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We developed a dextran-glucose-based extracellular perfusion solution (DGX) that supports limited aerobic metabolism to maintain cellular integrity of an inflated donor lung during long-term ischemia and a storage temperature of 10 degrees C. In a dog model, we compared respiratory and hemodynamic function of orthotopically transplanted left lungs preserved using this method (DGX, group I, n = 6) with function of those preserved with EuroCollins solution (EC) stored at a temperature of 4 degrees C (group II, n = 6). All lungs were inflated with room air and stored for 12 hr. Pulmonary function was monitored for 5 hr of reperfusion. Values expressed below are group means with standard deviation. Statistical significance was calculated using a two-tailed t test. For PO2 (mmHg) (FiO2 = 0.4), group I (EC): control = 193 +/- 8, 30 min p.o. = 87 +/- 20*, 300 min p.o. = 174 +/- 13*; and group II (DGX): control = 217 +/- 28, 30 min p.o. = 184 +/- 46*, 300 min p.o. = 248 +/- 5*. For pulmonary vascular resistance (dynes), group I: control = 389 +/- 22, 30 min p.o. = 1209 +/- 301, 300 min p.o. = 1025 +/- 204*; and group II: control = 401 +/- 31, 30 min p.o. = 522 +/- 129, 300 min p.o. = 458 +/- 137* (*P < 0.05 DGX vs. EC). Gas analysis performed on air samples taken from the ischemic donor lung immediately after harvest and after 12-hr storage showed (calculated as group means) a significant decrease of PO2 and a significant increase of PCO2, respectively. Histology of the lungs after 5 hr of reperfusion showed essentially normal-appearing lungs in the DGX group, whereas lungs in the EC group showed thickening of the intra-alveolar septi, marked cellular infiltration, and accumulation of protein-like material in the alveoli. In this study, preservation with DGX resulted in satisfactory respiratory and hemodynamic function of the transplanted lung even after 12 hr of ischemia. It does not cause an increase of pulmonary vascular resistance as seen after preservation with EC. Data from the intrabronchial air analysis of the donor lung suggest that aerobic metabolism continues even under preservation conditions.

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This study reports the evaluation of the validity and utility of the Medicare heart transplant center selection process, as outlined in its 1986 Heart Coverage Regulations. A total of 9401 heart transplants performed in the U.S. between 1986 and 1991 were analyzed. The outcomes assessed were mortality and the occurrence of infection during the hospital stay. Outcomes experienced by centers with and without Medicare approval were compared directly and following adjustment for patient risk factors. Patients at centers that satisfied the Medicare criteria experienced lower mortality. The risk-adjusted hazard ratio for death over the five years of observation was 0.874 (P = 0.005). The probability of death following a transplant at a Medicare-approved center was 7.0 +/- 0.4% at 30 days and 16.2 +/- 0.6% at one year, and 9.2 +/- 0.4% and 19.2 +/- 0.6%, respectively, at centers without Medicare approval (P = 0.001). The difference appeared to be principally associated with death within 30 days of admission due to nonspecific graft failure. The posttransplant infection rate at Medicare-approved centers was 0.743 (P < 0.001) but this result is strongly confounded with differences in reporting patterns of the two types of centers. Criteria used by HCFA identify medical centers where outcomes of heart transplantation, as measured by mortality, are superior. This difference is established early, persists over time, and is not attributable to the numerous risk factors considered in our models. Overall, the results of the present study suggest that "centers of excellence" can be identified through the evaluation of center characteristics and outcomes, and that this approach chosen by HCFA may have broad health care systems applications.

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An international series of pulmonary retransplantation was updated to identify the predictors of survival in the intermediate-term after reoperation for obliterative bronchiolitis. The study cohort included 32 patients with end-stage obliterative bronchiolitis who underwent retransplantation in 15 North American and European centers between 1988 and 1992. Five types of retransplantation procedures were done, including repeat ipsilateral single lung transplantation (7 patients), repeat contralateral single lung transplantation (8 patients), repeat double lung transplantation (3 patients), double lung transplantation after a previous single lung transplantation (3 patients), and single lung transplantation after a previous double lung or heart-lung transplantation (11 patients). The mean interval between transplants was 564 +/- 51 days (range 187 to 1589 days). Postoperative follow-up was 100% complete and the average follow-up in surviving patients was 678 +/- 63 days. Actuarial survival was 72%, 53%, 50%, 41%, and 33% at 1, 3, 6, 12, and 24 months, respectively. Survival did not differ according to the age, preoperative diagnosis, ambulatory or ventilator status, or cytomegalovirus serologic status of the recipient before reoperation. Life-table and Cox proportional hazards analysis identified the type of retransplantation procedure and the year of reoperation as significant (p < 0.05) predictors of postoperative survival. Actuarial survival was significantly better in patients without an old, retained contralateral graft after retransplantation and in patients who underwent reoperation between 1990 and 1992, as opposed to between 1988 and 1989. Infection was the most common cause of death at all time intervals after retransplantation, although all deaths beyond 2 years resulted from obliterative bronchiolitis of the second graft. Most surviving patients are in a satisfactory clinical condition, with a mean forced expired volume in 1 second of 59% +/- 13% of predicted (repeat double lung transplant recipients) or 41% +/- 6% of predicted (repeat single lung transplant recipients). We conclude that pulmonary retransplantation for obliterative bronchiolitis is associated with significantly worse survival than after primary lung transplantation. The absence of an old contralateral graft after retransplantation and reoperation after 1989 are important predictors of survival. Additional data and follow-up are required to determine the merit of pulmonary retransplantation for obliterative bronchiolitis.

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Previous studies have attempted to outline the efficacy of heart retransplantation in adults. A limited number of these retransplantation procedures have been performed in children; however, no study to date has evaluated the risk of heart retransplantation in this specific patient population. We conducted a retrospective review of 17 pediatric (non-neonatal) heart transplant recipients who subsequently underwent heart retransplantation. Thirteen male and four female patients underwent retransplantation at four different institutions between 1974 and 1992. Patient age at the time of primary transplantation ranged from 2 to 19 years (mean, 12.5 years) and from 3 to 30 years (mean, 16 years) at retransplantation. The time interval between transplantation procedures ranged from 2 days to 15.6 years and was not predictive of patient outcome. Follow-up after retransplantation ranged from 1 day to 11 years (mean, 2.8 years). All patients were New York Heart Association class 3 or class 4 at the time of retransplantation. After retransplantation all survivors were New York Heart Association class 1. No patient had mechanical device implantation or extracorporeal membrane oxygenation bridge-to-transplantation at primary transplantation or retransplantation. The indication for retransplantation was transplant coronary artery disease (TxCAD) in seven patients (41.2%), acute rejection in four (23.5%), chronic rejection in one (5.8%), chronic rejection associated with TxCAD in four (23.5%), and intraoperative donor organ failure in one (5.8%). No significant difference occurred in linearized rates of rejection or infection or in actuarial freedom from rejection or infection when secondary grafts were compared with primary grafts in patients undergoing retransplantation.(ABSTRACT TRUNCATED AT 250 WORDS)

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Data have been received by the Registry of the International Society for Heart and Lung Transplantation on more than 25,000 patients. Since 1984, patients ranging in age from newborn to 17 years have undergone 1668 heart transplantations, 186 heart-lung transplantations, and 109 lung transplantations. This report summarizes the data received regarding these pediatric thoracic transplant recipients.

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An international survey of redo lung transplantation was performed to identify the morbidity and mortality rates and factors correlating with increased or decreased survival after this procedure. Twenty institutions in North America and Europe participated, and the study cohort included 61 patients who underwent 63 redo lung transplantation operations. Patients undergoing a redo heart-lung transplantation were excluded. The indications for reoperation included obliterative bronchiolitis (32 patients), graft failure (14 patients), intractable airway problems (8 patients), severe acute lung rejection (5 patients), and miscellaneous complications (4 patients). Five types of retransplantation procedures were performed, including redo ipsilateral single lung transplantation (24 patients), redo contralateral single lung transplantation (11 patients), single lung transplantation after double lung or heart-lung transplantation (13 patients), redo double lung transplantation (8 patients), and double lung transplantation after a previous single lung transplantation (7 patients). Actuarial survival was 65%, 49%, 42%, 35%, and 32% at 1, 3, 6, 12, and 24 months, respectively; survival was significantly (p < 0.05) worse than that of first-time lung transplant recipients recorded in the International Society for Heart and Lung Transplantation Registry. Actuarial survival did not differ according to the original diagnosis of the recipients, the indication for reoperation, or the type of retransplantation procedure performed. Similarly, recipient cytomegalovirus status and ventilator status before reoperation did not affect postoperative survival. Trends toward an improved outcome were noted in patients who were ambulatory before reoperation and in those receiving an ABO identical, as opposed to ABO compatible, graft at reoperation. Life table and step-wise logistic regression analysis identified donor cytomegalovirus status at reoperation to be an important determinant of outcome, with significantly (p < 0.05) improved survival in the donor cytomegalovirus-negative group. Polymicrobial infection was the most common cause of death at all time intervals after reoperation. The presence of disseminated infection and established multiorgan failure was almost uniformly associated with a fatal outcome. We conclude that redo lung transplantation may be indicated only in well-selected patients with obliterative bronchiolitis, severe airway complications, or graft failure. Donor cytomegalovirus status at reoperation is an important predictor of survival. The presence of disseminated infection and established multiorgan failure should be contraindications to lung retransplantation.

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BACKGROUND: Current policies related to organ transplantation in the United States are designed to ensure that centers and physicians with experience in transplantation perform these procedures. It is essential to confirm the validity of such policies, since they may limit access to transplantation services. METHODS: To determine the relation between experience with heart transplantation and mortality after the procedure, we merged data from the registry of the International Society for Heart and Lung Transplantation with data from a survey that provided additional information about patients and transplantation centers. Our study included 1123 patients who received a heart transplant at one of 56 hospitals in the United States from 1984 through 1986. We used univariate and bivariate techniques, as well as logistic regression, to analyze our data. RESULTS: We observed an institutional learning curve for heart transplantation. Patients who received one of a center's first five transplants had higher mortality rates than patients who received a subsequent transplant (20 percent vs. 12 percent; P = 0.002; relative risk = 2.2; 95 percent confidence interval, 1.6 to 3.4). In addition, we found a correlation between the training of key personnel on the transplantation team and mortality at new transplantation centers. For example, new centers staffed by cardiologists with previous training in heart transplantation had lower mortality rates among heart-transplant recipients than centers without experienced cardiologists (7 percent vs. 16 percent; P = 0.001; relative risk = 2.7; 95 percent confidence interval, 1.3 to 5.9). By contrast, the previous training of the surgeons who performed transplantations was not related to the mortality rate associated with the procedure. CONCLUSIONS: Experience with heart transplantation is associated with a better outcome for patients after that procedure. Opportunities exist to refine transplantation policies on the basis of the experience of a center and its transplantation team and to develop similar policies for other forms of organ transplantation.

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Less than 25 years since the first human-human heart transplantation, the worldwide experience exceeds 16,000 heart and 1600 lung transplantations from more than 200 centers. Excellent results in heart transplantation have been achieved in a wide variety of patients. During the past few years, lung transplantation has come of age. The specific indications for each technique continue to evolve. Although much progress has been made, it is hoped that future developments in immunosuppression will solve the problems of chronic rejection and decrease the risk of infections. On behalf of the Society, we would like to take this opportunity to sincerely thank each of the participants throughout the world who took the time and care to submit their data to the Registry. Through this compilation of the world's experience, the state of the art in thoracic transplantation may be shared with the transplant community. The extensive Registry data base will permit risk assessment of thoracic transplant recipients while avoiding the problems associated with small sample sizes. Each participant's continued diligence in providing follow-up reports on all recipients is essential for an accurate evaluation of the long-term prognosis of heart and lung transplantation.

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The effects of hypothermic lung preservation were evaluated in 12 mongrel dogs receiving double lung allografts. Animals underwent transplant procedures after 12 hours of static preservation at 4 degrees C following pulmonary artery flush with 60 to 80 ml/kg cold modified Collins solution. Donors were pretreated with allopurinol and recipients with methylprednisolone and perireperfusion deferoxamine. Six donor animals received a PGE1 infusion (20 to 500 ng/kg/min) for 20 minutes before harvest at doses causing a significant reduction in pulmonary vascular resistance. After implantation, recipients were maintained at ventilator settings identical to those used in donors. A fixed FIO2 (0.4) was maintained, except for 15-minute periods of FIO2 1.0 that were used to measure left-to-right intrapulmonary shunt fraction (Qs/Qt) and alveolar-arterial oxygen gradients (PAO2-PaO2). Cardiopulmonary function was studied for 20 hours. Pretreatment with PGE1 resulted in reduced survival (p less than 0.05) and increased PAO2-PaO2 (p less than 0.05) and Qs/Qt (p less than 0.05) 30 minutes after reperfusion. After 60 minutes of reperfusion, mean arterial pO2 (FIO2 0.4) was 148 mm Hg in controls and 80.5 mm Hg in the PGE1 group (p less than 0.02). There was no significant difference in pulmonary vascular resistance, cardiac output, mixed venous oxygen saturation, airway resistance, compliance and physiologic dead space between groups at any time after implantation. After 20 hours of reperfusion, pO2 (FIO2 0.4) in the control group was well maintained at 140 (+/- 52) mm Hg. The method of lung preservation in control animals resulted in good survival and adequate gas exchange after 12 hours of ischemia and 20 hours of reperfusion.(ABSTRACT TRUNCATED AT 250 WORDS)

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Orthotopic heart transplantation continues to be a highly successful therapy for end-stage cardiac disease. Recent advances have extended the benefits of this procedure to neonatal patients. The number of patients undergoing single- and double-lung transplantation increases steadily and the indications for transplantation are being expanded. Evaluation of the early results indicates that patients undergoing lung transplantation for vascular disease do not fare as well as those undergoing transplantation for parenchymal disease. Presently, the results of retransplantation are far inferior to primary transplantation and require ongoing evaluation.

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During the past decade we have witnessed a continuing evolution in intrathoracic transplantation. The role of heart transplantation in end-stage heart disease has been well established; and combined heart-lung and lung transplantation techniques developed during the past 10 years have been applied to an expanding array of diseases associated with end-stage pulmonary failure. Recently a plateau in number of transplants per year has become evident. Although the areas of pediatric heart and single lung transplantation continue to expand, it appears that further overall growth in heart and lung transplantation is now limited by donor availability. Although operative mortality has shown gradual improvement, organ preservation and other intraoperative complications remain major factors associated with early death, especially in combined heart-lung and lung transplantation. Infection and rejection are the most common causes of late deaths for all types of intrathoracic transplantation. Although long-term survival has shown improvement over the past 10 years, an increasing number of patients now require retransplantation because of chronic rejection. Results with heart, combined heart-lung, and lung retransplantation, in operative mortality and in long-term survival, have not been as encouraging as with the primary transplant procedure. We await further developments in heart and lung transplantation during the new decade.

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The physiologic effects of 12-hour lung preservation were assessed in six mongrel dogs studied for 20 hours after double-lung allograft implantation. Donor animals were pretreated with allopurinol (30 mg/kg) and methylprednisolone (500 mg) intravenously at anesthesia induction. Heart-lung blocks were harvested after cardioplegic arrest, and a simple pulmonary artery flush of 4 degrees C modified Collins' solution was administered at 15 ml/kg/min. The lungs were ventilated with 100% nitrogen during flushing and inflation. Recipient animals received an infusion of deferoxamine (20 mg/kg) during implantation and were pretreated with methylprednisolone (500 mg) intravenously. All six implantations were technically successful. Two animals died of cardiac standstill 12 and 24 hours postoperatively. Gas exchange deteriorated after implantation compared with donor levels but remained in a range compatible with survival, and at 20 hours arterial oxygen tension (FiO2 0.4) was 138 +/- 91 mm Hg. Similar changes were seen in alveolar-arterial oxygen gradients and arterial-alveolar oxygen tension fraction. Elimination of carbon dioxide was satisfactory. Pulmonary venous shunt fraction rose significantly at the end of the study. Hemodynamic changes consisted of a gradual increase in pulmonary vascular resistance and a reduction in cardiac output. Lung mechanics also deteriorated, with a gradual rise in airway resistance and a fall in compliance. The double-lung model allows detailed assessment of the early effects of preservation and may have certain advantages over heart-lung models of preservation. The preservation technique warrants further study.

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