Liver transplant outcomes after ex vivo machine perfusion: a meta-analysis.

BACKGROUND: The pressure on liver-transplant programmes has expanded the usage of extended-criteria allografts. Machine perfusion may be better than conventional static cold storage (SCS) in alleviating ischaemia-reperfusion injury in this setting. Recipient outcomes with hypothermic or normothermic machine perfusion were assessed against SCS here. METHODS: A search in MEDLINE, EMBASE and Scopus was conducted in February 2021. Primary studies investigating ex vivo machine perfusion were assessed for the following outcomes: morbidity, ICU and hospital stay, graft and patient survival rates and relative costs. Meta-analysis was performed to obtain pooled summary measures. RESULTS: Thirty-four articles involving 1742 patients were included, of which 20 were used for quantitative synthesis. Odds ratios favoured hypothermic machine perfusion (over SCS) with less early allograft dysfunction, ischaemic cholangiopathy, non-anastomotic strictures and graft loss. Hypothermic machine perfusion was associated with a shorter hospital stay and normothermic machine perfusion with reduced graft injury. Two randomized clinical trials found normothermic machine perfusion reduced major complication risks. CONCLUSION: Machine perfusion assists some outcomes with potential cost savings.

Does post-mastectomy radiation therapy worsen outcomes in immediate autologous breast flap reconstruction? A systematic review and meta-analysis.

BACKGROUND: There is great uncertainty regarding the practice of immediate autologous breast reconstruction (IBR) when post-mastectomy radiotherapy (PMRT) is indicated. Plastic surgery units differ in their treatment protocols, with some recommending delayed breast reconstruction (DBR) following PMRT. IBR offers significant cosmetic and psychosocial benefits; however, the morbidity of flap exposure to radiation remains unclear. OBJECTIVE: The aim of this review was to comprehensively analyze the existing literature comparing autologous flaps exposed to PMRT and flaps with no radiation exposure. METHODS: A comprehensive search in MEDLINE, EMBASE and CENTRAL databases was conducted in November 2020. Primary studies comparing IBR with and without adjuvant PMRT were assessed for the following primary outcomes: clinical complications, observer-reported outcomes and patient-reported satisfaction rates. Meta-analysis was performed to obtain pooled risk ratios of individual complications. RESULTS: Twenty-one articles involving 3817 patients were included. Meta-analysis of pooled data gave risk ratios for fat necrosis (RR = 1.91, p < 0.00001), secondary surgery (RR = 1.62, p = 0.03) and volume loss (RR = 8.16, p < 0.00001) favoring unirradiated flaps, but no significant difference was observed in all other reported complications. The no-PMRT group scored significantly higher in observer-reported measures. However, self-reported aesthetic and general satisfaction rates were similar between groups. CONCLUSION: IBR should be offered after mastectomy to patients requiring PMRT. The higher risks of fat necrosis and contracture appear to be less clinically relevant as corroborated by positive scores from patients developing these complications. Preoperative and intraoperative measures should be taken to further optimize reconstruction and mitigate post-radiation sequel. Careful management of patients' expectations is also imperative. LEVEL OF EVIDENCE: Level III.