How to manage a patient with diabetes ketoacidosis?

Management of Diabetic Ketoacidosis

Begin immediate treatment 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 once potassium is ≥3.3 mEq/L, and aggressively replace potassium to maintain levels between 4-5 mEq/L throughout treatment. 1, 2

Initial Assessment and Diagnosis

Diagnostic Criteria:

• Blood glucose >250 mg/dL 1
• Arterial pH <7.3 1
• Serum bicarbonate <15-18 mEq/L 1, 2
• Presence of ketonemia or ketonuria 1

Essential Laboratory Workup:

• Plasma glucose, blood urea nitrogen/creatinine, serum ketones, electrolytes with calculated anion gap, osmolality 1, 2
• Arterial or venous blood gases, complete blood count with differential, electrocardiogram 1, 2
• Urinalysis and urine ketones 1, 2
• Obtain bacterial cultures (urine, blood, throat) if infection is suspected 1, 2

Identify Precipitating Factors:

• Infection (most common), myocardial infarction, stroke, pancreatitis, trauma 1
• Insulin discontinuation or inadequacy 1
• SGLT2 inhibitor use (can cause euglycemic DKA) 1
• Alcohol abuse, cerebrovascular accident, drugs 1

Fluid Resuscitation Protocol

First Hour:

• Isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour (approximately 1-1.5 L in average adult) 1, 2, 3
• This restores intravascular volume and renal perfusion 2, 3

Subsequent Fluid Management:

• Adjust based on hydration status, serum electrolyte levels, and urine output 1, 2
• Total fluid replacement should approximate 1.5 times the 24-hour maintenance requirements 2, 3
• When serum glucose reaches 250 mg/dL, switch to 5% dextrose with 0.45-0.75% NaCl 1, 2
• This prevents hypoglycemia while continuing insulin therapy to clear ketosis 1, 2

Insulin Therapy

Standard Protocol for Moderate-to-Severe DKA:

• Continuous IV regular insulin infusion at 0.1 units/kg/hour without initial bolus 1, 2, 3
• 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, then double the insulin infusion rate hourly until steady decline achieved 1, 2

Critical Point - Do Not Stop Insulin When Glucose Normalizes:

• When glucose reaches 250 mg/dL, decrease insulin to 0.05-0.1 units/kg/hour and add dextrose to IV fluids 2
• Continue insulin infusion until complete resolution of ketoacidosis regardless of glucose levels 1, 2
• Interruption of insulin when glucose falls is a common cause of persistent or worsening ketoacidosis 1

Alternative for Mild-to-Moderate Uncomplicated DKA:

• For hemodynamically stable, alert patients: subcutaneous rapid-acting insulin analogs at 0.15 units/kg every 2-3 hours combined with aggressive fluid management 1
• This approach is equally effective, safer, and more cost-effective than IV insulin 1
• Continuous IV insulin remains standard for critically ill and mentally obtunded patients 1, 3

Potassium Management - Critical for Preventing Mortality

This is a high-risk area requiring meticulous attention:

Before Starting Insulin:

• If K+ <3.3 mEq/L: DO NOT start insulin 1, 3
• Aggressively replace potassium first to prevent life-threatening cardiac arrhythmias and respiratory muscle weakness 1, 3
• Total body potassium depletion averages 3-5 mEq/kg body weight despite initial serum levels 1

During Treatment:

• If K+ 3.3-5.5 mEq/L: Add 20-30 mEq potassium per liter of IV fluid (use 2/3 KCl and 1/3 KPO₄) once adequate urine output confirmed 1, 2, 3
• If K+ >5.5 mEq/L: Withhold potassium initially but monitor closely, as levels will drop rapidly with insulin therapy 1, 3
• Target serum potassium of 4-5 mEq/L throughout treatment 1, 2, 3
• Insulin therapy will unmask total body potassium depletion by driving potassium intracellularly 1

Bicarbonate Administration - Generally NOT Recommended

The American Diabetes Association does NOT recommend bicarbonate for pH >6.9-7.0 1, 2

Rationale:

• Multiple studies show no difference in resolution of acidosis or time to discharge 1, 2
• May worsen ketosis, cause hypokalemia, and increase cerebral edema risk 1, 2
• Consider only if pH <6.9 or in peri-intubation period to prevent hemodynamic collapse 4

Monitoring Protocol

Frequent Monitoring is Essential:

• Blood glucose every 1-2 hours 2
• Serum electrolytes, glucose, BUN, creatinine, osmolality, and venous pH every 2-4 hours 1, 2, 3
• Potassium levels every 2-4 hours during active treatment 1
• Follow venous pH (typically 0.03 units lower than arterial pH) and anion gap to monitor acidosis resolution 1, 2

Preferred Ketone Monitoring:

• Direct measurement of β-hydroxybutyrate in blood is preferred 1, 2
• Nitroprusside method is misleading as it only measures acetoacetic acid and acetone, not β-hydroxybutyrate 1, 2

Resolution Criteria

DKA is resolved when ALL of the following are met:

• Glucose <200 mg/dL 1, 2, 3
• Serum bicarbonate ≥18 mEq/L 1, 2, 3
• Venous pH >7.3 1, 2, 3
• Anion gap ≤12 mEq/L 1, 2, 3

Target glucose between 150-200 mg/dL until these resolution parameters are met 1

Transition to Subcutaneous Insulin - Critical Timing

Administer basal insulin (glargine, detemir, or NPH) 2-4 hours BEFORE stopping IV insulin infusion 1, 2, 3

This prevents:

• Recurrence of ketoacidosis 1, 2, 3
• Rebound hyperglycemia 1, 2, 3

If Patient Can Eat:

• Start multiple-dose schedule using combination of short/rapid-acting and intermediate/long-acting insulin 1
• Initial dose approximately 0.5-1.0 units/kg/day for newly diagnosed patients 1

If Patient Remains NPO (intubated):

• Continue IV insulin and fluid replacement, supplement with subcutaneous regular insulin as needed 1, 3

Recent Evidence:

• Adding low-dose basal insulin analog during IV insulin infusion may prevent rebound hyperglycemia without increasing hypoglycemia risk 1

Special Considerations for Critically Ill/Intubated Patients

Continuous IV regular insulin at 0.1 units/kg/hour is the standard of care for:

• Critically ill patients 1, 3
• Mentally obtunded patients 1, 3
• Moderate-to-severe DKA 1, 3

Airway Management:

• BiPAP is not recommended due to aspiration risk 4
• If intubation required, consider IV sodium bicarbonate peri-intubation if pH <7.2 to prevent hemodynamic collapse from apnea 4

Common Pitfalls to Avoid

These errors lead to treatment failure and complications:

1. Premature termination of insulin therapy before complete resolution of ketosis 1, 2
2. Stopping IV insulin without prior administration of basal subcutaneous insulin - causes rebound hyperglycemia and ketoacidosis 1
3. Interruption of insulin infusion when glucose levels fall without adding dextrose - common cause of persistent or worsening ketoacidosis 1, 2
4. Inadequate potassium monitoring and replacement - leading cause of mortality in DKA 1, 2
5. Starting insulin when K+ <3.3 mEq/L - can cause life-threatening arrhythmias 1, 3
6. Overly rapid correction of osmolality - increases risk of cerebral edema, particularly in children 1, 4
7. Using bicarbonate in patients with pH >6.9-7.0 - worsens outcomes 1, 2

Cerebral Edema Prevention

Monitor closely for signs of cerebral edema:

• More common in children and adolescents than adults 1
• Watch for altered mental status, headache, or neurological deterioration 1
• Use gradual correction of glucose and osmolality to minimize risk 2, 4

SGLT2 Inhibitor Considerations

If patient is on SGLT2 inhibitors:

• Discontinue immediately 1
• Do not restart until 3-4 days after metabolic stability achieved 1
• Must be discontinued 3-4 days before any planned surgery to prevent euglycemic DKA 1

Discharge Planning

Before discharge, ensure:

• Identification of outpatient diabetes care providers 1
• Patient education on glucose monitoring, insulin administration, recognition and treatment of hyperglycemia/hypoglycemia 1
• Appropriate insulin regimen prescribed with attention to medication access and affordability 1
• Education on recognition, prevention, and management of DKA to prevent recurrence 1
• Follow-up appointments scheduled prior to discharge 1