Which level of preoperative glycated haemoglobin (HbA1c) affect early morbidity and mortality after cardiac surgery?

Abstract

Background Diabetics account for 34 per cent of all patients undergoing coronary artery bypass graft (CABG) surgery, and have higher rates of postoperative mortality. Furthermore, they are at risk for ICU admission postoperatively due to complications of hyperglycaemia, which in turn increases hospital mortality. Aims The purpose of this study was to evaluate the level of glycated haemoglobin (HbA1c) in patients undergoing cardiac surgery, and to establish it is an independent predictor for postoperative mortality and morbidity. Methods This retrospective study was conducted at King Fahd University Hospital. Files of 146 diabetic patients who underwent cardiac surgery in the period between September 2015 to June 2018 were included. One hundred and five patients met the inclusion criteria. Depending on the results of HbA1c preoperatively, patients were divided into 2 groups: Group A, with a HbA1c >=8.5 per cent, accounting for 33 patients, and Group B with a HbA1c <0.002). No significant difference was found when comparing length of hospital stay, wound infection postoperatively, reoperation, or readmission. Conclusion There was a significant difference in mortality postoperativly between the two groups, with patients who had higher HbA1c levels experiencing higher mortality. Since our sample size was small, we recommend that further studies be done in multiple centres.