sglt2 inhibitors in postoperative period in cardiac surgery

Use of SGLT2 inhibitors postoperatively following cardiac surgery: SGLT2 inhibitors, including canagliflozin, dapagliflozin, and empagliflozin, have important multifaceted benefits in patients undergoing cardiac surgery, especially for managing heart failure and reducing cardiovascular and renal complications. Their mechanisms include glycemic control, improved myocardial energy metabolism through promoting ketone body utilization, hemodynamic effects via osmotic diuresis and natriuresis reducing cardiac preload and afterload, and anti-inflammatory as well as antifibrotic actions that mitigate surgical myocardial injury and remodeling Dong et al. 2026 Dong et al. 2026.

Emerging clinical evidence from observational studies and pilot trials suggests that preoperative and perioperative use of SGLT2 inhibitors is associated with reduced postoperative cardiovascular complications, myocardial injury, and heart failure events in cardiac surgery patients, including those with type 2 diabetes Dong et al. 2026 Dong et al. 2026. Moreover, SGLT2 inhibitors may reduce the incidence of cardiac surgery-associated acute kidney injury (CSA-AKI), possibly through enhanced tubuloglomerular feedback, decreased oxidative stress, and reduced inflammation Al Chalabi et al. 2025 Al Chalabi et al. 2025.

Safety concerns in the postoperative period: The principal safety concern with SGLT2 inhibitors in the perioperative setting, particularly post-cardiac surgery, is euglycemic diabetic ketoacidosis (euDKA), a metabolic emergency characterized by ketosis and acidosis but without significant hyperglycemia Deng et al. 2026 Deng et al. 2026. Cardiac surgery patients are at high risk due to prolonged fasting, surgical stress, cardiopulmonary bypass-induced inflammation, and volume depletion, which potentiate ketogenesis through mechanisms including increased arginine vasopressin-mediated glucagon secretion and altered renal ketone handling Deng et al. 2026 Deng et al. 2026.

Clinical reports describe increased postoperative ketone production and acid-base disturbance with canagliflozin, indicating heightened risk of euDKA especially in patients with preserved renal function or long-standing diabetes Dong et al. 2026 Dong et al. 2026. Infections such as urinary tract and genital mycotic infections may also be elevated with SGLT2 inhibitor use Dong et al. 2026 Dong et al. 2026; rare but serious events like necrotizing fasciitis of the perineum have been reported (SmPC Dapagliflozin) SmPC Dapagliflozin.

Perioperative management and recommendations: Based on the UK guidelines, surgical patients with type 2 diabetes benefit from optimized glycemic control and cardiovascular risk management, with SGLT2 inhibitors playing an important role in cardiovascular and renal protection (NICE NG28, NICE CKS) NICE NG28,NICE CKS. However, NICE NG180 recommends postoperative care in specialized settings for high-risk patients, emphasizing careful monitoring (NICE NG180) NICE NG180.

To mitigate euDKA risk, SGLT2 inhibitors are generally recommended to be withheld 3 to 4 days before major surgeries like cardiac procedures, with cautious postoperative reinitiation when the patient is hemodynamically stable, tolerating oral intake, and ketone-free Deng et al. 2026 Deng et al. 2026. During the perioperative period, aggressive but balanced hydration is crucial to suppress vasopressin-driven ketogenesis and minimize volume depletion, while avoiding volume overload, especially in heart failure patients Deng et al. 2026 Deng et al. 2026.

Monitoring should prioritize blood (capillary) ketone testing over urine ketones due to potential renal reabsorption of ketones masking ketosis Deng et al. 2026 Deng et al. 2026. Any signs of nausea, vomiting, abdominal pain, or unexplained acidosis mandate urgent ketone assessment and discontinuation of SGLT2 inhibitors if DKA is suspected (SmPC Dapagliflozin) SmPC Dapagliflozin.

It is important to balance the risk of postoperative euDKA against the risk of heart failure decompensation due to interruption of cardioprotective SGLT2 inhibitors, especially as abrupt cessation can cause rebound fluid retention and increased hospitalization risk Deng et al. 2026 Deng et al. 2026. Recent clinical data suggest that in emergencies with limited withholding time, the DKA risk may be low, but in elective cardiac surgery with prolonged fasting and inflammatory stress, strict withholding and monitoring protocols remain advisable Deng et al. 2026 Deng et al. 2026.

Evidence from ongoing and recent trials emphasizes SGLT2 inhibitors' role in reducing cardiac surgery-associated complications including acute kidney injury, with dapagliflozin and empagliflozin showing promise without major safety concerns when appropriately managed Al Chalabi et al. 2025 Al Chalabi et al. 2025.

Summary: SGLT2 inhibitors have beneficial roles in the postoperative period following cardiac surgery, particularly in preventing heart failure progression and acute kidney injury. However, their use requires vigilant perioperative management due to the risk of euDKA and infections. Current expert consensus and UK guidelines recommend withholding these drugs 3–4 days before cardiac surgery, close monitoring of renal function and ketones perioperatively, and cautious, individualized reinitiation postoperatively. This approach balances the cardioprotective benefits against metabolic risks in this high-risk surgical population.