What is the management of Diabetic Ketoacidosis (DKA)?

Management of Diabetic Ketoacidosis (DKA)

Begin immediate fluid resuscitation with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour for the first hour, followed by continuous IV regular insulin at 0.1 units/kg/hour once potassium is ≥3.3 mEq/L, and continue insulin until complete resolution of ketoacidosis (pH >7.3, bicarbonate ≥18 mEq/L, anion gap ≤12 mEq/L) regardless of glucose levels. 1, 2

Initial Assessment and Diagnosis

Diagnostic Criteria

• DKA is diagnosed by: blood glucose >250 mg/dL, arterial pH <7.3, serum bicarbonate <15 mEq/L, and positive serum/urine ketones. 3, 1
• Note that hyperglycemia has been de-emphasized in recent guidelines due to increasing incidence of euglycemic DKA, particularly with SGLT2 inhibitor use. 4

Laboratory Evaluation

• Obtain immediately: plasma glucose, blood urea nitrogen/creatinine, serum ketones, electrolytes with calculated anion gap, osmolality, urinalysis, urine ketones, arterial blood gases, complete blood count with differential, and electrocardiogram. 3, 1, 2
• Direct measurement of β-hydroxybutyrate in blood is the preferred method for ketone monitoring, as the nitroprusside method only measures acetoacetic acid and acetone. 1, 2
• Obtain bacterial cultures (urine, blood, throat) if infection is suspected and administer appropriate antibiotics. 3, 1, 2

Identify Precipitating Factors

• Look specifically for: infection, myocardial infarction, stroke, pancreatitis, trauma, insulin omission/inadequacy, SGLT2 inhibitor use, alcohol abuse, or cerebrovascular accident. 3, 1

Fluid Resuscitation

Initial Fluid Therapy

• Start with isotonic saline (0.9% NaCl) at 15-20 mL/kg body weight/hour (approximately 1-1.5 L in average adult) during the first hour to restore intravascular volume and renal perfusion. 3, 1, 2
• This aggressive initial fluid replacement is critical for restoring tissue perfusion and improving insulin sensitivity. 1

Subsequent Fluid Management

• After the first hour, choose fluids based on corrected serum sodium (add 1.6 mEq to sodium value for each 100 mg/dL glucose above 100 mg/dL), hydration status, and urine output. 3
• Use 0.45% NaCl at 4-14 mL/kg/hour if corrected serum sodium is normal or elevated; use 0.9% NaCl at similar rate if corrected serum sodium is low. 3
• When serum glucose reaches 250 mg/dL, change fluid to 5% dextrose with 0.45-0.75% NaCl to prevent hypoglycemia while continuing insulin therapy to clear ketosis. 1, 2

Insulin Therapy

Critical Pre-Insulin Check

• DO NOT start insulin if serum potassium is <3.3 mEq/L—this is an absolute contraindication. 1, 5
• Delay insulin therapy and aggressively replace potassium until levels reach ≥3.3 mEq/L to prevent life-threatening cardiac arrhythmias and respiratory muscle weakness. 1, 5

Insulin Initiation

• For moderate to severe DKA or critically ill/mentally obtunded patients: start continuous IV regular insulin infusion at 0.1 units/kg/hour without an initial bolus. 1, 2, 5
• For mild-to-moderate uncomplicated DKA: subcutaneous rapid-acting insulin analogs combined with aggressive fluid management are equally effective, safer, and more cost-effective than IV insulin. 1, 2

Insulin Adjustment

• If plasma glucose does not fall by 50 mg/dL in the first hour, verify adequate hydration, then double the insulin infusion rate hourly until achieving steady glucose decline of 50-75 mg/hour. 1, 2
• When serum glucose reaches 250 mg/dL, decrease insulin infusion to 0.05-0.1 units/kg/hour and add dextrose to IV fluids. 2, 5
• Continue insulin infusion until COMPLETE resolution of ketoacidosis regardless of glucose levels—this is critical to prevent recurrence. 1, 2

Electrolyte Management

Potassium Replacement

• If K+ <3.3 mEq/L: Hold insulin, aggressively replace potassium until ≥3.3 mEq/L. 1, 5
• If K+ 3.3-5.5 mEq/L: Add 20-30 mEq/L potassium to IV fluids (use 2/3 KCl and 1/3 KPO₄) once adequate urine output is confirmed. 1, 2
• If K+ >5.5 mEq/L: Withhold potassium initially but monitor closely, as levels will drop rapidly with insulin therapy. 1
• Target serum potassium of 4-5 mEq/L throughout treatment. 1, 2
• Despite presenting with hyperkalemia, total body potassium depletion is universal in DKA, and insulin therapy will further lower serum potassium. 1

Phosphate Replacement

• Routine phosphate replacement has not shown clinical benefit. 2
• Consider careful phosphate replacement only in patients with cardiac dysfunction, anemia, respiratory depression, or serum phosphate <1.0 mg/dL. 2

Bicarbonate Administration

• Bicarbonate is NOT recommended for DKA patients with pH >6.9-7.0, as studies show no difference in resolution of acidosis or time to discharge, and it may worsen ketosis, cause hypokalemia, and increase cerebral edema risk. 1, 2, 6
• Consider IV sodium bicarbonate only if serum pH falls below 6.9, or when pH <7.2 and/or bicarbonate <10 mEq/L pre- and post-intubation to prevent hemodynamic collapse. 6

Monitoring During Treatment

Frequency of Monitoring

• Check blood glucose every 1-2 hours. 2
• Draw blood every 2-4 hours for serum electrolytes, glucose, blood urea nitrogen, creatinine, osmolality, and venous pH. 1, 2
• Follow venous pH (typically 0.03 units lower than arterial pH) and anion gap to monitor resolution of acidosis. 1, 2

Resolution Criteria

• DKA is resolved when ALL of the following are met: glucose <200 mg/dL, serum bicarbonate ≥18 mEq/L, venous pH >7.3, and anion gap ≤12 mEq/L. 1, 2
• Target glucose between 150-200 mg/dL until DKA resolution parameters are met. 1

Transition to Subcutaneous Insulin

Critical Timing

• Administer basal insulin (intermediate or long-acting such as glargine or detemir) 2-4 hours BEFORE stopping IV insulin infusion to prevent recurrence of ketoacidosis and rebound hyperglycemia. 1, 2, 5
• This overlap period is essential—stopping IV insulin without prior basal insulin administration is the most common error leading to DKA recurrence. 5

Insulin Regimen

• Once the patient can eat, start a multiple-dose schedule using a combination of short/rapid-acting and intermediate/long-acting insulin. 1, 2, 5
• If the patient remains NPO after DKA resolution, continue IV insulin and fluid replacement, supplementing with subcutaneous regular insulin as needed. 1

Special Considerations and Pitfalls

Common Errors to Avoid

• Premature termination of insulin therapy before complete resolution of ketosis leads to DKA recurrence. 1, 2
• Interruption of insulin infusion when glucose levels fall without adding dextrose causes persistent or worsening ketoacidosis. 1, 2
• Inadequate monitoring and replacement of potassium is a leading cause of mortality in DKA. 1
• Overly rapid correction of osmolality increases risk of cerebral edema, particularly in children. 1, 6

SGLT2 Inhibitors

• Discontinue SGLT2 inhibitors 3-4 days before any planned surgery to prevent euglycemic DKA. 1

Airway Management in Critically Ill Patients

• For impending respiratory failure, BiPAP is not recommended due to aspiration risks. 6
• Use intubation and mechanical ventilation with monitoring and management of acid-base and fluid status. 6

Cerebral Edema Prevention

• Use gradual correction of glucose and osmolality to minimize risk of cerebral edema. 2
• Be particularly vigilant in children and adolescents, who are at higher risk. 7

Discharge Planning

• Structured discharge planning should include: identification of outpatient diabetes care providers, understanding of diabetes diagnosis, glucose monitoring, home glucose goals, and when to call healthcare professional. 1, 5
• Patient education on insulin administration, sick day management, and recognition of early DKA symptoms is essential for prevention. 1, 4