The Impact of Obesity on the Resolution of Hypertension Following Adrenalectomy for Primary Hyperaldosteronism.

BACKGROUND: This study aims to determine the impact of patient obesity on the resolution of hypertension and pill burden post-adrenalectomy for PA. Primary hyperaldosteronism (PA) is the most common cause of secondary hypertension that may be remedied with surgery (unilateral adrenalectomy). Obesity may independently cause hypertension through several mechanisms including activation of the renin-angiotensin-aldosterone pathway. The influence of obesity on the efficacy of adrenalectomy in PA has not been established. METHODS: This is a retrospective analysis of prospectively collected data on patients undergoing adrenalectomy for PA at a single, tertiary-care surgical centre from January 2015 to December 2020. Electronic health records of patients were screened to collect relevant data. The primary outcomes of the study include post-operative blood pressure, the reduction in the number of anti-hypertensive medications and potassium supplementation burden post-adrenalectomy. RESULTS: Fifty-three patients were included in the final analysis. There was a significant reduction in the blood pressure and the number of anti-hypertensive medications in all patients after adrenalectomy (p < 0.001). Of the 34 patients (64.2%) with pre-operative hypokalaemia, all became normokalaemic and were able to stop supplementation. However obese patients required more anti-hypertensive medications to achieve an acceptable blood pressure than overweight or normal BMI patients (p < 0.01). Multivariate logistic regression analysis showed that male gender and BMI were independent predictors of resolution of hypertension (p <0.01). CONCLUSION: Unilateral adrenalectomy improves the management of hypertension and hypokalaemia when present in patients with PA. However, obesity has an independent deleterious impact on improvement in blood pressure post-adrenalectomy for PA.

Utilisation of small paediatric donor kidneys for transplantation.

With the increasing need for kidney transplantation in the paediatric population and changing donor demographics, children without a living donor option will potentially be offered an adult deceased donor transplant of marginal quality. Given the importance of long-term graft survival for paediatric recipients, consideration is now being given to kidneys from small paediatric donors (SPDs). There exist a lack of consensus and a reluctance amongst some centres in transplanting SPDs due to high surgical complication rates, graft loss and concerns regarding low nephron mass and long-term function. The aim of this review is to examine and present the evidence base regarding the transplantation of these organs. The literature in both the paediatric and adult renal transplant fields, as well as recent relevant conference proceedings, is reviewed. We discuss the surgical techniques, long-term graft function and rates of complications following transplantation of SPDs. We compare graft survival of SPDs to adult deceased donors and consider the use of small paediatric donors after circulatory death (DCD) organs. In conclusion, evidence is presented that may refute historically held paradigms regarding the transplantation of SPDs in paediatric recipients, thereby potentially allowing significant expansion of the donor pool.

Rapid sampling microdialysis as a novel tool for parenchyma assessment during static cold storage and hypothermic machine perfusion in a translational ex vivo porcine kidney model.

BACKGROUND: Viability assessment during preservation is imperative to avoid unnecessary discard of marginal organs maximizing graft outcomes in kidney transplantation. To address this need, we have developed a novel system based on a rapid sampling microdialysis (rsMD) analyzer allowing continuous tissue monitoring and measurement of metabolic markers of cell damage. Our aim was to develop a tool that allows for accurate assessment of tissue metabolism and organ viability in the preservation period. METHODS: Twenty-two porcine kidneys subjected to 15 min of warm ischemia underwent either 24 h of static cold storage (SCS) or 10 h of hypothermic machine perfusion (HMP). After preservation, tissue temperature was allowed to passively increase to ambient temperature as an ischemic challenge. Cortical and medullary metabolism was monitored throughout with online measurements of lactate concentrations made every 60 s. RESULTS: On commencement of monitoring, lactate concentrations were successfully detected within 15 mins. During the initial 1.5 h, lactate concentrations were similar during SCS (65 µM) and HMP (124 µM, P > 0.05) but lower after 10 h of SCS (SCS: 68 µM versus HMP: 230 µM, P < 0.001). Warming data suggest a resilience of HMP kidneys to subsequent temperature induced ischemia compared to SCS kidneys. CONCLUSIONS: This preliminary study provides the baseline ischemic profile for porcine kidneys while validating the technique of rsMD as a tool for organ viability assessment during preservation. The data characterize metabolic differences between SCS and HMP preserved allografts and can help elucidate why HMP is clinically superior to SCS allowing development of interventions to augment these benefits.

Ureteric stenting in kidney transplants.

The routine use of ureteric stents after a kidney transplant for prophylactic measures is debatable. Concerns have been raised regarding the potential complications and costs of routine stenting. Here, we review the literature based on studies in favor of and against the routine placement of ureteric stents in kidney transplant patients. Some studies have shown a benefit to patients who have routine stents placed, while others have not shown this benefit but have highlighted the associated financial implications. The decision to stent renal transplant patients will depend on robust multicenter, randomized controlled trials being carried out, as well as both short-term and long-term cost analyses.