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Biomedical subjects

B A Reitz

Publications and source records attributed to B A Reitz.

At least 109 records · Page 6Linked to original sources
PubMed1990

Heart and heart-lung transplantation at the Johns Hopkins Hospital.

Since 1983, 120 patients have undergone heart transplantation and 18 patients have had heart-lung transplants at our institution. Transplantation is limited only by donor referrals but relaxation of donor criteria has increased donor availability. Immunosuppression currently consists of a 3-drug protocol of CsA, Aza, and P. Our current 1- and 5-year survival rates for heart transplants are 85% and 66%, respectively. The 1-year survival for heart-lung transplantation is 53%. Research continues in many areas of transplantation. The development of coronary artery disease in grafted hearts remains a problem. We have found that older donor age and Cmv infection are significant predictors of developing coronary disease. Routine successful extended heart-lung preservation has been difficult to achieve. A successful technique of prolonged preservation would allow for better matching, reduced logistics, and, potentially, increased numbers of donor organs.

Age Factors↗
PubMed1990

The effective treatment of postpericardiotomy syndrome after cardiac operations. A randomized placebo-controlled trial.

Although the postpericardiotomy syndrome is a common complication of cardiac operations, the most effective drug regimen for the treatment of this condition has not been established. The present study was designed to evaluate the effectiveness of nonsteroidal antiinflammatory drugs (NSAIDs) in the treatment of postpericardiotomy syndrome, in a double-blind, placebo-controlled randomized trial with a 10-day course of ibuprofen or indomethacin. Of 1019 adult patients undergoing cardiac operations during a 14-month period, a diagnosis of postpericardiotomy syndrome was made in 187, and 149 were enrolled in the study. Diagnosis was based on the presence of at least two of the following: fever, anterior chest pain, and friction rub. Drug efficacy was defined as the resolution of at least two of these criteria within 48 hours of drug initiation. Ibuprofen and indomethacin were 90.2% and 88.7% effective, respectively, and both were significantly more effective than placebo (62.5%, p = 0.003). The occurrence of side effects, including nausea, vomiting, renal failure, and fluid retention, was low in all groups (13.1% for ibuprofen, 16.1% for indomethacin, and 16.7% for placebo [p = not significant). Length of hospital stay, incidence of ischemic events, and accumulation of significant pericardial effusions were similar in all groups. The results of this study demonstrate that both ibuprofen and indomethacin provide safe and effective symptomatic treatment for postpericardiotomy syndrome.

Cardiac Surgical Procedures↗
PubMed1990

Hemorrhagic infarction of hilar lymph nodes associated with combined heart-lung transplantation.

The histologic changes in lymph nodes transplanted during combined heart-lung transplantation were examined. We studied at autopsy nine patients who had received a total of 10 heart-lung transplants. Hemorrhagic infarction of hilar nodes was found in eight of the 10 transplanted lungs. Pulmonary parenchymal pathologic changes associated with lymph node infarction included acute rejection (two cases), chronic rejection with bronchiolitis obliterans (two cases), and pneumonia (four cases). In one of the transplants without lymph node infarction there was chronic rejection with bronchiolitis obliterans and in another there was evidence of bronchopneumonia. The hemorrhagic lymph node infarction seen in the recipients of combined heart-lung transplant's may be directly attributable to the interruption of bronchial arteries and veins by the surgical procedure. At present the possible contribution of node infarction to postoperative morbidity or mortality is unknown.

Adolescent↗
PubMed1990

Leukocyte depletion ameliorates free radical-mediated lung injury after cardiopulmonary bypass.

Activated leukocytes and oxygen free radicals have been implicated in the pathogenesis of lung injury associated with cardiopulmonary bypass. To determine whether leukocyte depletion could prevent this injury, we used a dog model simulating routine cardiac operations. Mongrel dogs (11 to 17 kg) were subjected to cardiopulmonary bypass with a bubble oxygenator and cooled to 27 degrees C. After aortic crossclamping and cardioplegic arrest for 90 minutes, control animals (n = 5) were rewarmed and weaned from bypass, and their condition was then stabilized for 90 minutes. Leukocyte-depleted animals (n = 5) had a leukocyte filter incorporated in the bypass circuit. During bypass, circulating leukocyte counts decreased by 60% in control dogs, and by 97% in leukocyte-depleted animals. Free radical generation (estimated by spectrophotometric assay of plasma conjugated dienes) was significantly reduced by leukocyte depletion during and after bypass. Total hemolytic complement activity and the titer of C5 decreased markedly immediately after the onset of bypass in both the control and leukocyte-depleted animals. Pulmonary function after bypass was better preserved in leukocyte-depleted animals. These data suggest that depletion of circulating leukocytes contributes to lung injury during cardiopulmonary bypass and is associated with increased oxygen radical activity, pulmonary edema, and vasoconstriction. Leukocyte depletion substantially reduced the pulmonary injury seen after cardiopulmonary bypass.

Animals↗
PubMed1989

Unique aspects of heart and lung transplantation exhibited in the 'domino-donor' operation.

During the past 2 decades various refinements in heart and lung transplantation procedures have taken place. Improved preservation methods, new immunosuppressive medications, and advances in technical capabilities have allowed innovative procedures to be performed. In May 1987 the first "domino-donor" operation was performed in the United States. A 28-year-old man with cystic fibrosis and end-stage lung disease received the heart and lungs of an anonymous donor after he donated his heart to a 38-year-old man with end-stage ischemic cardiomyopathy. The technical and logistical aspects of this transplantation procedure are described herein. Other unusual features of this case that are discussed include heart-lung transplantation for a patient with cystic fibrosis, the use of cardiopulmonary bypass to allow lung procurement and transplantation across long distances, and the current role of heterotopic cardiac transplantation.

Adult↗
PubMed1989

Transmission of retroviruses by transfusion of screened blood in patients undergoing cardiac surgery.

We determined the rates of seroconversion to human immunodeficiency virus type 1 (HIV-1) and human T-cell leukemia virus Type I (HTLV-I) in a cohort of patients receiving transfusions of blood components screened for antibody to HIV-1. Preoperative and postoperative serum samples were collected from 4163 adults undergoing cardiac surgery who received 36,282 transfusions of blood components. The postoperative samples from all patients were tested for serologic evidence of HIV-1 infection, and those that were positive were compared with the corresponding preoperative samples. One case of HIV-1 transmission by transfusion of screened blood components was identified; two preexisting HIV-1 infections were found. Samples from 2749 patients were tested similarly for serologic evidence of HTLV-I infection; these patients received 20,963 units of blood components. Five new cases and two preexisting cases of HTLV-I infection were detected. The observed risk of HIV-1 transmission by transfusion was 0.003 percent per unit; the risk of HTLV-I transmission was 0.024 percent per unit. We conclude that there is a very small risk of HTLV-I infection from transfused blood products that have been screened for antibodies to HIV-1, but that it is nearly 10-fold higher than the risk of HIV-1 infection.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Exploratory analysis of time-dependent risk for infection, rejection, and death after cardiac transplantation.

Data from 95 heart transplantations performed at The Johns Hopkins Hospital from July 1983 to October 1988 were analyzed to detect patterns of morbidity and mortality. Using nonparametric techniques, hazard functions were determined for all deaths and for deaths due to infection or rejection. The rates of rejection and infection (episodes per patient-month) were determined within each of ten intervals following transplantation. A total of 19 deaths, 281 rejection episodes, and 180 distinct infections were available for analysis during a follow-up of 1 to 62 months. The hazard function for rejection appeared biphasic, with a rapidly decelerating early phase during the first year followed by a constant late phase. The hazard function for infection was triphasic, with a delayed, decelerating early phase, a period of increased risk approximately 2 years after operation, and finally a late constant phase. Both infection and rejection rates (episodes per patient-month) were biphasic, with rapidly decelerating early phases and constant late phases. Multiple regression analysis demonstrated that eventually nonsurviving patients had significantly higher rates of rejection and infection during both the early and late phases compared with survivors. The increased rate of rejection among nonsurvivors was evident throughout follow-up, although no deaths were attributable directly to rejection after the first 8 months. These data suggest that a complex interrelationship between infection and rejection determines late survival after cardiac transplantation and that aggressive treatment of late rejection predisposes toward death from infection.

Actuarial Analysis↗
PubMed1989

Cardiopulmonary bypass with profound hypothermia. An optimal preservation method for multiorgan procurement.

Numerous techniques have been devised for the harvesting of individual organs during a multiorgan procurement operation. Cardiopulmonary bypass with profound hypothermia (PH) has been employed in successful harvesting of heart-lung, kidney, pancreas, and liver grafts. This report summarizes our experience using CPB-PH for the harvesting of multiple organs from 10 brain-dead donors during the period from July 1983 to January 1988. Organs harvested included 10 heart-lungs, 17 kidneys (3 kidneys were not harvested due to anatomy and elevated creatinine), 1 liver, and 1 pancreas. Mean ischemic time for the distantly procured heart-lung grafts was 281 +/- 10 min. Adequate pulmonary function, as assessed by arterial blood gases, was observed in each heart-lung recipient (mean PO2 was 119 +/- 46 mmHg, 164 +/- 47 mmHg, 130 +/- 30 mmHg, 114 +/- 26 mmHg at immediate post-CPB, 6 hr postop, 24 hr postop, and postextubation, respectively). Mean length of intubation was 34 +/- 8 hr. Mean creatinines of kidney recipients at days 2, 7, and current creatinine were 7.4 +/- 3.6 mg%, 3.6 +/- 2.4 mg%, and 1.6 +/- 0.66 mg%, respectively. Eight kidney recipients (47%) required dialysis, (2 patients required only a single dialysis). Ninety-four percent of the kidney transplant patients are alive, and 88% (15/17) have functioning kidneys. One liver and 1 pancreas were harvested during this time period. Preservation was satisfactory in both the pancreas (Johns Hopkins Hospital) and liver (Dr. Thomas Starzl, personal communication). The technique of CPB-PH has resulted in excellent function of heart-lung grafts. Follow-up of the transplanted kidneys, liver, and pancreas utilizing this technique shows equal or better function compared with standard techniques. This technique offers other advantages in addition to satisfactory multiorgan preservation. Placement of an unstable patient on CPB ensures adequate organ perfusion and allows for a gradual yet uniform cooling of all organ systems. Cooling to a core temperature of 10-15 degrees C requires 30 min, during which time preliminary intraabdominal and mediastinal dissection can be carried out. Following cessation of CPB and subsequent exsanguination, organs can be more easily dissected in a near-bloodless field. This technique does not preclude additional crystalloid organ flushing. Since multiorgan procurement occurs with virtually every donor, this technique may be the optimal method providing excellent preservation, ease of dissection, and better control of hemodynamics during the operation.

Cardiopulmonary Bypass↗
PubMed1989

Separation of craniopagus Siamese twins using cardiopulmonary bypass and hypothermic circulatory arrest.

Occipitally joined craniopagus Siamese twins were separated with the use of cardiopulmonary bypass and hypothermic circulatory arrest. The 7-month-old infants shared a large sagittal venous sinus that precluded conventional neurosurgical approach because of risk of exsanguination and air embolism. After craniotomy and preliminary exposure of the sinus, each twin underwent sternotomy and total cardiopulmonary bypass with deep hypothermia. Hypothermic circulatory arrest allowed safe division and subsequent reconstruction of the sinus remnants. Several unusual problems were encountered, including transfusion of a large blood volume from one extracorporeal circuit to the other through the common venous sinus, deleterious warming of the exposed brain during circulatory arrest, and thrombosis of both pump oxygenators. Both infants survived, although recovery was complicated in each by neurologic injury, cranial wound infection, and hydrocephalus. This case demonstrates the valuable supportive role of cardiopulmonary bypass and hypothermic circulatory arrest in the management of complex surgical problems of otherwise inoperable patients.

Brain Injuries↗
PubMed1989

Recovery of cardiopulmonary reflexes in monkeys undergoing heart-lung transplantation.

After heart-lung transplantation in primates, cardiopulmonary reflexes were tested and shown to be present. The Hering-Breuer and cough reflexes were tested, as well as responses to an inhaled respiratory stimulant, vasodilator, and an intravenous anticholinesterase and antimuscarinic agent. Recovery of these responses, except to the anticholinesterase agent, suggests that reinervation occurs in autotransplanted organs in primates. The Hering-Breuer reflex was present at 1.9 and 2.2 months after the operation in two animals subjected to autotransplantation. These cardiopulmonary reflex responses were also demonstrated in two allograft recipients studied at 15 and 16.9 months after the operation. Return of protective reflexes such as coughing may be an important mechanism to prevent aspiration pneumonitis and other complications in humans.

Ammonia↗
PubMed1989

Immunosuppression after heart transplantation: prednisone and cyclosporine with and without azathioprine.

Fifty-four patients (group I) underwent isolated heart transplantation between July 1983 and January 1987 and were immunosuppressed with oral prednisone and cyclosporine. Twenty-three patients (group II) were transplanted between January 1987 and June 1988 and were immunosuppressed with oral prednisone, azathioprine, and cyclosporine, with lower targeted cyclosporine blood levels. The groups were similar in sex distribution of both donors and recipients. Primary cardiomyopathy was the primary recipient diagnosis in two thirds of patients in both groups. Donor age, graft ischemic time, and length of recipient hospitalization after transplant were similar. There was a trend toward transplantation of older patients in group II, and group II patients were more likely to receive hearts from local donors. Actuarial survival at 24 months was 75% in group I and 92% in group II. Patients who had triple-drug immunosuppression had statistically less early rejection but more early infections that tended to be minor. Hypertension requiring treatment occurred in 63% of group I patients and 62% of group II patients within the first 9 months after transplantation. Elevation of serum creatinine greater than 2.0 mg/dl occurred in 34% of group I patients and 15% of group II patients. A triple-drug immunosuppressive protocol is associated with less early rejection but more early minor infectious episodes. Although the incidence of hypertension is not reduced, there is a trend toward less nephrotoxicity and better survival.

Actuarial Analysis↗
PubMed1988

In vitro studies of isolated supported human hearts.

We developed methods to revive human hearts, obtained at the time of cardiac transplantation, and study them in the physiology laboratory. The hearts were arrested with cardioplegic solution at the time of explanation and transported to the laboratory at 4 degrees C. The hearts were perfused with a human blood based solution whose flow rate, temperature, and ionic concentration were controlled. Six hearts with various endstage cardiomyopathies were revived in this manner. Once perfusion was started, the hearts maintained a steady contractile state for approximately 30 min during which time data could be collected. Within this time period we could measure end-systolic and end-diastolic pressure-volume relations, the time courses of contraction and relaxation, and the influence of heart rate and premature stimulation on contractile state. The results suggest that evidence of specific cellular abnormalities in human heart disease might be obtained from measurements of global ventricular performance. Furthermore, the type of abnormality identified, namely sarcoplasmic reticulum dysfunction, in several forms of cardiomyopathy was in concordance with results obtained in muscle bath studies of similarly diseased human and animal myocardium.

Cardiomyopathy, Dilated↗
PubMed1988

Donor core-cooling provides improved static preservation for heart-lung transplantation.

Twenty-three dairy calves underwent heart-lung allotransplantation after donor organs were procured using either donor core-cooling through cardiopulmonary bypass (CPB) or pulmonary artery flush (PAF) to assess which method provides optimal graft preservation. In Groups 1 (control) and 2, donors were cooled to 15 degrees C on CPB and organs were either immediately transplanted (Group 1) or stored in saline solution (4 degrees C) for 4 hours (Group 2) prior to transplantation. In Group 3, donors were pretreated with prostaglandin E1 prior to PAF with modified Euro-Collins solution. Organs were stored in saline solution (4 degrees C) for 4 hours and were then transplanted. Acute cardiopulmonary function following transplantation was assessed by the ratio of end-systolic pressure to end-systolic dimension, extravascular lung water (EVLW), lung compliance, arterial oxygenation, and lung biopsy. Cardiac function after the transplantation procedure was similar in all groups, but EVLW values and lung biopsy scores were worse after PAF. Arterial O2 tension appeared lower after PAF, but not significantly so. Core-cooling provides superior static preservation and thus improved graft function in the acute bovine model.

Animals↗