Perioperative ADministration of Dexamethasone And blood Glucose concentrations in patients undergoing elective non-cardiac surgery - the randomised controlled PADDAG trial

BACKGROUND The hyperglycaemic effect of dexamethasone in diabetic and nondiabetic patients in the peri-operative period is unknown. OBJECTIVE To assess the effect of a single dose of intra-operative dexamethasone on peri-operative blood glucose. DESIGN Multicentre, stratified, randomised trial. SETTING University hospitals in Australia and Hong Kong. PATIENTS A total of 302 adults scheduled for elective, noncardiac and nonobstetric surgical procedures under general anaesthesia, stratified by diabetes mellitus status, were randomised to receive placebo, 4 or 8 mg dexamethasone administered intravenously after induction of anaesthesia. MAIN OUTCOME MEASURES Maximum blood glucose within 24 h of surgery, and the interaction between glycated haemoglobin (HbA1c) and dexamethasone were the primary and secondary outcomes. RESULTS The median [IQR] baseline blood glucose in the nondiabetes stratum in the placebo (n=81), 4 mg (n=81) and 8 mg dexamethasone (n=77) trial arms were respectively 5.3 [4.6 to 5.8], 5.0 [4.7 to 5.4] and 5.0 [4.2 to 5.9] mmol l(-1). In the diabetes stratum these values were 6.6 [6.0 to 8.3]; (n=22), 6.1 [5.5 to 10.4]; (n=22) and 6.7 [5.6 to 8.3]; (n=19) mmol l(-1). The median [IQR] maximum peri-operative blood glucose values in the nondiabetes stratum were 6.0 [5.3 to 6.8], 6.3 [5.5 to 7.3] and 6.3 [5.8 to 7.4] mmol l(-1) in the control, dexamethasone 4 mg and dexamethasone 8 mg arms, respectively. In the diabetes stratum these values were 10.3 [8.1 to 12.4], 12.6 [10.3 to 18.3] and 13.6 [11.2 to 20.1] mmol l(-1). There was a significant interaction between pre-operative HbA1c value and 8 mg dexamethasone: every 1% increment in HbA1c produced a 4.0 mmol l(-1) elevation in maximal peri-operative glucose concentration. CONCLUSION Dexamethasone 4 mg or 8 mg did not induce greater hyperglycaemia compared with placebo for nondiabetic and well controlled diabetic patients. Maximal peri-operative blood glucose concentrations in patients with diabetes were related to baseline HbA1c values in a concentration-dependent fashion after 8 mg of dexamethasone.