What is the immediate treatment for a patient presenting with diabetic ketoacidosis (DKA) in the emergency room (ER)?

Immediate Treatment of Diabetic Ketoacidosis in the Emergency Room

Begin with aggressive isotonic saline resuscitation at 15-20 mL/kg/hour (approximately 1-1.5 L in the first hour) to restore circulatory volume, followed by continuous IV regular insulin at 0.1 units/kg/hour once potassium is ≥3.3 mEq/L, while simultaneously identifying and treating precipitating factors such as infection or myocardial infarction. 1, 2

Initial Assessment and Diagnostic Workup

Upon presentation, immediately obtain:

• Plasma glucose, arterial or venous blood gases, complete metabolic panel with calculated anion gap, serum ketones (β-hydroxybutyrate preferred), osmolality, complete blood count, and electrocardiogram 3, 1
• Bacterial cultures (blood, urine, throat) if infection is suspected 1
• Search for precipitating factors requiring immediate intervention: sepsis, myocardial infarction, stroke, aspiration pneumonia, pancreatitis, medication noncompliance, or SGLT2 inhibitor use 3, 1, 4

The diagnostic criteria are: blood glucose >250 mg/dL, arterial pH <7.3, serum bicarbonate <15 mEq/L, and presence of ketonemia or ketonuria 1

Fluid Resuscitation Protocol

First Hour

Start with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour to restore intravascular volume and tissue perfusion 1, 2. Balanced electrolyte solutions may be considered as an alternative, with some evidence suggesting faster DKA resolution 2, 5.

Subsequent Fluid Management

• Adjust fluid rate based on hydration status, serum sodium, and urine output, with total fluid replacement approximating 1.5 times the 24-hour maintenance requirements 3
• 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 ketoacidosis resolution 1, 2
• Avoid inducing changes in serum osmolality exceeding 3 mOsm/kg/hour to prevent cerebral edema 2

Insulin Therapy

Critical Pre-Insulin Check

DO NOT start insulin if serum potassium is <3.3 mEq/L – aggressively replace potassium first to prevent life-threatening cardiac arrhythmias and respiratory muscle weakness 3, 1

Standard Insulin Protocol

Initiate continuous IV regular insulin infusion at 0.1 units/kg/hour without a bolus for moderate-to-severe DKA or critically ill/mentally obtunded patients 3, 1, 2

• If plasma glucose does not fall by 50 mg/dL in the first hour, check hydration status; if adequate, double the insulin infusion rate every hour until achieving a steady glucose decline of 50-75 mg/dL per hour 1, 2
• Continue insulin infusion until resolution of ketoacidosis (pH >7.3, bicarbonate ≥18 mEq/L, anion gap ≤12 mEq/L) regardless of glucose levels 1

Alternative for Mild-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 1, 6

Potassium Management

Critical Potassium Thresholds

• If K+ <3.3 mEq/L: DELAY insulin therapy and aggressively replace potassium until ≥3.3 mEq/L 3, 1
• If K+ 3.3-5.5 mEq/L: Add 20-30 mEq potassium per liter of IV fluid (2/3 KCl and 1/3 KPO₄) once adequate urine output is confirmed 3, 1, 2
• If K+ >5.5 mEq/L: Withhold potassium initially but monitor closely, as levels will drop rapidly with insulin therapy 3

Target serum potassium of 4-5 mEq/L throughout treatment 3, 1. Total body potassium depletion averages 3-5 mEq/kg body weight despite potentially normal or elevated initial levels due to acidosis 1, 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 1, 2, 5

Consider bicarbonate only if pH <6.9: administer 100 mmol sodium bicarbonate in 400 mL sterile water at 200 mL/hour 2

Monitoring Protocol

Draw blood every 2-4 hours for:

• Serum electrolytes, glucose, BUN, creatinine, osmolality, and venous pH 3, 1, 2
• β-hydroxybutyrate if available (preferred marker for ketoacidosis) 3, 1

Continuous cardiac monitoring is crucial to detect arrhythmias early, particularly given the risk of hypokalemia 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
• Anion gap ≤12 mEq/L 3, 1, 2

Common Pitfall to Avoid

DO NOT stop insulin when glucose normalizes – add dextrose to IV fluids and continue insulin until ketoacidosis resolves 3, 1. Premature termination of insulin therapy before complete resolution of ketosis is a leading cause of DKA recurrence 1.

Transition to Subcutaneous Insulin

Administer basal insulin (intermediate or long-acting) 2-4 hours BEFORE stopping IV insulin infusion to prevent recurrence of ketoacidosis and rebound hyperglycemia 3, 1, 2

Recent evidence suggests adding low-dose subcutaneous basal insulin analog (e.g., glargine) alongside IV insulin may prevent rebound hyperglycemia and shorten hospital stays 1, 2, 5

Special Considerations

Cerebral Edema Prevention

Monitor closely for altered mental status, headache, or neurological deterioration, particularly in children and adolescents who are at higher risk 1, 7. Higher BUN at presentation is a risk factor 2.

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 1, 2

Phosphate Replacement

Consider phosphate replacement only in patients with cardiac dysfunction, anemia, respiratory depression, or serum phosphate <1.0 mg/dL 2. Routine phosphate replacement has not shown beneficial effects on clinical outcomes 2.

Airway Management in Critically Ill Patients

For impending respiratory failure, avoid BiPAP due to aspiration risks; proceed with intubation and mechanical ventilation 5. Consider IV sodium bicarbonate pre- and post-intubation if pH <7.2 to prevent metabolic acidosis and hemodynamic collapse from apnea during intubation 5.