What is the best approach for managing a patient with Diabetic Ketoacidosis (DKA)?

Management of Diabetic Ketoacidosis (DKA)

Begin immediate fluid resuscitation with isotonic saline at 15-20 mL/kg/hour for the first hour, followed by continuous IV regular insulin at 0.1 units/kg/hour (after confirming potassium ≥3.3 mEq/L), with aggressive potassium replacement and transition to subcutaneous basal insulin 2-4 hours before stopping the IV infusion to prevent rebound ketoacidosis. 1, 2

Initial Assessment and Diagnostic Workup

• Obtain plasma glucose, electrolytes with calculated anion gap, serum ketones (preferably β-hydroxybutyrate), blood urea nitrogen/creatinine, arterial or venous blood gas, complete blood count, urinalysis with urine ketones, and electrocardiogram 1, 2
• Diagnostic criteria require: blood glucose >250 mg/dL, arterial pH <7.3, serum bicarbonate <15 mEq/L, and presence of ketonemia or ketonuria 2
• Obtain bacterial cultures (blood, urine, throat) and chest X-ray if infection is suspected, as infection is a leading precipitating cause 1, 2
• Identify other precipitating factors including myocardial infarction, stroke, pancreatitis, insulin omission, or SGLT2 inhibitor use 2

Fluid Resuscitation Protocol

• Start with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour (approximately 1-1.5 L in average adults) during the first hour to restore intravascular volume and tissue perfusion 1, 2
• After initial resuscitation, adjust fluid rate based on hydration status, electrolyte levels, and urine output 2
• When serum glucose reaches 200-250 mg/dL, switch to 5% dextrose with 0.45-0.75% saline while continuing insulin infusion to prevent hypoglycemia and ensure complete resolution of ketoacidosis 2
• Total fluid replacement should approximate 1.5 times the 24-hour maintenance requirements 1

Critical Potassium Management

Do not start insulin if serum potassium is <3.3 mEq/L—this is an absolute contraindication that can cause life-threatening cardiac arrhythmias and death. 1, 2

• If K+ <3.3 mEq/L: Hold insulin therapy and aggressively replace potassium with 20-40 mEq/L in IV fluids until levels reach ≥3.3 mEq/L 1, 2
• If K+ 3.3-5.5 mEq/L: Add 20-30 mEq potassium per liter of IV fluid (use 2/3 KCl or potassium-acetate and 1/3 KPO₄) once adequate urine output is confirmed 1, 2
• If K+ >5.5 mEq/L: Withhold potassium initially but monitor closely every 2-4 hours, as insulin therapy will rapidly drive potassium intracellularly 2
• Target serum potassium of 4-5 mEq/L throughout treatment, as total body potassium depletion averages 3-5 mEq/kg body weight despite initial serum levels 2

Insulin Therapy Protocol

For Moderate-to-Severe DKA or Critically Ill Patients

• Administer IV bolus of 0.1 units/kg regular insulin, followed by continuous infusion at 0.1 units/kg/hour 1, 2
• Target glucose decline of 50-75 mg/dL per hour 1, 2
• If glucose does not fall by 50 mg/dL in the first hour, verify adequate hydration status, then double the insulin infusion rate every hour until achieving steady decline 2
• Continue insulin infusion until complete resolution of DKA (pH >7.3, bicarbonate ≥18 mEq/L, anion gap ≤12 mEq/L, glucose <200 mg/dL) regardless of glucose levels 1, 2
• When glucose reaches 200-250 mg/dL, add dextrose to IV fluids while maintaining insulin infusion to clear ketones 2

Alternative Approach for Mild-to-Moderate Uncomplicated DKA

• For hemodynamically stable, alert patients with mild-moderate DKA, subcutaneous rapid-acting insulin analogs at 0.15 units/kg every 2-3 hours combined with aggressive fluid management are equally effective, safer, and more cost-effective than IV insulin 3, 1, 2
• This approach requires adequate fluid replacement, frequent point-of-care glucose monitoring every 2-4 hours, treatment of concurrent infections, and appropriate follow-up 1, 2

Monitoring During Treatment

• Check blood glucose every 2-4 hours throughout treatment 1, 2
• Measure serum electrolytes, glucose, blood urea nitrogen, creatinine, osmolality, and venous pH every 2-4 hours 1, 2
• Direct measurement of β-hydroxybutyrate in blood is the preferred method for monitoring ketone clearance, as nitroprusside methods only detect acetoacetate and acetone 2
• Monitor for signs of cerebral edema (altered mental status, headache, neurological deterioration), particularly in younger patients, as this is a dire complication of DKA 2

Bicarbonate Administration

Bicarbonate is NOT recommended for DKA patients with pH >6.9-7.0, as multiple studies show no difference in resolution of acidosis or time to discharge, and it may worsen ketosis, cause hypokalemia, and increase cerebral edema risk. 3, 1, 2

• Consider bicarbonate only if pH <6.9 or when pH <7.2 pre-intubation to prevent hemodynamic collapse from apnea during intubation 4

Transition to Subcutaneous Insulin

This is the most critical step where errors commonly occur—administer basal insulin (glargine or detemir) 2-4 hours BEFORE stopping the IV insulin infusion to prevent recurrence of ketoacidosis and rebound hyperglycemia. 3, 1, 2

Resolution Criteria (All Must Be Met)

• Glucose <200 mg/dL 1, 2
• Serum bicarbonate ≥18 mEq/L 1, 2
• Venous pH >7.3 1, 2
• Anion gap ≤12 mEq/L 1, 2
• Patient able to tolerate oral intake 1, 2

Transition Protocol

• Administer long-acting basal insulin (glargine or detemir) subcutaneously 2-4 hours before discontinuing IV insulin 3, 1, 2
• Continue IV insulin for 1-2 hours after subcutaneous insulin administration to allow for absorption 1, 2
• Start multiple-dose regimen with combination of short/rapid-acting and intermediate/long-acting insulin once patient can eat 1, 2
• Recent evidence suggests adding low-dose basal insulin analog during IV insulin infusion may prevent rebound hyperglycemia without increasing hypoglycemia risk 3, 2

Special Considerations

SGLT2 Inhibitors

• Discontinue SGLT2 inhibitors immediately and do not restart until 3-4 days after metabolic stability is achieved, as these medications can precipitate euglycemic DKA 3, 2

Euglycemic DKA

• Requires same aggressive fluid management and continuous IV insulin despite lower glucose levels 5
• Add dextrose to IV fluids earlier to prevent hypoglycemia while continuing insulin to clear ketones 5
• Monitor β-hydroxybutyrate directly rather than relying on glucose levels alone 5

Common Pitfalls to Avoid

• Stopping IV insulin without prior basal insulin administration—this is the most common error leading to DKA recurrence 1, 2
• Starting insulin before confirming potassium ≥3.3 mEq/L, which can cause fatal arrhythmias 1, 2
• Premature termination of insulin therapy before complete resolution of ketoacidosis (all four criteria must be met) 2
• Failing to add dextrose when glucose falls below 200-250 mg/dL while continuing insulin therapy 2
• Inadequate potassium monitoring and replacement during treatment 2
• Using bicarbonate routinely for pH >6.9-7.0 3, 1, 2

Discharge Planning

• Identify outpatient diabetes care providers and schedule follow-up appointments before discharge 2
• Provide education on insulin administration, glucose monitoring, recognition and treatment of hyperglycemia/hypoglycemia, and sick day management 1, 2
• Educate on recognition, prevention, and management of DKA to prevent recurrence and readmission 3, 2
• Ensure appropriate insulin regimen is prescribed with attention to medication access and affordability 3