Simple open-heart surgery protocol for sickle-cell disease patients: a retrospective cohort study comparing patients undergoing mitral valve surgery

Abstract

Abstract OBJECTIVES Sickle-cell disease (SCD) patients are considered to be at high risk from open-heart surgery. This study assessed the role of a simple sickling-prevention protocol. METHODS Perioperative non-specific and SCD-specific morbidity and 30-day mortality are investigated in a retrospective cohort study on patients undergoing isolated mitral valve surgery. Patients with and without SCD were compared. In the SCD cohort, a bundle of interventions was applied to limit the risk of sickling: ‘on-demand’ transfusions to keep haemoglobin levels of around 7–8 g/dl, cardiopulmonary bypass (CPB) with higher blood flow and perfusion temperature, close monitoring of acid–base balance and oxygenation. RESULTS Twenty patients with and 40 patients without SCD were included. At baseline, only preoperative haemoglobin levels differed between cohorts (8.1 vs 11.8 g/dl, P < 0.001). Solely SCD patients received preoperative transfusions (45.0%). Intraoperative transfusions were significantly larger in SCD patients during CPB (priming: 300 vs 200 ml; entire length: 600 vs 300 ml and 20 vs 10 ml/kg). SCD patients had higher perfusion temperatures during CPB (34.7 vs 33.0°C, P = 0.01) with consequently higher pharyngeal temperature, both during cooling (34.1 vs 32.3°C, P = 0.02) and rewarming (36.5 vs 36.2°C, P = 0.02). No mortality occurred, and non-SCD-specific complications were comparable between groups, but one SCD patient suffered from perioperative cerebrovascular accident with seizures, and another had evident haemolysis. CONCLUSIONS SCD patients may undergo open-heart surgery for mitral valve procedures with an acceptable risk profile. Simple but thoughtful perioperative management, embracing ‘on-demand’ transfusions and less-aggressive CPB cooling is feasible and probably efficacious.