Using Laser Speckle Contrast Imaging to Quantify Perfusion Quality in Kidney and Pancreas Grafts on Vascular Reperfusion: A Proof-of-Principle Study.

The accuracy of intraoperative graft perfusion assessment still remains subjective, with doppler examination being the only objective adjunct. Laser speckle contrast imaging (LSCI) has been used to assess intraoperative blood flow in neurosurgery and in various surgical specialties. Despite its ability to accurately quantify perfusion at the microvascular level, it has not been clinically evaluated in kidney/kidney-pancreas transplantation for perfusion characterization. We aimed to evaluate the utility of LSCI and identify objective parameters that can be quantified at reperfusion. Methods: This study was registered in ClinicalTrials.gov (NCT04202237). The Moor FLPI-2 blood flow imager was used in 4 patients (1 Simultaneous Pancreas and Kidney, 2 deceased, and 1 living donor kidney transplants) during reperfusion to capture reperfusion data. The following parameters were measured: flux (average speed × concentration of moving red blood cells in the sample volume), doppler centroid, total and valid pixels, valid rate, and total and valid area. Flux data were analyzed with Moor FLPI analysis software. Results: The perfusion characteristics and flux images correlated with initial graft function. Conclusions: LSCI is a safe, noncontact imaging modality that provides real-time, accurate, high-resolution, full field blood flow images and a wide range of flux data to objectively quantify organ reperfusion intraoperatively in kidney/kidney-pancreas transplantation. This modality could be used to develop a robust numerical quantification system for the evaluation and reporting of intraoperative organ perfusion, and aid intraoperative decision-making. Perfusion data could be combined with biomarkers and immunological parameters to more accurately predict graft outcomes.

Selective Hepatic Vascular Exclusion versus Pringle Maneuver in Major Hepatectomy: A Systematic Review and Meta-Analysis.

Objectives: Mortality and morbidity following hepatic resection is significantly affected by major intra-operative blood loss. This systematic review and meta-analysis evaluates whether selective hepatic vascular exclusion (SHVE) compared to a Pringle maneuver in hepatic resection reduces rates of morbidity and mortality. Methods: A systematic review and meta-analysis were conducted according to the PRISMA guidelines by screening EMBASE, MEDLINE/PubMed, CENTRAL and SCOPUS for comparative studies meeting the inclusion criteria. Pooled odds ratios or mean differences were calculated for outcomes using either fixed- or random-effects models. Results: Six studies were identified: three randomised controlled trials and three observational studies reporting a total of 2,238 patients. Data synthesis showed significantly decreased rates of mortality, overall complications, blood loss, transfusion requirements, air embolism, liver failure and multi-organ failure in the SHVE group. Rates of hepatic vein rupture, post-operative hemorrhage, operative and warm ischemia time, length of stay in hospital and intensive care unit were not statistically significant between the two groups. Conclusion: Performing SHVE in major hepatectomy may result in reduced rates of morbidity and mortality when compared to a Pringle maneuver. The results of this meta-analysis are based on studies where tumors were adjacent to major vessels. Further RCTs are required to validate these results. Clinical Trial Registration: PROSPERO (CRD42020212372) https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=212372.

Liver Transplantation for Non-Resectable Liver Metastases from Colorectal Cancer: A Systematic Review and Meta-Analysis.

BACKGROUNDS: Colorectal liver metastases were historically considered a contraindication to liver transplantation, but dismal outcomes for those with metastatic colorectal cancer and advancements in liver transplantation (LT) have led to a renewed interest in the topic. We aim to compare the current evidence for liver transplantation for non-resectable colorectal liver metastases (NRCLM) with the current standard treatment of palliative chemotherapy. METHODS: A systematic review and meta-analysis of proportions was conducted following screening of MEDLINE, EMBASE, SCOPUS and CENTRAL for studies reporting liver transplantation for colorectal liver metastases. Post-operative outcomes measured included one-, three- and five-year survival, overall survival, disease-free survival and complication rate. RESULTS: Three non-randomised studies met the inclusion criteria, reporting a total of 48 patients receiving LT for NRCLM. Survival at one-, three- and five-years was 83.3-100%, 58.3-80% and 50-80%, respectively, with no significant difference detected (p = 0.22, p = 0.48, p = 0.26). Disease-free survival was 35-56% with the most common site of recurrence being lung. Thirteen out of fourteen deaths were due to disease recurrence. CONCLUSION: Although current evidence suggests a survival benefit conferred by LT in NRCLM compared to palliative chemotherapy, the ethical implications of organ availability and allocation demand rigorous justification. Concomitant improvements in the management of patients following liver resection and of palliative chemotherapy regimens is paramount.

Growth and renal function dynamics of renal oncocytomas in patients on active surveillance.

OBJECTIVES: To study the natural history of renal oncocytomas and address indications for intervention by determining how growth is associated with renal function over time, the reasons for surgery and ablation, and disease-specific survival. PATIENTS AND METHODS: The study was conducted in a retrospective cohort of consecutive patients with renal oncocytoma on active surveillance reviewed at the Specialist Centre for Kidney Cancer at the Royal Free London NHS Foundation Trust (2012 to 2019). Comparison between groups was performed using Mann-Whitney U-tests and chi-squared tests. A mixed-effects model with a random intercept for patient was used to study the longitudinal association between tumour size and estimated glomerular filtration rate (eGFR). RESULTS: Longitudinal data from 98 patients with 101 lesions were analysed. Most patients were men (68.3%) and the median (interquartile range [IQR]) age was 69 (13) years. The median (IQR) follow-up was 29 (26) months. Most lesions were small renal masses, and 24% measured over 4 cm. Over half (64.4%) grew at a median (IQR) rate of 2 (4) mm per year. No association was observed between tumour size and eGFR over time (P = 0.871). Nine lesions (8.9%) were subsequently treated. Two deaths were reported, neither were related to the diagnosis of renal oncocytoma. CONCLUSION: Natural history data from the largest active surveillance cohort of renal oncocytomas to date show that renal function does not seem to be negatively impacted by growing oncocytomas, and confirms clinical outcomes are excellent after a median follow-up of over 2 years. Active surveillance should be considered the 'gold standard' management of renal oncocytomas up to 7cm.

Roux-en-Y versus single loop reconstruction in pancreaticoduodenectomy: A systematic review and meta-analysis.

BACKGROUND: Post-operative pancreatic fistula (POPF) and delayed gastric emptying (DGE) both remain problematic complications following pancreaticoduodenectomy. This systematic review and meta-analysis evaluates whether Roux-en-Y compared to a single loop reconstruction in pancreaticoduodenectomy significantly reduces rates of these complications. METHODS: A systematic review and meta-analysis was conducted according to the PRISMA guidelines by screening EMBASE, MEDLINE/PubMed, CENTRAL and bibliographic reference lists for comparative studies meeting the predetermined inclusion criteria. Post-operative outcome measures included: POPF, DGE, bile leak, operating time, blood loss, need for transfusion, wound infection, intra-abdominal collection, post-pancreatectomy haemorrhage, overall morbidity, re-operation, overall mortality, hospital length of stay. Pooled odds ratios or mean differences with 95% confidence intervals were calculated using either fixed- or random-effects models. RESULTS: Fourteen studies were identified including four randomised controlled trials (RCTs) and 10 observational studies reporting a total of 2,031 patients. Data synthesis showed no statistically significant difference between the two groups in any of the outcome measures except operating time, which was longer in those undergoing Roux-en-Y reconstruction. DISCUSSION: Roux-en-Y is not superior to single loop reconstruction in pancreaticoduodenectomy but may prolong operating time. Future high-quality randomised studies with appropriate study design and sample size power calculation may be required to further validate this conclusion.

Kidney Transplantation From a 5-Day-Old Donor With a Single Functioning Kidney.

Kidney transplant restores renal function in eligible patients with end-stage renal failure who require renal replacement therapy. There remains a significant disparity between the demand and supply of suitable kidneys for transplant. In recent years, pediatric donors have formed an important area for expansion of the donor pool. However, neonatal donation (< 28 days) remains an underutilized resource. We describe a case of en bloc kidney transplant from a 5-day-old donor after circulatory death into an adult recipient. One kidney thrombosed almost immediately, leaving a single 4.5-cm, poorly functioning kidney. Eighteen months after transplant, the recipient has shown good function with the estimated glomerular filtration rate continuing to improve. This case demonstrates that a single neonatal kidney can grow and adapt to provide adequate renal function in an adult. This experience suggests that a single kidney from a neonate can sustain renal function in adults, and every effort should be made to maximize their use in transplant.