Effect of cardiopulmonary bypass on cefazolin disposition.

Cefazolin kinetics was studied in 8 patients the day before (PREOP), during (SURG), and the day after (POSTOP) cardiopulmonary bypass (CPB) surgery. PREOP (48.6 ml/min) and POSTOP (46.6 ml/min) total body clearances were of the same order and both were greater than the SURG (27.4 ml/min) total body clearance. Since cefazolin is almost entirely eliminated by the kidney, the lower SURG clearance is a result of reduced renal elimination, as confirmed by measuring cefazolin SURG (28.7 ml/min) and POSTOP (52.9 ml/min) renal clearance. The reduction in cefazolin renal elimination was the same throughout the surgical procedure, including the period of extracorporeal circulation. Cefazolin distribution was altered by the operative procedure as evidence by a higher SURG steady-state volume of distribution. This increase in apparent cefazolin distribution volume brought about by surgery was not seen with cephalothin, which was investigated by us in a similar group of patients. The different effect of CPB surgery on cefazolin and cephalothin distribution may be due to differences in plasma protein binding.

Cephalothin kinetics: before, during, and after cardiopulmonary bypass surgery.

Cephalothin kinetics was studied in 5 patients the day before (PREOP), during (SURG), and the day after (POSTOP) cardiopulmonary bypass surgery. The PREOP (114 ml/min) and SURG (94 ml/min) renal clearances were of the same order but both were less than POSTOP renal clearance (248 ml/min). Cephalothin total body clearance during operation was lower (p less than 0.01) than PREOP or POSTOP clearance, with decreased metabolic clearance the primary cause. There was reduction in cephalothin elimination throughout the surgical procedure, not only in the period of extracorporeal circulation, indicating that general anesthesia had a significant influence on drug disposition. The metabolite deacetylcephalothin was rapidly formed on all 3 days and its kinetic behavior paralleled that of the parent drug.

Antibiotic prophylaxis for open-heart surgery.

A randomized, prospective study of the relative effectiveness of broad-spectrum versus specific antistaphylococal antibiotic prophylaxis in patients having open-heart surgery was performed between May, 1972, and June, 1973. All patients undergoing open-heart surgery was assigned randomly (by hospital number) to receive either methicillin or cephalothin beginning the night before operation. There were 132 patients in the cephalothin group and 129 in the methicillin group. There was no statistically significant differences in age or duration of hospitalization, cardiopulmonary bypass, urinary tract drainage, or postoperative fever. There was a significant difference in the ratio of male to total patients (cephalothin group, 0.67; methicillin group, 0.52; p less than 0.02) and duration of operation (cephalothin group, 4.27 hours; methicillin group, 3.87 hours; p less than 0.05). The methicillin group had a statistically significant higher rate of urinary tract infection (cephalothin group, 3 cases; emthicillin group, 22 cases, p less than 0.05), pneumonia (cephalothin group, no cases; methicillin group, 9 cases; p less than 0.01), and episodes of sepsis and prosthetic valve endocarditis (cephalothin group, no cases; methicillin group, 11 cases, p less than 0.001). The incidence of wound infections and positive blood cultures from blood obtained immediately after termination of cardiopulmonary bypass was not significantly different between the two groups. Cephalothin has replaced methicillin as the routine prophylaxis for open-heart surgery at our institution.

Chylothorax after median sternotomy for intrapericardial cardiac surgery.

Chylothorax following cardiovascular surgery occurs with an incidence of 0.25 to 0.5 per cent. We are aware of only 5 reported cases in the literature following intrapericardial procedures. This report includes the forth documented case following ventricular septal defect closure and the first 4 reported cases following median sternotomy for intrapericardial acquired cardiac disease. The fistula in all cases occurred in the anterior mediastinum in the region of the thymic tissue. This problem can be prevented by surgical ligation of the thymic vascular structures at the time of dissection rather than the use of electrocautery. The treatment recommended is a 2 week trial of conservative therapy with a diet of medium-chain triglycerides and closed-chest suction. If this fails, surgical division of the fistula is recommended.

Effect on myocardial perfusion of simultaneous delivery of cardioplegic solution through a single coronary artery and the coronary sinus.

OBJECTIVE: This study was to determine whether simultaneous antegrade-retrograde cardioplegia through a single coronary artery and the coronary sinus provides sufficient and homogeneous perfusion to the heart. METHODS: Simultaneous antegrade-retrograde cardioplegia was conducted in 7 isolated pig hearts through the coronary sinus in conjunction with the left anterior descending artery, the left circumflex artery, and the right coronary artery, respectively. The efficacy of simultaneous antegrade-retrograde cardioplegia for myocardial perfusion was assessed by monitoring the distribution of magnetic resonance contrast agent and measuring the effluent from the venting coronary arteries. RESULTS: Injection of contrast agent into a perfusing artery during simultaneous antegrade-retrograde cardioplegia resulted in increased image signal intensity not only in the territory of the perfusing artery but also in the areas normally served by the other 2 venting arteries (including the right ventricular wall). The myocardium in the territories of the 2 venting arteries was lightened with contrast agent given into the coronary sinus during simultaneous antegrade-retrograde cardioplegia. Myocardium in the perfusing artery territory and right ventricular wall remained dark. Moreover, a significant amount of effluent was collected from the venting arteries during simultaneous antegrade-retrograde cardioplegia: 4.7 to 7.8 mL/min from the right coronary artery; 10.5 to 17.7 mL/min from the left anterior descending artery; and 9.7 to 15.2 mL/min from the left circumflex coronary artery. CONCLUSIONS: Simultaneous antegrade-retrograde cardioplegia through a single coronary artery and the coronary sinus provides homogeneous perfusion to the entire heart. During simultaneous antegrade-retrograde cardioplegia, arterial flow supports its own designated myocardium, as well as adjacent myocardium normally served by the venting arteries; the arterial route also supports the right ventricular free wall when the right coronary artery is vented. Venous perfusion of simultaneous antegrade-retrograde cardioplegia mainly supports myocardium in the territories of the venting arteries and does not perfuse the right ventricular free wall. Blood flow delivered to myocardium normally supported by the venting arteries is believed to be sufficient to prevent ischemic injury.

CPK-MB isoenzyme: use in diagnosis of acute myocardial infarction in the early postoperative period.

The diagnosis of acute myocardial infarction (AMI) in the early postoperative period may be quite difficult in certain patients. Electrocardiograms fail to be diagnostic of AMI in as many as one third of patients with myocardial injury found at autopsy. Enzyme patterns commonly used to diagnose AMI in patients admitted to coronary care units are obscured by muscle injury, medications, cardioversion, surgical manipulation, and blood transfusion. The MB isoenzyme of creatinine phosphokinase (CPK) has been described as a specific indicator of myocardial injury. Therefore the CPK-MB isoenzyme level was evaluated as a potential aid in the diagnosis of AMI in the early postoperative period. Thirty patients undergoing cardiac surgery and 7 patients undergoing thoracic surgery not involving the heart were studied. CPK-MB isoenzyme was present in the serum in 10 of 30 patients after cardiac surgery but in none of 7 patients after thoracic surgery. The presence of CPK-MB isoenzyme was found to be a valuable adjunctive indicator in the diagnosis of AMI in the early postoperative period.

Composite replacement of the aortic valve and ascending aorta.

This report comprises 16 consecutive patients with ascending aortic aneurysms caused by cystic medical necrosis. We replaced the ascending aorta and aortic valve with a tightly woven Dacron graft containing a Lillehei-Kaster valve prosthesis and implanted the coronary ostia in the sides of the graft. All but two patients had massive aortic insufficiency. Postoperative catheterization was performed in 13 patients, and all surviving patients have been seen within the past 6 months. There was one perioperative death (6 percent) and two late deaths. Eleven survivors are in Class I and two are in Class II (N.Y.H.A.). Angiographically demonstrated late complications have included psuedoaneurysms of the coronary ostium (two), paravalvular leak (one), and pseudoaneurysm of the distal suture line (one). Two of these four patients were asymptomatic. Two of the four patients have had successful repair of these defects and a third is awaiting operation. Compositive replacement carries a low operative risk and minimizes problems of intraoperative bleeding. In view of the incidence of late suture line problems, routine angiography 6 to 12 months postoperatively is recommended. If new symptoms occur or if there is a change in the cardiac silhousette on chest roentgenogram, the patient should be recatheterized.

Ten-year follow-up study of patients who had double valve replacement with the St. Jude Medical prosthesis.

Records of 100 consecutive patients who had received double valve replacement were reviewed (41 men, 59 women, mean age, 60.86 +/- 13.0 years). The early death rate was 6% (six patients). A completed follow-up rate of 93% was accomplished in these 94 patients who left the hospital (mean, 309.8 patient-years). Twenty-three of these patients died. The late death rate was 26.4%. Four patients experienced thromboembolic episodes (one transient and three permanent; all were minor). One patient had a paravalvular leak (mitral), and another had thrombosis of the tricuspid valve. There was no clinical evidence of hemolysis, infective endocarditis, or structural failure or anticoagulant-related bleeding. One of those 23 patients who died was the patient who had thrombosis of the tricuspid valve. Another three patients died of sudden and unknown causes, 15 of cardiac-related problems and four of noncardiac problems. Of those patients who survived, New York Heart Association functional class improved significantly (from 66% class III before to 85% class I after). Linearized rates for thromboembolism and thrombosis were 1.29 +/- 0.65 and 0.32 +/- 0.32 per 100 patient-years, respectively. The actuarial estimates of incidence free of all complications and valve-related deaths were 77.9% +/- 10.6%. Despite the advanced heart disease involving two native valves, the patients who had double valve replacement with the St. Jude Medical prosthesis had very good results over a 10-year period.

The effects of retrograde cardioplegia technique on myocardial perfusion and energy metabolism: a magnetic resonance imaging and localized phosphorus 31 spectroscopy study in isolated pig hearts.

OBJECTIVE: The present work was designed to study the myocardial perfusion and energy metabolism during retrograde cardioplegia performed with different methods, including deep coronary sinus cardioplegia, coronary sinus orifice cardioplegia, and right atrial cardioplegia. METHODS: Isolated pig hearts were subjected to antegrade cardioplegia, right atrial cardioplegia, deep coronary sinus cardioplegia, and coronary sinus orifice cardioplegia in a random order. Cardioplegic distribution was assessed by T1-weighted magnetic resonance imaging in 1 group of hearts (n = 8). The flow dynamics of cardioplegia were assessed by T2*-weighted imaging in a second group of hearts (n = 8). RESULTS: T1-weighted images revealed an apparent perfusion defect in the posterior wall of the left ventricle, the posterior portion of the interventricular septum, and the right ventricular free wall during deep coronary sinus cardioplegia. The perfusion defect observed in the first 2 regions with deep coronary sinus cardioplegia resolved with coronary sinus orifice cardioplegia. Right atrial cardioplegia provided the most homogeneous perfusion to all regions of the myocardium relative to the other 2 retrograde cardioplegia modalities. T2*-weighted images showed that the 3 retrograde cardioplegia modalities provided similar cardioplegic flow velocities. Localized phosphorus 31 spectroscopy showed that the levels of adenosine triphosphate and phosphocreatine were significantly lower in the posterior wall (adenosine triphosphate, 42.86% +/- 5.91% of its initial value; phosphocreatine, 11.43% +/- 11.3%) than the anterior wall (adenosine triphosphate, 89.19% +/- 8.83%; phosphocreatine, 59.54% +/- 12.58%) of the left ventricle during 70 minutes of normothermic deep coronary sinus cardioplegia. CONCLUSIONS: Deep coronary sinus cardioplegia results in myocardial ischemia in the posterior wall of the left ventricle and the posterior portion of the interventricular septum, as well as in the right ventricular free wall. Coronary sinus orifice cardioplegia improves cardioplegic distribution in these regions. Relative to deep coronary sinus cardioplegia and coronary sinus orifice cardioplegia, right atrial cardioplegia provides the most homogeneous perfusion.

Effects of retrograde cardioplegia on myocardial perfusion and energy metabolism in immature porcine myocardium.

OBJECTIVES: Retrograde cardioplegia has been widely used for the protection of adult hearts during cardiac operations. Its efficacy to protect immature myocardium is still unclear. This study was designed to assess the effects of retrograde cardioplegia on myocardial perfusion and energy metabolism in immature hearts. METHODS: Piglet hearts were divided into 3 groups. Hearts in group 1 were used to assess myocardial perfusion of retrograde cardioplegia by means of magnetic resonance imaging. Hearts in groups 2 and 3 were used to assess the effects of retrograde cardioplegia on myocardial energy metabolism by use of phosphorus 31 magnetic resonance spectroscopy. RESULTS: Magnetic resonance images showed that perfusion with retrograde cardioplegic solution was heterogeneous. A perfusion defect was noted during retrograde cardioplegia in the right ventricular wall and in a portion of the posterior wall of the left ventricle in 4 of 6 hearts. Phosphorus 31 spectra showed that at the end of 45-minute retrograde cardioplegia, myocardial intracellular pH was 6.83 +/- 0.17 and phosphocreatine was 53.5% +/- 27% of its prearrest value. The adenosine triphosphate level, however, remained normal throughout the retrograde cardioplegia period. Last, the hearts subjected to retrograde cardioplegia or antegrade cardioplegia showed similar and complete metabolic and functional recovery during reperfusion. CONCLUSIONS: Retrograde cardioplegia provides heterogeneous perfusion. Its ability to protect the right ventricular myocardium is poor and varies between individuals. Myocardial perfusion provided by retrograde cardioplegia is slightly less than that needed to sustain normal myocardial energy metabolism under normothermic conditions.

Clinical and hemodynamic results with the St. Jude Medical cardiac valve prosthesis. A three-year experience.

Two hundred thirty-two consecutive patients (October 3, 1977, through December, 31, 1980) underwent aortic (AVR), mitral (MVR), or double (DVR) valve replacement with the St. Jude Medical (SJM) prosthesis. Operative mortality for the entire group was 7.3%. There was 100% follow-up. Warfarin (Coumadin) anticoagulation was recommended for all patients. There were no cases of mechanical failure. The incidence of thromboembolism was 0.6/1,000 patient-months for those with AVR, 3/1,000 patient-months for those with MVR, and 0% for those with DVR. Thrombosis of a prosthesis occurred in two patients with DVR. Clinically significant hemolysis occurred in three patients with paravalvar leaks following MVR. Late postoperative prosthetic infection has not occurred. Postoperative catheterization studies in 33 patients revealed no transvalvular gradient at rest in 21 patients. The remainder of the patients catheterizd had low transvalvular gradients. There was a minimal increase in transvalvular gradient with exercise. The SJM cardiac valve is a viable alternative in the surgical therapy of valvular heart disease.

Cardiac surgery in geriatric patients.

From June, 1960, to January, 1976, 157 patients 65 years or older had elective operations with cardiopulmonary bypass. Ninety-three patients had one or two valves replaced, 47 had coronary artery surgery, and 17 had both. The operative mortality rate was 22.6 percent (21 of 93), 19.1 percent (nine of 47), and 5.8 percent (one of 17), respectively. The over-all mortality rate was 19.7 percent (31 of 157). The mortality rate of patients of 65 to 69 years of age was 20 percent (22 of 110) and 19 percent (9 of 47) in patients 70 years or more. Ninety-four of these operations were performed within the last 3 years, with a reduction in patients' mortality rate to 9.6 percent (nine of 94). A retrospective study revealed a significant correlation between operative mortality rate and preoperative heart size. We could find no correlation between operative mortality rate and diabetes, smoking history, or hyperlipidemia. The major causes of death were myocardial infarction (68 percent-21 of 31), pulmonary complications (35 percent-11 of 31), infections (29 percent-nine of 31), and renal failure (29 percent-nine of 31) or combinations thereof. The patients who died had 2.5 times the number of complications of the survivors. Ninety percent of our patients in the past 3 years have survived their operation. Therefore, elective cardiac operations can be performed with an acceptable mortality rate in patients over the age of 65 years.

Clinical use of the membrane oxygenator.

Since April 1973 we have treated nine patients with extracorporeal membrane oxygenation (ECMO), utilizing the spiral coil membrane lung. One patient is a long-term survivor. All patients except one showed substantial improvement in peripheral arterial oxygen tension. Four adults and two neonates were treated for critical hypoxia. Two patients were treated for cardiac failure but failed to show improved myocardial function. Complications involving perfusion circuitry, cannulation, chronic systemic heparinization, thrombocytopenia, and renal failure have been managed with minimal difficulty. However, irreversible pulmonary, neurologic, hepatic, or gastrointestinal damage due to hypoxia present before the institution of ECMO was associated with lethal complications. The ECMO has supplied adequate oxygenation to this group of nine critically hypoxic patients. Institution of ECMO at an earlier date in patients with critical hypoxia would provide a higher likelihood of survival.

Placement of pericardial drainage tube for the treatment of pneumopericardium in the neonate.

A method for resolving the life-threatening complication of neonatal pneumopericardium is described. In patients suspected of having this complication, needle aspiration of the pericardial sac should be performed to confirm the diagnosis. Then a tube should be inserted directly into the sac, attached to continuous-suction drainage, and allowed to remain in place until positive end-expiratory pressure is discontinued. The technique has not been associated with morbidity, mortality, or recurrence of pneumopericardium.

Influence of aspirin and dipyridamole on patency of coronary artery bypass grafts.

A prospective randomized trial was performed to determine if the administration of inhibitors of platelet function would improve the patency of coronary artery bypass grafts. Patients were operated on for intractable angina with angiographically demonstrable lesions. The left internal mammary artery (IMA) was used for bypass of lesions of the left anterior descending coronary artery (LAD). Saphenous vein grafts were used for the LAD if the IMA was inadequate and for all other vessels. Treated patients received 1,300 mg of aspirin and 100 mg of dipyridamole (Persantine) orally each day. Control patients received neither drug. Patients returned 3 to 6 months after operation for repeat angiography. Results were analyzed by chi-square. One hundred seventy-four patients entered the study from June, 1973, through December, 1975, and 113 were analyzed. In the control group, 66 patients had 27 IMA-LAD grafts and 93 saphenous vein grafts. In the treatment group, 47 patients underwent 18 IMA-LAD grafts and 75 saphenous vein grafts. Ninety-eight of the 120 grafts (82%) were patent in the control group, and 87 of 93 grafts (94%) were patent in the treatment group (x2 = 6.34, p less than 0.02). Of the 45 IMA-LAD grafts in both groups, only 1 was occluded, a patency of 98%. In the control group, 72 of 93 saphenous vein grafts (77%) were patent. In the treatment group, 69 of 75 (92%) were patent (x2 = 6.54, p less than 0.02). The results of the study show a 15% difference between the two groups in the early patency of saphenous vein grafts. We continue to use aspirin and dipyridamole to improve the patency of saphenous vein bypass grafts.

St. Jude Medical prosthesis: valve-related deaths and complications.

Despite the hemodynamic improvement in cardiac valve prostheses, valve-related deaths and complications have remained a substantial source of morbidity and mortality. This follow-up study was carried out in April, 1986, in a group of 816 patients who received 876 St. Jude Medical prostheses between October, 1977, and October, 1984. One hundred fifty-five patients (37%) of the 422 having aortic valve replacement (AVR) and 88 (29%) of the 300 having mitral valve replacement (MVR) had concomitant coronary artery bypass grafting, and 94 patients (12%) had miscellaneous procedures performed in addition to valve replacement. Sixty-three patients died within the operative period, an operative mortality of 7.7%. Follow-up was complete for 98% of the patients; the mean follow-up was 42 months. At that time, 87 more patients had died, a late mortality of 11.9%. There were 13 valve-related deaths (4 in the AVR group, 7 in the MVR group, and 2 in the miscellaneous group); the causes of death were thromboembolism (7), anticoagulant-related hemorrhage (2), valve thrombosis (2), prosthetic valve endocarditis (1), and perivalvular leak (1). There were 37 thromboembolic episodes (1.78/100 patient-years) and 67 anticoagulant-related hemorrhages (3.22/100 patient-years), 46% of which necessitated transfusion. The incidence of valve thrombosis was 0.6% (4 patients). Perivalvular leak and prosthetic valve endocarditis occurred in 7 patients (1.0%) and 5 patients (0.7%), respectively. Reoperation was carried out in 6 patients (0.8%), but only for perivalvular leak. There were no deaths, no complications, and no clinical evidence of malfunction of the prosthetic valve.(ABSTRACT TRUNCATED AT 250 WORDS)

Free-water clearance and the early recognition of acute renal insufficiency after cardiopulmonary bypass.

The predictive value of free-water clearance measurements for the early recognition of acute renal insufficiency was evaluated in 59 patients immediately following cardiopulmonary bypass. Blood urea nitrogen and serum creatinine measurements were taken before and after operation. Intraoperatively, immediately after completion of bypass, urine and serum samples were obtained for osmolality. Duration of bypass, urine output, degree of hemolysis, and quality of perfusion were recorded. Fifty-four patients developed no signs of renal insufficiency following bypass, and all had free-water clearance values equal to or less than -20 ml per hour. Five patients who had free-water clearance values equal to greater than -8 ml per hour developed manifestations of an acute renal insufficiency state. There were no false-negative or false-positive determinations. Consequently, free-water clearance measurements appear to be a reliable indicator of those patients who will develop renal insufficiency following cardiopulmonary bypass. Early recognition provides an opportunity immediately after operation for initiating treatment consisting of administration of diuretics, potassium restriction, and oliguric fluid regimens.

Effect of sodium nitroprusside during the payback period of cardiopulmonary bypass on the incidence of postoperative arrhythmias.

This study was designed to determine whether a sodium nitropruside infusion during the reperfusion (payback) period of cardiopulmonary bypass would minimize arrhythmias during the early postoperative period of coronary artery bypass surgery. A double-blind randomized study was carried out in 38 patients with no previous history of ventricular arrhythmias. Seventeen received 5% dextrose in water (D5W) and 21 received sodium nitroprusside at the rate of 2 microgram per kilogram per minute during the payback period. The pump flow was kept constant at 2.2 liters per square meter per minute, and mean pressure was maintained at greater than 50 mm Hg. There was a statistically significant difference between the two groups in the number of patients who developed ventricular arrhythmias (13 of 17, or 76%, in the D5W group versus 6 of 21, or 29%, in the sodium nitroprusside group; p less than 0.005). Twelve of the 13 patients in the D5W group experienced arrhythmias (6 ventricular tachycardia and 6 ventricular premature depolarization) within the first 24 hours, compared to 5 of 12 patients in the nitroprusside group (3 ventricular tachycardia and 2 ventricular premature depolarization). Only 1 patient in each group developed ventricular arrhythmia after the first postoperative day. One patient in each group experienced atrial arrhythmia during the first 24 hours. After 24 hours, atrial arrhythmias developed in 5 patients in the D5W group (35%) and 3 patients in the sodium nitroprusside group (17%) (p greater than 0.05). The arterial pH ranged from 7.35 to 7.55, with a Po2 greater than 70 torr and a serum potassium of 3.7 +/- 0.36 mEq per liter in the D5W group and 3.4 +/- 0.34 mEq per liter in the nitroprusside group during the period of arrhythmias. Sodium nitroprusside given during the payback period of cardiopulmonary bypass appears to minimize ventricular arrhythmias in the early postoperative period of coronary artery bypass surgery.

Should valve replacement and related procedures be performed in elderly patients?

The cases of 135 consecutive elderly patients 70 years old or older who had valve replacement and related surgical procedures from October, 1977, through April, 1982, were reviewed. There were 75 men and 60 women. The mean left ventricular ejection fraction was 50.16 +/- 5%. The overall operative mortality was 8% (11 patients). The early operative deaths were related mainly to cardiac failure, low cardiac output, sepsis, and renal and multiorgan failure. To assess the operative risk, these 135 patients were compared with 312 younger patients (less than 70 years old) who had undergone similar procedures during the same period. The operative mortality in this group was 5.2% (16). In-hospital complications included arrhythmia (13%), psychosis (7.4%), respiratory failure (6.7%), renal failure (6.7%), cerebrovascular accident (5.2%), myocardial infarction (4.4%), and reoperation for bleeding (2.2%). Wound dehiscence occurred in 1.5% of the patients, and pulmonary emboli and sepsis developed in 0.7%. Of these complications, only the incidence of cerebrovascular accident appeared to be more common in the elderly group (5.2% versus 2.8%), but it had no statistical significance (p = 0.18). A follow-up of 3,892 patient-months was completed in 98.4% of the survivors. There were 8 late deaths (6.4%). Six were related to the valve or to ongoing cardiovascular disease. Thirty-four patients subsequently required medical attention: 4 had bleeding because of the anticoagulant; 3 required a blood transfusion; and 27 were hospitalized. Six were admitted for related cardiac conditions and 7, for observation of other conditions; 14 underwent surgical procedures not related to the cardiovascular system.(ABSTRACT TRUNCATED AT 250 WORDS)

Development of a practical membrane lung system.

The purpose of this study was to evaluate a compact, single-pump membrane oxygenator system designed for both short-term open-heart procedures and long-term extracorporeal support. Work was directed at developing a compatible, disposable venous reservoir, fabricating a compact mounting board, determining acceptable priming volumes, and establishing safe and effective modes of setup and operation. Ten adult baboons undergoing total cardiopulmonary autotransplantation as part of a separate study were operated on using a 1.5 m2 Kolobow spiral-coil membrane system. Blood gases, oxygen transfer, extracorporeal blood flows, priming volume, and setup times were determined. In addition, 3 infant and 6 adult human subjects undergoing cardiac operations in which spiral-coil membranes of various sizes were used were also similarly studied. The data and experience from these studies suggest that the spiral-coil membrane system utilized is safe and effective in procedures requiring short-term cardiopulmonary bypass.