US2935068A - Surgical procedure and apparatus for use in carrying out the same - Google Patents

Description

May 3, 1960 J. 5. DONALDSON 2,935,068

SURGICAL PROCEDURE AND APPARATUS FOR USE IN CARRYING OUT THE SAME Filed Aug. 4, 1955 4 Sheets-Sheet l ARCTATION 4/ DIAPHRAGM p r A ANEURYSM DIAPHRAGM 2 f I I c3 '41 1,195 I 5 INVENTOR 8' JOHN s DONALDSON C3 TTORNEY y 1960 J. s. DONALDSON 3 SURGICAL PROCEDURE AND APPARATUS FOR USE IN CARRYING OUT THE SAME Filed Aug. 4, 1955 4 Sheets-Sheet 2 LEFT SUB-CLAVIAN ARTERY PULMONARY VEINS as lfJP IBLOOD FILTER 26 25 FIG.4

INVENTOR JOHN DONALDSON inzw TTORNEY yv 1960 J. s DONALDSON 3 SURGICAL PROCEDURE AND APPARATUS FOR USE IN CARRYING OUT THE SAME Filed Aug. 4, 1955 4 Sheets-Sheet 3 IIJIIIIIIIIIIIIIIIIIIIII Ill figmmmnmw l l I0 INVENTOR O N S DQNALDSON ATTORNEY y 3, 1950 J s. DONALDSON 2,935,068

SURGICAL PRdCEDURE AND APPARATUS FOR USE IN CARRYING OUT THE SAME Filed Aug. 4, 1955 4 Sheets-Sheet 4' VIAN ARTERY DESCENDING AORTA 3O CORONARY ARTERY FIGJ4 ATTORNEY JOHIf. DONALDSON SURGICAL PROCEDURE AND APPARATUS FOR USE IN CARRYING ()UT THE SAME John Shearman Donaldson, Chatharn, NJ. Application August 4, 1955, Serial No. 526,509

1 14 Claims. Cl. 128-348) This invention relates to the art of surgery and, more particularly, to an improved and simplified surgical procedure for by-passing a portion of the blood circulatory system of a living human being or lesser animal having a similar circulatory system and to provide apparatus for use in carrying out such procedure.

It has been recognized for many years that various ailments and conditions of theblood circulatory system, which are detrimental to the well-being of an individual, may be successfully alleviated, corrected or rectified, provided that the involved portion or portions of the circulatory system are temporarily isolated from the remainder of the system for a sufficient length of time to permit requisite treatmentor surgery while not unduly jeopardizing the life of a patient.

It is essential that certain vital organs, such as the brain, be adequately supplied with blood. If the blood supply is interrupted for an appreciable length of time, a person can not live. Hence, it is of utmost importance, in by-passing a selected portion of the circulatory system, that necessary connections be made within safe time limits. Present-day procedures and techniques require interruption of blood fiow to vital organs for longer than safe time intervals while by-pass connections are being made and, for this reason, are generally not used.

My instant invention eliminates the difficulties experienced heretofore as will be evident to persons skilled in the art from the detailed description appearing further along herein.

A principal object of the invention is to provide an improved, simplified and safe surgical procedure for bypassing a portion of the blood circulatory system of a living human being or lesser animal having a similar circulatory system. 7

Another principal object of the invention is to provide novel and improved apparatus that may be advantageously used in carrying out a surgical procedure of the character indicated. Another object of the invention is to provide a cannular surgical instrument that has improved features of design and construction and that is adapted to be easily and quickly inserted in and form an adequate connection with a selected portion of a blood vessel, such as an artery or a vein.

A further object of the invention is to provide a cannular surgical instrument that may be readily assembled, adjusted, or dismantled, as required, without the use of tools.

A still further object of the invention is to provide an instrument of the type indicated that is simple in design, that is sturdy in construction, that is reasonable in manufacturing cost, that is adapted to be sterilized and that is capable of performing its intended functions in an entirely satisfactory manner.

The enumerated objects and additional objects, together with the advantages of the invention, 'will be apparent to persons trained in the art from the following detailed description and the accompanying drawings which re- 2,935,% Patented May 3, 1960 spectively describe and illustrate several forms of apparatus embodying the invention and several specific manners of practicing the invention.

In the drawings wherein like reference characters denote corresponding parts throughout the several views:

Fig. l is a schematic view of the heart and several arteries of a human beings blood circulatory system, the descending aorta being shown as extending through the diaphragm and the direction of blood fiow through certain arteries being indicated by corresponding arrows;

Fig. 2 is similar toFig. l and illustrates the manner of by-passing a coarctation in the aorta in accordance with the invention;

Fig. 3 is also similar to Fig. 1 and illustrates the manner of by-pa ssing an aneurysm in the descending aorta in accordance with the invention;

Fig. 4 is a partly diagrammatic view of a human heart together with several principal veins and arteries of a blood circulating system, and illustrates one arrangement of apparatus in accordance with the invention operably connected to the pulmonary veins and in the course of being connected to the leftsubclavian artery;

Fig. 5 is a view in front elevation of a cannular surgical instrument constructed in accordance with the invention;

Fig. 6 is a' view in side elevation as viewed from the right of Fig. 5;

Fig. 7 is an enlarged fragmentary view taken along line 7-7 of Fig. 6;

Fig. 8 is a top plan view of the instrument shown in Fig.5;

Fig. 9 is a view in enlargement taken along line 9-9 of Fig. 8; I

Fig. 10 is a view taken along line 10-10 of Fig. 9;

Fig. 11' is a view taken along line 11- 11 of Fig. 9 and illustrates another form of detent means for retaining the rotary shaft in operative position in the body member of the instrument;

Fig. 12 is a similar to Fig. 4 and illustrates a modified form of the invention;

Fig. 13 is an enlarged view of one of the cannular surgical instruments shown in Fig. 12;

Fig. 14 is a view in enlargement taken along line 1414 of Fig. 13;

Fig. 15 is a view in enlargement taken along line 1515 of Fig. 13;

Fig. 16 is an enlarged central vertical cross sectional view through the lower portion of the instrument shown in Fig. 13 and illustrates certain of the parts in another relative position; and

Fig. 17 is a view taken along line 17-17 of Fig. 16.

Referring initially to Fig. 4, a system of apparatus or conduit means, generally indicated bynumeral 20, is adapted to by-pass a portion of the blood circulatory system that is partly shown in that figure. Conduit means 20 comprises a plurality of cannular surgical instruments C1, C2 and C3, aheart pump 21 having aninlet 22 and anoutlet 23, and ablood filter 24 having aninlet 25 and anoutlet 26. Instruments C1 and C2 are connected by aconduit arrangement 27 toheart pump inlet 22. This conduit arrangement includes a Y-shaped fitting 28. One branch offitting 28 is connected to instrument C1 by a section oftubing 30, a second branch of the fitting is connected to conduit C2 by a section of tubing 31 and the third branch of the fitting is connected to the pump inlet by a section oftubing 32. communica-' tion is established'betweenheart pump outlet 23 andblood filter inlet 25 by a section oftubing 33.Outlet 26 of the blood filter is in turn connected to instrument C3 by a section oftubing 34.Tubing sections 30 through 34 may be made of any one of a variety of flexible materials including rubber and certain polyvinyl thermoessence plastics, such. as copolymers of vinyl chloride and vinyl acetate, or polyethylene, which are particularly well suited for the purposes of this invention.

Instruments C1, C2 and C3 are preferably identical in design butmay diflfer in size. Thus, instruments C1 and C2 may be of a smaller size than instrument C3 since the internal diameters of the pulmonary veins to which instruments Cland C2 are connected are less than the corresponding diameter of the left subclavian artery to which instrument C3 is being connected.

Blood pump 21 may be of conventional construction. Similarly,blood filter 24 may be of any suitable type, presently available. The function of the blood filter is to remove air, blood clots or other undesirable material that may be entrained in the blood prior to transmitting blood by conduit means 20 into. the left subclavian artery.

Reference is next had to Figs. through for an understanding of the construction of instrument C1, it

. being understood that instruments C2 and C3 are of like Instrument 01 includes a body member, made of a suitable metal and having a pair of merging construction.

bores 36 and 37 formed therein. As is shown in Fig. 11,

bore 37 is at a slight angle to bore 36. A first tubular as indicated at 41 to facilitate insertion into a blood ves-:

sel. The juncture oftubular members 38 and 40 define anopening 42.Body member 35 andtubular members 38 and 40 constitute a generally L-shaped conduit.

A thirdtubular member 43 is telescopically positioned intubular member 40 and forms a liquid-tight fit therewith.Member 43 has inclined inner and outer end surfaces as indicated at 44 and 45 (Fig. 9). Aport 46 is formed in thewall oftubular member 43. When the parts are in the relative position shown inFigs. 7 and 9,tubular member 43 communicates withtubular member 40 and also communicates withopening 42 and the interior'of tubular member 38 'by way ofport 46. Upon predeterminedmovement oftubular member 43 toward the left, as viewed in Figs. 7 and 9,port 46 will be placed out of alignment withopening 42 and a portion of the wall of the tubular member will be disposed across opening 42 to thereby prevent flow past that openmg.

Tubular member 43 is provided with a series ofteeth 47 that constitute a rack. The rack is adapted-to cooperate with devices that will now be described toefiect sliding movement oftubular member 43 with respect totubular member 46. Such devices comprise arotary shaft 48 that "is mounted inbore 37, 'apinion gear 50 at the inner end of the shaft and meshing withteeth 47,

and aknurled operating knob 51 at the outer end of the shaft. The shaft has an annular groove 52 (Fig. 9). Ascrew 53 is removably secured tobody member 35 and is provided with apin extension 54 that registers withannular groove 52. It will be apparent thatpin 54 permits rotary movement of the shaft but prevents longitudinal movement of the shaft relative to the body member. It will also be apparent that rotation of the shaft through the medium of operatingknob 51 will, by virtue of the described rack and pinion arrangement, efiect corresponding sliding movement oftubular member 43 relative totubular member 40.

Fig. 11 illustrates certain parts of a surgical device which is the same as that shown in Figs. 5 through 10 except that it utilizes a spring-pressed detent means 55 inlieu ofscrew 53 andpin 54 for releasably maintainingshaft 48 in operative position in the body member. Means 55 comprises aleaf spring 56 that is aflixed at one end to the body member by screws or the like 57. Se-

cured to the other end of the leaf spring is adetent pin 58 that is slideable in abore 59 in the body member. As shown,spring 56 normally and yieldingly maintainspin 58 in registry withannular groove 52. The spring may be flexed toward the left as viewed in Fig. 11 to effect disengagement of the pin from the shaft and permit withdrawal of the shaft frombore 37 when the instrument is dismantled for purposes of sterilization.

Fig. 4 illustrates, in part, the manner of utilizing conduit means 20 for the purpose of by-passing the left auricle and left ventricle of the heart. Cannular instruments C1 and C2 are shown as being operatively connected to corresponding pulmonary veins.

The manner of connecting'cannular instrument C3 to the left subclavian artery will now be described. A pair ofsurgical clamps 69 is applied in spaced relation to a selected portion of the artery thereby temporarily terminating flow of blood through that artery. A transverse slit is next formed in the artery intermediate the clamps.

Tubular member 43 having been earlier retracted intubular member 40, the latter is inserted in the artery through the slit after whichshaft 48 is rotated to protracttubular member 43 into the artery in a direction down stream of normal blood flow.Tubular member 40, the joining parts of this tubular member andbody member 35, andtubular member 43 areof such size and configuration as to form a snug fit with the engaging parts of the artery wall. if necessary to insure against bleeding, tape may be applied in the region of the slit after insertion of the cannular device in the artery. It will be noted that an additionalsurgical clamp 60 is applied totubing section 34 to prevent flow of blood from the artery into conduit means 29 while the connection is being made. Upon completion of the connection which, by the way may be made very quickly, the clamps on the subclavian artery are removed allowing blood to flow through that artery and throughtubular members 40 and 43 but not through conduit means 20.

Connections between cannular instruments C1 and C2 and corresponding pulmonary veins are made in the same manner as the connection between cannular instrument C3 and the left subclavian artery. At the times that instruments C1 and C2 are connected to'the pulmonary veins, a clamp is applied totubing section 32. With instruments C1, C2 and C3 connected to corresponding veins or arteries and withclamps 60 applied to only the conduit means, as shown in Fig. 4, blood ilow through the system will be normal. By-passing the left side of the heart may now be quickly accomplished 'by applying suitable clamps to the pulmonary veins and the left subclavian artery at points between the corresponding cannular instruments and the heart, thereby interrupting lood flow into or from the left side of the heart, and by substantially simultaneously removing the clamps fromtubing sections 32 and 34 and placing the blood pump in active service. All or selected parts of conduit means 24}, such astubing section 34, may be primed 'with whole blood prior to completing the by-pass procedure.

Figs. 13 through 17 illustrate ajmodified form of cannular surgical instrument C5 for use in a conduit means 65 that is adapted to by-pass a portion of the blood circulatory system, as shown in Fig. 12. Conduit means 65 is preferably the same as conduit means 20, except that it employs a pair of surgical instruments C5; in place of instruments C1 and C2.

Instrument C5 comprises afirst conduit 66 that is L-shaped, as shown in Fig. 13, and that comprises :1 rectilinearfirst part 67, a rectilinearsecond part 68 and acurvedthird part 69intermediate parts 67 and 68.Conduit 66 has a throughopening 70 in the region of the juncture ofparts 68 and 69. A,resilient tongue 71 having an inwardly projectingteat 72 is struck from conduit first part 67 (Figs. 15 and 16).

Atubular member 73 forms a liquid-tight slide fit with conduitfirst part 67. This tubular member has a plurality of axially spaced externalannular grooves 74, 75 and 76 and includes a taperedouter end portion 77 that has a rounded tip to facilitate entry into a blood vessel and prevent damage to body tissue with which it may come in contact. As is best shown in Fig. 16,teat 72 is adapted to register with any one ofannular grooves 74, 75 and 76 whereby to releasably maintaintubular member 73 in selected longitudinal position relative to conduitfirst part 67.

Conduit part 68 is provided with a pair of diametricallyopposed end notches 80 and carries aspring detent 81. This detent includes aleaf spring 82 that is secured at its lower end toconduit part 68 by screws or the like 83 and that carries adetent pin 84 at its upper end.

Asecond conduit 85 is positioned inconduit part 68 and forms a liquid-tight sliding fit therewith.Conduit 85 has an inclinedlower end surface 86. The upper end portion ofconduit 85 is of reduced diameter as indicated at 87 in order that it may be readily inserted intubing section 30 of the conduit means.Conduit 85 carries aknurled collar 88 by which it may be gripped to effect sliding movement with respect toconduit 66. C01-lar 88 has an externalannular groove 89 that is adapted to receive the free end ofdetent pin 84 whereby to releasably maintainconduits 66 and 85in the relative position shown in Fig. 13.Collar 88 also has a pair of extensions orkeys 9%) that are adapted to register withcorresponding notches 80 upon release of detent means 81 1 and downward movement ofconduit 85 relative toconduit 66. Whenconduit 85 is in its lowermost position relative to conduit 66 (Fig. 16), it extends across and prevents passage of blood or other liquid throughopening 70. At such times,detent pin 84 engages the upper end ofcollar 86 to prevent accidental upward movement ofconduit 84 with respect toconduit 66.

Turning again to Fig. 12, conduit means 65 includes a cannular surgical instrument C3, earlier described, that is shown as being operatively connected to the left sub-v clavian artery. The conduit means also includes a pair of surgical instruments C5, only one of which is shown in Fig. 12. As illustrated, instrument C5 projects through anopening 91 in the wall of the left auricle of the heart and into a pulmonary vein; andopening 70 is positioned within the auricle.Conduit 66 is taped, by use of a purse string, to the portions of the heartwall defining opening 91 as indicated at 92 to prevent bleeding. The pulmonary vein is similarly taped, as indicated at 93, to prevent seepage of blood between the outer surface ofinstrument 66 and the inner surface of the pulmonary vein.

At the time instrument C5 is disposed in the heart, as shown in Fig. 12, its parts are in the relative position shown in Fig. 13, that is,conduit 85 is in its raised position relative toconduit 66 to permit blood supplied by the pulmonary vein to enter the auricle. When the physical connections between conduit means 65 and the blood vessels have been completed,conduit 85 is moved downwardly inconduit 66 to closeopening 70 and the clamps are relocated to permit blood flow through the conduit means and the selected veins and artery thereby by-passing the left auricle and ventricle. It is believed that the manner of practicing the invention with the use of a conduit means including cannular surgical instru 'ments C3 and C5 will be readily understood from the foregoing taken in conjunction with Fig. 12 without further description.

Fig. 2 illustrates the use of a conduit means 94 for by-passing a coarctation in the descending aorta. This conduit means comprises a pair of cannular surgical instruments C3 and a flexible tube 95connected thereto. Upon completion of the physical .connections between the conduit means and the indicated arteries, clamps 96 are applied to the aorta to opposite sides of the coarctation, as illustrated. This allows the blood to by-pass the coa'rctation. The surgeon then removes the restricted portion of the artery between clamps, after which the clamps and the conduit means are removed permitting resumption of normal blood flow.

If desired, the coarctation may be bypassed, with the aid of conduit means 94, by inserting one of the instruments C3 in an upper artery and the other instrument C3 in a branch of the descending aorta below the diaphragm and connecting the instruments byflexible tube 95, as indicated by the broken line in Fig. 2. Obviously, other portions of the blood circulatory system may be by-passed by the use of conduit means constructed in accordance with this invention.

Fig. 3 illustrates the use of conduit means 94 for the purpose of by-passing an aneurysm in the descending aorta. The procedure followed here is similar to that in by-passing the coarctation shown in Fig.2.

From the foregoing, it is believed that the procedure and apparatus for practicing my present invention will be readily comprehended by persons skilled in the art. It is to be clearly understood, however, that various changes in the sequence of procedural steps and in the apparatus herewith shown and described may be resorted to without departing from the spirit of the invention as defined by the appended claims.

I claim:

1. In a cannular surgical instrument, a first conduit having an inlet that is adapted to be inserted into a blood vessel, an outlet and an opening intermediate the inlet and the outlet, a second conduit slideable in the first conduit and communicating with said inlet and said opening, and, means for moving the second conduit in one direction along. the first conduit to dispose a portion of the second conduit across saidv opening and prevent the fiow of blood past said opening.

having an inlet that is adapted to be inserted into a blood vessel, an outlet and an opening intermediate the inlet and the outlet, a second conduit open at each end, slideable in the first conduit and communicating with said inlet and said opening, and means operable from the exterior of the first conduit for moving the second con duit in one direction along the first conduit to dispose a portion of the second conduit across said opening and prevent the flow of blood past said opening.

3. A surgical instrument according to claim 2 wherein the referred-to means comprises a rack carried by the second conduit and a pinion carried by the first conduit and meshing with the rack.

4. A surgical instrument according to claim 2 wherein the second conduit extends beyond the outlet of the first conduit.

5. In a cannular surgical instrument, a first conduit comprising a first tubular member and a second tubular member connected to and projecting beyond one side of the first tubular member, said second tubular member having a through passage and being adapted to be inserted into a blood vessel, the juncture of the first and second tubular members defining an opening that establishes communication therebetween, a second conduit comprising a third tubular member slideable in the second tubular member and communicating with the second tubular member and the opening, and means for moving the third tubular member in one direction along the second tubular member to dispose a portion thereof across the opening and prevent the flow of blood past the opening.

6. In a cannular surgical instrument, a generally L- shaped first conduit comprising a first tubular member and a second tubular member connected to and projecting beyond one side of the first tubular member, said second tubular member having a through passage and being adapted to be inserted into a blood vessel, the juncture of the first and second tubular members definingan opening that establishes communication therebetween, a second conduit comprising a third tubular member have 7 ing a through passage and forming a substantially liquidtight sliding fit with the second tubular member, said third tubular member communicating with the second second tubular members defining an opening that establishes communication therebetween, a second conduit comprising a third tubular member slideable in the sec ond tubular member and communicating with the second tubular member and the opening, and means for moving the third tubular member in one direction along the second tubular memberto dispose a portion thereof across the opening and prevent the flow of blood past the opening, said means comprising a rack carried by the second conduit and a pinion carried by the first conduit and meshing with the rack.

8. In a cannular surgical instrument, a generally L- shaped first conduit comprising a first tubular member and a second tubular member connected to and projecting beyond one side of the first tubular member, said second tubular member having a through passage and being adapted to be inserted into a blood vessel, the juncture of the first and second tubular members defining an opening that establishes communication therebetween, a second conduit comprising a third tubular member having a through passage and forming a substantially liquidtight sliding fit with the second tubular member, said third tubular member communicating with the second tubular member and the opening, and means for moving the third tubular member in one direction along the second tubular member to dispose a portion thereof across the opening and prevent thefiow of blood past the opening, said means comprising a rack carried by the second conduit and a pinion carried by the first conduit and meshing with the rack.

9. In a cannular .surgical instrument, a first conduit comprising a body .member having a bore formed therein, a first tubular member connected to the body member and a second tubular member connected to the body member and projecting beyond one side of the first tubular member, said second tubular member having a through passage and being adapted to be inserted into a blood vessel, said first and second tubular members joining and defining at their juncture an opening that establishes com munication the'rebetween, a second conduit comprising a, third tubular member slideable in the second tubular member and communicating with the second tubular member and the opening, and means for moving the third tubular member in one direction along the second tubular member to dispose a portion thereof across the opening and prevent the flow of blood past the opening, said means comprising a rack carried by the second conduit, a rotary shaft positioned in the bore, a pinion afiixed to the shaft and meshing with. the rack and releasable means permitting rotary movement of the shaft andpreventing axial movement thereof.

10. In a cannular surgical instrument, a generally L-shaped first conduit comprising abody member having a bore formed therein, a first tubular member connected to the body member and a second tubular member connected to the body and projecting beyond one side or" the first tubular member, said second tubular member ing that establishes connection therebetween, a second conduit comprising a third tubular member having a through passage, said third tubular member forming a liquid-tight sliding fit with the second tubular member and communicating with the second tubular member and the opening, and means for moving the third tubular member in one direction along the second tubular memher to dispose a portion thereof across the opening and prevent the flow of blood past the opening, said means comprising a rack carried by the second conduit, a rotary shaft positioned in the bore, a pinion aflixed to the shaft and meshing with the rack and releasable means permitting rotary movement of the shaft and preventing axial movement thereof. I

11. In a cannular surgical instrument, a first conduit having a through passage and comprising rectilinear first and second parts and a curved third part intermediate the first and second parts, said conduit having an open ing in the region of the juncture of the second and third parts, said opening establishing communication between said passage and the exterior of the first conduit, a second conduit slideable in and forming a substantially liquid-tight fit with the second part, said second conduit having a through passage communicating with said passage in the first conduit and said opening and means for moving the second conduit in one direction relative to the first conduit to dispose a portion of the second conduit across said opening and prevent the flow of liquid past said opening.

12. In a cannular surgical instrument, a generally L-shaped first conduit having a'through passage, said con duit having an opening intermediate its ends, said opening establishing communication between said passage and the exterior of the conduit, a second conduit slideable in and forming a substantially liquid-tight fit with the first conduit, said second conduit having a through passage communicating with said passage in the first conduit and said opening, and means operable from the exterior of the first conduit for moving the second conduit in one direction relative to the first conduit to dispose a portion of the second conduit across said opening and prevent the flow of liquid past said opening.

13. In a cannular surgical instrument, a generally L-shaped first conduit having a through passage, said conduit having an opening intermediate its ends, said opening establishing communication between said passage and the exterior otthe conduit, a second conduit slideable in and forming a substantially liquid-tight fit with the first conduit, said second conduit extending outwardly beyond one end of the first conduit and having a-through passage communicating with said passage in thefirst conduit and said opening, means operable from the exterior of the first conduit for moving the second conduit in one direction relative to the first conduit to dispose a porion of the second conduit across said opening and prevent the flow of liquid past said opening, and means for limiting movement of the second conduit relative to the first conduit in at least one direction.

14. In a cannular surgical instrument, a generally L-shaped first conduit having a through passage, said conduit having an opening intermediate its ends, said opening establishing communication between said passage and the exterior of the conduit, a second conduit slideable in and forming a substantially liquid-tight fit with the first conduit, said second conduit extending outwardly beyond one end of the first conduit and having a through passage communicating with said passage in the first conduit and said opening, means operable from the exterior of the first conduit for moving the second conduit in one direction, relative to the first conduit to dispose a portion of the second conduit across said opening and prevent the flow of liquid past said opening, a tubular member slideable in and, extending outwardly .beyondtheother end ofv the first conduit and References Cited in the file of this patent UNITED STATES PATENTS Hollins July 18, 1911 OTHER REFERENCES The Mechanical Heart-Lung System-1., Jongbloed M.D., from Surgery, Gynecology and Obstetrics, Dec. 19, 1949. (Copy in Div. 55.)

Experimental Procedures for Entry into Left Heart from Annals of Surgery, Dec. 1951, vol. 134 #6. (Copy in Div. 55.) V Total Cardiac By-Pass in Humans Utilizing a Pump and Heterologous Lung Oxygenator (Dog Lungs), Campbell, Crisp and Brown, from Surgery Aug. 1956. (Copy in Div. 55.)

Experimental Cardiac Surgery, Surgery, vol. 31, No. 1, January 1952, pp. 146-153. (Copy in Div. 55.)

Mahorner: The Treatment of Aortic Aneurysms, Surgery, Gynecology and Obstetrics, vol. 100, pp. 110- 111. (Copy in Div. 55.)

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