vent fltiÃdly coÃinected to theyeccancl flui~.~
1.5 inlet 'e:'arioiis embodiments of this aspect of tlie cassette Ins: ( de oiae or more of t}.ie following. Where the reciprocating przSstÃre. clisplacement ptÃ:~~.~p i.i-ic.ltÃ.des a c:ttrv4tl rigid c.ltait-tber wall aÃid a flexible Ã-ttem4rane a.ttached te) the rigid c:lxaÃii1~er wall. The flexible n~embrasic ~~id the rigiei chamber wall cl.cftne t~ pun-Ãping chamber. Wberc,~
the cassette 20 housing .iucludes a top plate, a zttidplate anda bottom plate.
Irt accordance with. another aspect of the pump cassette the cassette includes a bousanW lzavinp. at least one blood inlet I.inc for pt,mpinw blood -frotr-i a.
patier.it azÃd c3ne blood fiti.tÃlc.t line for pttml.~ing blood to a dia.lyzer. Also, the cassette includes at least two reciprocating presaEZre displacement mcr.nbr~ane ptimp;; wi.tix%n -the housing. The pressure latiir-ips pump tl-ie blood Erom a 1?atiezit: to the dialvrer. The cassette also incliides at least two va1~,e3r the valves inclutliÃag a l-iotiSit}g ariti a mc.Ynnbranc.. The anembr,.ÃÃ~ic div:iLles the housing into two chambers, aÃi actuatiun c_1iambea and a liqtiid chamber. The actuation chamber has at least oÃ:ie aport~~~~ and the liclLaitl charaiber has at least two apurtL,re5, The liclÃ.ticl c.l~~inber iflClirdc.s a substaritiallv smt?otl.a 5tarface. The c.zÃ~settc:. includes a heparin aclanir.~isteri.110 30 system within the housing. .l.hc heparin atlÃiiinistor'ing system inchi.d~.~s a mci3ibran~.~ pump, a 1~epar.i# .Ã inlet IÃnei'or pÃzmFaiaig a volume ot'hepar.in iiito -the blood outlet lizÃe, a hollow spike for fluid connnunicaÃic+n of heparin into t:lie heparÃn inlet liiie, and aai air filter tltiirlly connected to the bel.aarin inlet line for trapping air-Variotis ~~~~~bocii:i-nerits of this aspect of the cassette Ãnclude one, or more of tihe foiiowzng. Where the .reciprocatiziw pressitre displacement puznp includes a curved r.i-6d chamber wall a~-id a flexible inembrane attached to the rigid chamber wall.
The flexible nierribrane Ãrtid tl-ic r.igid chzimber wal.l define a pumpi.ng ctiarnlaer.
Wbere the cassette hotasing inc IttdÃ.s a Ãof.~ plate, a midplate aiid a bottom plate. Wiiere the reciprocating pressure displaCernC111 mc~rnbrane pcimps includes a menibr,inc; riUnpled on at least one sl:irfi:1ce.
These aspects of ti}e irtvertiioÃ~ are not ii1eajit to be exclusive aiicl ot1ier features, asf~ects, andadvai.~ia4:es of the present invention wili be readily apparent t~.~ those of 1.0 ordinary skill in the art wh~.`ri reaci in conjunction with the appundud.
cIa.itris and accom~~auv.iu{w drawings.
BRIEF 13ESCRIl''I'IO\ OF THE Dlt<kW1NGS

These and Ã:gthcr :t-eattar~s and atlvant:~~~s, o~~~ the present inverif:ion will be bet.Ã~.ar l."? u-tiderstood lav reading the ft.illowir~g detailed cieseription., taker-i Ãogetber with the drawi110s wbert.itl.:
FK]. 1A is a sectional view of or7e exemplary embodÃmerit ol`a pod f~~imp that is incorporated iiitc.~ eni~odimerits of the casset:te;
11Ci. I B is a secÃiotizil view of an alternate eint?odiment of pod pump that is 20 incorporated int~ eniE7odÃments of tiio casseÃte;
FlEf. 2.A is an ill-LisÃrative sectional view of ~~~~~ embodiment o-t'one -type of pneumaticai1y controlled valve, that is incorporated itit~.~ some eiiabodi~ia~iits of the cassette;
FIG. 2B is a sectional view of ariotl-ie::r erribo(iimei-it of otte type oi`prieurnatit:a.lly controlled valve that is iÃ3corporated into soÃne eÃnbodiÃnerits of the caSsette;
25 FICi. 2C is a sectional view of another embodiment of otxc type of pn4Liriiziticztlly coaYtrolled valve that is it7corpon, ted iiito some embod.i-MeratS of t.iie cassette:
FI& 2D is a sectional view of another ei3i1aodii3ieiit of one type of pneriniatzc;ally rOT.1trOlleti valve that iS iDCO.rpOrated i11Ã0 s0.111C C.111bocilÃnc:.nts o.i"Ãhe cassetf.e;
FIGS. 2E-2F ar~, top and bottom views ofembodin1ctiÃs of the valving membrane;
}0 FI:E:f. ?G sl.iows pictorial, top aud cross sc;c:ti.ontzl views of one enibc?dianer.rt of the val virt `M meinbrane, 1~'"IGS, 3A and 3B are top tisid section views respectively of a pod pump witbin a casseite:

,,i FIGS, 4A and 4B are pictorial views respectively of a pod pump withirl a cassette having a variable membra:ric;
FI.CfS. 4C and ~D ar-c top and Sect.iori. views respectively of a. pod. pt,anp witl~;ri.n a c.rÃs4eÃte having a dimpIeclivariable merÃibrane;
FIGS, 4EanÃ.i 4F are pictorial vie:ws of a sir~~~le ring membrane witt3 a variable Sixrfac.C;
FIGS. 5A-5D are pictorial views of variotrs embodiments of variable membranes;
FIGS. 5E-51-.1 are p.ic>t.G}riat views of :~axious embodiments ofÃhe,~
metering pump zncinbrane;
1.0 FIGS. 6A and fiB arc pictorial views of a t~.~ci-tzble r'ir3g tnernbrano with a. s:rnooili sr.iz-~ace.
FIGS. 6C and 6D are pictorial views. of a double ring menil?raÃle witli a tl..iinple sa.Ãrface;
FIGS. 6E and 6F are pictorial views of dorrble ring membranes with variat-Ãle 1.5 SÃr:rta.c.cs FIG. tiG is a cross secÃioa~~l view of a double ring .niembrat~e witl~ a var.iabl.esurtac.e;
FICi. 7 is a schematic showing a pressure ;:rc:ttÃaCior~ syster#-i that miÃy be tr.sed to actuate a pod pump-, FIG. 8 is orie embodiment of the fluid flow-pat1i schcmat.ic of the cassett.4t 20 I^tGS. 9A aÃid 913arc isoti-zetric and top views of tk outea-tc~p plate of the exemplary embodiment of the cassctte;
:CIt_iS. 9C arzcl 9DaÃ-e asornctric: and top views of the inr-ier top plate of the ex.em~~la~~, embodiment of the casset:te, FIG. 91., is a side view of t1-re top plate of the cxcmplaÃ-y, cmbocl.imeÃ-Bt o.('t:(-rc casset-te-F1GTS. IOA and lt)B are iscametric aiid top viei~~s of the liquid sie$c ot.'Ãl-ic midplate according to tii~. exerÃipl.ary er~iborlitr-icsit of"Ã.hc cass~.att:cr FIGS. 10t`` and ~OD are iscsrnet-ric and top v.Ãewss of the air side of the midplate according Ãci the cxemp:lav.t cr~ibotl.iriierrt of the casst:tÃc:;
FIG. -I.~"3C is a side vÃew of -he midplate according to the cxc;r~iplary c.anbodiinerit of the 30 oi:1Sst3td:e:
FIGS. l. l.A ar7d 1FB are.isoraietric and top v.iew, of the inner side of the bott:onà plate ~ccording to the cxcrnpIary embodiment of t:lae cassette;

FIGS. .1 lC and 1 lD ar=~.~ isc?metric ariti. tap views of the outer side of the bot:t:oÃ~i. plate acco.rrlin~f io the exemplary e.Ã-r3bcslimer7t oi`t:llc cassette;

FIG. -1 l.lw is a side view of the bottom plate according to t1xÃ;
e:~~rnpleary ~i-irbociimeiit of tl~~ casset-te;
:~IG. .l'?A is a top viow of the assembled e:.lc.Yrnplary Ã.Yrnbodimunt of ÃhÃ.a Ãa~set.iÃ.a wit:li a via1 attachÃ:d4 FIG. 12B is a bottom view ot'the assembled ea;emplary embodiment of the cassette with a vial attached;
FIG. 12C is an exploded view of the assembled exen1plary embodinient of the cassette wit1i zi vial;
FIG. 1'2D is aii exploded view of the assenibled ex,eniplar~~ ~~-iibo~.~iniezià of the cassette 1.0 wit}~ a viat:
FIGS, 13rr"t.-1>C` show cross sectional view% of t:k exemplary embodiment of the assembled cassette;
FIGS, 1.4.A-14:E3 show an asserzibleci alternate embodiment ot`tlae meterirag, purnp;
FIGS. I 4C- I 4D show an explotled. view of tl~e assembleÃi alternate embodiment of the 1.5 metering puml};
FIG. 14E sliow an assembled alternate embodimei.rt of t:hemetering pump cotariected to a t:ass~.~Ctc., FIG. 14F shows a partially assembled alte.rnate, emboÃlime-tit ot't?ie meterizicy pump codlll'.ctt'd to a G=a5setti,.
20 FIGS, 1 5rr"t.-1 5 B show isometric and. top views of outer top plate according to all alternate embocli~iietit of the metering pr.~~~ip_:
CIt_iS. -I'?f;-:t SD show bottom -views o.t`t:tie i~~i-ier top plate acc Ã?rÃlita:w to izl afternate embodiment of the metering pttmp;
FtGS. 16A-16B show .isornetrac and top views of the li.qLti.cl side mi.clpi.a.te according to "."? an alternate embc?ÃIimeizt of the metering puirlp;

:~IGS. -I6(',-1 6D sli.ow isÃ?mÃ:tric-and bottom vie-ws of the air side 111iÃiplatG aciorti:i~ig tc) an alternate embodiment of tl-ie meteriara pi~inp;

FIGS, .1 7A-17B s}iÃaw isoiii~.~tr-ic ariÃ1 top viÃ:-tvs of the inner bottom pla.tÃ.a according to analte.t-natÃ: einboi-i.iment of iliÃ: mÃ:te.rii3g pÃ~iup, 30 FIGS, 17t:'a I 7D show isometric and bottt~~ii views of the out:or bottom according to an alternate enibodiment of the niete.raIW
~ Pia1r.rp, FIGS, I8Aa l8B show isometric~ and top views~.~t otiter top plate according to an aitÃ:rÃiate Ã,rn.laÃgtlir~iont of Ãh~.~ Ã`asse[t:e-, FIGS. 1SC-I SD show bottom views of the inrier top plate according to Rzi-i alternate erzibodinrent of the cassette;

:l; fG. .1 Sfu shows a side view of t1-ic al.t~.ar-n,rte: embodiment of t.lit top p1ate;
FIGS. 19A- 19B show i;yorr~ietx-ic and top views of the liquid side midplate according to an alierirate embodiment of Ãlre cassette;
FIGS. :1 9C:.'- I.9.D show .isi~rnetric and bottona Y i.ews of the air side riiidplate ttccordi.~lo to a:~i aItemate in~~odimeiit of Ã1ic cetssctte;
FIG. 19E shows a side view of tl-ic alternate etatgoclirns~rito1`the naidplate;

FIGS. 2Ã3Ar'_')CtB show isometric arid top views of the hiner bottom pIiate according to 1.0 a1i al1:t'rilate i`rnbCId:Eme1`IC of the cassette;
1^ tGS. ?t3t'-20:D show isoÃ~ietric and bottoÃ~i views of the outer bottom ac:eord.irig to arl alternate embocliriierià of the cassette;
FIG. 2111;? shows a side view of the a1temate embodiment oi'the boitori-a p(zit.e;
1=* IG. 21 A :is a top view of an assembled alternate embodiment of the cassette wit:li a 1.5 vial;
I'IC. 2 113 is a bottcyria view of ari assembled alternate embodiment of the cassette witf-i a FIG. 21t:' is an exploded view ol'tI-te assembled alternate eÃnbodiment ot'tkie cassetÃe with a. vialK
20 1^tG. 2 1:U is ai.~ exploded view of t[ic assembled aalteniate emborlimertt of tfte cassette wit~~ a v:ial;
:CI(iS. 22.A-2213 show c.t-oss sectional views of an alternate enibodinierrt o.f~the assembled c.assÃ.tte;
FIGS. 23A-231:3 show .isonietri.c and top v.iew, of oriter top plate according tn an altemate emboclin-~~tit of the cassette:

:l;fGS. '23f -231) show bottom views o.t"thc.Y i.nrier top plate according to all <zltem'at~.Y
eml=.odimerit of the casset:te.

FIG. 2D1'; shows a side view ol='the alt`:rnat~.a c.Ynil;odirr~ertt of the top pl<rt.Gt FIGS. ?4A-241:~i show .isi~~~ietric and top views of tE:ic liquid si.c'le rrai.dpl.ate at:cordir.rg to 30 an alternate embodiment of'th~.~ tassette.;
FIGS. 24(;-24I3 show isonietric arrcl bottom views of the air sicle midplate accord,irrkf to an atter nat.e ernE7odiniont of the cassette;

FIG. 21.41'; shows a side view ol=''the alt`:t-nat~.a c.Y~~ibodi~~~ertt of the mitlplat:o;

FIGS. 125A-225B show isom~,~tric aii(i top ti~ieNvs of the ii1!.iir bott.ot~.~
f?la.ti.~ acce?rcfiÃig to aÃ~i altez-Ãiate ~intodimerzt of the cassette.

:l;lGS. '25f `-''~51) sli.ow isc?rnetricand bottom views of the outer bottortx ;:Ãcc:orÃling to an alternate c.nibodiÃnent of the t~~~~sette:
FIG. 25E shows a side view of the altc,mate embodiment of the bottoÃ31 f.~la:te;
FIG. ~?6A is a top v.iew of an. as5eÃ~ib(ed alterÃ-Ãt1t.e embodi.ment of'tl~e ctÃssette;
FfG. "6B is a bottom view of an assembled alternate ci3-ibodiÃ31ciit of the cassette:
FIG. 216C is an exp1oiIt.~.l. view of"thu assumblec( alts:rÃ3a.te,~ ei-iibotlimi.'rtt of the e;aSset.te;
FIG. 26D is aÃi exploded view of the asseniblc<d alternate erabs.~ciirne.at of the casse[te;
1.0 aÃicl l^1GS. 27A-27B show cross sectional vi~ws, Ã~fian altemate embr3dinleztt of th.~
assembled cassette.
I)[i."t A.t:Li WD DEWR:t:PTIC}N OFSPEt:'1:E [C: EMBODIMENTS
3 . ['umpiÃ~~g Cassette I.1 C'asSette Tlic parnpi~g ct3ssettz iaic.lÃ7cl.z variotÃ.s #eattÃr~.~s, Ã-Ãame1y, pcxd.
pun-Ãps, fltÃid lzi:-Ães and in some embodÃmeftt, valves. The cassette embod.ÃmentS shown axid described in this tiescriptioii. inclttt.le ixemplary;:Ãncfi some alternate cmbodiments.
However, RkÃ-iy variety of cassettes is coutentpla.tetl that iriclude asimilar hiÃict.Ãoxiality. A~
kvellõ althouglt the cassette embodiments described herein are implementations of the fluid schematics as sliowÃi i11 :CIC=& 8A and 4f3s .iÃÃ other eml=ind:imeÃats, the cas-seit.e niaj, have varyi.Ãa.g tlÃiid paths and:`or ?5 valve place~ieÃit and/or pod ptÃÃnp placc.iiients ~~id nt.tm1.~ers and thris, is still withÃti the scope of the inven.t.i0Ã1.
[a the cxcrriplar~ embodiment, the cassette iÃieludes a top plate, a midplate ~~~-id a boti-c~rn plate. There aro a variety of embodiments for t:a.c.13 plate. t.r.t general, the top plat~.a iticlueles l3cÃ~~~~p chambcrs and l IÃ.iicl lines, tt-ie miclplat:e i.ac.hides coil-ÃplemcÃ-itary tltiid lines, iiietcring puÃ-tips aÃ-id valves aritl the bott.orn falat~.a inctaclis r.tct.uaticstt c.haanb~.ars (and in some eÃnbodirDeDt'S; tl}.e top platt: anc1 the boÃtoni. plate Ins; lude coniplc.aner:Ãtary portions of a balancing i.haII1~.'~er ).
In general, the menitjrar~~s are l.oc.ai~d betweezà t:l-flc mi.clp1aÃ:~ zuid the bot:t:oÃn plate, 1~~~~~ever_ with ~~spcc-t to balancing chambers, a p~.~i-tioÃi of a membraiie is located laetweeÃi.
?5 the mitlplate atZd the top plate. Some oml=,aod.imeÃ-it:s i~ic(-ticli w}iere the rnGanbran~.a is attached to the cassettc; cither ovcÃmo1ded, captu.red, boridecl, press fit, welded in or any other process or method for attachment, however, in the exemplary er-iiboclimcnts, t1le n-ie.mbrailt;s are separate from the top plate, Ãnit113lat:c and bottom plate rÃritil tf-ae plates are asserithled.

Tlic castottcs tiZay be cotist:rticted of a vfrrluN= of i-i3stterials.
C_;on:Grrtlly, in the vari i14 t::mbocliÃxÃent, the rtic-itc:ri{zls tÃ.sed firc ;;olitl stntl non flexible. In the preferred embodiment, the plates are cc.~nstrttcted of pola>stÃ.lfone. but in ottier emliodigr3ents, tht:.
ra4st:ttes are constructed oI'any otl3c:r solid.Ãrtaterirtl and in c:.xcrnplary c.rr:tbc?d.irnent., of aily them-ioplastic or thermosot.
In the exetiiplztrv embot.li_tnerlt, the cassettes are formed by, placing tlti.~ t-iieritbrartes in their correct locations, asscn-iblin4.~ the plates in order aÃid connecting ilie plates. irz oÃie 1.0 t.tnbodi~~ierZt, the plates aro cortrÃecte(i using a laser N-veltlira_g tet:hnirltÃtY, 1lowever, iii other embodi.metrts, the t)latcs mav be alt.ted, rnecharÃ.Ãea(l~~ fa%tened, sirappet.~ tt?iwetlier, ttltrasoriically welded or any other mode of attaching the plates togetlier.
In practice, the cassette rnay be used tt) pttmp attv type oI'-t'ltrid from aÃzy SO'rÃrce to ativ locatioti. The types of fluid inclttt:-le ritit-ritivc, nt?nnÃ.ttritive, inorganic chemicals, 1.5 organic cl.ter.ttÃc:alss bodily fluitls, or aziv otl-ier type of tltaid.
Additionally, fluid in some embodiments include a gas, thus, in 5onie embodimcitts, tlie c.assette, is tised to pttr.r~p a gas.
The cassette serves to ptÃm~ anÃ.1 direct the fltti(l from andtct the desired loc;at.ioti;,. In some embodiments, otatsidc pt.ttt-zps pLÃriip tlie tlrtid itito the cassette aÃiÃ1 the c:assette plimps t(rc fluid ottt. However, in some t,'mbodit1~.:~c.nts, the pod ptÃiiips set-c~e to pull the fltÃict itito 20 the cassette and pt.tnip the fluid out ot'thc c:.assette.
As discussed ibove, depending on the valve locations, cotitrol of the flt.iid paths is irrtpat-tecl. Thus, tl-tc valves beitig an differc:r.Ãt loc.aiions or additional valves z3re a(tcmatc embodiments of this ctt~settr':, Additionally, the t1rÃid lFties and pat.lis shown in the tigttres described above are mere cxart-tples of fl-rÃicl lirte1 and pzitl.ls. Other crrBlaocliri-BCn.ts may ltave ""? ri~tore, less art~ld~r s:liff'ercnt fluid lsaths. In still other emboclii-iic:tits, valves are.not prc5etit: iti, the cassette.
't'he.auriibe.Ã= of pod lstÃmps described above may also vary clepen:cl.ing on. the t.tnbodirrierZt. For exrrrtiplo, altl-iotigh tlrc exe::~-.tip1,trytrt-it.l ~tttÃ.Yrni.tc tinbotliin~.artts slÃc~~vn and described ttboa.e inc.1tt41e; vvo pod pctr.nps, in other embotl.Ãn-Ãcnts, tltc t:assette.Ãstcl.t:Ãdes one.
30 In still other embodiments, the cassette irÃc:it.ttles more tI1aÃ1 two pod pumps. The pod ptÃiiips crtri be sirr-le pt.Frul3s nr- Nvc?rk- in trtYtti:er.t-t to provide a it-zore cor.ttixBt.totÃs .('low. :l::it.lteÃ- or botl}
may be used in variotts eÃiibodimcrits of Ãbe cassette.
The various fluid inlets aaÃ(i tlt.ti.d outlets ttr~.a flt.rld. ports. [n.
practice, depc.rttlirtg t:gÃ;t tl-te valve arrangement ar-icl coÃit,reslj a fILiid ililet caii be a -fluitl otrt:let. 'l'htÃs, the ciesigzlatioÃt of the 1-:lttid port as a fluid inlet or a fluid outlet is cai-~lv for description pttr~~~es. The various er~i.bodirz~ents have interchangeable tluid ports. "I'l1e fluid ports are provided to impart. particular 1:l.iiid paths c?rato the ca.5et:te. Tl-ie:se flaiÃ1 ~.~orÃ:5 art not necessarily all l.is~.a(l all of tl-is; tirne- i11,ste.ad, the variety ut' fil .id ports prcyvides tl.exi~~ifi.ty of use of the cassette 1.Ã1 ~.7ri;1ctIC:e-l.2 ExernpIary Pressure Pod Primp EnibociinieÃit.s, :E716. lA is a sectional view of ar~ exer.i~_~plriry pod ptimp 100 -tl-iat is incorporated into a ~luid cogttrol. or puanp cassette (see, also FIGS. 3 and 4), in accordance wiÃb axi exeniplzs.ry en:tbod.iment of tl-ie cassefte. In this emboalzmeilt, -ttre pod ~~liti, p is -rbrmect.f'rram Ãltree rigid pieces, Ãiamely a "top" plate 106, aÃn.Ãd:plate 1.08, axid a "bottom" plate.140 (it shottld be tioted that the terrns "top" wiÃ.( "bottom" are relative t~~id are ti.sect here for convenience w.ith reference to the oraeÃita.tioÃt s~owta in FIG. I A). The top and bottoÃtl p(zttcs 106 atid 1.10 include generally ~iemispl'ieroid port.ic3iis that when assembled together (.~ del':i~ie a }~~~iii4p}-ieY`oi.d chamber, wlaicb is a pod punljF 1.40.
~~~iembraYie 112 separates the central cavity of the pod ptimp iliÃ~ ~~~o chÃtrn~.~ers.
111 OrIC en-ibod.in~ent, these chambers <~re: the purnping chamber that receives the iluicl to be ptunped. and an actuation chamber for rc..ceivÃiiAp the coir"1 gas that pncumatica.IlyactuaÃes i~~ie puriij). An ifflei !02,all.ows filteid to enter the pumping chamber, and an outlet 104 allows fluid to exit the purnping chamber. The itilet 102 and the out:leÃ.104 Ãtxay be fo~rrtier:t bet.weeii micipIate. 108 aiid ttle top plat.e. 106. Ptie~~tiiat.ic pre:sstire is provided t~~~~ou.~~~ a p~~eurnaÃic port 114 to e.ither force, wiÃb positive gas pres;:tire, the meii1brarie 112 iigai.nst one wall. of pod p~~~~ip cav it~` to n~i~~ir~~iz~: the p~~i~~l~i~a~ ctlari~ber 5vol.um~.~, or to t(raw;wit.h negative Ma:s pressure, the membray-ie 112 towards the other wall of the pod ptrmp 100 cavity to maximize the pumping chamber's vott1me.
I'he r~~embrane I 12 is provided with zi thickened rim116. wkaiclr is held tightly by a protrusion 1:1.8 in the aiidplate 108. Thus, in manufacture, the ziieria:bratie 112 cati be placed iÃi aiitl held by the groove 108 bofore t:1-ie:: bottom plxit.Ã.Y 110 is r:>ois~~ier::t-ecl (in the exeii::tplary embodiment) to tl-te midplaÃe, 108.
Althott(ib not shown in FIGS. l A and I B, in s~.3me 4'm~odimer-its of Ã=h~.~
pod pump, ~i,i the fluid side, a groove is prese'it oii tlae ehaÃnber wall. 'I'kte l-roove acts to prevent fic) lds in the, Ãt3enibra~~e frotii trapping fluid in the chamber when empÃ-vizxg.
Reterri.na tirst to f-1~_'r. IA a cross sectional view of a reciprocating po5iii.ve_ displaceiiieÃià -~~~~~~ip 100 ina cassette is shown. The pod pr.unp 100 includes a flexible mcmbrastc 412 (also Ã=c~~,'rr~,'d to as the :`laL3rnp diaphragtn' or "ii-ÃeÃi-ibraÃÃe.'') mounted where fl-Ãe pLimp.ing el-Ãa.Ãiiber (also re#iv.rred to as a"liqÃ:Ãid chaxrÃber"
o.r"liquid puznping chambtr:r") wall 122 and ttÃe ac[Ã.tat.ion c1-ia.tiZber (also referred to as the "psÃeamr:tf:ic r:.hambGr") wall :1.20 nÃe,;::t. The membrane 14 2 e.{TictÃvc.ly divides that .interio.Ã- cavi.t.v into a vtÃriable-v~olLÃme ~.~ti.iÃirpiÃig chaÃiibcr (Ã.ic.fiÃied by the rigid interior surface of thc l3rÃmpiÃig c,ha:Ã~ber wall 1.22 ~~id a Su.rfZIcC of the .tiÃc:r.rÃbrarÃe 112) fii3d a coÃnplem.c:ntRÃTy va.riable--vc?l-LÃme actuation chamber (defined by the rigid interior surface of the actuation cIraÃii~.~cr wa.11120 aÃ3d a stÃrf;.Ãce oI't.hc rliembÃ4tiaie 112), The top portion 106 itÃclÃ,Ãctes a.1-lLzict iÃÃlet 102 aÃrci a11-ttic1 outlet 104, boti-Ã of wi-ÃiÃ:,b are in tltÃid communication with the pumpixÃg.-IiqÃ:Ãicl c.lÃaÃÃ-Ãber.
1.0 The bottorti portion 111) includes atà actLÃiÃtion or pn~.aÃÃaÃ:1,:Ãt:ic inÃ-erlXÃce 114 in ffiiid communic.ation wiÃh the actuation chamber, As disc rÃssc:cà -ii-a wea:ter dctai( b~.Yic.+w, the membnaxre 11.2 can be tir~ed to move back and tortli wÃtlÃi_Ã:a tl]e ca.vÃty, by a.Itemat:cly zÃpp(y.iÃ.ÃM r~c4.~rrt.i~~e or ~~eÃl t~ tr~ atÃ-z~c~s~~lÃerc aÃi~.
~~~~sit~i~,e l~.ÃxcÃ~rz~x~t-ic pressure at the ~~~.ÃeÃ.~rrz<~.Ãie:
interface 114. As the membrwÃ.c 112 reciprocates back and tbrÃl], tllc sum of the, volumes of 1.5 tlÃe PuMP.iÃ.ÃM rrÃ-Ãd aetÃ.tFrt.ioÃi chambers remains constant.
DiÃriÃtg typical fluid pumping operations, Ãhc< applicatio.n. of'rÃegati~~e or vc-nà to atmrispla~.~r~.~ pneumatic pÃ=cSsÃÃr~.~ to the ac:tr.Ãatitarà or pnctÃ.ÃÃ7aCic interface 11 4 tends to withdraw the ÃiiembraÃte l] 2 toward the actuation chamber wall 120 so as to expand the ptÃrÃ-ÃpingiliqiÃid chamber ai-ici draw tluid into the pÃ,tmpÃÃrg cl:Ãiamber tl:ÃroÃt;rl-à the ÃÃii~.'t 102, 20 while tllc application of positive pzÃctrmatic pressure tends to push the membrazie I.1.2 toward the prcaiipiiiqw chamber wa1l 122 so as t~.~ collapse the purnping c:ha:mber aÃid expel fluid in the pumping c}~arÃ~l~er t}~rc~Ã~4(~ the outlet 104. DÃ.iriÃ~i~~ such ~~Ã.~~ia~.piÃ-Ã4 c~l~e.rz~tic~~.Ãs, the iÃitc..riÃar surfaces ~.~f the pumping chan1ber wall 122 a.ird the actuation chamber wall 120 limit rrÃoverÃicnt of the rricmb.raÃre 4.1.2 as it reciprocates back and fo.rth_ IÃÃ
the erÃlbudi.rncnt "~ s~~t~~~~-tà in :(t lC~. 1 ~~., the iÃÃÃ:eri~.~r surfaces c~f'ttÃe 1~~:ÃÃ~t~l~ÃÃ~~ cha~i-iber ~Nvall '1 22 alid the actrÃaÃi01.Ã
chamber wall 120 aro riaid, sÃ-no<3tfÃ, atÃd fÃc.misptleric:zÃl. In lieu or:t rigi(3 <Ãct-uxÃt-ioÃ14fZat~-.1ber wall 420, arà alternative rigid lirÃiit strrzcÃu.re ------I for ehaÃriple, a portion of zi bezel Liscci for providing prÃcÃ.trtiaÃic prossttr~.~ a:ncfr"or a set o.f"ri.bs - may be used to li:mit tlteinovcnietrt of the menibrttne as the punÃpirÃg c;1~~i-trbc.Ã- approaches maa;.itnutrà value.
Bezels and rib 30 structures are d_escribcd generally in United States I'ateÃ1t ~kp131icatit.~Ãr No, l Ã7'Fi97,~50 eÃÃt:ifled BEZÃ-;.E:. ASSEMBLY I= OÃ~ :PN [-:IJMAI'l(`f: ON'-I'R.()I. filed orà October 30, 2003 a:~~d published as 1~ublicatioiÃ. No. US -'0f.~5/Ã3095 1 ~~ (Att~~~~~cy Docket No. f 062ri`375) and related PCT.ApplicaÃiÃ.grà No. PCT US''t"t04/03595? ei-it.atier~ BEZEL
ASSi=;MR[:.Y FOR.
I'NIElJ MA-I'fC C 'ON-f'RO1, filed ozà October 29, 2004 and f3Ã.ibl.ishec.~
as:pÃabl.ic.ation No. WO

?005;044435 (Attorney Docket No. 1062~1)71WO),. both Ãa1`wbic:h ar4hereby incorporated hereizi. bv reference in their cnlireties. Thus, the rigid lim.it strris Ãuae Suc1i as the rigid aÃ:ttiat:iott Ã;1~~iiZbor wall 120, a bezel, or a s`:t o1=`rib5 - defines the shape of t:l~e mernbr<tne 112 when tliÃ: purripin<j chamber i4 ai its ni<rximÃim I:r.ia pi.-Ã:ferTeÃ1 c:zt.lbÃ?d.ialrÃ:rit., t1ic membrani:. 112 (when Ãirgc:d against the rigiÃ11ii1iit st~.-tiÃ:tt:tre) and the rigid interior surface of tllC Pil.t-11p.ir.Ig c:l-ia~~ibÃ;r wzrll 122 dc{:niÃ: fi spherical pumping Ã:lt.anibez- vÃalur3-ae wheÃl. the ptunping chamber volctt~ie is at a inininittm.
T(itis, in the embodiment slioNvti in FIG, 1A, mÃavetric.i3t. of the mÃ:mbr~ie 1I2 is IUnateel by the puinl3ing cltazYibcr wall .1Ã.22 and the actuation chamber wall 120- As l~.~tt- as 1.0 the positive atZd verit to annos1.-~hÃ:re or ziÃ:g<tÃ.iv~.a prr;:ssuriz:ation51.~rrÃsviÃleÃi through the ~iwinnaÃic port 114 are st.t-oj~~ enotiolt, the mem13rane.112 will.move from a positi~.-~tt limited bv the ac.tuatiogt f:.ltaniber wall 1.20 to a 1aositioÃi lirait:eÃl by tlie 1yrampim, chamber wall 122.
W17eia t(-io menibrane 112 is f:oYced against the actuation ci-iari-alaer wall 120, -11re membrane attel the pumping chamber wall 122 define the riiaximum voItatia.e o1'`tlie pumpittg: chamber, 1.5 WN-ieri tlic: rncmbrane isforc.ed a-;ainst the pEirzipitr- Ã:harlil~er wall 122, the pilrzip.ir:ig Cl1aÃi1l7er is at iÃs m1It1t11#.wti11 vt3lui2]e, In an exemplaty embodiment, the pui-rrpi~~g chamber wall 122 and the at:tttat:ic3ai c:ltantber wall 120 both I-aati~e a ltemisphezo.id. shape so that tli~
puirtpittg chamber w:i1113ave a SpberoiÃl sbape when it is at its maxiinum, voltime. By' asin;= a pt~~i-il?i.r-ig chamber that attains 20 a sptzeroiÃl sÃtape ------aÃ-tÃl particularly a spherical shape ------at maximum volrflttxe, e.ircLilati~~~~~
flow maN= be attained throughout tlze pumping cliaiiit~er. Sric.li shipes accordingly tend to avoid stagnant pockets nI'fltaicl in the pumpi.a4 c.1:~amber. M discussed tiurl:la~~.~r below, the (iriciitatiÃ.~rrs of the irilet 102 and outlet 104 also tÃ>i1Ãl to have an impact oflr the flow of fluid through tl-aC PifMPiDg e1-iEtvtilser and in scsriic_ ei-nboclinicn1s. reducc the likelihood of stagraarat "."? pockets offluid tornrirrg. Additionally, compared t:Ã? other volrt.Ã-nctric sbzipes, the 5pheric:al s1iapt. (,mÃl spheroid shapes in gesrcra:1) tÃ`aicls to create tess,.shÃ.Yar ariÃl turbulence as the #7aiÃl circulates irito, throLigh, atiÃ1 catit of t:lie p1~rnpi.ag, cllar;-lber.

.Re:ii`tring riow to FIGS. 3.A-4Bq a raised flow path 30 is s,howal in the purnping, Ã:Iiaiizbc.r- This raisecl fltaw path 30 fill.ows.t`or the fluid to Ã:Ãsriti.nue flow i.-ta through the l}oÃl 30 ptu~p-s after the menibran~.~ reaches the end of stroke. Tlitis, tltÃ;
raisiÃl. flow patli 30 11.1ininlizes the Chance4 of the rnembrane Ã:aÃisin- air or fluid t:o be 1-rappetl in the pod ptitiip or tlie menibragte bloclw.-i~ig the inlet or otrtlet of the pod punip which wotiicl irt}itlait:
continuous flow. Further description of the raised flow 1.~at1i. is 5boavn and described below with respect to :ftI(IS. 9A-913 aircl FiC'JS. 18A.-18E, "1:`he raised t`1ow paÃ_li 30 is s}~owri in the exemplary embodiment 1iaviiig particular dim~,'Ã-Ãsions, however, in alterÃiate embodiments, as sceri in FIGS, 1S.'3,- 1SE, the raised flow piith 30.Ãs rlarr~~N-er, or idi still other embodiments, the raised flow l?at.li 30 can be a.ny dimensions as the purpcjs~.a is to control tliritl flow ~so as Ãoac;hie;ve c-i desired flow rate or behavior oi:"thc:
fl.l:Ãitl. TIÃu.'s, the dimensions shown and d_i:scribed here with respect t~.~ the raised flow path, the pod ptÃmps, tllc: valves or aÃ-iy other aspect aY`e nÃere exer.n ~~Iarti% ~ÃÃÃc~ ~zlt~:~Ã:Ãatc er:Ãi.l~ocli.tai.c.a~ts. Other ~:r3-a~at~cliri7~.Ã~ts are readily apparent.
TlÃus, fcir exaiiÃp1e, wbcÃi tlre I-Iteiti bsõYi~ig launiped is wtiole blood., ceÃttrifttgzti ptÃmps (which ~ipplv a iYrcat deal of stress oÃa Ãhe rc:d blood cells) caÃi cause a 1arge amount of 1.0 bernolysi.s aÃitl to the detriment of the la<itienÃ.., avlierea:: pod pi.Ãmp5 of the types described above twhichapp:(y low shear i'orc~saÃld trÃ~bulence1 tend to produce sul,istaritially lower }~~rnol~si:~. Si~~~ii~:r[~~, ~~~lierà the fluid l~cin~ pumped is a Srirfactant or other tltiicl prone to fba.Ãn.iÃ.ÃM, tlÃe reclÃic.ed shear forces airrl reduced turbulence of the pod pÃrmps terÃd to reduce t'oamiÃlg.
1.5 Generally speaking, fo.r low s:liear widrfor low iÃ.Ãrbatence applications. it is desirriblc for t;li.e iÃilet a.Ãid oiiÃ:(et to be config),ur~~ ~oas to avoi.d sharp or abrupt changes of fi'ltÃid diret:tioÃi.. It is also generally tiesirablc fior the ii-ilct and outlet (and the l?tÃa3ip c>ha:Ãriber it.~e1f) to be free of flash or bLÃrrs. The inlet aÃld/or otitlet may -irac(ude rouzir:terl edges to help smooth out fluici flow. However, alt}Ãoiigli this benefit has bectx cleScribQcl with respect to 20 whole blood, this was oilly for exan.7ple, the cassette pumps any flui~ and t'(ie beiiefits described with respect to shear sensitive fluids ~.~rl:Ãiological fILÃi~s ma-v apply to catlicr flttids as We(l.
1.3 Exemplary Balarici~ig Pods Embocliiiietit 25 Referring Ãiow to FIGS. l B. an exemplary embcxdim4'Ã-Ãt of a balancing pod is 4howÃl.
('lre balaticirÃ~;pod is constructed similar to the pod pump described abc~~~e. witil respect to FICi. IA. fl.owever, a batanciÃig pod izic1rides two fltiid balancing chambors, ratbe:r thrin. an actuation chamber aD41a puÃ~npirig charnber, and doc;s.not ins;lude an actuation port.
AtldiiioÃia1ly, each balwicing chamber includes an inlet 102 and aii outlet 104. In the }0 excr.Ãiplary embodiment, a irroove.Ã26 Ãs i.Ãic:ludeci on each of'ttÃe balarÃcino clÃair:Ãber ,~va114 120, 122, The groove 126 is described in fiÃi`[Iter detail below.
The nic:mbraaic 11.2 provides a seal between the two chambers. The baI~~iciÃ-Ãg cl~iaÃ-xiber~ kvcÃrk to bailarice tl-ie flow of fluid.Ãntt:à aÃirl out: of the chambers such that botli c.la.arÃibers rÃiaintain atà equal vo:lun-w nate:{-1ow. Althoug1i tl3~.a in.lQts:I02,and outlets 104 for I?

each c(rar-nber are sfrowii to be on the sar.1.:fe sÃde. in other embodiments, the inlet.s 102 ,antf.
mrilets 104 f-or eac.b cftarziber are on different sides. Also, Ã:tie ÃnleÃs'102 azid outlets 104 caTi be on citber side, depending <3n. the flow path in which thÃ.Y bal~ixing charnbGr is i:ni-~.agqatecf.
ID or.re enrbo4-fimen- of the balancing chambers the rriembrane.112 inclutf.e4 ar.r einbc.~dit'ni:.nt similar to the ~~ie described below with respect to FIG. 6A-6G. However, in altemate eynbodirrÃen.Ãs, the rnernbrane.1.12 ean, be over molded or otherwitie cosrsCracÃed such that a double-ring seal is iiot applicable.
14 Metering P-crraitas ayici Fluid Management SysÃeti-i 'I.'~~~e meÃerin4Y pump r;:azi be aziv puriip that is capable of adding ariy fluid or 1.0 rernoving any flui.tf. The f1uitfs i~i-cIucfc f.3atÃ: are ~ioÃ- limit:etf to pharmac;cut:ic:ais, inorgazric compor.r~ids or elements, organic compor.rnd, or e(emertts. nuÃracer<rÃieals, -nutritional elements or compoitnds or solutions, or any other fWicf capable of beirig ptrmpecf. :[n one embodiment, the Ir:ret.ering P-Lrr.a:rp is a membrane pump. In the exeniplary en.rbodin.rent, tl-rc metering pump is a smaller voluzne pod ptimp. In the e~emplax-ti,=
ciiabodiii1eriÃ, the Ãnetering 1.5 pump inc:(ucfes ar-i in(et wrcf ar:r o Ã:[et, simi(ar to a faq,,er pod primp (as shown i.ra:ES1Ã=1. fA #:o- r~
exarii}ile). However, the itileà arid outlet are vrrneraf~y mtrch smal(er tbali a pod fump, and, in one ~.'xenvlar--v er3iho(f:inrtea:rÃ, iriolucfe4 avoicarrta valve-like raase(i rins around either the irifet or otrÃ1eÃ. M eter-ir-ag ptiriips izref~ide a niembraane, and various embo~.-finien ts of a moteria-ig pa,knip mer3ibrane are shown in FYGS. 5 E_5 H. The met.ering f?Lrmpt in son-te 20 embodiments, pr.rnips a volume of fluid out of Ãhefluid IÃzie. Once Ãfie t'uitf is in tiie pod pump, a reference chamber, located otrtside t.lie cassette, usiÃig the FMSe determines the volume that has beeir r~~-iioved.
Thus, d~peiitfirig oii the i~~~~~odimetit, this vc.~fty.me of fIrrid Ãhat has f.~eeli removed will. trot the:n. flow to the f`Itiirf t?trtleÃr the balance chambers or to a pod ptr.nip. 'I'~.,us7 ir-r.sorr-w "5 enibotlimr ni:s, the meÃeritig f3Lrmfs is used to reiriove aN=o1u.n)e ot'tlu.iti t:rc~t.r-~ a 11~:~icf. line. :1~~.

other ornbotfinZer:ttsr ÃfZ~.~ riieterirrg ptinip is Lrse(f torerrrovu a.
vo(trnte of .f1tt:iÃi to prodttci other i esLi1Ãs.

FMS rnay be uscef Ão f~erftirti-i certain fluid nlana<>t:rnGnà 5yst:4art rtxGxrsttremints, Sucfz as5 .for exarrÃp1e-measu.r-ins:s -he volir.rue of su~jec;t flaici putr~pesf Ã.firoi_agh the fa~imp 30 chamber d.tuirig a sÃrokr;: of the membrane or detecting air in Ã1le pumpiiig chamber, e..g., using techniques cfescrik3ed.ir.r U. PatenÃ: Nos. 4,808,1 6.t ; 4a822ti,482q 4;976. f 62, :<,088,51;?;
atrd 5,350,357, which are he.reby incuq)orated bereiÃ~; by reference iÃi their exitiretzes.
M.c.Ãering ptimps ar~. also us~.~d in various emboÃi:iment:s to prrartp a.
sGioard tl-Lritf ittto tl-ie fluid fine. In some embolimetits, the meÃeri.n4ptimp is t-sed to ptir-iip a Ãirer~ipeu[ic or a I:.~

conipottnd irtto a tlEri(i liiie. One embodiment r,tses the metering PLrMP to latr~~~ a VOlirlt-r~.~ Of compound ir-ito aauxzng cliariiber in order to cnristituie a SOILrtion. Itl SOMe Ot i1leSe embodiments, the inetcnrig pumps are ct~~ifigurc.Ydl-~)r FMS vo(trane me,.rsari-Ganent. tti other emb dimentsa tl.renretering ptÃriips fire not.
For FMS metr~~irement, a small fixed reference air chamber is located otat.sÃde oY-the cassetts:, for exanipIt:, in the pnetarnaÃic manifold (iiot shown). A
wrlve isolates the referenc:e chamber and a second pressure seiisor. The stroke voltrme of the meter'Ãti<_F -pttm-p rii;.rv be pr~,'ciseN, c;or.nputeil by c:lt;:}rging the refereiice,~
i:.ha.rrabe,~r witl-i aii-, sneas~uririg the pressuire., atrd tlier-~ opening t:lze valve to t:(ie pum~~ng, eli:~mber.
"I<`he volume of air ori the 1.0 c1iar-sZber si~~~ iiZay be cornpttt-etl based oii ttrc iix~.a(i -volt.rmÃ.Y of th~.Y referenco cliani.l~erarrtl t.tic eharige in pressure wI-aen the referettce cltaÃnber- was t;:o.Ãt.Ãiec:ted to the pump cltamber.
1.5 Valves The c.xeniplaÃ~y en-ibodimi`nt of the uasset:t~.a incluÃies or.ic or inor4 valves. V<tlv~.Ys ;tr~.a l5 used to r~~mlat~ flow bycapei~~~~g and closing flr:-id. lines. 'I'h:e -valves irj cltided ifli the vaci0us embodiments ol'the cassette iii.olLacie one or more oi't:l-it: 42611~~A.ving:
volcano valves or s~iiootli va:lves. Ill some embodiment o1't(i.e cassette, check valves maybe iris: Iiided.
Er-nbc.~dimi:.nts of the volcano valve are showr1 in FIGS. 2A aFitl ''.B, wliile an embodiment of tl-ae sr-tzooÃb. valve is show-r.r in. FI:Cg, 2C. Additio:nall.y, FIGS. 3>'t-413 show cross sections of - 0 an exemplary eiiilrodiiiient of the pod pump in a cassette witli aii iÃilet azlcl outlet valve.
Generally speaking, reciprocat-iria, posit.ive-cii5placemezrt pa.araps oI=th:e typesjust described maN include, or Ã~~av be r.rsed in coqiunctÃon wÃtli, varimrs valves to control fluicl flow through the pErnip. ThÃat, for exararple, the r-ccipr~ocatirig posit.ivo-tl.ispla.t:ement pt,in~~
or the balancing pods ittay iarclr.ide, or be used in s .w~juns .tian w.itlt, an irilet valve anfl./nr art 25 outlet valve. The valves may be passive or active. In the exemplary ~,'n-ibc?dimer-it of t.l-ae:
reciprocaÃÃttÃ~ positive-displacr=wrtieitt puÃitp the metnbraÃteis tirred backancl forth by positive a~~d negative pressurizations, or by positiv-e arid vent tk) atmosphere pri,ssr.rrzzatzfans, of a gas provided through the pirew.n;at.ic port, whicl:r co.ariec.ts the actuation chaniber to a pressure actuation systeill. The restIlt111g reL'=1p1'oi:i:lt[i3g act1oI3 of the membrane pr.t~~s flttld, rtito ti1c }0 purnping cl.rtrrrilaer .from t1-ic inlet (tl-ie outlet vEt1ve prevents liquid fiom beiaig sticked. back ittt:o the ptrmlaittg chamber f-raiti the outlet) artd then pushes iltefluid, otflà of the pump.itrg c(uirtzber through the outlet (the inlet valve. prevents fluid i:roii-r beiix;F forced back from tl-ac inlet:).

In the exemlalarv. embodiments, active valves control the fluid flow through the.
pump(s) aÃ.id the c,asseÃ:ie. 'I'l~c active valves may ~~ ~iettÃatecl by a controller i.Ãi sucha Ãnantler as to direct flow iÃi. a desired directiom S~icii. t~~l arranguaÃter.tt: wcj-Ltl.d generally per.Ãnit tl.ÃC CODtroller to cattse flow in either direction through the pod ptÃ.Ãnp. .l.n a typical system, the flow wotÃltl normally be in a first dÃrectioti, e-g-, from the iÃiIet to the otat.let. At Urt.1i11 other tÃnÃes. the flow may- be directed .iti the upposwe direc:tion, e.g., .fro.--il the outlet to the iailet. Such reversal of flow may bo employed, for example, duriflig pgÃmiÃ-ig of the puÃrip, to c1ieck for ziri aberrant lirte condition (e.g., a liÃ-ie oc-c:lGtsiorit blockage, disconnect, or leak), or to cl~zv cnabert-ant line condition (e.g., to try to dislodge a bls.~c~~age).
1.0 PtieLtmat.ic acttÃati<3ii. o:f'valves prc~-k-ides pressure t;oÃitrol and a. natural limit to t.h~.Y
i.iiaximÃ.i~~~ pressÃ.Ãreth,it tY~ayl~~ ~evel()I)edinasvstem. ftithe con iext of a svstem, pnetÃinatic actuation has the added benefit of providing the opportunity t~.~
Incate all the solenoid cnÃ.Ãtroi valves oti or-ie side of the 5~~~,t.e~~:~ ~~wa~+ f:rc~~~-i the tltiic~l l~~atl-Ãs..
Referring now to FIGS. '2'A atid 21B, sect:i~.~nal vi~Nv-s oi'M.,-o embodiments of a 1.5 volcano vziIve aretil.Ãc>ti4n. `l'l~e vnlcaiicà valves zire pi.le-LÃmatic:alty controlled valves tl.Ãzlt nuty be used in eÃ-zibodiÃiieiit.s of the cassette. A ~~~enib~~~~~ 202, alofl~,,;
witli the mi.dplaÃe 204, defines a valving chan:iki~.~r 206, Pneumatic pressure is provided throttgh al*nettn-iat.it: pcÃll 208 to either force, witli positive gas pressure, tlie, membrane 202 against a va1ve seat 210 to close the valve, or to c~~aw, with Ã~~gative gas pressLÃr~,~, or in scaÃi-it;
eÃi-iboclimeÃits, with r>e.iit.
20 toai~~io>p1~erÃc liressÃ:Ã.Ã-e, the meniba ~:Ãle away.froni the valve seat 210 to cÃ-pen the va1ve. A
contro1. gas chamber 212 is defined by the membraÃie 202, the top plate 214, and the matll>lat.e 204 Tlze midplate 204 has aii iÃ:Ãc1entat:ion f:orr.ÃieÃ1 on it, into which the tr~em.1~rane 202 is placed s~.~ as to t'~.~rm the cotitrol gas chamber 212 oti oFie side of t13o moi31t}rane 202 aÃad the vaCo.icig clÃaÃ:-nber 206 oti the other sside.
"."? The ~~~eurriatic port 208 ~s def-Ãaeil by a cllarinel :t=c~rmed i.r1 t:l-ie top plate 21.4. Bv providing pt3C'.uIl:1at1C:: control. of `Jev4#`al v~~lv~.':i i23. i:l caJ4ette, '%'all.\~Ã.~`s can be gaTIgC':(i together so that all t:1ie valves gatiged to<.~etl~~r can be ope.ned or c(osedat Ã:1-ie sarne tinÃe by a :i11gle 3otÃ:Ã-c~.~ of pnoua~~itic pr~.`ssÃzre. Channels fon-ned. oti t.hÃ.Y
r.y.iid~.~laÃ-~ 204, corresponding with "luicl paths along with the bottom plate 216, define the valve.inlet.'?18 and the valve outlet 30 220. Holes forrt~~ed tlirough the miclpl~.~to 204 provide communication between the inlet 218 atid the vaIviÃag chamber 206 aiid between the valvii3- chamber 206 and the oLÃtlct: 220.
100011 The membrane 202 is provided with a thickeÃied rim 222, which fits tiglit1y in a ~.~roove 224 in the iniclp.lato 204. ThtÃs, the Ãnerribrane 202 car.~ be plr:tcod in a:Ãltl held by the groove 224 k3ef_og-e the top plate 214 is coii.Ãiecied to the ~i-iidplate 204.
'I'btas, this valve design Ãnay i~~~part benefits in Ãnanufacatre. As shoNvn in FIGS. ?B aÃ-tct'C, tl-tc top plate 214 iiiav inclÃ.tt.-le additional material extcaiditig into control gas chamber 2'1 2 s~.~ as to prevent the merfiZbrane 202 frc?Ãn beitig tÃÃ:-gctl too n.ttÃctl inr.t direction away froi n t.ht.Y gt-oovc 224, so as to prevent the membrane's thickened ri.ni 222 from popping atÃt of'the groove 224. The location t.~f t-1ic l.~neÃamatic pc.~t t 208 ~.N~ itll respect to the cotitrol gas chamber 212 Varic.4 in the two eÃnbodiÃ~nc.nt4 4liowti in.FICIS. 2A arid'_M
FIG. 2C shows an c.inbc.~ciiine:.nt in which the valving chanibc:g lacks a valve seat feature. Rather, in FIG. 2C, the va.tVe. iD this ~inboditneitt does tiot ii3cltx1c any vt31c;aiio #eataar-es a.Ã-tt.-l tlitEs, ti-te valviÃ-tg t:,ba.mbcr 206, i.e., the t'1.Ã:ticl side, does Ãiot incluc.leany raised 1.0 feat.trres ,tÃtd thus is smooth. This czxtboclime::nt is used in cassettes used to pump fluid setisitive to shcarino. FIG. 2D shows an embodiment in which thevalvi.a4 charnbcrhas a raised area to aid iÃt the sealing oi'Ãl~e valving mcmbrane. Referring Ãiow t~.~ FIGS, ZE_'~, varic>us embodiments of the valve r-iiemb.Ã-at.~e arc shown. A(-tltotÃgb some ex.eml7lzirv embc?di.mcnts have been shown a:tid described, in other embodiments, vaÃ-ia:tiorts of the valve 1.5 aÃ-td va(v.it.ÃM nie.Ãnbranc ~-ii<iy be tased.
1.6 Exemplary Embodiments of'tlie Pod Membmne In st.imc eml.citlimetits> tlic- mcÃii~.~aratit:, has a variable cross-sectional tliickness, as slzowtt inf'I:Ci. 4, 20 accommodate tlio streÃigth, flexttral and other propcilies of the choseÃi membranes materxals.
':E'l7.it.Ãtaer.r thicker or var-iablc i-iiembraz~e wall thickness mziv also be tisecl to t-nzmagc the membrane thereby eÃicottragiti,.y it to flex more easily in somc areas tlian in ~.~therarcas, thcrcbv ,ti.t.lin;.~= in the rttat-ia.gctiZCtit o#'ptÃi-tipi~ig actioti and flow of'sa.tbjoct f7tÃ.id in th~.a pump cliamber. In fliis embodimctit the membrane is shown having its thickest cross-s'ectional 25 area closest to its t:ctitir. However in cgt(xur enibot.timciits btÃviÃig a. mer-tabrRtt-ic with a varying cross-sectioÃ-ta1, the tbÃckcst and thinnest areas may be i.a any location oÃi the membrane. Tht.t4, for exaniple, the thinner cross-section may be located near the centcr an~.1 the thicker cross-sections located closer to the perimeter of the rnc.mbt`aaac.. Still other configurations ar~, possible. ReferrÃti<_x to FTGS. 5A-5D, one ci3-Ãbodit31eiit of a membrane is :30 shown lzav.ir.Ãg various stt.Ã-fzic:e embodiments, these i.n.cltÃde smooth Ã.FI(;i. SA), rings (FIG.
5D}, ribs (:l=l:G, 5Q, dimples or dots (l;IG. 5B;) of variable t[iic:.kzic:~s and or geometry located at variotts locations cxi-i tht,~ acrtÃ4Ãtion and or pumping side of the mcmbt=a~io. In o1-ic enibodinient of the tt-Ãen3bra.ne; the membraric liaas a tangential sl(ype in at least ozic section, bt:tt in other ornbotlirn~.`nts_ the rnembr<3n4` is cotr.Ã~.~letcly 5t3:loottt tjr ;~~ibstazÃtia.i.ly ;'t3.toc?th.

Referring now to F1GS. 4C, 4E ancf. 4F, air alternate 4'Ã~~boCIimeÃ-it of the mtarnbrane: is showti, Iii this embodiment, the iÃieriibraiie has a dimpled or dotted surfac.e.

The nÃeraibrttne may be macle of ariy flexible inat:erir.tl.l3av.ittg a desired tlttnability, and coinp:ÃtitailÃty- witlz 11-ic subject fltt.id. T1-ic mernbrtine can be rÃ~ade fioan any anate.nal that.
mav flex in response to tlttid, liqEÃid or gas pÃe5sLÃ:re or vacLÃtyin applied tt.~ thi actt.tation rliaÃizber. The nÃen-ibrttne .ÃntÃte ria l nittv also be chosen for 1MV.iCÃ.Ã1.ar bio-compatÃbility, temperature compatibility or compatibility wÃtli various sLÃ~ject fltait.is that Ãirav be ~.~t.tÃ~~pec~
by the ÃiieÃtibrzirie or introduced to the chambers to f.acilit.ate mov4ment o#'#.1ie i~ierizbrarie.
[Ãi the exeirzplar~ embodiiiieÃit, the ÃriernbÃane isniade t:roiii bà ;b elora~ation silic:.oÃie.
1.0 f:lc7wee>er, in other ert-Ãbot~iments, the ni nibran~.a is made f:i'ort7.
any ~,Yl.ÃsÃc)in~.ar or rttL~ber, inclriclitt;=, bÃ.Ãt ~iot limited to, sÃlicoÃ-te, Ã.Ãrethane, nÃtrile, :f*==,l'D;v4 or anv other rubber, elastomer or flexible niaterial.
The shape of the membrarÃe is ciepericlerit oti ti-iÃ.ÃItiple variables. '-i'h:ese variables itictucle, but are not [irait.ed Ão: the slrape of;-the cham1~er, tlio. size ol'`tlie char~iber; the sul~jeet 1.5 fluid c:l:Ãaract.ecistics; the voftaÃ-zie ofstgbject kJuirl pÃimlaed per stroke; and the rÃ-zeazÃs o.r nÃode of atiachment of tlie membrane to tPie hoiising. '1'he size of the membraÃ-ie is dependent oii.
M0ltiP1~.~ variables. These variables iticltikle, btit are not limited to: the shape of the cltaÃiiber; the size of the cI-aambea; the subject fliÃ-id c:,haractex-.Ãst.Ãcs; tl~e voltflme of subject 11tÃid ptimpee~ per stroke; and the nicans or mode of att.a.i:f:Ãment of the membrar-ic to t1le 20 housizt.g. 'Tltus, depetÃdit7g oti these or otI-te.a- variables, tlie.
slta:pe and size oftkÃe ÃitembraÃie MaY varv in various embodiments.
The meÃ.Ã:Ãbra~~e car-i 1-~ave ar-i_, ~r thÃcfcr.iess. (-lnwee~er. isome eÃ-~~l~c~diÃ-~~ezÃt~5. te rrange ~, (if thickness is betNveen .002 iriclres to.lL5 inihes. Depetidi~ig oii the materi~aI ri.sed for the rnernbÃ-azre, the desired thickness may vÃiry. In one embodiment, high elongation si.licor:Ãe i4 "."? used in athic,kness ra.Ãwi.Ãw firrsrn.01 5 izicl7es t:o.050 inclies. f-lowever in oÃlier embodiments, the t-hickriess mav vary.
In ti-ie e:ti~rnplary embodiment, the membrane is pre-#'c~rÃ-iied to itiE..liide a sLrbstantially dc~rne-shapo iia a[ .Ieas[ part t}$'tlÃe area of the rnembrXÃtte. f_}rÃ~.a Gmbodiment of the tlo.Ãne-shapei-i rneÃnbrane is sl.aown in FIG. 4E and 4F. Again, the d.irÃiensions of the 30 dome. may vary based oÃi some or more of the variables described al.-~ove.
However, in other eni1;~odii-arecÃt:s, the iiiemb.Ãaiie r~iay not i~ielude a pre-fc?rar.Ãcd clcrixBe s(-Ãape.
In the ~~~~iiplary embodinieriÃ, the membrane dotiae. is t~~~~~~~ed tisiÃig liquid it1jection rÃroltling. :1-1oweverr Mo[her ~.`t bocliment:s, t:1-ic doÃn~.a may be forr-ned. by using cot~.ipression molding. In 4Ãlt~,'mate inibor1inients, the menibraÃ-ic is substantially flat.
In ot1-ier erzibodinients, fhe dome size, widtb or hei wYlit may vax-v.

In various ernbodimontt, the nicrnbra~~e may be hÃ.Yld in pIXic~.Y by various mcazis and.
IIretIrcXls. Irz orre cnrbodinrerrt, the menibrane is clamped betweeai the port.ions of the c,asseÃti:., and in st.~me of these c..nibodimerrts, the rim of the cassette may incIriEi:o features to lip-at' the nienrbrarre. ln others ot'thi;s enil~odimt:nt; tlic merrilarane.is claarrped to tt.re cassette using at least ~~ic bolt or another device. In another embodiment, the mc.Ãribraiie is over-riio1cled witli a~~ece of plastic and therl tlie plastic is weIde.tl or r3rtterwise attached to the cassette. lrr ai.rc?tlrer embocliment, the menibr-ane is pinr;hed betejreen tlhe niid plate de: c-ribed 1.0 witb i-esIaect to FI.GS. 1A, and (B an.tl:==, the bottom plate. Although some Gn.tbodin.terit.s for attachment of the tiiemb.tarte to the cassette are, described, a.Ãly metl-aod or means for attaching tlie mennbrane to the cassette can be used. 'I'~~c meriibrane, in one alteriiate embodiment, is at-taclred directly to one portioii. o.{*t:l-re c:w;sette. In scst-~~~ embodiments, the mernbrane is thicker at the ed;we, where t}re naeriibrane is pinChed by the plates, than in other 1.5 areas c3t'tl-ie membrane. :t.ii sor-zle embodiments, tli.is thicker area is a gasket, .ir.I yome embodiments an OHring, riia4 or any oÃber s~iaped gafikeÃ. Referring again to 6:1.-61=3, otie ~.~niboeiiment of the menibr<zaie is s~~vm with two gaskets 62, 64. In sc~~~le of these ernbodirnents, the gmsl<:eÃi s3 62t 64 provides the atta.eh-ment po.Ã-nt oI'the nierrtbrane to z(~e casseÃte, 111 other embodrm~,'nts, the membrane irictudt's n-iore than two gRkski'is, 20 Memtiraiies with one gasket are also iÃtelLided in some embodintents (see FIGS. :I~'1Ã.tS. 4C'-4F) Ir~ some embodiments nI'tile gasket, tI~e gasket is configur?r~s with. the mernbrane.
However, in other embodiments, the:. gasket is a separate part of the mombrane. IlI some eniboclinlents, the gasket is ma.dei=ronn kl-re sainei-rraterial as the rneinbrane. 1=Ic?~~~ever, in.
other embod.irnents, the Lasket is made of a ma.t:er-ial dit:t:er~iit from th:e rnennb~~t~:lie. In some embodiments, the gasket is 1:ortrred by over-molding a ri.r-ig arota.riÃl the rnGmbranG_ 'T'he oa.sket ca.Ã-r be a..i-iv shape rir-ig or seal desared so as to cc~i-iiplement the pod pump 1-ioiisi.ti~;
t.r-iibodinierZt. In. sona~.~ embodim.c.`arts, the ( ga.sl:et. is a compression type gaskGt.
1.7 Mixing Pods 30 Son~c enibociinients oI'the cassette inc:ltrde a mixir1gy poci. A mixilrg pod includes a eliaÃ-ztber for mixirtg. :(rt soÃ-rie embodiment:sõ ttte mixing pod is aflexib(e strrietitre, a..ndirr some embodiments, at least a section of the mixing pod Ãs a flexible staLict:tire. The mÃxing pod can irxeI-Lide a seal., such as ari r~-r.inw_ c>T a.1-zrezi~_~brane.
'_i'be nxix.iar- pod carz be any shape desired. In the exemplary emboclirnenÃ, the mixing pod is similar to a pod pr.imp except it I I~

does not incitÃde a Ã-neml3ran~,~ an.~.1 does not include an actuation port.
Some i.'n-ibc?dimei-at.s of tl-iis ~inborliment of the inixina pod include ati o-ring seai to seal the i;aix.ing pod chaniher.
Thus, in the exc~rnp.lary, oinbotlirnent, the zZ:Ãi.ximt> pod is a spherical hollow pod wi.tl~ -a flaid itilet and a tl.ui.cl outlet. As w.iih the po(l p-tÃTiips, the cliamber size ca.Ãl, be any size desireci.

2. Pressure Pttm~.~ Acttiati~.~n Syst_om FIG. 7 is a scliem;at.ic showili4p one eÃnbocli.ment of a PrCssi_are at;tUatioll Wstefrl that may be tised t~.~ actuate a pod pr7n1p with 13ot1i positive and negative pressure, srich as the poti punip sliti-wii, in FIG. 1A. The pressure a:ut-uationsysteni is c:a.pabli.~ of iitierÃiaitteiit.ly or alternately providing positive azid iiegative presstÃ.rizxitions to tlie ~.~as .in the actuation 1.0 clia_Ã-sZbor of the pocl pÃimp. 1-iowever, in sort~o ern.13L}di.rnonts,1":1G. 7 does rÃfat:;:Ãpp.ty for izI
these entbod.iÃ.nents, actuation of the pod putnp .Ãs accomplislted by applying positive pressure a:Ãitl ~~ont to atmosphere (again, not shown in H~.3. 7), '1-`l~~ pod pump ~ inchÃ:dirrgtlae flexible memt}ray-ie, the inlet, the outlet, the pr.ieLrty-iatic port., the punil:)iriM e(-zambez-, tlle acwation chamber, atrcl possibly iirclEÃdi~ig aÃa itilet check valve aiid aÃi ntitlet check valve or 1.5 nth-ier valves ------ is part ot'a larger disposable sySt:ern. ':['he la~~ew.na.t.ic actt,tat_ic3zà yystem ------includirrL, an actuation-chamber pressiire traÃ~sduc_,er, a posit.iq=e-s~~P~~1y va[v~:, a t~e;>ativer supply va:lv~.~, a positive-pressure gas reservoir, anegative-presst:Ãre giÃs reservoir, a positive-pressure-reservoir pressLÃre transducer, a ilegative-presstire-reseri=oia-pressiÃt'e transducer, as well tÃs an electronic controller including, in some i'Ã-i-ib~.3dimeÃ-its, a user rnterftÃce c:onsol~.' 20 (sticlY as a toaclt~pauel sc.Ã-eeÃa) ------- Ãiia.y be part of a base unit.
The positive-pressure reservoir provides t~.~ the actuation ehatia:ber tlle positive press .tizat.ion. of a control ~<ic to ~ir~e the membrane towards a l~~~siti~?z~ where the ~~ci~~~l~.ir:1-c:ha:rnbi:.r is at its minimu:~n voltrn1c (i.e., the -position where the n-ieml.~la.ne is against the rigid ptii-izp in s.=,-ch am~~er wal.l). 'I'he.negative-pre1sure reservoir provides to the acti.Ãatioal "."? chamber tl-ic tiegative pressurara.tioii of Ã:1ie t.f?.at:rol gas to urge the i11embra.ne in t:}~e opposite dir~.~ctioii, towards a l.aositiosa w1~~re. the pumping c1-ianil~er is at its inr:rxirnt.Ãrn. volu:Ãr.te (i.e.z the pos.itYori where the membrane is agai.Ãist the rigid act:uationrchaÃ-iiber wall).

A valving mcctiani`m. is tts~.~cl to cotm,ol fltnti t;ornmunicat.ion b4tA-vG~.an each of tllise reservoirs ariti the actuation cluunber. As sliowii m.li I.G, 7, a. separttte valve .is tised for each 30 of the r~.~servoirs; a ~.~ositivessÃapply valve cc~iitrols fILiid c,f.rÃm-ntÃ.raicatioti laetwoen th~.~
positive-pressure à esenoir a:aid the actuation c:hainber, azÃd a ~~ega-tive-suppl~, valve controls fluid communication betweezi the negative-pressure teseÃ-v~oi.r a:nd tlie aeÃtiat:ioxi c::l~amber.
These two valves are conÃrollod. by t:l~e. cozÃt:roll~.ar. Attt:n-ia.tively.
,.Ã single thr~o-w,:1y valv~.a may be ~~sed in iÃcci of the two separate v4Ã1 ves. The valves may bi bitxary, on-off va1ves or vari able- res tricti c~~i va 1ves.

The conÃr<aller also recoives pres;tÃre irlt=orÃ-nxÃt.ion froin. i1ie tttr~e pressure transducers: aÃÃ ttctuatiolÃ--cl.ÃtÃrÃ~ber pressure firziÃiscl-LÃcer, a posit.ive-pre-s,-LÃr,e-reservo.Ãr t.~ressLtr~, transducer, and a~~~ pr-esstare iranscltzccr. As their names Sir;=i~'C'St, these transducers re41~ectively Ã.~~leasÃ.rre the pressure i.n the at:tuat.ion. t;hanibsd.r, the positive-pressure reservoir, aÃid the:. negative-pressure reservoir. The ai;tt.tationacl3aniber-pres<sur~,~ traaisciÃÃc<er is located in. a base Ã3 iiit but is iD flrtitl coiraiitÃÃiiic:ati~~i witli the Ãzctcration e,haniber tlirou4:lz the pod 13Ã:ÃÃrzp pÃietiÃ-iiatic port. "t`he coiitroller monitors the lare5sÃ:arein the 1.0 tk'vo rt.servoirs to olZsLtre tl~ev aro 1?roperly prÃ.YSsti-rireÃ.( (Ã.Yittter po5it.ir Gly or ~~ogatively). In w~~ exenilalary eiribodiiYietit, the positive-pressure reservoir may be maintainet:t at around 750~~~~iiHG; while the negative =l)ressEÃ e reseÃv=~.~ir may be maintained at around -450ÃilmHG.
Seiil. refer~-ir-ig to FI.Ã;F_ ". <i cornpres5or-type 1?iÃmp or- pt,Ãraps (not s1-iowra) .Ã-ziav be used to maintain the desired pressures In tliese reservoiis. For example, two iaidepezlclezlt 1.5 cijriipresscsrs may be used to respective[yserv-ice the reservoirs.
Pressure in the reservoirs tiiav be ma~~~~ed using a simp1e laarig-bas:Ãg L,t?iitrol tecl-izi.ique, ifli wlric:.li the c~on~pressor servicing ilic positive-pressure reservoir is ttrmed oti if the pre;Ãstire in the reservoir falls below a predeterÃniÃied t.lireshold and the cotnpre%soÃ- se.Ã-vic:irig the negative-pa-essure r~~ser-soir is trÃriied. on if the pÃ-esstÃr~,~ iÃi the r~,~servoir is above ia pr~edet~.'rmir-ied threshold.
20 "1"t~~ amouut of hysteresis Ãirav be the sarne for both reservoirs or may be different. I':igliter contro1 of the pressure in the reseÃvoirs can be achieved by reducing the size, o1;-the 1~~~ ,-;teresis band, aitlioci-;1-i th.i5 will generally result in lrigi-ier eyelitia trer{ue.acies of the c:c.`~Ã-npressors. If very tiglit control of the reservoir pr-esstares is required or otherr.vise desirable for a particular appIicati~3.Ã~., the ~~ar~~;~-l~~ÃrÃg technique coti1d be replaced witli a PID
"."? control tec:lltlis~~~~ and could use PW.M sigrials; on the compressors.

The presstÃro provided by the positive-prc.Yssti-ru reseno.ir is pr4#urXÃbIy strong enough ------ u.nde.r normal c:c~~idiiiÃ.~ns -----tcs ur(,e the metribrane al( the way agai.Ãlst t:he rigid ptimpirigH
c1iaÃ-iiber wall. Sirnilar1.Z~, the ra~gativ~.~ l.-~resstirc.Y (iØ, the VsÃcuum) provided by the negative-pressure reservoir is preferably stro.Ãlg cuough ----- under Ã-:Ãcsrtrial conditions - tc) ~irge the 30 membrane all the way against the a.ctu<ttioÃ3Echamber rall. In a furth~.~r preferred eml_oc3.iMerÃt, however, these positive and ne4~;at:.ive pressuÃes provided by the F-eser~~oir4 are within safe eÃ~ough iiniits that everi with either the pÃasitivenstapply valve or the Ãiegatzve-3Ãrpply v,tl.ve opotZ all the wayr Ãh~.~ positive or rÃegative prÃ.YsstÃ:Ã:e <`rppl.iuc~ agains;t the membrasre is not so stron~= as to ~.1arnage the pod ptÃÃiip or create a.tnsafi.~ tltti(i. pr~.'ssltres (e.g,, tI-iat iiiav lixi-rm a patieÃ,i reo.eiviÃa) purirped blood o-r other fluid).

l.t will bo appreciated that other t.y-pe: may be i.ts~.a(3t:o anov~.a the nien-ibrane back and.fiorÃb irlstCad Of the Ã-wo-i-eSCrN'0ir pneum:atic actttatic.3n systetr.i:al.rown.ui FIG. 7, although a tAvoyreserv~.~ir ptiiEÃ:t natic~ acttiatic.~ir system is generally prefert e:d. For exaÃizple, alternative PrI~::tt.111,ÃtiC: aCiteation syst~nis.may include cither a si~igle posit.ive-pre~sure resert-voir or a siYigle negaÃivi6pre.ssure reser-voir along witli a single at.tpl3ly valve and a single taiik presstÃre st.risor, ~.~art.iculaily in cc3iiibiiiatioii.
wiÃ1i a ri.'silzs~iit ri3r:.n-ibrane=
Stich pneunratic aetuaÃ:ion systems Ãnay intermittently provide either a pos.iti ve gas pressiare 1.0 or a Ã:iegtkt.iv~~ ~,~as presstÃ.rc to the aci-tÃat.ioii. c:l'Ã<~rnbc.Yr of thÃ.Y ptxdpuanp. Irt c.~mbodim~.altts Itavir&g a s.iu{wle positive-pressure reservoir, the pu.Ãnp may be operated by interinitÃently providing positi~~e gas ~~ressEÃ:re to the actuation cl~az~~l;~er, eatasÃii.;
the i~~ertil~raÃ~.e to move toward the pumping chamber wal( rxr~~ expel the co.txtezÃt:s oi'the pun~~~inM
ehamber, and releasing the gas pressitre, causing. ttio membrane to return to its relixed posit:Ãcazi aÃi~.-1 draw 1.5 fluid.inin the ptanping chainber, l:n embodiments hrivin4 a s-ir-igie zÃeMtÃtive-1~~es5tire reservoir, t.l~e pump mav ~e operated bv inter.ti.iittent.ly providing -negati~~e gas pressitre to the actuation chamber, catÃsin~~ the m~.'tzil:lrÃÃ~i~~ to rii~xv~~ toward the a~:itÃ~~tat~a~ c1~~t~~~l~~~r ~? <~:11 aitd draw fILÃid iitt.o the pampittg chatiiber, ~~id releasirilx the gas pa-e:ssu:re, causing zlie n~embrasre to r~,~tttm to its relaxed position and expel fliÃid from the ptÃs-iiping c:ha1-iibe.r.
20 3. I~ luid:Handl ing, As s~ownand described witb respect to ~~IGS. -'?A6~?D, a fluid valve in the eaernplaiy t.rnbodirrient à .c~i-isists of a small chamber witli. a flexibl.Ã.Y
r.rit:mbrane or rt~ombranG across the center dividing the cltaÃnber into a fluid[iaif and, a pneumatic ~~~lf. 'l'he t'irflid valve, in ttie 25 ~.'xemphuv erubodiruentõ has t1i:ro~,~ eri.try't'tiit ports, twca on the fluid hktl.f of the chamber ,aiid otie the pnerÃznatic halt'of the cltatt-ilaer. The port oit the ~~~~eumatic:
half of t'1ie cttartibe.r eatz supply either positive pressrÃre or vacÃ.Ã~~in (or rather than vacuum, in soÃiic embocliÃx~onts, there is a vent to atmosphere) to the cl~~~~iber_ When a vactitxm is applied tc? the pnetÃn.~atic portion of thc, c~~m-nber, ttic Ãiiciiibrane is pttlletl towards the pneurnatic sit.le of the chamber, }0 CiCa.riaz_; the.flu.iti paÃb and allowia3g tlui.d to fiow Ãnt.oRÃnci out i`the .[~luid side of the cltaÃliber. When. positive pressure is applie~.-~ to the prt~~rnatic pcriiora ot'the chamber, the n~embrasre is pushed towards the fluid side ot'the chamber, blocking th~.~
tluid ptttl-i aÃld preventing fltiicl flow. In the volcaiio valve embodiment (as showii i.Ãx FIGS. 2A-2B) oÃi one of the fltiicl pfart,,,, t-h;tt pcai-t seals off first when closing the vÃ:-1ve Ã.-nd t.ho rernainder of' Mtid in the valve is expelled through the ~.-~c~ft withoÃit the volcano f4attÃre.. Additionally, in onc enitodiÃ~~eni of the va.lves, showÃa in FIG. '21), the raisecl :lcature bciivccii the ports allows ibr the rnc.mbranc. to seal the two ports froÃn each ot.laer carliur in the actuation stroke {ix., belore. the i.neÃnbrane seals the ports directly).
Referring again tc.`i R14.:r. 7, presstare- valves are used to operate the pumps located at dil"feteÃià points in the flow patli. `I`hiS architecture supports pressure control by LÃsizig twt) variable-orifice valves aÃicl a presstire setisor at each ptÃn1p chamber which requires pressctre c.otztrol, In oÃic eml3ociimeri.t, one valve is coÃ~~iecte,'ci to a high-pressGÃre som-ce aircl the other valve is coiiiiectetl to a 1ow-pressure sink. A high-speed control loop nionitors the pressrare 1.0 setisor atZd coritrtils the valve laositioÃ:ts to ni,ÃirÃt.a.in t:l-ie necessary pressure in t.h~.~ pu:1t.1p cliamber.
Pressure sensors are used to monitor pressure in the pz~eumatic portioÃi of the c}~~~iilaers tlac:Ã.Ã:Ãselves_ Bya1terr-iatiii-lactwcei-ipo,-,itivc: pre:~sÃir~e-,Ãi-idvac.ÃiÃim. ozà tl-ÃepzictÃÃlÃatic sicleo>t:
tlie chamber, the membrane, is cycled back and fort:li across the total c1iamber vcalaine. With 1.5 eacb cycle., fluid is cl.r<~~~~i-i Ãb.ror.Ãglà the upstream valve of the .ii.ilet fluid port wt-zc.Ãi. tl-ie priciÃmatics pÃÃ.ll a vactit:tm cati Ã1ic pods. `['bc tluid is tlie.Ãi.
subsequcr.rtl.y cxpcllecl througib. the outlet port a-id the downstream valve when the pnetÃmatii:s deliver positive presstire to the pod5.
In niaÃiy ~,'mbodimelits, presstire ~.~t.triips coÃisist of a, pair of chambers. When the two 20 cliambers are aÃrà 180 degrees out of pl-ta~e froÃ~~ one aaiiotlicr the flow is essezitially coritttiLtous.
4. Volume Measurement These -f`Iow rates in the cassette are cfsritrtsllcrl Ã.Ã5ii.1g pressure pod priÃ-zi17s which can 25 detect cÃtdaol`ast:rrake. An otiter control loop determitics the correct pressure valtÃ:cs to dcliVer t(ie rcqtxired flow. Pressure pÃar-zil~s, cazi run an ci.lci ol'st.roke alg,,or.ithira to detect wlzcrz cae:la stroke completes. While the membrane is m~.~virig. tlre measured presstire in tlie chamber tracks a desired sinusoidal pres4t.Ãre. When the membrane contacts a chamber wall, the pressure k~ecoÃ3ies cotista:tit, aio longer Ãrackingthe si:Ã-itÃsoirl. ~ITtxis c:hati~,a;c in. the pressure 30 signal is tÃsed to detect wh.en, the stroke has ended, i.c.> the end-of-stroke.
The pressure punips l-aave a known voltÃt3ie, 'i'kius, aÃ-a ezid of stroke indicates a kÃic~~~~n volLÃme of tliÃid is in the chamber. `['1itÃs, using the end-ot--st:rokc, fluid flow may be controlled lfsIn4' r<ite equating to vt?l-LÃt.1:te.

As tlcsc.ribed above in more tietai1, FMS Ã~iav be its4'd to d~,'ten-ixitie t1ic voitime. of fluid pttÃ-xil~ed bv the metering ptÃmps. In some embotlimetlts, the nieteÃ-ing purills may pt:aTlip fluid witltcÃttà tÃsin~ t1Z~.~ FX'ls vc,lt.ttt-ie tZÃeasur-ert~ent syst:t`t-liT however, in the exemplary et3-Ãb dimentsa tl.Ãe:FMS voItam.t:. rÃ3cfisurertient system i~ used to calculate the exact voltÃmix.
~~f flttid. ptt~~pe(l, 5. Exemplary E.tnboc.li.ÃiÃt.a.r.at of the Pttt.rtlai.Ã-Ãg Cassette:
The temis itilet and otttlet as well as fluid paths arc used for description ptart.~osc:~~
only. In otlter ~,'Ã.nbozliÃ.nent.s, an iiilet can be at-i outlet. The,~
denotations simply refer to separate entt~anceareas itito tl-ze casset:te.
1.0 The tlesig-nations give :f-t)r tl-ie :f-lt,itl itilet.s (wIiicl-i can also be -flt.Ãitl outlets), for example, first flt.tid outlet, secoÃid fluid otttlet, merely indicate tllai a t7t-itl may. travel out of or ixito the cassette via that itilet:'ot.Ãtlet. In some cases, ~iiore than otie inlet/outlet oti i(ie sc(-tert7atic is closi4'nated with wi icier-iticttl ntir.i~_~e. This zy-ierely describes that all t3I`the Ãnlet.`outlets having tliat designation are pumped by tlte same. meteriÃig pump or set of pod 1.5 pumps (w1-tich in aftet-naÃ.e etnborliments_ can be a single pod lat.Ãmp).
Rete.t-ring tiow to FIG. 8i aa~ exemplary embod.Iment of tl-ie t']tjid schematic of tl-ie pu-npitzg cassette 800 is shown_ Other schernatic.;, zire reacfily cliscet-nable. The c;assette. 800 itielt.icles at least oue pod pt:tnip 820, 828 ant.l at least one i3ieteri~ig pttmla 830. `I'he cassette 800 also incltÃcles a fltÃi:ci inlet otie 810, whc.re, fliticl tanteÃ-s the cassette from a sot.trc:e.. The 20 flt.rid iÃiclt.tdes a flow rate lirovided by tbe, at least otie pod pump 820, 828. '1 (ie cassette 800 also includes a fltÃicl otttiet one 824 where the flttid exits tlie cassette 800 Ilavirtg a t~ow rate provicled by octe csl"the <it least csrte pod ptÃii-ip 820, 828.
The exemplary etnbc.~climc..nt iiiclÃ.ides t3~~~ pod ptan1ps 820.. 828, however, in alternate eÃ-nbocliÃ-tients, one or more pod ptaÃ-1ips rÃ_Ã-e included in the cassette.
l:rt the exeÃnphan, eÃ~til~t~~IiÃ~i~:et~t, two l~a~tl. pumps provide 1=c~t= st:ea~.~~ flow.
':~~~'lie irieter~fl1~õ prÃii1p 830 punips a voltÃ:rne of ,c.coÃ-it.l flEticl from a second lltiicl. sotÃ.rct into the fluid lirÃu prior to t.ht;. .Il-Ltiti ea.iti.Ã-tgflta.id outlet otte 824.

The fluid st lie.matic; cÃf"t.he c.as5ett:o 800 5howrt M. FIG. 8 rnay be c,~mbofliGtl. into Vat-iOt.iS c:a4st:tte apparatus. ThtÃ.s, the vfiricÃtÃs embodiments of tlte cassette 800 tlittt include tt 30 fluid tlow-patI~ ~~~~~sctitt'd by tt-ic flzÃici sclit.~matic slit}wÃi in I~IG. S are not the, only cassette eml'_oc3.iMettts that Ã-nay incorporate t1-tis or an alternate embotlimezÃt: o-I'th.is iYLÃicI :;clieÃ-tiati.c, Acldition,ally; tlio types ot vahves, the order of acttÃatioti ol'the valvesõ
and tlie iiumber of pttmps may vary in o~ari<3tÃ.s cassette embocl:imertt:5 L}fÃ13is fluid st.ht,Ytnatic.

2 :.~

S'tÃll referring tc) FIG. 8, the fltiitl enters the cassette, throtiglx fltiict inlet otto 810 -Uld is puiiil)e~.~ t.oeitl.3eg- afint pi:tti-al3 #luid13at1~ 8l2c~rasee,oxidpump klt-idp,.itr~ ~~18. Inone embodiment, ptuaip inlet valves 81.4, 8Ã78al.Ã~.amate:l`~ oper.i and close, andt:l~ic valve 814, 808 that is open at a~iy giveÃi tinic allows the #lti_itl i.nto.its respective fltaiki.pt-th 812, 8.1.8 a~id ilitc?
the respecÃivc, pod l.~unnp 828, 820. The respective pttrnp ii1lct valve, 814, 808 then closes, ~~-id the COrÃCSPODditis:s ~~~~~~ip s}ci-lei- valve 816, 822 opc::ns. The .llciisl iti puÃriped out of the pod puxnp and tbott<gli fluid utit1et oric 824. However, in other er~~bociinicnÃa, both valves 808, 81.4 operi aiid close at the sarne tirrie. ln sc?n1e enik.~odinieni.s, iio valves s~ie. in the cassette.
1.0 A metering pt~~~~~p 830 pumps a voIt.trne of SecL}riti tluid.l-rom a.
sourt;o ccjnnect:etl. tc) the cassette 800. 'l'he metering pump 830 is actuatecl separaie(y from the pod pumps 820, 828, tlius, t~einoterÃng pua~ip 830 can 1~unip at different rates thaii the pod puii:tps 820, 828.
'E'l7e Ã-neteri.n4.~ ~~~~~p 830 ltttti3ps a vnluine ol':~econd fluid from a secozid IlLiicl sotrrce ittto the fluid li~~e at poigtt 826, prior to the fluid exitiÃag tluÃd ~.~Litiet one 824. T}ie source Ãy 1.5 connected to the rneternl.-, lttili3p tlIrnuwb a .i-l{iid lir.~e which intersects the ii-aain fluid path at point 826. 'Valves 832, 836 wo.t-k to puml3 flu.id ~~~i-ii tlie secoi-id sottrc:.e and iiito t}.ie t:ltiid line at poiiit 826, In some eml->odimeiats, the metering puttip 830 is eitlier not use~.~ o.t has a very different pumping pattem f-com the ~.~oti ptimps 820, 828. In tl-ic~
~xeÃnplar~-' eii-ibcpclime:nt., the 20 metering putnp itiel~ides fluid naanagemenà system (FMS) -,,ohnnettic, tneasurement capacity. The reference cbanil~er is located otitside the cassette. In tl~~
exemplary embodimetzt, the seG~~~id fluid c~~~~rce is avial. of liquid cni.ltiected darecÃly to a spike in the cassette. The spike is directly coniieetecl to the fluid liiie. In oÃliÃ~r c-l3-lbodinients, the spike is connected to a tLibe that is coaiiiecierl to the second fltiid source.
'I'?~e vial c:,an contain any "."? Iic~tiid, but some embc?dimetits, contai.Fis a t1~erapetit.Fc liquid such as 1~epiirzri. l-l~~~~ever, in other ertibocliraients, [hesecontl fluid is a ul~enlottteral.~yagent, r.t nutriti.cjr.tal supplement, .iiitibiotic or a~iy other therapeutic whether .nutntionalor riorlnnuÃritive lielui&

The fluid is la~~rnpecl iii.Ã<3 the :f-lt,itl ititet: ~~~ie 810 and to the fluid otttle.t oaiG 824. ln sorne e.tnbc7dinienis, the f`Iuid is 1~Lu~~iped f~~orn asource to a treaÃnient area, wbich is part of'a 30 contir~~ious ~low eircttit* and the13 flows back to the source. In one embodiment, tl-ic. iass~.~tte is tasecl to purnp b1ooc.l frorn a pati.e.n.Ã. through the t'~tiid outlet one 824 which is contiected to a ~.~Iialyzet. The blood theia flows through the dial} zer and ~~ack to tlie patient throi.tg1i a tube.

The embodiments of the flttiti floa,-pathsc hetnatic sliow!.-t iÃx FIC"F. 8 c:RzÃ~ be erzibodierl into <i sit-tic.ta:tre. :(n the exctnplat_y embodiment, the stTu.cture:is a tliree plxite cassette with actuating tiZ~.`n-.ibraraes. Alternate e:.mbot.liniunts of th~,Y
casSGti:c ;:tre, also described below.
Referring now to FI+G:$. 9A a:ticl 913, the ottter side of the top plate 900 of the exemplary s;rnboclfl3lCtlt. OCtllc: Ca4sette is s1:Ãown. T'het.op plate 900 incladc.s oaie half of the pod purrips 820, 828, This half is the liclttici.lial# wht?;rc the sottrce fitaici will flow tl-irottg&i.
Tlz~.~ twti fltiizl paths 818,. 812 are s1~~iwti. These fluid paths ls~ad.tc}
their respective pod purzips 820, 828.
1.0 The pocl pÃtmlas 820r 828 iticltttlc a raise:.tl..l-1ow path 908, 910, The raisGtl. flow path 908, ~ 10 allows for tlte.f(taid to contitit.te to tl or~~.~ through tlie. pod p Lttrtlas 820, 828 after the membr,axre (tiot shmvn) reaches the end. of stroke. TIius, the ralsed flow path 908, 910 mar-iimi:zes t1-ie membrane car.ts.itaw air or tltiid to be t.rappetl. in the pod lnanp 820, 828 or the menibrane l?loc.l;:inqw the inlet or otltlct of the pod pt.tnip 820, 828, which wotiicl zttbzlait 1.5 conti.nuot.ts flow.`I'he raised flow pat[i 908, 910 is shown in the exemp(at.-y embracli.rtiettt having pa.rt.icr.tla.r difrieÃ-tsions, atil in t[-t~ exemplary embocl.inic:nt:, tl-ie c:limeiasiolis are ~.~qtriWtl.011.t tO the f'Itiid flow paths 818, 812. However, ir7 alternate <'z~~botliment,, as seen iaI
FIGS. 18A-1 8lv:, the ra.zsed flow path 908, 9.10 is tiarrower, or iÃx :st.Ãll other embot:timet3t.s, tlic raised flow path 908,, 910 can be a~iv. Ã~:1imei-tsioiis as the purpose is to c:caiitrol fluid flow 20 sota5 toac_hieve a desired flow rate or behavior of the fluid. (Ãx some embodittienÃs, the raised flow path 908,910and the filttid tlow paths 818, 812 have d.it~ereÃ:zt d:imenszons.
Thus, tN-ie dÃmerts.ions -,1-tow.n.,arirl described liere with respect to the raised flo\t prttli, the pod ~.~ti.tiirps, the valves or any othc-t' Ãrspecà are mere exemplary and altemtttc crirl.~ot.liÃtient.s.
Other ertzboclimcttts are rcaclily apparent.
""? In the exemplary et-t3bodii-ricnà of the cassette, the top plate .Ãacludes a spike 902 as well as a container pc:s-cli. 904. Tttc spike 902 is hollow and is fluidly connected to the flow patli_ In some embodiments, a needle is attached itit:o the spike. In other embodiments, a nectll~.~ is co-nnectet.l to the container rtt:tac:htricnÃ- (see :FIG.
1"'t;.=, 1206).
Referring tiow to F TGS. 9C fii3d 9:[), the inside of the top platc.900 iti ;;hown. The 30 raised flow paths 908, 9I0 c.onrtic.t-s to the itil~.tt flow pat:lis 912, 916 tatrÃ,l outlet t~t1w paths :314,91.8 of the pod p-tartps 820,828, 'I't~e raised flow patlx:; are described M ri-zore fietail atlove.

The mcÃering, pt.trtip (taot: shown, shown in F[GS.. 1OC. and. 101)) includes cot4irtet:tit3n to ati aÃr z>ent906as well as ccatincction to t:lie sp.ÃICe's hollow path 9412. I11 the e.~en-1pl.ary ,,,~iv~ 5 ca~~odiatleaat, the air verit 906 iÃic1tad~s an air filter (aiot E17c~Nvn). In the, ~.~xi.'a-a-i Plarv enibodinient, the aff 1:Ã1Ãer is a particle air ~`alter, soniiG.ron hydrop}aobic air filter. rÃi viÃric?tas embodiments, t.hÃ.Y size of the filter tri<zy vary, iaa some irastarices the s.i~e will cl~.F~~:.aa{l t~i3 desired vaat.c:c~.Ã~ie.
"f'1~.~. rais~t~:a'ir:a~ pLaaa~p works b3.
taking air in thrc.`~a:tgh the air veÃià 906, pttÃiipiaa.g the air to the container of secoaad flttitl (aiot showaa) tl-iroxigla t1-ic spike's hollow pfitla9tl2 sÃaad then piamp%.ng a voIurne of second flÃa.id. otÃt of the Coaatainer (not shown) tlirottgh the spike's hollow path 902 and ilito the f7taicl line at poisat 82& T'(iis fltÃizl flow faat.li for the aileteriaag faLiaaip is stiowya with arrows ora FIG. 9C..., Referring Ã~~ow toFIG:S. 1Ã.:ÃA azid 1OBõ the I iquid side of the.Ãi).idf?late 1000 is sllowil.
1.0 T1'ae areas complementary to the #itÃ.id, paths on tla~.a HanÃ.Yr tap plate are s.howr.t. These areas are slig lat.ly raised tracks that present asa.arface finish that is conducive to laser welding, which is tlie mode of anaÃaÃ.itactaare in tbe exemlalaay, embodimeÃit. Tlio.
fla.iid 1Ãilet 810 aald flU.icf o-Litle-t 824 are also shown in this v.iew.
Refierring next to FIGS. I OC:: and 1 OD, the air sÃde. of tlze midplate 1000 is shc+x.vn 1.5 according to the exemplary embodiment. '_I'he air side of the valve faoles 808, 8.1.4, 816, 822 eos-respolid t.o the holes iii the fltaid side of fl-ie midplate (shoxv-n iii RG. 1.Wk). As seeai i.ti FIC& 12C an(l 12D, m~.'$rihr;:anes 1220 coraiplete valves 808; 814, 816. 822 while mea.libaane> 1226 complete pod pumps 820, 828. One embodiment of the valve membrane is shown in FIG. 2E., Additional embociimeaits of the valve membraÃ-ie are shc?wa-i in FIGS, 20 2F-ZG, 'The metering lia:ÃÃaip 830 is cc~~iipleted by membrcllne 1224.
t.~iie embodiment of the iiieterinW,~~ purnp meÃ~.~tt~raale, is shown in FiG. 5F. Other embodiments of the metering ptaÃiip nleÃ.a-iba~,ane aresl~owrz in FIGS. 5l" 5I=1. The val~~e,-, 808, 814, 816, 822, 832, 834, 836aÃ~e actuated paai:_tÃanaÃic.ally, anci as the a~ieÃii1~~raeic is pÃ.alled away from tlic holes, liquid is dra'w~n in, as the rÃ-aca-ail~raaae is pushed toward the }Ãoles. 'I'l.le fluid flow is directed by the opening and cle>sin<f of t1-ae valves 808, 814, 816., 822, 832, 834, 836.

ReI-errirag to FIGS. IOA. and .1OC., ttÃc anet:c.Yriaa~ ptaa-np includes three I-ioIGs 1:0Ã12z 1004, 10()6. One laole 1002 piills air izatc) the metering pL-mp, the seco.ad hole 1004 pushes air to the vi1:ersource c<3ntainer and also, da.-aAvs lltfLiici from the soLirc:e c.o:ÃaÃ-xÃiraer, and th~.a thiÃ-cl hole 1006 pushes the secoÃicl fluid Ca'oaaa the metering pump 830 to the -flaaid line tc:) 30 point 826.
Valves 832, 834, 836 act.Ãaate the second fluid metering pa:flraxp. Valve 832 is the second fluzd~spil;:e ~~~lve, valve, 834 is tbe air valve aaid valve 836 is the valve that controls the flow of f1taid to the fl.taiel tirac to area 826.

Refcrr-ingrtext to FiGS. 11A and 11 B, the 1i1!.ier view of the, bottom plat~!
1100 is showti. The inside, view of the pod purti1~s 820, 828, the nieterin~; 1iurix1) 830 and t1~e vxilves 808, R149 816, 8229 832, 834, 836 ai.tuatiorri'<tir chttri-ibÃ.Yr is shown.
Tl~ic pod pumps 820, 828, r~icterÃng pt.tri-ip 830 titid the vfrlves 8Ã18, 814, 81.6, 822, 832, 834, 836 are ac.ttxtiteci by a pneumatic air sottree. Referring now to 1"ICS. 1 lC atid 1-1 D, the ower sidc of the bottom plate 1100 is showii. The source u#'air is atÃsrched to thi's side of the cassette. [.Ãi. onc.
e~~~bodiment, tttbes contiect to the features oti the vialves aiicl pumps 1102. In swne embodiments, the valves are ganged, ar.id rtiure tliari ot-ie valve is actuated by, the sRzrnc air 1.0 RctcrritZg now to l"rGS. 1 2A and 1 2B, <tnassemblud cassette 1200 with a.
corttaincr: sot.trce ot sect~~id fluid 1.242 attaci~ed.is shown. The container .1202 contains the soitrce of the scc~~~id fluicl and. is attached to the spike (not sl]oo~~-n) by a container attachment 12W The air filter 1.204 iw whowrt attrxc.bcd tt) the air vent (not showrr, shown i.rz F1C_1. 9A as 906). Although not visible in 1^ iCi. l'?A; the container perc1i (s}~owti in FIG. May 904) is 1.5 under eli.c container aÃtachrnent 12Ã16 A.ii exploded view of t1reiassembled cassettc .1.200 showii in PGS. 12A atid 12B is shown in FIGS. 12C:` and 1213. 1;n tl-iesc:
views, Ãhe, ~.~xemplarv embodiment ot'the pod pt7nrip niu~~.~1_iraiies 1226 is stxown. The Gxen-1p1ary etnbodinient includes mcnibn, ties shown in FIGS. 4E atic.l 4F. The gasket o1`the membratze provides a sc.a1 bctsz~c.cn the liqtti~.l chamber (in the, tqp plate 900) and the ztir:"ac:it.tRttioti 20 clia~~iber (in the bottoiai. plate 1100). The dimpled text-Lite oti the do.Ãne of the iiiembraties 1226 prc?vicle; amongst other features, additional space for air and lieltiicl to ~scape, the c1aan:tber at the end of sÃ.rok-e. In other embodimeiits of'tl.lc cassettc, t1re mena.13rartes shown in F1G& :>A. 5t" or 5D may be EÃ.-sed. In alternate ea-iitioclinieFits of the cassette, the niertzbrancs sI-tnwn. in I"W& 6.A-66- may be used. As discussed in greater clctail abnvc, "."? tl-tese memk3g-aties itis:htdc a double gasket 62, 64. Tbe dot-b1e AYasket 62, 64 featu.re wottld be prefc.rrc.tl in cmbodisiZ~.`nts wtacre both sides of the pod pump include liquid or in applicat.iotis where seali.ag 1';;~oÃb cl-rarzibers is desired. In these ctriboditne.Ãns} a rim c:ornplcrnentary to the gasket or other #:cal-ttt-e (not shL}'kvii.) would be aÃ1deÃ1 to t.h~.~ inner t'ottorn platc. 1.100 for the gasket 62 to sea1 the pod ptt.Ã~i p chamber in the bott~~rn plate 1.1.00, 30 Riferritis~ ~~ow to FIG. I 1A; a cross scitic~~ia1 view of the pod pumps 820, 828 in t~io.
cassette is sliowi7. '1`'he details of the attac1rz~~~~ertt o1`t1te znernbrarBe 1226 cartbc seen in t.1tis view. Agairi, in ttte excmplar-y, embodiment, the tiaembratie 1226 gasket Ãs pitic1ie~.-1 bv the niidplate 1000 and the bottom plate 1100. A niin ~i-i the nuc1p1Xi1:Ã.Y 1000 provides a feature fc>r f1-re gasket to seal the pod ptii-tip 820, 828 chamber loÃ.ated.i11 the top plate 9043.

Reforriitg next to FIG. 13B, tltis cross sectional view shows thi.~ valves 834, 836 in tl-ie asseÃ-zibied ~zissette. '1"he menibrane:~ 1220 areshown assembled atiel are held.in place, irI
the c~~rnplar~' oml;iodit-ricti[, by being s<i-iidwichc.Yd b~.at~~~eerl the ri-iitf:plate 1000 atitf, the btstt in plate ! 100.
Referring next to FIG, 13C, this ero-s5 sectional view shows the valves 816.
822 in the assembled cassett~::. `I"l-ic mt:rnbrar~~~ 1224 are shown ~~senahletl and are hel.ci .in place, iri the exemplary embodiment,1~,y beiiig saiidwic,l~ed betrveen tfic iiiidplatc 1000 and the bottom plate 1100.
fZeferring Ã~~ow toFIG:S. 14Ar i4B, ati assembled alterÃxate em1?odi.Ãuent of the 1.0 nietering puttip 1400 is s1-iowii.. fn this ~~bodirr~ent, t:I-ie aneturing pwnp 1400 corir.tec.ts to the cassette (ttot shown), t.hus, it is iiot itttegral witli the cassette.
Referr.ing to FIG. 14A, ttie iiieterinW,~~ pump 1400 inc:.Iudes a top plate 1406 anda fltiÃd C~~~~~ectÃozx to t:}ie c::aysette 1402.
A container 1404.1s s(iowti in the metering ptimp 1400. 'rl~e coritaaner 1404 co.at.ain5 a liquicl second fluid and will be fluidly contiected t:o ttie cassette t~.tiid paths via t:}io fltiid 1.5 connection to the cassette 1402.
Rete.t-rin~; iiext to 1^I~i. 1443, #(~.c ~.~~eterit~~ puiiip 1400 also includes a bottoÃii plate 1408 th~it includes air actuation pori, 1416. Referring riext to FIGS. 14C
~~id 14D, exploded views of the metekic~~ pump is shown. `I'.hemembrai-aeS l4.lOtliat comp(ete the valves in t(ic micl.plate 1412 ar~,~ shown. The assembled tnetering pttl-iip on a c.zts4ette 1414 is 20 shown in H:G, 14E. FI:(:i, 141~ shows a partially assembled meteri-tig pump oti a cassette 1414, where ttie midplate 1408 is not covered by the top, plate 1406.
Refi?rrinW t~ow to:FI{_'rS. 15A-1 5:I), the t.op plate of the alternate eznbc3cl"Ãn~ent of the motiriaig f.~ttmp contains many of the sa:me feattires as secii in the top plate of the exerilplarz' ernboclir~~ent of the caSsette. described above witI-i respect to -the znetering puaup in F l:GS. 9C_ "."? 9I). The a.ir is-iIet 1416 iti some embodimeiit1 hieltide:~ an air I.i.lÃ:er. similzi.r to the embodiments described above. Ref'errisi~~ ~iow tk) FIG..1 SC, C[ic air flow f7ti.id path :is shown with arTows. '1'1-ie air is take.t-i in th:=c~~igh the air hiiet wirl iheii ptisheti towarcis the container (not sbowii.). Reters-ing Ãit3w to FIG. I 5D, thc.Y secotikf fli.ti.tf flow path is shown with ;:~rrow:;.
The SCCODd fl-Liid is ptiiiiped froni the container tncat,.ihcaw.n l and ca-Lit to the cassette at point 30 836. Thus, th~. altemate embodiment of th~.~ meteriis~ puinp shown in FIG$.
14A- 1: C3 is another structural fi-tip(ementation of the t7taid flnw-pat:h schematic ;;hown in F'iG. 8, oai(v ttie meteriÃig ptimp component is not integral with ttie cassette, ratlrea-, attached to tl~e, Ca:ssette.

Retorririg now to FlGS. 16A-16B, the holes indicating the flow path of't1ie.
flÃ.tid ,ar~.~
showri, Relerr.~iÃ-ro riow to F1(.iS. 16tn' arzd 16D, the air side of the midplate I412 is sliowÃr.
T1Z~.~ air sirlc of'tlre valves 832:, 834, 83r`aq izrclr.rtlirrg the mctefirrg pump 830 are sl.row rr. T1;re holes in the valves 832, 834q 836, ~~id tlre r-neiering ptrmp 830 z:csrTespontl Ão the valves around the metering pttml.~ in Ãl-ic schematic s1~owri in FIG. 8, and a1scN in the i:~enil.~lt~rv ernbodirnc.rzt ol`tlze rnidplaie oftl-ie cassette s1iowrr in:FI:GS. 10A-1 0C.
ThLrs> altl.rough. the ~icÃering puriip arid the corresponding va1ve5 ;rrrd flÃzicl lir1~s aac outside of the cassette in this eynbocii.r~~ient,. the valves arici fluid l.irics are similar. Thus, ritrrctt of the descript.iorr above with respect to the exemplary embodiment meÃerin;y pump -feaÃurcs is applicable [~.~

1.0 t.lic! alt~.~rrZate er-a-ibtrciirricrat of'Ãlic metering l.~r.rmp.
Referring r~ow to I~[GS. 17A a'id 17B, the inner bottom plate 1408 is slrcrwii. `I'he correg-)oxi.cliri.vact-trutior.i sides oi'Ãl~e valves 832, 834, 836 and ria.eÃcrirrg tytixia.t) 830 are ShnwÃ-r. Reterrim-, r-iow to FIGS. 17(Y azrd 171), the outer bottom plate 1408 is slaoa,vri with Ãlie ac.trration. ports 1702 whicb providing access for t:lie air to acÃr.rate t:lie metering pr.rmp 1.5 aÃ-rd the valves.
:iq described aliove, the exerii}il~rv embc.sdimerit is one cassette embodiment that incorporates il:rc e:~~~i-iiplary fluid flow-path schematic showr1 in FiCs. 8.
However, t1-tere are altez-riate ernbodÃment> of the cassette that incorporate many of tlxe same fie.,at.rres of the exemplary embodiment, but with a sli;fht.lv dift'~~-rer-it stractrrr-Ã.rl design. One of these 20 alÃerrnite embodiments is the crlibodiriaeÃit shown in F1Ã:& 1SA- 2213-In tlie ulter=riaÃe embodiment sliown in FIGS. 18'A-2213, tl:zc corresponding numbering of the elenicrtts used w.itlt respect Ãr) FIGS. 9A-12I3 apply. The cross sec.ti.orl5 views of FIGS, 22A and 2~'B corre:.s~. rÃ~~ntl to HG& 13A arid 1;>t`.
icSpectively. T13o two eniboclii-nents v.irv only slrght:lv and this variation can best be seen ii-r FI:GS. 1 t3A-.1 S1:: wt.rera "5 compared to the exemplary er-r3bodimer7t in FIGS. 9A 9.E, In particrÃlar, the raised flow path 908,910 on the poclptrmps 82:07828 iar thc ,.rlt~.arrrats.: embodiment of FIC_rS. 18A- l. 8E h;:ts clÃmcnsions that are a smaller than in t1i~ exempla:n~ er-iiborlir-iiezit sho~Nvn in FIG. 9Ar9l:-:.
Additionally, the fl.tric~ paths in the cxerarp.lartJ crrlbodirr:lr<:r.rt of FIGS. 9A-9E lt;.u>entori squared crfCecl<jes, w1-icrezis in the alier`rraÃe ei~~~~odinrc:.nt shown in FIGS. 18A-18E, the f1:iici 30 paths hwv~r:: more rounded et.lges. The exemplary emb~.~clim~.'rrt'a ecigcs being more squared off lend to easier manufacture as the laser welding is more e-t`i=icient and e-k`k`ecÃive izt t:lris embt?di.mertt.

Referring now to F1GS. 23A 27B <tr-iot:l-ie:r xrl.Ã.urn.ate er.rrbot3:itnerzt of t:h~.~ c<zssctte is show.-rr. 1[~~xvever, in tlr.is cmbcrtliri-reziÃ, the metering pump is r~c~t ir~c~c~rl~c~.Ã~t~te~l or i~~te;~;raÃeÃi iiito the cassette. Tbus, in this embodiment of the cassette, wIiere, a in4tc rin<; pul-lip is cleszrecl, a separate metering pttr~ip is con~~ected to the cassette. Oiie embodiment of a sepa_ratc: nletering pEullp is dcsc:ri.l,.3et1 iiritl shown with respect to FIGS. 14A.-1 77D. Man~, of tlic: featrtrc:s. ix.a the pod pumps and i-l.ic: fluid litic:_s Etre s1niilar to the exemplary ernbocliment shown in FIGS. 9A-12D. TliÃas, the description and numbering of the tigtires corresponclitig to FIGS. 9A-:12~ ~~~ii be applied to RCFS. 1-3A-26D, TEic cross sc:ct.i n, views ir.1 the alternate embodiment sl~owii in FIGS. 27A anci. 27B correspond to cross sectional views slio-wii in FIGS. l3A and 13C respectively.
Referring Ã~~ow ioFI(iS.24C; aiicl 24:I), an alternate view of the valves 808, 814, 8.16., 1.0 822 is sliown. Comparing the valves 808. 814, 81.6; 822 in l"[GS. 24C-24D
to t.h~.Y
exemplary embocli~~~ent shown in FIGS. 1OC- 101) as 808, 8.1.4, 816, 822, it is apparent that the valves 808, 814, 816, 822 ift FIGS. -14C-24D itiClucl~ a raised feature 2410, w1iereas tl~e valves 808, 814, 816, 822 in FIGS. l l)C- l fl~) do r.iot:. valves 808, 8I4.
816, 822 shown in FEGS. lO("a 1Ã?D include asmoot:h ct~tistru4tion atid do not iriclticle ~~iy raised or textured 1.5 l`eat :re.s. Referring aaain to I-1t=i& 24C aixl 24I), the raised f=murre 2410 o.f'iE~~e val~~~s, 808,.
8i4, ~16, 822 provides for a dit'feretit sea:lin4? Ã~~echanifi-ni for t:t-ie t'luid flowing from on. e f'lLrid path to th~.~ i-icaxt {wliero each fl'.uiÃ.1 pa th is i3itlicated by the holes iti i1-~e v;.alves 808, 814, 816, 822).
Reforr-iiig now to FIGS, 231A-213B, the alt~,'mate t~~~~boclimet-it of tlxo top plate 900 is 20 shown. A~..ra.iu, comparing tbis alterna.te embod.Ãnient to the exe.Ãiiplar~.,, enibocliment sl3nwtz in FIGS. 9A-9B; in FIGS. 9A and 9B, the tol) plate 900 is one solid part.
:H~.~wever, te.fierr.inM agaiii toF1G.S. 23A-2313_ the top plate 100 is tour separate parts 900a.,900b,900c., 900d. In manufacture, the t~.~Ãar plates are laser welded or tiltrasofliicallv welded iliclivÃdually nsito the t'luicl side of the niidplate (shOW.11 ill Ctff;a& 24Aw~.4:I3).
Other znocles O.('rIM11.ut:ac:ture "5 are d.iseu5se[l above.

ReI-t:rririÃ~ i-iext to .l;IG4. 25.A-25B, thc.a alte:n-iate Ã.Yrnbodiment of Ãhc.a bot.toin plate 1 10tl is sl~~ow.ri.

shown in FIGS. 1 lA-1 lB, in 1=+'.Ct_i-S. l . l A and 1 IB, the botÃ.c.3rn phat.e 1100 is cjrte sol.id par.i.
1=10wc::vc:r, r'c::l:c:rn"110 again to FlG S. ??A ?5B, the k?ottona plttte 1100 is two separate p'ar1.s 30 1 100a, l1U0b. In ~~~nul'aettEre, tt-ic tivo, plates are laser welded or taltg asonic.ally welded itic3.iv.iclually c?t7to ti-ic air side of the midplate (shown in 1FIC6.
24C..24D.). Referring now to FIG. 27A, the ~iitiltia~~~ece construction of the top plat.e 900a, 900b azxcl the bottom plate 1 t00a, 1'lOOb,tre.i-~.~atclil.Z~ showsi. l=`iG. 2"713 ~icl(i.iti.L}~~ally sl3ows t1-.ic: s~.Ypa~i'ate. c:oai.st:ructiotic)f tl-ie top plate I I 00a; 1lfl0b.

5.1 .lwx~,'ruplat`v Embodiments of the 1''timpffi1g Cassette i:n 1~~~actice, the cassette i-iray be tise~,-1 to purrip aiiv ty-pe offlu.ad from any source to any l.ocation. Ti-io types of tiu.id ii-ic.ltÃ_de. nutritive, rionnutritive, incjrgyaraic ct.terni4t:t1.s, or4.~aruc che.tnÃc;a1s, bot3i1.~= fluids or any vtber type of flui.d.
Add.itiona.lly, .t~luid in s~~rne embodiments incltides a gas, thtis, in sÃ~~me embodiments; the cassette is t~sed tt~~ ptarnptt .;a.s.
The c:asseite serves tt) purnpaud (lirec:t the fluld.firom and t the desired Ivcatioris. In some eml.~t.~dimc,nts, t.~Ãitsitie pumps f. ~t:tmp the fltj.ic1. itito the cassette and the cassette -pttmps the flriid out. I=lt~~~~~~~erõ in some t.nibcit.Iir~ie-iits, the pod punafas se,'rve,~ to pti11 the fltiici, iTito the cassette azid pEEiiip t1-ie fluid otit of the cassette.
1.0 As discussed above, deperidisig oiithe valve locations, control of tt.te fluid paths is imparted. `I Iivis, ttte valves being in ti:it`t'ereiit lc:~cat.ioxis or additional valves are aftemate emiaodiÃt~ents of this cassette. Addit:ionally, the fluid li~ies and patlis shoa~~n in the fiiqgurey described above z~~~e f~~ere examples of fliiid lines and path:, Other emf7odifrlellty rnay lt~~~~e more, less and/or clittereÃat fluid pattis. In still ottier embodiments, valves are iicat present in 1.5 ti-ie cassette.
The number of pod ptiÃiips described above .may also vz~.tv depending ., oii the ~.~mboeiimea-it. For example, <z1thoug1-i the exemplary an(i. aItemate embsaclin-ionts shown asid described above Ãttelticle two pod pumps, in ottter embodiÃnents, the cassette inc(udes one, In still other ernbot:ii.i-nents, the cassette includes more t1it~ri t~vo pod.
ptimps. Tb4 podptimps 20 can be single puntpG or work in tandeÃn to provide amnre continuous flow.
Either or botli may be it:~ed in. various embodiments of the cassette.
The t~~-ia-i Ãniet and outlet <~~~e used i.11tercl.lang~able. A, flLiid cai.i flow"in" the ouil.et and"uut" the iiilet. Additional inlets,'Outlet~ ("ports'".) can be added.
Additional ports may t]e provided to i~~ipart particiiI~~~~ fluid patl.is onto the ca:ssette, 'f hese additional ports arenot "."? nezessarav zill used all of tl-ie tiii] e: ii-istead, the varietyof'porls. provide flexilazlitv of Ã_ise of.' the cassette in. practice.
'f'1~e purnpi.a43 cassette car-i be Lisetl in a myriadof'applieation:s, However, i.n oiie t.~~rnpl,try ~rnbodirta~.`nt, the pumlaing cassette is i.ised to ptu~np blood.
froan a. p;.tt.iGnt to a dialyrer outside ot the cassettearad fhen.providt:_ enou~ l.i pur~ipi.ng force for the blood t<) 30 travel tlirough the dialyzer aYid back tÃ~~ the patient throLigii a li~ie outside, of the, c.assette.
'I'1:ie exemplaÃ.yy embodiment includes two pod punip;;, a blood izilet, a blood ~-utlet:
a~~~ a bepariii metering fatinila. '-[`l~e valves are stiaraotli valves is described ~bove wztll respect tc) FIt_i-. 211). fn t1-ic ~xernplary eri~.3odi~~~enÃ-, the pod pt:trnp Inetnbr,:~~~ieis a dimpled riiembraz-ie as shown in FtG, 4:Ew4:[t.
~1 The blond pump cassette supports both doal-nc~edie andsingle-neectle op4ratiol'a.
Wheri operating with two zieedles the chambers take Wr11S.['illidl(' and clel.ivering so the blood flow is e~fet;tively cotZt.iriÃzmt; iti both lirieS. Whei-i operating with a sirigI.e tteedl~.~ tl~:~ie piimp will first .fi:itl. both ptimp chambers through the arierizil line and then tloii~Cr tO the VeRcrtx4 Iine.
Rs;ferrin.t~ ~iow to F TGS. 12C and 1.22D, in the exempla~. enibotliaient, the fluid or blood inlet line is oriented c.`~i-i the bottom 810 and the flriici or blood outlet is (7n the top 824.
Thuts, in practice, the blood pump cassette ttiay be orie.nted, such that iiorsrtal therapy flow is up throu<w:li the ~iuÃ-i~.~~a c~~~at~~zk~ers, exitiz~.4~ at the tc?~~. In this e~~.il~c~~iizx~eiit, substantially all or 1.0 all air entering the blood pump cassett.~.~ is ptished L}rt toward the dialyzer. I-low~.~ver.. M crt14ier embodi.ments, the blood i.11let line is oriented oit the tol).
in this exemplary embodiment, the metering pump is a heparin Iyumpand is a single chamber FMS meter punip tt-iat takes Ã-treas~~~~ed quantitie5 of 1-aeparin from a vial or container a:iid delÃvers it izito the blood circLiit;'fluitl liiie. 'Fliis f'eatur'eallowy the blcaoc;.
1.5 pump cassette to manage the bepar:ir-i prescription.
St?me embc?ditnettts siiav ittcltide att aii` trap within t~ie, tltjid 1i_ftes and`or at least or.ie sonsor element. Th~.~ sensor element can be any sciZsor element having it capability to det:ertnizte aiiy fluid or non tlriiel seztsor data. In otie embodiment; tl-aree sezt.sor elements are iiic(Lrde-d in a sint le fltiici line. In scame en-ibodimeiits, more, than oi-ie flLiid lin~.~ i~icltid~.'s the 20 tIiree setisor e:letiiett.t >, ha the tlir~~ sezisoi, element embodiment, two of the sensor elemeiits are c.onductivit~r sensors and the third sensor ele~iieÃit is a temperature sensnr. The coxic~~ictivit.y se:n:sor e1er.~~~entw <iiirl tetzipe.rature sen5or eI~~~~ents c~~i, be aiiy conductivity or temperature Sf:i'isor i:.le33I.ilt in the art, In ~.lÃ1f', embodlrtli:iit, the cL.~ticil8ctÃvity he11s()r t,:lemc'=I1tS
are graph.ite posts. I:~i otirer er-tibodirnents, the coricl-Lictivitv sellsof elzinents are posts mzide from stainless steel, titatii~im, piatitiu.iii or aiiv other.metal coated to be corrosi ii re: i5tant and still be eIect-rical.ty cc~~-idtict:iv~.~. The conductivity sensor elernunts will include azi eiectr.ical lead tl-iat tra.iismits the probe it7:for.Ãnation to a controller or other device. In oric t.rnbodinient, the tempera.ttt.ro seaisor is a tb~.armu5ter potted in a stainless stee.l. prob~.Y.
F[owe-ver, in alternate e;mbodinieni5, a c i-iii=:=.~iiiiition teTiiperattia-c; and conductivity 4eaSor 30 elements is tised siniiiar to the aiie described in t.c.~~peiidi~~g U.S.
Ptitint Applicaticin ~.'i3tit(od Sei-asor Apparatus Syst:enis, Devices arid N-letliocls filed October 12, 2Ã30"
(D1,K:'t-024XX).
Ina1Ãernate enil;sodiments: there are either tio sensors in t:lie cassette or onIy, a tex~iperature sensor, only one or more conductivity sensors or ot~c or i-nore of another t.yp~.~ of s~.aT~sor.

??

Aithotrgh the blood ptrmp cassette cmboditt-rer1t ltas 6eeri described, other erzibodinients are casil_y discernable. `!"(le rneterirMl D11131D can be used to admin.Ãstcr or ror-iiovc a volÃtt3ic of f-Itricl. Using the FMS, this voltr.nie is rner:tstrrGd.,.rrrÃi th.tts> t:t sr.it'st.rrrdAlly accurate (or near substantially accurate) vÃslr.rrrie of flr:ritl added orrÃ;nrovc.d i.;~
k-nowri. Other enibodimerit:s Ã.~f this ptrnlpiÃ1g cassette ir7cltadÃ:~ use of a different mÃ:.mbrane or an. veÃ'nrotÃiÃ:d rnerrrbrrriw or otl3er rnc.nrbr'rrr.rÃ:s as desÃ:ri.bcd ttbove. Sor~ie of the vari<rtis eri-ibraÃiir~ierits c.`~frhe membrane arc:. ciesr;.ribedttbÃ.~ve: and sht~~~~~i with respect to FIGS. 4Ca CY.
In practice, the cassette may be used tt) pr:rr~ip any type of flÃriÃ1.(=r'on) ariy. source to 1.0 an~, It3cation. The Ãypos of flr.ricl iticltrÃic ri.trtr-tr.vc.Y, nonnutritive, inorganic c:1wanaÃ:a.ls, or'gariic chemicals, boÃlilv tlr.riÃls or a.ztv otlter tvpe of fi'(uÃd.
Additionally, t7uiÃ:t in some emi~odirnents includea gas, thus, in some embodimetits., tlio. cassette is tiseÃ1 to prr:r~ip agas.
The cassette serves to prrrnp atrÃ1 direc:t tt-ie fluid -t`r-otr-i aaiÃi -ta the desired lc3catiÃ>.as. l:ra some embodiments, oÃrtside pr..rriips pErmp the ~~.trid itit~.~ tlio. cassette aÃiÃi the caysette pumps 1.5 tlre .{~-rriÃ( out. fl:c~~~~ever, .in sorne embodiments, the pod prrr-r3~~~ ~en.~e to pu1.1 -tfle I-1miÃi into the cassette and pr.rriip the fluid orrt of the cassette.
Wh.i1Ãm the principles oi'th.c icivzrztioai hLtve bect7 described hÃ.ar=e-in, it is to be t.tr-rcter=,tood by fliose skilled in d.~e aa that this description is ttiade, only by N.vay of example and ttot as a Iirnit~:rtion as tca the scope of the Other embodiments are c:ont4n1platà ci withzri the 20 scope of the present itivertriora inadd:t.iorl to the exe-niplary embodiments sl~~~vnr mtd described herein. MoÃliticatiorts and sulistittiticrris by one of ordinary skill in thewl are considered to be wit.laar-i the scope of the =1 .-y, ~ '1

Claims (20)

1. A pump cassette comprising:
a housing comprising at least one fluid inlet line and at least one fluid outlet line;
at least one reciprocating pressure displacement membrane pump within said housing wherein said pressure pump pumps a fluid from said fluid inlet line to said fluid outlet line;
a hollow spike on said housing; and at least one metering pump, said metering pump fluidly connected to said hollow spike on said housing and to a metering pump fluid line, wherein said metering pump fluid line is fluidly connected to said fluid outlet line.

2. The cassette claimed in claim 1 wherein said reciprocating pressure displacement pump comprising:
a curved rigid chamber wall; and a flexible membrane attached to said rigid chamber wall, whereby said flexible membrane and said rigid chamber wall define a pumping chamber.

3. The cassette claimed in claim 1 further comprising an air vent fluidly connected to said metering pump fluid line.

4. The cassette claimed in claim 3 further comprising an air filter connected to said air vent.

5. The cassette claimed in claim 1 wherein said cassette housing comprising:
a top plate;
a midplate; and a bottom plate.

6. The cassette claimed in claim 1 further comprising a container attachment comprising:
a container support device for receiving and maintaining a container; and a cassette attachment device for attaching to said spike on said cassette, said cassette attachment device comprising a housing and needle inside housing, said needle in fluid communication with said container support device.

7. The cassette claimed in claim 1 further comprising at least one valve.

8. The cassette claimed in claim 7 wherein said at least one valve comprising a valve housing having a membrane, said membrane dividing said housing into two chambers, an actuation chamber and a liquid chamber.

9. The cassette claimed in claim 8 wherein said actuation chamber having at least one aperture and said liquid chamber having at least one aperture.

10. The cassette claimed in claim 9 wherein said actuation chamber comprising two apertures.

11. The cassette claimed in claim 10 wherein said liquid chamber comprising a substantially smooth surface.

12. The cassette claimed in claim 10 wherein said actuation chamber comprising at least one raised feature.

13. The cassette claimed in claim 10 said valve is a volcano valve.

14. A pump cassette comprising:
a housing comprising at least one fluid inlet line and at least one fluid outlet line;
at least one reciprocating pressure displacement membrane pump within said housing wherein said pressure pump pumps a fluid from said fluid inlet line to said fluid outlet line; and a second fluid administering system within said housing comprising:
a metering membrane pump;
a second fluid inlet line for pumping a volume of a second fluid into said fluid outlet line;

a hollow spike for fluid communication of said second fluid into said second fluid inlet line; and an air vent fluidly connected to said second fluid inlet line.

15. The cassette claimed in claim 14 wherein said reciprocating pressure displacement pump comprising:

a curved rigid chamber wall; and a flexible membrane attached to said rigid chamber wall, whereby said flexible membrane and said rigid chamber wall define a pumping chamber.

16. The cassette claimed in claim 14 wherein said housing further comprising:
a top plate;
a midplate; and a bottom plate.

17. A blood pump cassette comprising:
a housing comprising at least one blood inlet line for pumping blood from a patient and one blood outlet line for pumping blood to a dialyzer;

at least two reciprocating pressure displacement membrane pumps within said housing wherein said pressure pumps pump said blood from a patient to said dialyzer;

at least two valves, said valves comprising:
a housing; and a membrane, said membrane dividing said housing into two chambers, an actuation chamber and a liquid chamber, said actuation chamber having at least one aperture and said liquid chamber having at least two apertures and wherein said liquid chamber comprising a substantially smooth surface; and a heparin administering system within said housing comprising:
a membrane pump;

a heparin inlet line for pumping a volume of heparin into said blood outlet line;

a hollow spike for fluid communication of heparin into said heparin inlet line; and an air filter fluidly connected to said heparin inlet line for trapping air.

18. The cassette claimed in claim 17 wherein said reciprocating pressure displacement pumps comprising:

a curved rigid chamber wall; and a flexible membrane attached to said rigid chamber wall, whereby said flexible membrane and said rigid chamber wall define a pumping chamber.

19. The cassette claimed in claim 17 wherein said housing further comprising:
a top plate;
a midplate; and a bottom plate.

20. The cassette claimed in claim 17 wherein said reciprocating pressure displacement membrane pumps comprising a membrane dimpled on at least one surface.