Emergency Management of Severe Metabolic Crisis in Type 1 Diabetes
Immediate Life-Threatening Priorities (First 30 Minutes)
This patient presents with diabetic ketoacidosis (DKA), severe hypokalemia, profound metabolic acidosis, and hypoglycemia—a constellation requiring simultaneous correction to prevent cardiac arrest and cerebral edema.
1. Airway and Hemodynamic Stabilization
- Secure airway if Glasgow Coma Scale <8 or unable to protect airway; provide supplemental oxygen to maintain saturation ≥94% 1.
- Establish two large-bore IV lines for simultaneous fluid resuscitation and electrolyte replacement 2, 3.
- Place on continuous cardiac monitoring given severe hypokalemia (K⁺ 2.7 mEq/L) which predisposes to fatal arrhythmias 4.
2. Correct Life-Threatening Hypoglycemia FIRST
- Administer 25 grams IV dextrose (50 mL of D50W) immediately for glucose 50 mg/dL to prevent seizures and neurologic injury 1.
- Recheck glucose in 15 minutes; repeat 15 g dextrose if <70 mg/dL 1.
- Do NOT start insulin until glucose >200 mg/dL and potassium >3.3 mEq/L to avoid precipitating cardiac arrest 4, 2.
3. Aggressive Potassium Repletion (Critical—Delays Insulin)
- Withhold insulin completely until serum potassium ≥3.3 mEq/L because insulin drives potassium intracellularly and can cause fatal arrhythmias 4, 2, 3.
- Start 40 mEq/hour IV potassium chloride (maximum safe peripheral rate) via central line if available; peripheral administration requires dilution to ≤10 mEq/100 mL 4.
- Recheck potassium every 1–2 hours initially; expect to administer 400–800 mEq in first 24 hours given profound total-body depletion 4.
- Once K⁺ reaches 3.3–5.0 mEq/L, reduce to 20–30 mEq/hour and continue aggressive replacement 2, 3.
Fluid Resuscitation (Simultaneous with Potassium)
Initial Bolus
- Administer 1–2 liters 0.9% normal saline over first hour to restore circulating volume and improve tissue perfusion 2, 3.
- Reassess hemodynamics; if hypotensive (BP 195/102 suggests hypertensive emergency, not shock), reduce rate to 250–500 mL/hour 2, 3.
Maintenance Fluids
- After initial bolus, switch to 0.45% saline at 250–500 mL/hour to replace free water deficit while avoiding rapid osmolality shifts 2, 3.
- When glucose falls to 200–250 mg/dL, add 5% dextrose to IV fluids (D5-0.45% saline) to prevent hypoglycemia while continuing insulin for ketoacidosis resolution 2, 3.
- Target total fluid replacement of 4–6 liters over first 12–24 hours depending on degree of dehydration 2, 3.
Insulin Therapy (Only After K⁺ ≥3.3 mEq/L and Glucose >200 mg/dL)
Initiation
- Start continuous IV regular insulin at 0.1 units/kg/hour (approximately 5–7 units/hour for 70 kg adult) 2, 3.
- Do NOT give IV bolus in this patient given initial hypoglycemia and severe hypokalemia 2, 3.
Titration
- Target glucose decline of 50–75 mg/dL per hour; if glucose not falling adequately, increase insulin infusion by 1 unit/hour every hour 2, 3.
- Once glucose reaches 200–250 mg/dL, reduce insulin to 0.05 units/kg/hour and add dextrose to IV fluids 2, 3.
- Continue insulin infusion until anion gap closes (<12 mEq/L) and bicarbonate >15 mEq/L, not just until glucose normalizes 2, 3.
Bicarbonate Therapy (Controversial—Use Cautiously)
Indications
- Consider sodium bicarbonate only if pH <6.9 to prevent cardiovascular collapse 1, 5, 2.
- Administer 100 mEq sodium bicarbonate in 400 mL sterile water over 2 hours if pH <6.9 5, 2.
- Avoid bicarbonate if pH ≥6.9 because it increases risk of hypokalemia, paradoxical CNS acidosis, and cerebral edema 1, 2.
Monitoring
- Recheck arterial blood gas 2 hours after bicarbonate; repeat dose if pH remains <6.9 5, 2.
- Increase potassium replacement by 10–20 mEq/hour during bicarbonate therapy because alkalinization drives potassium into cells 5, 2.
Metabolic Acidosis Management
Anion Gap Calculation
- Anion gap = Na⁺ – (Cl⁻ + HCO₃⁻) = 195 – (unknown Cl⁻ + 10) 2, 3.
- Elevated anion gap confirms ketoacidosis; check serum/urine ketones (β-hydroxybutyrate preferred) 2, 3.
Resolution Criteria
- DKA resolved when: glucose <200 mg/dL, bicarbonate ≥15 mEq/L, pH >7.3, and anion gap <12 mEq/L 2, 3.
- Typically requires 12–24 hours of continuous insulin infusion 2, 3.
Hypertensive Emergency Management
Blood Pressure Control
- Do NOT aggressively lower BP initially because cerebral perfusion may be impaired by severe acidosis and hyperosmolality 1.
- If systolic BP remains >220 mmHg or diastolic >120 mmHg after fluid resuscitation, use short-acting IV agents (labetalol 10–20 mg IV bolus or nicardipine 5 mg/hour infusion) 1.
- Avoid rapid BP reduction >25% in first hour to prevent cerebral ischemia 1.
Hyperammonemia Evaluation
Significance
- Ammonia 34 µmol/L is mildly elevated (normal <35 µmol/L) and likely reflects hepatic stress from DKA 2.
- Check liver function tests (AST, ALT, bilirubin) to exclude acute hepatic injury 2.
- Ammonia typically normalizes with DKA resolution; no specific therapy needed unless >100 µmol/L 2.
Monitoring Protocol
Hourly
Every 2 Hours
- Serum potassium, sodium, chloride, bicarbonate, anion gap 2, 3.
- Arterial or venous blood gas if pH <7.0 initially 2, 3.
Every 4 Hours
Transition to Subcutaneous Insulin
Timing
Protocol
- Give subcutaneous basal insulin (glargine 0.25 units/kg) 2–4 hours before stopping IV insulin to prevent rebound ketoacidosis 2, 3.
- Start rapid-acting insulin 0.1 units/kg before meals 2, 3.
- Continue IV insulin for 1–2 hours after first subcutaneous dose to ensure overlap 2, 3.
Critical Pitfalls to Avoid
- Never start insulin before correcting hypokalemia (K⁺ <3.3 mEq/L)—this causes cardiac arrest 4, 2.
- Never stop insulin when glucose normalizes—continue until anion gap closes to prevent rebound ketoacidosis 2, 3.
- Never give bicarbonate if pH ≥6.9—increases cerebral edema risk 1, 2.
- Never correct hyperglycemia faster than 75 mg/dL per hour—precipitates cerebral edema 2, 3.
- Never use metformin in DKA—causes lactic acidosis in setting of tissue hypoperfusion 6.