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A SINGLE-PUMP BUBBLE OXYGENATOR
621
Preliminary
Communication
A SINGLE-PUMP BUBBLE OXYGENATOR THE deliberate foaming of blood as a means of oxygenation was described by Schroederin 1882, but the principle was not applied to extracorporeal circulation until 1956. The description by De Wall et al.,2 of a disposable bubble oxygenator coupled with the fixedlow-flow principle, developed in their cross-circulation work, has been followed by a series of modifications of the apparatus. 3-6 We record here some further modifications which have evolved in the course of our experimental 7and clinical experiences and which have been dictated by the need for simplicity and economy.
With such aspiration, adherence of the caval walls to the orifices of the catheters often interfered with venous return. We have got over this difficulty by using gravity drainage into a venous reservoir-which has incidentally simplified adjustment of the pumps during bypass. We have found it possible to eliminate the venous pump and to rely on gravity to return the venous blood to the reservoir and thence to the oxygenator column. The whole apparatus is lowered so that the top of the oxygenator column is below the level of the right atrium (fig. 1). CARDIOPULMONARY
BYPASS
SURVIVAL EXPERIMENTS AND ONE
________________DRAINAGE
USING
GRAVITY
PUMP
APPARATUS
In the original circuit2 the venous blood was from the venæ eavx directly to aSigmamotor
aspirated ’ pump.
1. Schroeder, v. N. Arch. exp. Path. Pharmak. 1882, 15, 364. 2. De Wall, R. A., Warden, H. E., Gott, V. L., Ziegler, N. R., Varco, R. K., Lillehei, C. W. Surg. Clin. N. Amer. 1956, 36, 1025. 3. Gammelgard, R. A., Husfeldt, E., Therkelsen, F. Acta chir. scand. 1957, 112, 439. 4. Gott, V. L., De Wall, R. A., Paneth, M., Nazhi Zuhdi, M., Weirich, W., Varco, R., Lillehei, C. W. Thorax, 1957, 12, 1. 5. Cooley, D. A., Belmonte, B. A., Latson, J. R., Pierce, J. F. J. thorac. Surg. 1958, 35, 131. 6. Giannelli, S., Jr., Molthan, N. F., Best, R. J., Dull, J. A., Kirby, C. K. ibid. 1957, 34, 563. 7. Taylor, D. G. Guy’s Hosp. Rep. 1958, 107, 100. 8. Taylor, D. G. Cavanagh, J. B. Unpublished.
Elimination of the blood trauma.
venous
pump
removes a source
of
Under experimental conditions in our laboratory, a single T6S sigmamotor pump set at an output of 1 litre per minute, with a priming volume of 1 litre of dog blood, will produce 50-70 mg. of free hxmoglobin per 100 g. of blood after 1 hour. With a priming volume of 2 litres, and a flow of 2 litres per minute for 1 hour, it will produce 200-250 mg.
To reduce the blood damage we have substituted for the sigmamotor pump a commercially available BritishmadeMono’ pump, which utilises the archemedian The use of this pump has a sound screw principle. theoretical basis9 and it has given excellent results in our hands (see table).
gives a continuous flow of up to 6 litres per minute and maintain a constant output against a head of pressure of 90 feet of water. A standard production model B15 has been used, but sterile assembly of the unit has introduced some difficulties. The manufacturers are now developing a unit which can be easily autoclaved and assembled. At present the pump is driven by a ¼ h.p. single-phase 240-volt A.c. motor of 960 r.p.m. through a Kopp ’Variator’ to give a range of output from 700 to 5000 ml. per minute. The coronary-sinus return is collected in an evacuated reservoir of conventional type maintained at a negative pressure of 3 cm. of mercury by a separate suction pump. From the bottom of this reservoir the blood is pumped by a hand-operated roller pump to the venous reservoir. The circuit is primed by sucking filtered blood into the coronary-sinus reservoir and pumping it into the venous reservoir (fig. 2). The oxygenator column has an internal diameter of It
Fig. 1—Showing the relation between the pump oxygenator and the Patient.
Fig. 2-Showing coronary
sinus return to either the connecting tube reservoir and oxygenator or direct to venous reservoir (inset). The system can be primed through the venous The lead from coronary-sinus or coronary-sinus reservoirs. reservoir to external suction is not shown.
between
venous
can
9. Hall, J. E., James, P. A., Lucas, B. G. B., Waterson, D. J.
1958, 13, 1.
Thorax,
622
1½ in. has
an
and the tube connecting it to the internal diameter of 1/2 in.
venous
Russell Brock, whose continued support and encouragement have made this work possible.
reservoir
M. H. CASS *
RESULTS
This simplified circuit has been used on ten dogs and there have been seven survivors. In the first experiment a filter was not used but in the remainder one has been incorporated in the base of the helix. The amount of debris found on the filter at the end of each bypass has varied considerably, for no apparent reason. In the sixth experiment there was insufficient blood to prime the circuit and the operating level in the helix was around 200 ml. There should be at least 1 minute’s flow volume in the helix to reduce the possibility of micro-bubbles being drawn into the arterial line. The seventh dog died from a pulmonary embolus arising from the right atrial appendage. A clamp had been applied to the appendage and two purse-string sutures inserted 20 minutes before
Thoracic Surgical Unit, *
M.B. Sydney D. N. Ross M.B., B.SC. Cape Town, F.R.C.S. D. G. TAYLOR M.B. Belf., F.R.C.S.
Guy’s Hospital, London, S.E.1 During tenure of medical postgraduate training fellowship of the University of Sydney. Present address: Royal Children’s Hospital, Melbourne, Australia.
Reviews of Books Doctor and Patient in Soviet Russia MARK G. FIELD, PH.D., with a foreword by PAUL D. WHITE,
Cambridge, Mass.: Harvard University Press. London: Oxford University Press. 1958. Pp. 266. 40s.
M.D.
Dr. Field has spent only a month in Russia, but at the Russian Research Center at Harvard University he has made The apparatus used in clinical cases has now been a long study of Soviet books and journals, has interviewed modified similarly. Two patients (a tetralogy of Fallot many doctors who have left Russia, and has analysed answers and a ventricular septal defect) have been operated on to a questionary addressed to 1650 former Soviet citizens. His using the modified oxygenator circuit and a single sigma- book is described as a study not of Soviet medicine but in the motor pump. The patient in whom the ventricular septal sociology of the medical profession; but as such it is the most defect was closed is alive and well. The patient with penetrating commentary on medical Russia that we have seen. tetralogy of Fallot died 24 hours after attempted complete Soviet medicine provides, he says, almost the extreme example correction. Consciousness was regained and death is not of interference with the doctor’s work. Since the revolution Russia has been a mobilised society in which (as in war-time attributed to the perfusion technique. here) priorities at all levels have been laid down by the leaders. DISCUSSION Medicine had to be controlled in order that its practice should Doubts have been expressed about the safety of bubble fit the aims of the regime, and, so long as the chief aim was industrial production, doctors were under particular oxygenation,10 11 but in view of its successful clinical intensive in their certification of sickness. The resistance of pressure to retain decided this we while technique application doctors to State pressure was weakened by abolishing their simplifying the circuit. by indoctrination of students, and The substitution of gravity drainage for pump suction professional organisations, the doctor’s prestige and standard of living. reducing by immediately removed one of the main sources of anxiety Dr. Field notes a striking resemblance between the position of during bypass. While the venous pump was always care- doctors in Russia and that of schoolteachers in the U.S.A. fully balanced against the arterial, frequent variations in Admitting the advantages of central direction, he describes the the venous return necessitated continual adjustment of harm done by red tape, and by the setting of norms " in practhe venous pump. With gravity drainage and elimination tice, and he also describes the gross differences in the kind of of the venous pump the circulation adjusts itself auto- medical care given to different classes. Yet, after forty years’ vicissitudes the tradition of personal service has survived in matically and in a much shorter time. the Russian doctor; comparing him with his German colThe haemolysis caused by the sigmamotor pump, and a refugee said that, though he has no complex equipits limited output, prompted the trial of the Mono pump league,he is much warmer and more serious and, in the end, ment, which has a low haemolysis factor, is cheaper, and is much better for the patient". Though, as Dr. Field fully readily obtainable in this country. Its range of output is realises, the evidence of refugees from the U.S.S.R. will adequate for all prospective bypass cases and its constant- scarcely be unbiased, of 617 emigres questioned in New York, flow delivery is a superior means of returning blood to a 50% preferred Soviet medical arrangements and only 1800 the patient through a narrow cannula. A pulsatile flow results American. " In the Soviet Union ", said one," the doctor is the in peaks of high pressure in the tubing between pump and slave of the State.... In America he is the slave of the dollar." many ways a formidable indictment of the Soviet system, patient at the top of the input stroke, and at the same thisInbook is scrupulously fair. time the jet injected through the cannula into the femoral Advances in Virus Research rise to considerable turbulance. All these
heparin
was
given.
"
"
artery gives factors must be harmful to the blood and seem unnecessary when one considers that at the site of oxygen exchange in the capillaries the pulsatile flow has been lost.
Vol. 5. Editors: K. M. SMITH, virus research unit, Agricultural Research Council, Cambridge; M. A. LAUFFER, department of biophysics, University of Pittsburgh, Pennsylvania. New York: Academic Press. London: Academic Books. Pp. 376. 76s.
SUMMARY
A simplified circuit for a bubble oxygenator is described. Blood from the venæ cavae is conducted to the base of the’ oxygenator by gravity, so that a venous pump is unnecessary. For the arterial return aMono ’ pump is used. We would like to acknowledge the cooperation of Mono Pump* Ltd., who supplied a pump for protracted trial; of Allspeeds Ltd (Oakenshaw Works, Clayton-Le-Moors, Accrington, Lancs.), whc’ provided a Kopp variator; and of the department of medical illustra tion, Guy’s Hospital. The two patients were operated on by Si:r ’
.
-
10. 11.
Diesh, G., Flynn, P. J., Marable, S. A., Molder, D. G., Schmutzerr K. J., Longmire, W. P., Jr., Maloney, J. V. Surgery, 1957, 42, 67 Jordan, P., Jr., Tolstedt, G. E., Beretta, F. F. ibid. 1958, 43, 266.
THE fifth volume is very much up to the standard set by its predecessors, and continues to provide authoritative reviews on different aspects of virus research. The chapter by G. S. Stent on Mating in Reproduction of Bacterial Viruses is outstanding, and the synthesis of ideas presented in his review is likely to have a big influence on future research. There are three good reviews on virus groups-J. B. Brooksby wntes on foot-and-mouth disease, H. A. Wenner on the psittacosis group of viruses, and Ph. L’Heritier on the hereditary virus of drosophila. G. Bertani tackles an important topic—lysogeny— in a stimulating way. F. Fulton writes authoritativelv on complement fixation as applied to virology, and Anne Buzzell and M. Hanig wrestle with influenza-virus hxmagglutination.
Preliminary
Communication
A SINGLE-PUMP BUBBLE OXYGENATOR THE deliberate foaming of blood as a means of oxygenation was described by Schroederin 1882, but the principle was not applied to extracorporeal circulation until 1956. The description by De Wall et al.,2 of a disposable bubble oxygenator coupled with the fixedlow-flow principle, developed in their cross-circulation work, has been followed by a series of modifications of the apparatus. 3-6 We record here some further modifications which have evolved in the course of our experimental 7and clinical experiences and which have been dictated by the need for simplicity and economy.
With such aspiration, adherence of the caval walls to the orifices of the catheters often interfered with venous return. We have got over this difficulty by using gravity drainage into a venous reservoir-which has incidentally simplified adjustment of the pumps during bypass. We have found it possible to eliminate the venous pump and to rely on gravity to return the venous blood to the reservoir and thence to the oxygenator column. The whole apparatus is lowered so that the top of the oxygenator column is below the level of the right atrium (fig. 1). CARDIOPULMONARY
BYPASS
SURVIVAL EXPERIMENTS AND ONE
________________DRAINAGE
USING
GRAVITY
PUMP
APPARATUS
In the original circuit2 the venous blood was from the venæ eavx directly to aSigmamotor
aspirated ’ pump.
1. Schroeder, v. N. Arch. exp. Path. Pharmak. 1882, 15, 364. 2. De Wall, R. A., Warden, H. E., Gott, V. L., Ziegler, N. R., Varco, R. K., Lillehei, C. W. Surg. Clin. N. Amer. 1956, 36, 1025. 3. Gammelgard, R. A., Husfeldt, E., Therkelsen, F. Acta chir. scand. 1957, 112, 439. 4. Gott, V. L., De Wall, R. A., Paneth, M., Nazhi Zuhdi, M., Weirich, W., Varco, R., Lillehei, C. W. Thorax, 1957, 12, 1. 5. Cooley, D. A., Belmonte, B. A., Latson, J. R., Pierce, J. F. J. thorac. Surg. 1958, 35, 131. 6. Giannelli, S., Jr., Molthan, N. F., Best, R. J., Dull, J. A., Kirby, C. K. ibid. 1957, 34, 563. 7. Taylor, D. G. Guy’s Hosp. Rep. 1958, 107, 100. 8. Taylor, D. G. Cavanagh, J. B. Unpublished.
Elimination of the blood trauma.
venous
pump
removes a source
of
Under experimental conditions in our laboratory, a single T6S sigmamotor pump set at an output of 1 litre per minute, with a priming volume of 1 litre of dog blood, will produce 50-70 mg. of free hxmoglobin per 100 g. of blood after 1 hour. With a priming volume of 2 litres, and a flow of 2 litres per minute for 1 hour, it will produce 200-250 mg.
To reduce the blood damage we have substituted for the sigmamotor pump a commercially available BritishmadeMono’ pump, which utilises the archemedian The use of this pump has a sound screw principle. theoretical basis9 and it has given excellent results in our hands (see table).
gives a continuous flow of up to 6 litres per minute and maintain a constant output against a head of pressure of 90 feet of water. A standard production model B15 has been used, but sterile assembly of the unit has introduced some difficulties. The manufacturers are now developing a unit which can be easily autoclaved and assembled. At present the pump is driven by a ¼ h.p. single-phase 240-volt A.c. motor of 960 r.p.m. through a Kopp ’Variator’ to give a range of output from 700 to 5000 ml. per minute. The coronary-sinus return is collected in an evacuated reservoir of conventional type maintained at a negative pressure of 3 cm. of mercury by a separate suction pump. From the bottom of this reservoir the blood is pumped by a hand-operated roller pump to the venous reservoir. The circuit is primed by sucking filtered blood into the coronary-sinus reservoir and pumping it into the venous reservoir (fig. 2). The oxygenator column has an internal diameter of It
Fig. 1—Showing the relation between the pump oxygenator and the Patient.
Fig. 2-Showing coronary
sinus return to either the connecting tube reservoir and oxygenator or direct to venous reservoir (inset). The system can be primed through the venous The lead from coronary-sinus or coronary-sinus reservoirs. reservoir to external suction is not shown.
between
venous
can
9. Hall, J. E., James, P. A., Lucas, B. G. B., Waterson, D. J.
1958, 13, 1.
Thorax,
622
1½ in. has
an
and the tube connecting it to the internal diameter of 1/2 in.
venous
Russell Brock, whose continued support and encouragement have made this work possible.
reservoir
M. H. CASS *
RESULTS
This simplified circuit has been used on ten dogs and there have been seven survivors. In the first experiment a filter was not used but in the remainder one has been incorporated in the base of the helix. The amount of debris found on the filter at the end of each bypass has varied considerably, for no apparent reason. In the sixth experiment there was insufficient blood to prime the circuit and the operating level in the helix was around 200 ml. There should be at least 1 minute’s flow volume in the helix to reduce the possibility of micro-bubbles being drawn into the arterial line. The seventh dog died from a pulmonary embolus arising from the right atrial appendage. A clamp had been applied to the appendage and two purse-string sutures inserted 20 minutes before
Thoracic Surgical Unit, *
M.B. Sydney D. N. Ross M.B., B.SC. Cape Town, F.R.C.S. D. G. TAYLOR M.B. Belf., F.R.C.S.
Guy’s Hospital, London, S.E.1 During tenure of medical postgraduate training fellowship of the University of Sydney. Present address: Royal Children’s Hospital, Melbourne, Australia.
Reviews of Books Doctor and Patient in Soviet Russia MARK G. FIELD, PH.D., with a foreword by PAUL D. WHITE,
Cambridge, Mass.: Harvard University Press. London: Oxford University Press. 1958. Pp. 266. 40s.
M.D.
Dr. Field has spent only a month in Russia, but at the Russian Research Center at Harvard University he has made The apparatus used in clinical cases has now been a long study of Soviet books and journals, has interviewed modified similarly. Two patients (a tetralogy of Fallot many doctors who have left Russia, and has analysed answers and a ventricular septal defect) have been operated on to a questionary addressed to 1650 former Soviet citizens. His using the modified oxygenator circuit and a single sigma- book is described as a study not of Soviet medicine but in the motor pump. The patient in whom the ventricular septal sociology of the medical profession; but as such it is the most defect was closed is alive and well. The patient with penetrating commentary on medical Russia that we have seen. tetralogy of Fallot died 24 hours after attempted complete Soviet medicine provides, he says, almost the extreme example correction. Consciousness was regained and death is not of interference with the doctor’s work. Since the revolution Russia has been a mobilised society in which (as in war-time attributed to the perfusion technique. here) priorities at all levels have been laid down by the leaders. DISCUSSION Medicine had to be controlled in order that its practice should Doubts have been expressed about the safety of bubble fit the aims of the regime, and, so long as the chief aim was industrial production, doctors were under particular oxygenation,10 11 but in view of its successful clinical intensive in their certification of sickness. The resistance of pressure to retain decided this we while technique application doctors to State pressure was weakened by abolishing their simplifying the circuit. by indoctrination of students, and The substitution of gravity drainage for pump suction professional organisations, the doctor’s prestige and standard of living. reducing by immediately removed one of the main sources of anxiety Dr. Field notes a striking resemblance between the position of during bypass. While the venous pump was always care- doctors in Russia and that of schoolteachers in the U.S.A. fully balanced against the arterial, frequent variations in Admitting the advantages of central direction, he describes the the venous return necessitated continual adjustment of harm done by red tape, and by the setting of norms " in practhe venous pump. With gravity drainage and elimination tice, and he also describes the gross differences in the kind of of the venous pump the circulation adjusts itself auto- medical care given to different classes. Yet, after forty years’ vicissitudes the tradition of personal service has survived in matically and in a much shorter time. the Russian doctor; comparing him with his German colThe haemolysis caused by the sigmamotor pump, and a refugee said that, though he has no complex equipits limited output, prompted the trial of the Mono pump league,he is much warmer and more serious and, in the end, ment, which has a low haemolysis factor, is cheaper, and is much better for the patient". Though, as Dr. Field fully readily obtainable in this country. Its range of output is realises, the evidence of refugees from the U.S.S.R. will adequate for all prospective bypass cases and its constant- scarcely be unbiased, of 617 emigres questioned in New York, flow delivery is a superior means of returning blood to a 50% preferred Soviet medical arrangements and only 1800 the patient through a narrow cannula. A pulsatile flow results American. " In the Soviet Union ", said one," the doctor is the in peaks of high pressure in the tubing between pump and slave of the State.... In America he is the slave of the dollar." many ways a formidable indictment of the Soviet system, patient at the top of the input stroke, and at the same thisInbook is scrupulously fair. time the jet injected through the cannula into the femoral Advances in Virus Research rise to considerable turbulance. All these
heparin
was
given.
"
"
artery gives factors must be harmful to the blood and seem unnecessary when one considers that at the site of oxygen exchange in the capillaries the pulsatile flow has been lost.
Vol. 5. Editors: K. M. SMITH, virus research unit, Agricultural Research Council, Cambridge; M. A. LAUFFER, department of biophysics, University of Pittsburgh, Pennsylvania. New York: Academic Press. London: Academic Books. Pp. 376. 76s.
SUMMARY
A simplified circuit for a bubble oxygenator is described. Blood from the venæ cavae is conducted to the base of the’ oxygenator by gravity, so that a venous pump is unnecessary. For the arterial return aMono ’ pump is used. We would like to acknowledge the cooperation of Mono Pump* Ltd., who supplied a pump for protracted trial; of Allspeeds Ltd (Oakenshaw Works, Clayton-Le-Moors, Accrington, Lancs.), whc’ provided a Kopp variator; and of the department of medical illustra tion, Guy’s Hospital. The two patients were operated on by Si:r ’
.
-
10. 11.
Diesh, G., Flynn, P. J., Marable, S. A., Molder, D. G., Schmutzerr K. J., Longmire, W. P., Jr., Maloney, J. V. Surgery, 1957, 42, 67 Jordan, P., Jr., Tolstedt, G. E., Beretta, F. F. ibid. 1958, 43, 266.
THE fifth volume is very much up to the standard set by its predecessors, and continues to provide authoritative reviews on different aspects of virus research. The chapter by G. S. Stent on Mating in Reproduction of Bacterial Viruses is outstanding, and the synthesis of ideas presented in his review is likely to have a big influence on future research. There are three good reviews on virus groups-J. B. Brooksby wntes on foot-and-mouth disease, H. A. Wenner on the psittacosis group of viruses, and Ph. L’Heritier on the hereditary virus of drosophila. G. Bertani tackles an important topic—lysogeny— in a stimulating way. F. Fulton writes authoritativelv on complement fixation as applied to virology, and Anne Buzzell and M. Hanig wrestle with influenza-virus hxmagglutination.