What is the best course of action for a patient with diabetic ketoacidosis and appendicitis who has been NPO for approximately 20 hours before a scheduled surgery?

Management of DKA Patient with Appendicitis After 20 Hours NPO Before Surgery

For a patient with diabetic ketoacidosis and appendicitis who has been NPO for 20 hours, proceed immediately to emergency surgery while simultaneously initiating continuous intravenous insulin infusion and aggressive fluid resuscitation—do not delay surgery to fully resolve the DKA, as appendicitis is a surgical emergency and delaying increases mortality risk from perforation and sepsis. 1

Immediate Preoperative Actions

Start continuous IV insulin infusion immediately upon diagnosis of DKA, even as you prepare the patient for emergency surgery. 1 The American Diabetes Association recommends this as standard of care for critically ill patients with DKA, and emergency surgery like appendicitis should proceed regardless of glucose control with implementation of intensive perioperative protocols. 1

Critical Metabolic Stabilization (Parallel to Surgical Preparation)

• Begin aggressive fluid resuscitation with isotonic saline to correct the severe dehydration from 20 hours NPO plus DKA-induced volume depletion. 2
• Initiate potassium supplementation in IV fluids (1/3 KPO4 and 2/3 KCl or K-acetate) as insulin therapy will drive potassium intracellularly, risking life-threatening hypokalemia during surgery. 2
• Check pH and consider bicarbonate only if pH is <7.0-7.1, and even then add it to IV fluids (50 mmol sodium bicarbonate in 200 ml sterile water at 200 ml/h) rather than as a bolus. 1, 2
• Do NOT wait for DKA resolution before proceeding to surgery—the surgical emergency takes precedence. 1

Intraoperative Management

Maintain continuous IV insulin infusion throughout the entire surgical procedure with hourly glucose monitoring and adjustments. 1

Glucose Targets and Monitoring

• Target blood glucose of 140-180 mg/dL (7.8-10.0 mmol/L) intraoperatively, though the broader range of 100-180 mg/dL is acceptable. 1
• Measure blood glucose hourly during the procedure, especially given the metabolic instability from DKA. 2, 1
• Continue IV insulin infusion without interruption—this is non-negotiable in a patient with active DKA undergoing surgery. 1

Fluid and Electrolyte Management

• Continue aggressive fluid replacement to address both the prolonged NPO status and DKA-induced dehydration. 2
• Monitor and replace potassium carefully as both insulin therapy and correction of acidosis will lower serum potassium. 2
• Avoid hypophosphatemia by including phosphate in potassium replacement, particularly important given the cardiac stress of surgery and anesthesia. 2

Postoperative Management

Do not discontinue IV insulin until 2-4 hours after administering basal subcutaneous insulin to prevent rebound hyperglycemia and recurrence of ketoacidosis. 1

Transition Strategy

• Implement a basal-bolus insulin regimen (basal insulin plus premeal rapid-acting insulin) rather than correction-only insulin, as this approach reduces perioperative complications. 1
• Resume oral feeding as soon as clinically appropriate to facilitate transition back to subcutaneous insulin and normalize metabolic status. 1
• Continue hourly glucose monitoring in the immediate postoperative period until metabolic stability is achieved. 1

DKA Resolution Criteria

• Confirm DKA resolution before transitioning fully to subcutaneous insulin: glucose <200 mg/dL, serum bicarbonate ≥18 mEq/L, and venous pH >7.3. 2
• Monitor venous pH and anion gap every 2-4 hours rather than repeating arterial blood gases (venous pH is typically 0.03 units lower than arterial). 2

Critical Pitfalls to Avoid

Never stop IV insulin before adequate subcutaneous insulin overlap—this is the most common cause of rebound ketoacidosis in the postoperative period. 1

Specific Warnings

• Do not assume postoperative drowsiness is solely from anesthesia—check for hypoglycemia immediately, as the patient has been on continuous insulin infusion. 3
• If the patient was on SGLT2 inhibitors (empagliflozin, dapagliflozin, canagliflozin), recognize that these can cause euglycemic DKA where glucose may be near-normal despite severe ketoacidosis. 1, 4, 5, 6, 7 SGLT2 inhibitors should have been discontinued 3-4 days before elective surgery, but in this emergency scenario, be vigilant for ongoing ketogenesis even with controlled glucose. 1, 8
• Beware of abdominal pain from DKA mimicking or masking appendicitis—the metabolic acidosis itself can cause severe abdominal pain that may confound the surgical diagnosis. 9 However, given 20 hours of symptoms and NPO status, proceed with surgery as planned while treating both conditions simultaneously.

Hemodynamic Considerations

• Maintain mean arterial pressure 60-70 mmHg (or >70 mmHg if patient is hypertensive) to ensure adequate renal perfusion during DKA treatment and surgery. 2
• Implement hemodynamic monitoring to guide fluid resuscitation and vasopressor use, as this patient faces dual risks from DKA-induced hypovolemia and surgical stress. 2