Small donor size does not negatively impact outcomes after deceased-donor renal transplantation

Higher body mass index (BMI) of deceased-donors is associated with poorer outcomes in transplant recipients. The effect of low donor BMI on recipient graft function is not clear. Scientific Registry of Transplant Recipients data on recipients of deceased-donor kidneys from 2000 to 2019 were categorized by donor BMI (donor BMI < 18, 18-27, and >27). Primary outcome was death-censored graft survival. The impact of multiple recipient and donor variables, including low donor BMI and the difference between donor and recipient BMI, was evaluated using a multivariate Cox proportional-hazards model. Low BMI donors (LBD) were more likely to be younger, female, and white (all P < .05). LBD were less likely to be Hispanic, diabetic, or have hypertension (all P < .001). LBD recipients were more likely to be younger and female (both P < .001). Low donor BMI was not significantly associated with recipient graft survival. Donor-recipient BMI difference did not correlate with an increased risk of graft failure. Similar results were obtained when donors were classified using body surface area (BSA). Small donor size in terms of BMI or BSA or a large discrepancy between donor and recipient size should not necessarily preclude transplantation of an otherwise acceptable kidney.     

The influence of donor characteristics on survival after heart transplantation

With improved immunosuppressive regimens, transplantation techniques, and postoperative care, heart transplantation (HTx) has been established as a definite therapy for end-stage heart disease. Because of a donor shortage, we have accepted marginal individuals. In this study, we identified donor-related factors influencing survival after HTx by retrospective analysis of recipient data after primary HTx from February 2002 to December 2006. The Cox regression model was used to examine the effects of the following variables on survival of 112 heart transplant recipients: demographic data of gender, age, body weight, donor-recipient body weight ratio; history of smoking, alcohol drinking, diabetes mellitus, hypertension, hepatitis B surface antigen, anti-hepatitis C virus antibody; donor condication before transplantation including catecholamine doses, hypotension, cardiopulmonary resuscitation, creatine MB isoenzyme of creatine kinase (CK-MB), tropinin I, and cold ischemic time of the allograft. Catecholamines and smoking showed significant influences on HTx survival. In our series, the percentage of donors receiving inotropic support before donation was 88% (n = 99), and the percentage of donors with a history of smoking was 25% (n = 28). There was no influence of donor status of diabetes, hypertension, or hepatitis B or C infection on postoperative survival. Our results showed that inotropic support of and a history of smoking by the donor were significant factors influencing posttransplant survival.     

Gender mismatch between donor and recipient is a factor of morbidity but does not condition survival after cardiac transplantation

We intended to evaluate the influence of sex mismatch between donor and recipient, which is still under much debate, on survival and comorbidities after cardiac transplantation. From November 2003 to December 2013, a total of 258 patients were transplanted in our center. From these, 200 receptors were male (77.5%) and constituted our study population, further divided into those who received the heart from a female donor (Group A) – 44 patients (22%) and those who received it from a male donor (Group B) – 156 (78%). Median follow‐up was 4.2 ± 3.0 years (1–10 years). The two groups were quite comparable with each other, except for body mass index, systolic pulmonary artery pressure, and transpulmonary gradient, which were significantly lower in Group A. A low donor/recipient weigh ratio (<0.8) was avoided whenever possible. Hospital mortality was not different in the two groups. During follow‐up, global survival was similar, as was survival free from acute cellular rejection and cardiac allograft vasculopathy. However, patients in Group A had decreased survival free from serious infections and malignant tumors. Allocation of female donors to male receptors can be done safely, at least in receptors without pulmonary hypertension and when an adequate donor/recipient weigh ratio is ensured.     

Cytomegalovirus antibody status of donor/recipient does not influence the incidence of bronchiolitis obliterans syndrome in lung transplantation.

BACKGROUND: We have previously reported that prophylaxis for cytomegalovirus (CMV) infection does not influence the incidence of bronchiolitis obliterans syndrome (BOS) at 2 years. The effect of CMV infection (without evidence of disease) on BOS is still not well understood. Moreover, the incidence and risk factors for development of BOS in CMV-antibody-negative donor/recipient matches in lung transplantation have not been described. The aim of this study is to determine the incidence of BOS in lung transplant patients with CMV-antibody-negative (-) donors (D) and recipients (R), and to evaluate the risk factors that predispose to BOS in this sub-group. METHOD: A retrospective study of data from the transplant database of our center was performed. All single-lung (SL), double-lung (DL) and heart-lung block (HL) transplant patients who survived >2 years post-transplant were included in the study group. They were grouped as follows: D(-)/R(-), n = 102; D(-)/R(+), n = 70; D(+)/R(-), n = 33, and D(+)/R(+), n = 92. RESULTS: The 3-year BOS-free survival rates were 65%, 56%, 58% and 67%, respectively, and the incidence rates of BOS at 5 years post-transplant in the different groups were 57%, 62%, 78% and 55% (p > 0.05). In the D(-)/R(-) group, the significant risk factor for developing BOS was three or more episodes of acute rejection (p = 0.02). The mean numbers of acute rejection episodes per 100 patients-days within the first 6 months were 1.28, 1.06, 0.50 and 1.11 (p < 0.001 overall) for the four groups, respectively. CONCLUSION: Although CMV is believed to be a risk factor for BOS, its absence did not affect the occurrence or incidence of BOS in lung transplant patients. The main risk factor for BOS in the CMV-antibody-negative population remains the number of acute rejection episodes within the first 6 months after transplantation.     

Effect of donor recipient age match on survival after first deceased donor renal transplantation

Donor-recipient age matching has been proposed as a means of improving overall outcomes in deceased donor renal transplantation. It was hypothesized that donor-recipient age matching would improve patient survival time in younger recipients while not adversely affecting patient survivals in older recipients because they seldom outlive their grafts. By use of data from United Network of Organ Sharing Standard Transplant and Analysis and Research Files 50,320 patients were identified who underwent a first deceased donor renal transplantation between January 1, 1990, and December 31, 1997. Adjusted patient survival and death-with-graft function patient survival were analyzed from the date of transplantation. Patient survival was affected by donor age for all recipient age groups, including recipients older than 55 yr. The effect of donor age on patient survival is greater than that seen with HLA matching. The effect of donor age on patient survival persisted even when censoring recipients in whom grafts failed before death, suggesting that both longevity and quality of graft function are important in patient survival. Donor-recipient age matching is occurring to a limited degree in this population. Donor-recipient age matching would improve survival in younger recipients but would adversely affect survival in older patients by reducing the availability of younger donor kidneys for this group. The issue of donor-recipient age matching needs to be debated among the public and transplantation community so that a logical and just system can be developed.     

Effect of donor heart damage on survival after transplantation

Evaluation of the functional condition of the heart prior to its removal from the donor or after transport to the recipient is difficult. Biopsies of the myocardium allow serial assessments to be made throughout this period, but suffer from the disadvantage that the average analysis of biopsies has only a tenuous connection with physiological function. Quantitative birefringence measurements (QBM), on the other hand, assess the ability of myocardial fibres to respond to ATP and calcium and have been shown to correlate well with measurements of cardiac function (P<0.001). A prospective study of myocardial biopsies before excision, after transport and again after transplantation, using quantitative birefringence measurement of biopsies of the heart has recenty been completed. These studies have shown evidence of impaired myocardial function in 73 (43%) of 172 donor hearts studied prior to excision, with a further 27% showing significant deterioration during storage and transport to the recipient. Biopsy assessments therefore indicated that at the moment of implantation, only 30% of the donor hearts were normal. Functional assessment of the biopsies by QBM correlated with early clinical outcome of transplantation (P<0.001). Longer term follow-up of the recipients (up to 5 years) has shown that the mortality of recipients of hearts with impaired function before transplantation is significantly increased (44% of 120) compared with that of recipients of undamaged hearts (6% of 52, P<0.001).     

Laparoscopic organ retrieval for living donor liver transplantation does not prevent graft injury

The cause of transplant failure may be difficult to define. However, organ retrieval before preservation and transplantation is an important factor. Organ manipulation during harvesting, which is inevitable with most techniques, leads to injury upon reperfusion including microcirculatory disturbances. Recently, laparoscopic organ retrieval has been successfully performed for human living donor liver transplantation (LDLT). Pneumoperitoneum for laparoscopy changes the pattern of hepatic blood flow. To study the effects of pneumoperitoneum on the graft prior to cold storage, livers from Sprague-Dawley rats underwent pneumoperitoneum with an intra-abdominal pressure of 8 mm Hg for 90 minutes. Subsequently, intravital microscopy was performed to assess intrahepatic microcirculation and transaminases were measured. Serum transaminases increased 1.5-fold compared with sham controls (P < .05). Intrahepatic microcirculation was significantly disturbed immediately after pneumoperitoneum. If this is confirmed in humans, laparoscopic organ retrieval for LDLT would be expected to decrease graft quality and not be beneficial in liver transplantation.     

Cardiomyoplasty does not preclude heart transplantation.

Stimulated skeletal muscle grafts have been proposed to improve left ventricle function in patients with severe myocardial failure. In 1 particular case reported here, however, the postoperative functional improvement was only transient and disabling heart failure recurred after 9 months in spite of a vigorous latissimus muscle contraction. Heart transplantation was proposed to this patient and performed successfully. Technically, the key to heart removal depends on the retrograde dissection of the ventricular cavities, starting from the right atrioventricular groove. The intraoperative observations confirmed the viability of the latissimus dorsi muscle, inefficient on a highly dilated cardiomyopathy. Histopathological examination of the latissimus dorsi muscles showed that the transformation process of the stimulated muscle was good. Thus, severe cardiac dilatation seems to be one of the limitations of cardiomyoplasty. Cardiomyoplasty, when it fails, does not preclude heart transplantation. The histochemical studies confirm the electrophysiologic principle of cardiomyoplasty in humans.     

Heart and liver transplantation. Consistent survival after prolonged donor heart preservation.

Twelve dogs underwent orthotopic cardiac transplantation after donor heart preservation for 24 hr in a hypothermic hypertonic intracellular solution. Donors were divided into two groups: continuous oxygenated perfusion and nonperfusion. After 24 hr, transplantation was performed. All six perfused and four nonperfused donors hearts survived a 24-hr postoperative period. Survivors had normal cardiac output, right and left atrial pressures, and aortic pressures. After transplantation, all perfused hearts demonstrated mild left ventricular damage while nonperfused hearts had severe damage. Hypothermic hypertonic intracellular perfusion may allow improved protection for short-term myocardial preservation and survival after extended myocardial preservation.     

Assessing donor organ quality according to recipient characteristics in lung transplantation

ObjectiveThere is a shortage of donor lungs relative to need, but overall donor organ utilization remains low. The most common reason for refusal is organ quality, but the standards applied to selection vary. In this study we sought to characterize differences in lung utilization according to quality across several clinically distinct recipient pools.MethodsData on donor lungs recovered (April 2006 to September 2019) were extracted from the Scientific Registry of Transplant Recipients database. Organs were classified as ideal, standard, or extended quality according to their poorest metric among selected parameters. Subanalyses were performed on the basis of procedure type, age, lung allocation score, era, and alternative definitions of extended quality. Recipient traits and survival according to organ quality were assessed.ResultsOf 156,022 lungs analyzed during the study period, 25,777 (16.5%) were transplanted. There was no difference in quality distribution for single and bilateral transplants. Young candidates were more likely to receive ideal (14.7% vs 12.3%) or standard (9.5% vs 8.2%) lungs, but not extended lungs (75.9% vs 79.5%; all P < .01). Absolute differences in distribution according to lung allocation score quartile were small (<2%). Extended quality donor utilization increased over time. Survival according to donor category was similar at 1 and 3 years post transplant in unadjusted and Cox regression analyses.ConclusionsExtended quality lungs comprise an increasing share of transplants in a national sample. Organ selection varies according to recipient age and lung allocation score. However, absolute differences in quality distribution are small, and adverse effects on outcomes are limited to organs with multiple extended qualifying characteristics.     

Changing donor and recipient demographics in a heart transplantation program: influence on early outcome

BACKGROUND: The purpose of this study was to investigate whether broadening acceptance criteria for donor hearts and changing recipient demographics resulted in an increased perioperative morbidity and mortality in a heart transplant program. METHODS: Donor and recipient data of 137 consecutive heart transplants performed from 1987 to 2001 were retrospectively analyzed and divided into three equal eras, each of 5 years: 1987 to 1991, 1992 to 1996, and 1997 to 2001. Multivariate analyses of recipient and donor demographics and operative factors were performed to identify the predictors of low cardiac output, intraaortic balloon pump utilization, 30-day mortality, and duration of intensive care and hospital stay. RESULTS: Significant increases in number of female recipients (p = 0.025), cardiopulmonary bypass (p < 0.001), recipient cross-clamp (p < 0.001), donor age (p = 0.009), donor ischemic times (p < 0.001), use of cardioplegia (p < 0.001) and the bicaval technique (p < 0.001), brain death to retrieval time (p = 0.006), and need for postoperative dialysis were observed for the three study periods, whereas length of intensive care and hospital stay decreased. Female donor (odds ratio [OR], 2.4; 95% confidence interval [CI], 1.0 to 5.7) was identified as a risk factor for low cardiac output. Female donor (OR, 3.7; 95% CI, 1.3 to 10.7), donor cardiac arrest (OR, 6.4; 95% CI, 1.6 to 25.9), and cardiopulmonary bypass time more than 2 hours (OR, 7.6; 95% CI, 2.1 to 28.1) were associated with increased intraaortic balloon pump utilization. Intensive care stay was prolonged by the biatrial technique (OR, 3.9; 95% CI, 1.3 to 11.9) and reduced by the use of cardioplegia (OR, 0.3; 95% CI, 0.1 to 0.9), longer cardiopulmonary bypass (OR, 0.2; 95% CI, 0.1 to 0.6) and aortic cross-clamp times (OR, 0.1; 95% CI, 0.03 to 0.6). CONCLUSIONS: Although a number of significant changes were observed during the study period, no donor, recipient, or operative factors influenced 30-day mortality. This study justifies our current donor and recipient selection policies.