US 3856001 A
This laryngoscope blade has an elongated, transected tube-shape shaft. A major part of the length of the blade is straight and a minor part of the blade is smoothly curved to form a tip which is tapered inwardly. A flange formed by the tube and a lamp are located on the left-hand side of the blade (viewed by a patient). The tube-shape is sufficient to permit an endotracheal tube to be placed in a patient through the blade during intubation.
Description (OCR text may contain errors)
Unlted States Patent 11 1 1111 3,856,001 Phillips Dec. 24, 1974 LARYNGOSCOPE BLADE Primar ExaminerLucie H. Laudensla er 76 I t on 0. Ph 11 ,143 ff Y E 1 men or pittgburgh 2 erson Dr Attorney, Agent, or FirmWebb, Burden, Robinson &
Webb  Filed: Aug. 24, 1973  Appl. No.: 391,462 b  ABSTRACT  U.S. Cl. 128/11, 128/16 I 51 1m. (:1 A6lb l/26 Thls lafyngosmpe blade has elongatedflansecled 58 Field 6: Search 128/11 16,6, 3,4, 5 tube-Shape Shaft A major P of the length of the blade is straight and a minor part of the blade is  References Cited smoothly curved to form a tip which is tapered inwardly. A flange formed by the tube and a lamp are UNITED STATES PATENTS located on the left-hand side of the blade (viewed by a 2,070,820 2/1937 Allyn 128/11 patient) The tube shape is Sufficient to permit an nzg i dotracheal tube to be placed in a patient through the 316431654 2/1972 Felbarg 128/11 blade dumg mmbamn' FOREIGN PATENTS OR APPLICATIONS Germany l28/ll 4 Claims, 7 Drawing Figures PATENIEDUECZMQH I SHEET 1 [LF 2 LARYNGOSCOPE BLADE This invention relates to a laryngoscope blade for use in performing medical procedures in the throat, such as endotracheal intubation.
BACKGROUND OF THE INVENTION Normally, the human larynx acts as a valve, opening to permit air to enter the trachea and lungs and closing to prevent foreign substances from entering the trachea. Under anesthesia, muscle relaxation occurs. Fre-' quently, the larynx fails to prevent substances from passing from the esophagus or pharynx and entering the trachea and the lungs, causing serious complications. To avoid this, in medical procedures where there is a chance of foreign substances entering the trachea,
an endotracheal tube is utilized.
An endotracheal tube is a rubber or plastic tube which may have an inflatable section at the end. The tube is placed into the trachea through the mouth or nose and the end section is inflated in such a way that the trachea is completely closed. Thereafter, oxygen and additional anesthetics are fed to the lungs through the endotracheal tube. The placing of the tube is called endotracheal intubation.
A laryngoscope is a surgical device which is used to properly position the endotracheal tube. It includes a blade which is placed in the mouth and throat to provide visualization of the trachea so that the endotra' cheal tube can be properly placed in the trachea.
In all endotracheal intubations by direct laryngoscopy, the physician must consider: (1 the line of vision obtained with a lighted laryngoscope blade and the exposure of the glottis obtained; (2) the direction of the end of the endotracheal tube at the glottis relative to the long axis of the patients trachea; and (3) the available space for passing an endotracheal tube once the glottis is exposed.
While position and condition of the patient are factors in the procedure, selection of a proper laryngoscope is important. Therefore, a laryngoscope blade which permits visualization of the larynx and intubation of the trachea in the most difficult cases and for the greatest number of patients is extremely desirable.
DESCRIPTION OF THE PRIOR ART The Jackson laryngoscope was probably the first to be described for endotracheal intubation for anesthesia; it is a substantially straight blade having a tubeshaped shaft and a straight tip. A straight blade straightens out the patients airway and generally gives better exposure of the glottis. However, when skeletal contours impose restrictions on exposure, improvement can be achieved only to the extent that the jaw can be lifted. Another disadvantage of the Jackson blade is that a battery connected by wires to the instrument provided electricity to its lamp. Later, Janeway disclosed a blade having a slight curve at the end and batteries for a lamp in the handle. Eversole combined the Jackson blade with batteries in the handle in what is known today as the Eversole blade. Miller developed a laryngoscope blade which had a smaller and curved tip that began about 2 inches from the end, a flange for restricting the tongue, and a lamp for visualization.
More recently, a blade which is curved throughout its entire length has been developed by Macintosh (see US. Pat. No. 2,354,471). The tip of the blade is designed to be inserted between the patients epiglottis and the base of the tongue. However, exposure of the larynx is usually not as adequate as with straight blades and it is not always easy to pass the tube through the exposed glottis. In a patient with a high larynx and protruding teeth, it may be impossible to displace the epiglottis enough to see any part of the glottis.
With the Macintosh curved blade, there is usually an appreciable angle between the directionof the end of the endotracheal tube and the long axis of the patients trachea the more anterior the larynx, the greater the angle and the more difficult the intubation. Usually this requires the use of a stylette to assist in passing the tip of the tube between the cords and advancing it so that the tip of the tube is curved down by the trachea asthe stylette is withdrawn.
In a difiicult intubation, occasionally visualization can be had with the Miller type curved tip blade but impossible with a straight blade. Where the procedure must be done from a comer of the patients mouth to achieve exposure, satisfactory exposure may be obtained with a curved tip blade while only poor exposure is achieved with the straight blade; yet, intubation can be performed with the straight blade but not the Miller type curved tip blade. Although cords have been exposed with the Miller blade, passage of the tube has been obstructed either by the flange on the Miller blade or by its lamp.
SUMMARY ,OF THE INVENTION l have developed a highly versatile laryngoscope blade which combines the best features of the prior blades and I have improved upon them. I have been able to accomplish intubation using the blade according to the invention where other blades have not been successful.
I have .invented a blade for a laryngoscope which comprises an elongated tube-shaped member having a major part of its length substantially straight and a minor part of its length smoothly curved toward the tip. The minor part of the length is also smoothly tapered inwardly toward the tip to provide a tip of smaller cross section than the balance of the blade. With the curved tip according to the invention, soft tissues are displaced, and the endotracheal tube is in 'almost a direct line with the long axis of the trachea. Therefore, with the glottis exposed, it is usually a simple matter to slide the tube along the blade, without a stylette, between the cords and along a straight line into the trachea. While the curved tip of the Miller blade provides'the same direct line, the flange and lamp on the Miller blade obstruct the tube. In the present invention, the tubular shaft serves as a flange to displace the tongue but it does not obstruct passage of the tube, serving rather as a passageway. A lamp is provided at the end of the blade at the bend forming the curved tip and is focused both downwardly and inwardly with respect to the longitudinal axis of the major portion of the blade. The blade is adapted for mechanical and electrical connection to a battery-holding handle, such as that described in von Foregger, U.S. Pat. No. 2,289,226 and others.
BRIEF DESCRIPTION OF THE DRAWINGS A complete understanding of the invention will be obtained from the following disclosure taken in conjunction with the accompanying drawings in which:
FIG. 1 is a perspective view of a preferred embodiment of the invention;
FIG. 2 is an elevation view of the blade shown in FIG. 1; 1
FIG. 3 is a bottom plan view of the blade shown in FIG. 1;
FIG. 4 is an elevation, view of the blade of FIG. 1 taken from the opposite side from FIG. 2;
FIG. 5 is a top plan view of the blade;
FIG. 6 is an end view taken along lines VI-VI of FIG. 4; and
FIG. 7 is an end view taken along lines VII--VII of FIG. 4.
DETAILED DESCRIPTION OF THE INVENTION Referring to the drawings, a blade 10 for a laryngoscope is pivotally connected by means 12 to a battery carrying handle known in the art (not shown). The blade comprises an elongated, transected tube-shaped member having a major portion 14 of its length straight and a minor portion 16 of its length smoothly curved to form a tip 18. The tip is also tapered inwardly, i.e., narrowed, for use in small mouths.
An integral surface, of the tube-shaped member serves as a flange portion 20, which extends along 'substantially the major portion 14 of the blade and is adapted to restrain a patients tongue during a medical procedure. In a preferred form, the blade is approximately 6 /2 inches long of which about 2 inches constitutes the curved portion ending in the blade tip 18.
The tubular shape of the blade permits an endotracheal tube to be passed into the patients trachea through the blade, where desirable.
A lamp 22 is located along the left edge of the tubeshaped member (viewed by a patient) adjacent the end of the portion 20, and the lamp is oriented downwardly and inwardly with respect to the longitudinal axis of the major portion of the blade such that light is directed slightly beyond the curved tip 18. The lamp is electrically connected to the handle by wires embodied in a rib 24 formed along the portion 20 (FIGS. 3, 4) and extending into the means 12, where they are connected to contacts which control the lamp in a manner similar to that disclosed in the von Foregger patent above.
By positioning the lamp on the left, rather than the right edge, as is conventional, in many blades, the tongue can be restricted by the portion 20 and the physician may pass the endotracheal tube in or beside the blade without being obstructed by either the lamp or the flange.
The present blade which includes an expanded tubeshaped member having a major .portion which is straight and a minor portion which is curved terminating in a narrowed tip as disclosed offers the advantages that in most patients a surgical procedure, such as an endotracheal intubation:
l. the blade can expose the patients glottis;
2. the endotracheal tube can be passed through the blade, if desired;
3. the endotracheal tube can be passed through the exposed glottis;
4. the tube can be used in smaller as well as larger mouths; and
5. the lamp is positioned so as not to obstruct the procedure.
In a study of a substantial number of endotracheal intubations, my blade was used on patients from 6 weeks to adulthood. A stylette was used with the blade in less cases with my blade than in intubations performed with the Miller curved tip or the Macintosh curved blade.
Endotracheal intubation performed by direct laryngoscopy using my new blade has proved possible in most difficult cases and for a wide spectrum of patients. The blade has been successfully used with both. general and topical (local) anesthesia in cases where intubation had been unsuccessful with known available blades.
Having described a preferred embodiment of my invention, it may be otherwise embodied within the scope of the appended claims.
1. A laryngoscope blade suitable for perfonning an endotracheal intubation comprising:
A. an elongated, transected tube-shaped member having means on one end for attachment to a handle;
B. a major part of the length of the member being substantially straight and a minor part of the length beginning at a point'approximately two inches from the opposite end of the member being smoothly curved and forming a tip on the opposite end of the member,
C. said opposite end being smoothly tapered inwardly toward the tip such that the blade can be inserted in a patients pharynx and an endotracheal tube can be inserted through the tube-shaped member, and i D. to provide direct visualization of the larynx, a
lamp positioned on the left-hand side of the tubeshaped member (as viewed by a patient) and focused in the direction of the smoothly curved tip.
2. A laryngoscope blade as set forth in claim 1 and including a flange portion formed by the major part of the tube-shaped member for restricting a patients tongue during a medical procedure with the blade.
3. A laryngoscope blade as set forth in claim- 1 wherein the lamp is directed both downwardly and inwardly with respect to the longitudinal axis of the tubeshaped member.
4. A laryngoscope blade suitable for performing endotracheal intubation in a patient comprising:
A. an elongated tube-shaped member having means on one end for attachment to a handle;
B. a major part of the length of the member being substantially straight and a minor part of the length beginning at a point approximately 2 inches from the opposite end of the member being smoothly curved and forming a tip on the opposite end of the member;
C. said opposite end being smoothly tapered inwardly toward the tip such that the blade can be inserted in a patients pharynx and an endotracheal tube can be inserted through the tube-shaped member;
D. a flange portion formed by the major part of the tube-shaped member for restricting the patients tongue; and
E. a lamp positioned on the left-hand side (as viewed by the patient) and directed downwardly and inwardly with respect to the longitudinal axis of the tube-shaped member to focus slightly in front of the tip of the blade to provide direct visualization of the larynx during the intubation.