Clinicians have been reminded again of the risk of adverse metabolic outcomes in patients with diabetes whose SGLT2 inhibitors are not withheld in the 48 hours before surgery.
An Australian case series of 23 patients, published in the British Journal of Anaesthesia, found 20 patients (87%) developed ketosis – 13 without acidosis (57%) and 7 (30%) with either mild or moderate DKA.
The surgeries included emergency and elective procedures such as coronary artery bypass graft (CABG), laminectomy, laparoscopic bowel resections and amputations.
The study found two patients recognised before CABG surgery as having received a SGLT2 inhibitor, and therefore at risk for DKA, were managed expectantly with i.v. insulin and glucose, and did not develop ketosis. A third patient undergoing laparoscopic cholecystectomy did not develop perioperative ketosis.
None of the five patients recognised with ketosis before surgery who received i.v. insulin and glucose infusions early (before or during surgery) developed DKA.
The study, conducted at the Royal Melbourne Hospital, said patients who experienced ketosis without acidosis likely represent cases where earlier detection and intervention prevented progression to DKA.
It also found risk factors for protracted ketoacidosis included delayed perioperative recognition of SGLT2i use, administration of SGLT2i close to surgery, inadvertent preoperative administration of higher-than-recommended SGLT2i doses, prolonged fasting, and high-risk surgery such as cardiac surgery.
“Raising awareness for all clinicians involved in perioperative care regarding risk factors for SGLT2i-associated DKA is important, as risk mitigation strategies can prevent or minimise severity of DKA.”
“These include minimising ongoing SGLT2i exposure, minimising fasting, regular 2-4 hourly blood ketone monitoring, and early intervention with i.v. insulin and glucose. Early involvement of diabetes specialists to assist with management is recommended,” it said.
The authors also recommended risk-benefit analyses regarding deferment of elective surgery in some patients who have not withheld SGLT2 inhibitors.
“Although further research is required to determine optimal therapeutic strategies, our experience suggests that early recognition of SGLT2i use, early detection of ketosis, and early initiation of i.v. insulin and glucose are likely to minimise the risk of perioperative DKA,” the study concluded.
The ADS guidance on peri-procedural DKA with SGLT2 inhibitor use also notes that patients undergoing emergency surgery should be subsequently admitted to a ward capable of managing DKA in collaboration with endocrinology and critical care.