Renal injury
Postoperative kidney injury frequently results from the extended durations of HCA and extracorporeal circulation often involved in complex cardiac surgeries.1 Rezaei et al.estimate that acute kidney injury (AKI) occurs in up to 40% of FET cases, while Bashir et al. reports a pooled estimate of 15.5% (95% CI, 11.9-20.1) incidence.1, 5 Factors such as advanced age, elevated preoperative serum creatinine, pre-existing hypertension, intraoperative extracorporeal circulation ≥ 260 min, CPB ≥ 180 min, and implantation of a 4-branched Dacron graft with FET have been shown to increase the risk of AKI following FET arch repair.27, 28 6% (n=6) of patients in Yamamoto and colleague’s report suffered AKI and required dialysis following Z-0-FET, while Jakob et al. noted a permanent renal failure and AKI incidence rates of 16.7%.16, 17 50% (n=3) of patients in Jakob and colleague’s trial required haemodiafiltration postoperatively.17 In contrast, the incidence of postoperative haemodiafiltration following Z-2-FET has been shown to vary between 22% and 32%, and indeed Beckmann et al.highlighted 8% (n=8) of their patients suffered permanent kidney failure following Z-2-FET repair.12, 13, 22 It would be reasonable to suggest that that lower incidence of AKI and renal failure in Yamamoto and colleague’s report could be due to the shorter duration of CPB and extracorporeal circulation associated with proximalised aortic arch repair, yet one should recall that there has yet to be any large, multi-centre studies examining postoperative outcomes from Z-0-FET.27