Monday Morning, April 25, 1955
8:30 A.M. Scientific
Session: THORACIC SURGICAL FORUM.
13. Anastomosis of Right
Auricle to Pulmonary Artery in the Treatment of Tricuspid Atresia.
Elliott S.
Hurwitt, Dennison Young (by
invitation) and
Doris J.
W. Escher (by invitation), New
York, N. Y.
On November 15, 1954, in the Forum on Fundamental
Surgical Problems of the American College of Surgeons, a new approach to the
correction of tricuspid atresia was described by Warden, DeWall, and Varco. By
anastomosing the tip of the right auricular appendage to the main pulmonary
artery in dogs with suture-obliteration of the tricuspid valve, they utilized
the pumping potential of the right auricle to convey the systemic venous blood
to the pulmonary circulation. An infant desperately ill with an atresia of the
pulmonary conus and a common ventricle (cor triloculare) as components of
complicated congenital heart disease was subjected to this new operation under
hypothermia on December 8, 1954. Although the outcome of this initial attempt
was unsuccessful, an analysis of the anatomical and physiological data obtained
during operation emphasizes the crucial importance of thorough study in
evaluating the rationale of this procedure. The pressure gradient and
comparative degree of oxygen saturation of the blood in the right auricle and
pulmonary artery are the critical readings. On the basis of a study of these
data, the technical aspects of the operation, and the autopsy findings,
recommendations are made concerning the use of this operation in the surgical
management of tri-cuspid atresia.
14. Autogenous Thoracic Aorta Grafts of Pericardium and Nylon Net Using
a Thrombin-Fibrinogen Coaglum.
Richard H.
Adler (by invitation), Denver,
Colo.
In an effort to eliminate certain undesirable features
associated with aortic homografts and the maintenance of an aortic vessel bank,
a method has been developed for making thoracic aortografts from autogenous
pericardium, nylon net and a thrombin-fibrinogen coagulum at the time of
thoracotomy. First, a simple, practical procedure was evolved for quickly
preparing a sticky coagulum from thrombin and fibrinogen. Thereafter, sterile
grafts could be made at the operating table by the following method. A sheet of
pericardium is removed and trimmed free of excess fat. A rectangular piece of
nylon net, fashioned to desired size, is then stuck to the external surface of
the pericardium by means of freshly interposed thrombin-fibrinogen coagulum.
Within several minutes the coagulum has set and the two layers become adherent;
the pericardium serves as an intima and the nylon net as an external elastic
support. This tissue is then placed around a cylinder and sutured into a tube
of appropriate length and diameter while the thoracic aorta is being prepared for
resection.
Such grafts, varying in length from 2.5 to 7.0 cm.,
have been used to replace excised segments of thoracic aorta in approximately
thirty dogs. To avoid occasional spinal cord damage and heart failure during
the period of aortic occlusion required for anastomosis, a siliconized
polythene tube shunt was used to bridge the arch and descending aorta. The
grafts have been studied at varying postoperative periods grossly,
histologically, and by direct transventricular aortography. Most grafts so studied
appear to function satisfactorily.
15. The Lymphatic Drainage of Silver-Coated Radioactive Gold Colloids
Following Intra-Thoracic Administration to Pneumonec-tomized Dogs.
P. F. Hahn (by
invitation), Robert A. Matuska (by invitation),
Robert I. Carlson, Stewart H. Auerbach (by invitation) and
George R. Meneely (by invitation), Nashville,
Tenn.
At various intervals following left pneumonectomy,
therapeutic quantities of silver-coated radioactive colloid material were
injected into the empty hemithorax. There were no deaths in the animals
injected with the radioactive substance. The animals were sacrificed in two to
five days and the radioactive content of the antero-superior mediastinal, right
superior mediastinal, left superior mediastinal, and bronchial and carinal
nodes was determined. In general, good radiation was obtained in all of the
superior mediastinal nodes. The radioactive content of the bronchial and
carinal nodes was unpredictable.
Several animals were allowed to live several weeks
after injection and histological examination showed nearly complete destruction
of the irradiated mediastinal nodes. Histological examination of the liver and
spleen in these animals showed no architectural abnormalities. Studies of the
parietal pleura and of the pericardium showed no histological changes.
Bronchial stump healing was unimpaired. Liver, spleen, and striated muscle were
studied for radioactivity; and histologically radiation to the liver and spleen
was well within tolerated limits.
Implications
for use of such colloids as adjuvants to surgery in bronchogenic malignancy
will be discussed. The advantages over the intrabronchial route previously
reported rest in simplicity of administration and the ability to administer the
drug repeatedly if necessary.
16. Circumferential Suture of the Mitral Ring -A Possible Method for
the Surgical Correction of Mitral Insufficiency.
Julio C. Davila, Robert G. Trout, Bart S. Iaia and Frank Mansure
(all by invitation). Sponsored by Robert P. Glover, Philadelphia, Pa.
The purpose of this communication is to present the
experience gained in the experimental laboratory in the development of a
technique for circumferential suturing of the mitral valve.
A brief comment is made regarding the rationale of this
approach to the treatment of mitral insufficiency.
Over one hundred dogs have been used to study various
aspects of the problem. A description of the technique which has been developed
is given. The early effects of this procedure, using several different suture
materials, in the hearts of normal dogs, are discussed. The effectiveness of
the method in correcting artificially produced mitral regurgitation is
presented.
Conclusions are based upon electrocardiographic,
hemodynamic and anatomo-pathologic observations.
17. Studies
Upon the Physiological Function of the Human Vagus Nerve in Various
Pathological Pulmonary States.
Osler A. Abbott, W. E. Van Fleit (by invitation), E. R. Duschesne (by invitation)
and A. E. Roberto (by
invitation), Emory University, Ga.
An analysis is presented of data obtained upon the
effect of paralysis of the vagus nerve upon the pulmonary artery pressure in
numerous different types of bronchopulmonary disease. Defunctionalization of
the vagus nerve has been obtained by these methods: namely (a) the effect of
large doses of intravenous probanthine upon preoperative cardiac catheter
studies, (b) the effect of novocaine block of the isolated left or right vagus
nerve upon pulmonary artery blood pressure during thoracotomy, and (c) cardiac
catheterization studies in patients who have undergone unilateral or bilateral
high vagus nerve transection. Comparative effects of novocaine block of the
dorsal sympathetic chain are also reported. The studies obtained at the
operating table were performed under standard conditions of anesthesia with
mechanically regulated and recorded ventilatory pressure. The effect of
different levels of ventilatory pressure upon the pulmonary artery pressure
with and without vagus nerve control are reported. The variation in response
obtained in different pathological states suggests the degree of vagotonia
involved in various conditions. An attempt is made to parallel the pulmonary
artery pressure response to the variation in tidal air and oxygen consumption
values produced by the loss of vagus nerve control of the pulmonary bed.
18. Temporary Unilateral Occlusion of the Pulmonary Artery in the
Preoperative Evaluation of Thoracic Patients. A Preliminary Report.
Herbert Sloan and Joe D. Morris (by invitation), Ann
Arbor, Mich.
Prediction of the effect of pulmonary resection,
particularly pneumonectomy, on the cardiovascular system of patients is not
possible in the same objective manner in which the effect on pulmonary function
can be assessed. An attempt has been made to produce changes in the pulmonary
circulation before operation which would simulate those resulting from
pneumonectomy.
The pulmonary artery on the side of the proposed
resection has been catheterized and the artery occluded completely with a
balloon. Changes in pulmonary artery pressure, cardiac output, systemic
arterial oxygen saturation and respiratory exchange have been recorded. The
experiment has been repeated with the balloon inflated during a period of
exercise.
Information has been obtained which may allow the
determination before operation of the possible later development of pulmonary
hypertension and cor pul-monale. Observations of the ability of patients to
increase cardiac output sufficiently to withstand a thoracic operation and to
maintain normal arterial oxygen saturations with one pulmonary artery occluded
have been carried out. These studies have been correlated with similar studies
made during operation.
19. Coronary Perfusion for Longer Periods of Cardiac Occlusion Under
Hypothermia.
Norman E. Shumway (by invitation) and Marvin L. Gliedman
(by invitation)
Sponsored by F. john lewis, Minneapolis,
Minn.
A limiting factor in the use of general hypothermia for
intracardiac surgery is the relatively short time available for cardiac
occlusion. The purpose of our experiments has been to extend this period by
means of coronary perfusion. Fifteen minutes has been the maximum duration of
cardiac occlusion tolerated by dogs at 25° C. Through the agency of coronary
perfusion this time interval was prolonged up to thirty minutes.
After an initial series of experiments confirmed the
observation that citrated blood produced ventricular fibrillation, heparinated
blood was used for the perfusions. The ascending aorta was cannulated via the
subclavian or brachiocephalic artery. Before the perfusion was begun, the aorta
was obstructed by an inflatable cuff on the catheter tip. Non-crushing clamps
applied distal to the catheter gave additional security that all perfusate
would flow into the coronary arteries. The blood was taken from a reservoir,
passed through a simple bubble type oxygenator, and then pumped through the
coronary vessels at a rate of approximately 2 cc. per Ib. of body weight per
minute. Blood entering the heart through the coronary sinus was allowed to
leave the system through a right atriotomy or ventriculotomy.
The time permitted by hypothermia for intracardiac
surgery has been a function of the resuscitative power of the heart. With
cardiac perfusion resistance of the nervous system to anoxia becomes the
determining factor. In the dog with coronary perfusion 30 minutes of cardiac
occlusion at 25° C. has been tolerated without evident neurological deficit.
20. Blood Volume Studies in Thoracic Surgical Procedures Using
Radioactive lodinated Human Serum Albumin (RIHSA).
Clifford F.
Storey, Charles G. Foster (by invitation) and
Thomas G. Mitchell (by invitation), St.
Albans, N. Y.
Despite the fact that thoracic surgical procedures are
commonly performed today, there are only a few reports in the literature
concerning the blood volume changes which occur in patients undergoing chest
surgery.
Since the replacement of blood during and following
surgery is based upon the estimated blood loss, the surgeon needs a practical
and accurate means of measuring blood loss. The authors feel that blood volume
determinations with RIHSA pre and postoperatively meet this need.
The blood volume changes observed in patients subjected
to major thoracic surgical procedures as measured by RIHSA are presented. A
comparison of blood loss during surgery as measured by the dry weighed sponge
technique and RIHSA is also made.
21. Induced
Cardiac Arrest for Intracardiac Surgical Procedures.
Conrad R. Lam, Thomas Geoghegan (by
invitation) and Alfred Lepore
(by invitation), Detroit, Mich.
There would be a great advantage in the performance of
intracardiac operations if the organ were brought temporarily to standstill.
The ideal of a dry heart would be nearly or perfectly attained, since there
would be no coronary sinus flow. Furthermore, we have demonstrated that
complete cardiac resuscitation is more easily attained if the heart is stopped
during caval occlusion rather than being allowed to beat with an inadequate
blood supply.
With the dog's brain protected by hypothermia, we have
occluded the two cavas and azygos vein, and have stopped the heart with the
intraventricular injection of potassium chloride. Various complicated
intracardiac procedures have been carried out with facility under these
conditions. The heart is easily resuscitated from the condition of standstill
by massage and defibrillation.
22. Open Left Heart Surgery in Dogs During Cardiac Arrest Below 10° C.
Temperature with and without Extracorporeal Circulation.
Frank Gollan, Reginald Phillips, Jr., James T. Grace and
Raymond M.
Jones (all by invitation), Nashville,
Tenn.
The body temperature of dogs can be lowered to the
freezing point of water within one hour if the venous return is circulated,
oxygenated and refrigerated in a small, plastic pump-oxygenator. At 13° C. the
heart goes into asystole and the left heart can be opened for prolonged
intracardiac surgery. Ventricular fibrillation, coronary flow or air embolism
do not interfere with this procedure. On rewarming the blood in the
extracorporeal circulation the heart resumes its regular beat and at 30° C. the
pump-oxygenator can be turned off.
In a similar way rapid hypothermic asystole without
ventricular fibrillation can be achieved by combining immersion in ice water
with cooling of the pulmonary circulation by hyperventilation with refrigerated
oxygen. After closure of the left cardiotomy, inhalation of warm oxygen,
cardiac massage, clamping of the thoracic aorta and rapid body rewarming
restore normal heart activity. Cooling of the extra-corporeal or of the
pulmonary circulation provides a bloodless field during cardiac arrest. While
the former procedure lends itself advantageously for complex and prolonged
intracardiac surgery the latter is applicable to simpler and shorter
operations.
23. Physiological Observations
in Experimental Pulmonary Insufficiency.
Robert G. Ellison, Walter J. Brown, Jr. (by invitation),
Elmer E. Hague, Jr. (by invitation) and William F. Hamilton
(by invitation), Augusta, Ga.
The surgical attack upon congenital stenosis of the
pulmonary valve has been quite successful in relieving symptoms due to this
disease. Right ventricular pressures frequently fail to return to normal after
the Brock technique and for this reason there has been an enthusiasm on the
part of some surgeons to attack the valve under direct vision and in some cases
to excise portion sof it. This necessarily creates insufficiency of the valve.
Swan minimizes the dangers of pulmonary insufficiency and feels that it may be
desirable to accept some degree of insufficiency in order to relieve stenosis
completely. On the other hand, some observers have felt that pulmonary
insufficiency is tolerated poorly. This report deals with the presentation of
physiological data gathered on a small group of dogs in whom the pulmonary
valves had been completely excised.
The first five dogs were operated upon under
hypothermia, but the others under normothermic conditions. Eight dogs have been
followed for from one to 14 months. The data obtained indicates that complete
pulmonary valvulectomy has not yet produced any noticeable physiological
handicap. As a result of an increase in stroke volume, the right ventricular
systolic pressure was elevated, but in no case was the right ventricular
end-diastolic pressure significantly above normal. Pulmonary diastolic pressure
was uniformly low. Physiological data will be presented in detail.
24. Experimental
Transposition of the Great Vessels.
Sanford E.
Leeds, Morris M. Culliner (by invitation) and
Sherman H.
Strauss (by invitation), San
Francisco, Calif.
Complete transposition of the great vessels is a common
congenital malformation for which there is no satisfactory treatment. It cannot
be created in laboratory animals for experimental study at the present time.
Two types of operative procedures were performed in dogs, usually in stages, in
order partially to transpose the normal circulation. Type I consisted of
connecting the distal right superior pulmonary artery to the right atrium,
creating an interatrial septal defect, and end-to-end anastomosis between the
brachiocephalic and right pulmonary arteries. Excision of a part of the left
lung was included in most of these animals. The Type II preparation, with and
without an interatrial septal defect, included connection of the right superior
pulmonary vein to the right atrium and the superior vena cava to the left
atrium. By these means, an attempt was made to produce cyanosis and a
balanced circulation, thus testing the efficiency of transposing pulmonary and
systemic veins to correct cyanosis in patients with complete
transposition of the great vessels.
Seventy-four operations were performed in forty-two
dogs. Of the surviving animals, which became cyanotic, some were studied for
more than two years. Observations were made on the flow through the interatrial
septal defect during temporary occlusion of the left pulmonary artery, the
right pulmonary artery having been divided for anastomosis with a systemic
artery.
The application of these experiments to the clinical
problem of complete transposition of the great vessels will be discussed.
25. Controlled
Total Body Arterial Perfusion for Open Intracardiac Surgery.
Herbert E.
Warden (by invitation), Richard A. DeWall (by invitation),
J. Bradley Aust (by
invitation), Newell Ziegler (by
invitation),
Raymond C.
Read (by invitation), Richard L. Varco and
C. Walton Lillehei, Minneapolis,
Minn.
Over the past several months controlled cross
circulation has been used successfully at the University of Minnesota Hospitals
as a means of performing open intracardiac surgery for prolonged periods of
time. It is felt that an obvious improvement in the technique would be the
elimination of the living donor from the operative set-up. Variation in the
procedure that accomplishes this end has been developed and will be presented.
A simple method of oxygenation of blood without damage
and without the need for special equipment has been utilized to replace the
donor in the cross circulation circuit. By use of this method in conjunction
with the concept of reduced flow and the mechanical principles of controlled
cross circulation (which insure a quantitative balance between the arterial
perfusion to and the venous withdrawal from the recipient) it is now possible
to occlude the cardiac inflow and provide ample opportunity to operate within
the chambers of a dry heart.
Several animals have been subjected to and have
survived prolonged periods of cardiac by-pass using this technique. In
addition, a physiologic evaluation of the method has been carried out in some
detail with particular attention being paid to changes in the normal acid base
relationships as indicated by pre and post perfusion pH, O2, and CO2
determinations. Similarly changes in hemoglobin, hematocrit, platelet counts,
and red cell fragility have been determined and will be presented.
26. The Arterialization
of Blood as It Applies to the Mechanical Heart-Lung Apparatus.
F. D. Dodrill and Alfred Lui (by invitation), Detroit,
Mich.
The mechanical heart reported by one of us has been
previously described. We are describing the addition of an oxygenator used in
combination with the mechanical heart. A porous plate is used, on the under
side of which oxygen is present under slight pressure, while on the top side
the venous blood is delivered. Oxygen is absorbed by the venous blood as it
rises in the chamber. The plate is so constructed that the tiny holes are not
more than 10 microns in diameter. Any size plate can be made to accommodate any
quantity of venous blood. Excess oxygen is allowed to escape in large bubbles.
The excess oxygen in the form of bubbles is passed through an absorption
chamber in which the large bubbles coalesce and break due to the change in
surface tension. This change in surface tension is brought about by the
presence of a small amount of an organo-polysiloxane. The free oxygen as well
as the carbon dioxide is allowed to pass into the atmosphere.
Using such an apparatus, the venous blood is oxygenated
to 100 per cent saturation and the carbon dioxide is removed in amounts which
keep the carbon dioxide content of the arterial blood essentially normal.
Studies of the pH also indicate figures within a normal range. Such an
apparatus is connected between the two sides of the mechanical heart which are,
in effect, two ventricles. The right side of the pump delivers blood through
the oxygenator while the left side delivers it into the arterial system. Using
this apparatus, we have been able to maintain the open heart in dogs for over
30 minutes with chemical and physiological standards approaching normal.
27. The Alveolar Carbon
Dioxide Tension During Intrathoracic Operations.
Thomas F. Nealon (by invitation), George J. Haupt (by invitation)
and John H. Gibbon, Jr., Philadelphia, Pa.
A recent report from this laboratory demonstrated that
adequate pulmonary ventilation can be achieved by intermittent positive and
negative pressure during prolonged intrathoracic operations. The present report
is a comparison between manual intermittent positive pressure and mechanical
positive and negative pressure pulmonary ventilation. These techniques were
alternated during operation and the following studies carried out. Total
ventilation was measured by a dry test volume displacement gas meter. The per
cent of carbon dioxide in the endexpiratory gas (alveolar air) was continuously
measured and recorded with a Liston-Becker infrared gas analyzer. Intermittent
arterial blood samples were analyzed for pH, CO2 content, O2
content, O2 capacity, and sodium and potassium concentrations. The
pCO2 and O2 saturation of arterial blood were calculated
from these determinations. The pCO2 of the arterial blood was
correlated with the alveolar carbon dioxide tension determined by the infra-red
gas analyzer. In addition, the sodium and potassium concentrations of the
arterial blood are compared with the pCO2 and pH.
The results of this study indicated that adequate
pulmonary ventilation, evidenced by a normal or low alveolar pCO2
and normal arterial oxygen saturation, can be achieved by either technique in
patients with unimpaired pulmonary function. In patients with decreased
pulmonary function, especially those with severe degrees of emphysema,
intermittent positive and negative pressure provided adequate ventilation. On
the other hand, intermittent positive pressure did not provide adequate
ventilation in such patients or could not be employed because of its
deleterious effect on the circulation, i.e., diminished cardiac output with
resultant hypotension.
