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H T Bahnson

Publications and source records attributed to H T Bahnson.

At least 37 records · Page 2Linked to original sources
PubMed1987

Cardiac transplantation: improved quality of survival with a modified immunosuppressive protocol.

The effects on renal function on two different immunosuppressive protocols were evaluated retrospectively in two subsequent groups of heart transplant recipients. In group I, cyclosporine was given before the procedure at a loading dose of 17.5 mg/kg and then continued after the procedure to keep a whole blood level about 1000 ng/ml. In group II, cyclosporine was started only after the procedure at a lower dosage and was complemented by azathioprine, which was used for the first postoperative week. Group II showed a better perioperative renal function as determined by serum blood urea nitrogen and serum creatinine levels. Group II also showed a significant decrease of chronic nephrotoxicity secondary to long-term therapy with cyclosporine. Despite this improvement in late renal function, group II still shows a slow rise in serum creatinine. We think that even these lower dosages of cyclosporine can cause chronic nephrotoxicity and that further modification of the immunosuppressive regimen is required to completely abolish this toxic side effect.

Actuarial Analysis↗
PubMed1986

The contrasting effects of cyclosporin-A and azathioprine on arterial blood pressure and renal function following cardiac transplantation.

The effects of cyclosporin-A and azathioprine on the postoperative development of systemic hypertension and renal dysfunction in patients undergoing cardiac transplantation were compared retrospectively in 18 patients receiving cyclosporin-A and in 12 patients receiving azathioprine. Twelve months postoperatively, the average mean blood pressure was 116 +/- 13 mm Hg and 98 +/- 7.5 mm Hg; the average preoperative serum creatinine was 1.2 +/- 0.3 mg% and 1.5 +/- 0.3 mg%; and the postoperative serum creatinine was 2.2 +/- 0.8 mg% and 1.1 +/- 0.2 mg% (P less than 0.0001) in the cyclosporin-A-and azathioprine-treated groups respectively. Hemodynamic studies were done to characterize the de novo postoperative hypertension developing in the cyclosporin-A group. The pre- and postoperative cardiac output was 3.7 and 4.91/min, respectively (P less than 0.01). The pre- and postoperative systemic vascular resistance was 1707 and 1941 dynes sec X cm-5, respectively (P greater than 0.2). Peripheral renin activity and 24-hour urinary catecholamine excretion were not elevated. The mechanism of the hypertension developing in cyclosporin-A-treated patients is unknown, but is associated with normalization of cardiac output, an abnormally elevated systemic vascular resistance, and modest impairment of renal function. These findings are in marked contrast to azathioprine-treated patients, in whom postoperative hypertension and renal dysfunction do not occur. These observations implicate cyclosporin-A as the major contributing factor in the development of hypertension and renal dysfunction.

Adult↗
PubMed1986

Mortally ill patients and excellent survival following cardiac transplantation.

Cardiac transplantation was resumed in 1980 at the University Health Center of Pittsburgh. Generally accepted criteria for selection of patients were used, one being the expectation that survival would not reach 6 months. All of the initial recipients were in New York Heart Association Functional Class IV, but many were ambulant. We soon saw patients who were more clearly terminally ill. They were characterized by a systolic arterial pressure of less than 80 mm Hg, a cardiac index of less than 2 L/min/m2, evidence of reduced blood flow as indicated by urine output of less than 20 ml per hour, impaired mental function, and signs of decreased peripheral perfusion. The initial success of cardiac transplantation in these patients prompted us to reconsider selection criteria to include them among less strikingly ill candidates and to develop a therapeutic protocol designed to maintain peripheral perfusion and adequate renal and hepatic function until transplantation could be accomplished. Actuarial survival at 30 months for the group of terminally ill patients was 75% compared with 67% for the less critically ill group. Actuarial survival at 30 months for the combined group of 77 patients was 67%. Twenty-nine of the 33 mortally ill patients were alive and active at the time of writing, January, 1985.

Adult↗
PubMed1986

Development and organization of a multiple organ transplantation program.

Multiple organ transplantation has come of age. Indications are that it will continue to grow, if not flourish. The complexity of modern surgical care, its multiperson dependency, and the need for the surgeon to retain knowledge and involvement with his patient's care and problems are nowhere more evident than in multiple organ transplantation. Each organ presents its own associated challenges, the prime solution of which lies with a skillful and dedicated surgeon; but with all organs there are challenges of expectantly waiting patients, housing during the wait and for postoperative observation, procurement, erratic scheduling of the operating room, nursing, social service, immunosuppression, immunopathology, interest of hospital public relations and of the news media, and perennial care. This report concerns the growth and development of the multiple organ transplant program at the University Health Center of Pittsburgh and describes some answers to the challenges presented.

Academic Medical Centers↗
PubMed1986

Cardiac transplantation. Emerging from an experiment to a service.

Cardiac transplantation was resumed at the University Health Center of Pittsburgh in 1980 after a hiatus of 12 years. Prior to April 15, 1986, 270 hearts had been transplanted. Participants have been forced to reorder personal, professional, and institutional commitments to adapt to new demands of pre- and post-operative care and to develop flexibility in the operative scheduling of routine cardiac surgical cases. The actuarial survival has been 78, 69, and 64% at 1, 2, and 3 years. Much has been learned about evolving immunosuppression based on cyclosporine and of the allogenic response. An increasing proportion of recipients are mortally ill (54%), and for these urgent patients the wait for a donor organ continues to lengthen. The cardiac surgeon performing transplantations will need to grow with allied developments in xenotransplantation and mechanical cardiac support devices in order to keep pace with his evolving specialty.

Cyclosporins↗
PubMed1986

Early function of cardiac homografts: relationship to hemodynamics in the donor and length of the ischemic period.

Twenty-four of 124 heart transplant recipients in our study group died in the perioperative period. In five patients the cause of death was unknown even after postmortem examination. The possibility that the cause of death was due either to poor donor selection or poor preservation of the donor heart was evaluated by reviewing the length of ischemic time of the cardiac homografts and the need for inotropic support in the donors before the hearts were harvested. Results of our retrospective analysis indicate that inotropic support in the form of 2 to 10 micrograms/kg/min dopamine and an ischemic time of up to 4 hr do not influence the early survival of heart transplant recipients.

Adult↗
PubMed1985

Asynchronous rejection of heart and lungs following cardiopulmonary transplantation.

Eighteen patients have received 19 combined heart-lung allografts since March, 1982. During the maturation of our program of heart-lung transplantation, we have learned that isolated rejection of the lung can occur frequently and that exclusive dependence on the cardiac biopsy can be misleading. Of the 18 patients who received allografts, 10 are the basis for this report. The other patients were excluded because of death from excessive bleeding (1), inadequate lung preservation (2), an inability to differentiate rejection from infection (3), or an absence of rejection of either the heart or the lungs (2). Rejection of the lung was suggested, in the absence of clinical evidence of infection, by the radiographic appearance of a diffuse pulmonary infiltrate. It was confirmed by a prompt response to augmentation of maintenance immunosuppression with an intravenous pulse of methylprednisolone. The presence or absence of cardiac rejection was determined by the standard endomyocardial biopsy. Direct biopsy of the involved lung through a thoracotomy was performed in 4 patients so that a definitive histological diagnosis of rejection would reinforce the anticipated clinical diagnosis. The clinical course in 6 of the 10 patients plus the results of the open lung biopsy in 3 of them suggest that isolated rejection of the lung developed in the absence of cardiac findings. Patients responded within 12 to 24 hours to augmented immunosuppression with a dramatic improvement in the abnormal chest radiograph. In all 10 patients, either isolated lung or synchronous heart and lung rejection episodes were confined to the first six weeks after operation unless a severe alteration in the immunosuppression was made (2 patients).(ABSTRACT TRUNCATED AT 250 WORDS)

Biopsy↗
PubMed1985

Advantages of venous bypass during orthotopic transplantation of the liver.

Venous bypass restores normal hemodynamic physiology during the critical anhepatic phase of orthotopic transplantation of the liver. Its routine use in adults undergoing transplantation in Pittsburgh has resulted in lower operative blood losses, a lower frequency of postoperative renal failure, and a greater probability of survival for all but the highest risk patients. Because it allows for a longer anhepatic phase, the surgeon has the option of tailoring the native hepatectomy to the needs of the individual case, even to the point, in difficult cases, of obtaining most of the hemostasis after removal of the native liver, but before sewing in the donor organ. Selective use of bypass in children may offer similar advantages.

Evaluation Studies as Topic↗
PubMed1985

Morbidity of cytomegalovirus infection in recipients of heart or heart-lung transplants who received cyclosporine.

Forty-four heart and five heart-lung transplant recipients with cytomegalovirus (CMV) infection were investigated for risk factors associated with symptomatic CMV infection (17 patients) and CMV pneumonia (eight patients). Symptomatic infection was associated with primary rather than reactivated infection (P less than .005), younger age (P less than .005), heart-lung transplantation (P less than .001), and significant rises in titer of antibody to the early antigen of Epstein-Barr virus (P less than .001). Among recipients of heart transplants, patients with cardiomyopathy more often had symptomatic disease due to CMV (P less than .05). CMV pneumonia was associated with heart-lung transplantation and, in patients with primary CMV infection, earlier positive cultures for CMV after transplantation (P less than .02). CMV viremia was found in all patients with symptomatic infection, including the eight patients with CMV pneumonia, and the frequency of positive buffy coat cultures for CMV was significantly higher in patients with symptoms than in patients without symptoms (P less than .001). Neither symptomatic CMV infection nor CMV pneumonia was significantly associated with the use of antithymocyte globulin, restricted to therapy for rejection, and the use of high doses of acyclovir in 11 patients had no demonstrable impact on CMV culture positivity.

Acyclovir↗
PubMed1985

Combined transplantation of the heart and liver.

The technique of combined transplantation of the heart and liver is described and illustrated, emphasizing modifications that were used in a successful case. Two other unsuccessful attempts are reported, and the importance of relative size of donor and recipient is discussed. There may be an immunological advantage to transplanting two organs in combination from the same donor.

Adolescent↗
PubMed1985

Long-term hemodynamic follow-up of cardiac transplant patients treated with cyclosporine and prednisone.

To evaluate the long-term hemodynamic results in cardiac transplant patients treated with cyclosporine and prednisone, 19 patients were studied by cardiac catheterization and endomyocardial biopsy 13 +/- 3 months after transplantation. Immunosuppression consisted of 6 +/- 4 mg/kg/day cyclosporine and 20 +/- 8 mg/day prednisone. Eighteen patients were asymptomatic but had developed postoperative systemic hypertension (17 on antihypertensive therapy). These patients were compared with a normotensive control group of 18 patients without cardiovascular disease. Significant differences were found in heart rate; right atrial, pulmonary arterial, pulmonary arterial wedge, systemic arterial, and left ventricular end-diastolic pressures; cardiac index and stroke volume index; systemic and pulmonary vascular resistance; and end-diastolic volume index and left ventricular ejection fraction. The most frequent hemodynamic abnormalities included an elevated arterial pressure in 10 patients (56%), an elevated left ventricular end-diastolic pressure in six patients (33%), and a reduced ejection fraction in five patients (28%). Hemodynamic abnormalities tended to resolve or improve in the five patients restudied 2 years after transplantation. There was no significant relationship between fibrosis or inflammation on endomyocardial biopsy and hemodynamic abnormalities. We conclude that mild-to-moderate hemodynamic abnormalities are common in asymptomatic cardiac transplant patients receiving cyclosporine and prednisone.

Adult↗
PubMed1984

Heart-liver transplantation in a patient with familial hypercholesterolaemia.

A girl aged 6 years 9 months with severe heart disease secondary to homozygous familial hypercholesterolaemia underwent orthotopic cardiac transplantation and her liver was replaced with the liver of the same donor. In the first 10 weeks after transplantation serum cholesterol fell to 270 mg/dl from preoperative concentrations of more than 1000 mg/dl.

Child↗
PubMed1984

Venous bypass in clinical liver transplantation.

A venous bypass technique (BP) that does not require the use of systemic anticoagulation is used routinely at our institution in all adult patients during the anhepatic phase of liver transplantation (LT). Complete cardiopulmonary profiles were obtained in a subset of 28 consecutive cases. During the anhepatic phase while on bypass, mean arterial pressure, central venous pressure, and pulmonary arterial wedge pressure were maintained at prehepatectomy levels. Oxygen consumption fell secondary to a decrease in temperature and the removal of the liver. Consequently, cardiac index fell without an increase in arterial-venous O2 content difference, reflecting adequate tissue oxygenation. Compared with 63 patients in a previous series given LT without bypass (NBP), the 57 total BP patients experienced better postoperative renal function (p less than 0.001), required less blood use during surgery (p less than 0.01), and had better survival 30 days after LT. The equivalency of 90-day survival in these groups results from the lack of effect of BP on the long-term survival of patients considered at high risk for metabolic reasons. BP patients at high risk for technical considerations, however, survived LT whereas NBP patients did not. BP offers other advantages important in establishing LT as a service-oriented procedure.

Adult↗
PubMed1984

Powerful but limited immunosuppression for cardiac transplantation with cyclosporins and low-dose steroid.

Cyclosporin and low-dose prednisone provide powerful but limited immunosuppression for orthotopic cardiac transplantation. Optimal long-term survival was possible only with rescue therapy using rabbit antithymocyte globulin (RATG) when myocyte necrosis could not be reversed with pulse steroid therapy. The continued absence of rejection following rescue therapy with RATG in six of the last 19 patients is responsible for the improved 79% cumulative survival rate at 9 months compared to the 61% cumulative survival rate at 1 year for the initial 23 patients. The difference is that among the latter group, seven patients had persistent histologic rejection with focal myocyte necrosis which was not reversed with pulse therapy of steroids (hydrocortisone) or an increased dose of maintenance prednisone (30 to 40 mg/day). Three of these seven died of acute rejection within 3 months and four died between 8 and 13 months. Consequently, the cumulative survival rate of these 23 patients at 2 years was 41%. The projected 2 year cumulative survival rate of the 19 patients should not decrease greatly, as new episodes of rejection have not occurred beyond 3 months in either group.

Adolescent↗
PubMed1984

A flexible procedure for multiple cadaveric organ procurement.

Techniques have been developed which permit removal of the kidneys, liver, heart and other organs from the same donor without jeopardy to any of the individual grafts. The guiding principle is avoidance with all organs of warm ischemia. This is achieved by carefully timed and controlled infusion of cold solutions into anatomic regions, the limits of which are defined by preliminary dissection.

Cadaver↗