The Influence of Deep Hypothermic Circulatory Arrest on the Incidence of Postoperative Acute Kidney Injury After Pulmonary Endarterectomy

Background: Pulmonary endarterectomy (PEA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH) is performed using phases of deep hypothermic circulatory arrest (DHCA). DHCA has been discussed as a risk factor for cardiac surgery-associated acute kidney injury (AKI). The study analyzes the influence of the duration of DHCA on the incidence of postoperative AKI in patients undergoing PEA. Methods: This retrospective single-center cohort study included adult CTEPH patients who underwent PEA. The main exposure was DHCA at 18–20 °C core temperature. Primary endpoint was postoperative AKI defined by the KDIGO serum creatinine criteria. Secondary endpoints included severe postoperative AKI, major adverse cardiovascular events and mortality. Univariate and multivariate logistic regression models were performed for risk factor analysis. Results: Four hundred and eighty-three patients were included (mean age 61 ± 13 years). The incidence of postoperative AKI was 50%. Multivariate analysis showed no association between DHCA and AKI. Postoperative AKI was independently associated with chronic kidney disease (OR = 1.76, 95% CI = 1.05–2.95), age (OR = 1.02, 95% CI = 1.00–1.03), cardiopulmonary bypass (CPB) time (OR = 1.01, 95% CI = 1.01–1.02) and vasoactive-inotropic score (VIS) (OR = 1.05, 95% CI = 1.01–1.10). Patients with preoperative diuretics had a lower risk for postoperative AKI (OR = 0.44, 95% CI = 0.29–0.66). MACE were more frequent in patients with postoperative AKI (28.4% vs. 14.2%, p < 0.001), whereas 30-day and 1-year mortality did not differ. Conclusions: Results from this study indicate no influence of DHCA duration on occurrence of postoperative AKI. Risk factors identified for postoperative AKI were chronic kidney disease, age, CPB duration and VIS.