What is the recommended emergency department management for a patient presenting with a hyperglycemic crisis (diabetic ketoacidosis or hyperosmolar hyperglycemic state)?

Emergency Department Management of Hyperglycemic Crisis

Begin immediate aggressive fluid resuscitation with isotonic saline (0.9% NaCl) at 15–20 mL/kg/hour (approximately 1–1.5 L in the first hour) for all patients presenting with hyperglycemic crisis, whether diabetic ketoacidosis (DKA) or hyperosmolar hyperglycemic state (HHS), to restore intravascular volume and renal perfusion. 1

Initial Diagnostic Workup

Obtain the following laboratory studies immediately upon suspicion of hyperglycemic crisis:

• Plasma glucose to differentiate DKA (>250 mg/dL) from HHS (≥600 mg/dL) 1, 2
• Arterial or venous pH and serum bicarbonate – DKA shows pH <7.3 and bicarbonate <15 mEq/L, while HHS shows pH ≥7.3 and bicarbonate ≥15 mEq/L 1, 2
• Serum electrolytes with calculated anion gap to assess metabolic status 1, 2
• β-hydroxybutyrate measurement in blood (preferred over nitroprusside-based urine ketone tests, which miss the predominant ketone body and may delay appropriate therapy) 1
• Effective serum osmolality calculated as 2×[Na (mEq/L)] + glucose (mg/dL)/18 – HHS requires ≥320 mOsm/kg 1, 2
• BUN, creatinine, complete blood count, urinalysis, and electrocardiogram 1, 2
• Bacterial cultures (blood, urine, throat) if infection is suspected, as infection is the most common precipitating factor 1, 2

Fluid Management Protocol

First Hour

• Administer isotonic saline 0.9% at 15–20 mL/kg/hour (approximately 1–1.5 L in average adults) to restore intravascular volume 1
• The typical total body water deficit is 6–9 L in DKA and 9 L (100–220 mL/kg) in HHS 1

After First Hour

• Calculate corrected serum sodium by adding 1.6 mEq/L for each 100 mg/dL glucose elevation above 100 mg/dL 1, 2
• If corrected sodium is normal or elevated, switch to 0.45% NaCl at 4–14 mL/kg/hour 1
• If corrected sodium is low, continue 0.9% NaCl at 4–14 mL/kg/hour 1

When Glucose Declines

• For DKA: When glucose reaches ≈250 mg/dL, change IV fluids to 5% dextrose with 0.45–0.75% NaCl while maintaining insulin infusion 1
• For HHS: When glucose reaches ≈300 mg/dL, change to dextrose-containing fluids and reduce insulin to 0.05–0.1 units/kg/hour, maintaining glucose at 250–300 mg/dL until hyperosmolarity resolves 1, 2
• Critical pitfall: Limit osmolality change to ≤3 mOsm/kg/hour (maximum 3–8 mOsm/kg/hour) to prevent cerebral edema and central pontine myelinolysis 1, 2

Potassium Management – Critical Priority

Total body potassium depletion is universal in hyperglycemic crisis (3–5 mEq/kg in DKA, 4–6 mEq/kg in HHS), even when serum levels appear normal or elevated initially. 1

• If serum K⁺ <3.3 mEq/L: HOLD INSULIN and aggressively replace potassium at 20–40 mEq/hour until K⁺ ≥3.3 mEq/L to prevent life-threatening arrhythmias, cardiac arrest, and respiratory muscle weakness 1
• If K⁺ 3.3–5.5 mEq/L: Add 20–30 mEq potassium per liter of IV fluid (approximately 2/3 KCl + 1/3 KPO₄) once adequate urine output is confirmed 1
• If K⁺ >5.5 mEq/L: Withhold potassium initially but monitor every 2–4 hours, as levels will fall rapidly with insulin therapy 1
• Target serum potassium throughout treatment: 4–5 mEq/L 1

Insulin Therapy

For Moderate-to-Severe DKA or Critically Ill/Obtunded Patients

• Confirm serum potassium ≥3.3 mEq/L before initiating insulin 1
• Administer IV bolus of regular insulin 0.1–0.15 units/kg, followed by continuous infusion of 0.1 units/kg/hour 1
• Target glucose decline of 50–75 mg/dL per hour 1
• If glucose does not fall by ≥50 mg/dL in the first hour despite adequate hydration, double the insulin infusion rate each hour until steady decline is achieved 1

For Mild-to-Moderate Uncomplicated DKA (Hemodynamically Stable, Alert Patients)

• 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
• This approach requires adequate fluid replacement, frequent point-of-care glucose monitoring, and treatment of concurrent infections 1

Special Considerations for HHS

• Delay insulin initiation until glucose no longer falls with IV fluids alone, unless ketonemia is present 2
• Start with 0.1 units/kg bolus followed by 0.1 units/kg/hour infusion 2
• When glucose reaches 250–300 mg/dL, reduce insulin to 0.05–0.1 units/kg/hour and add dextrose to maintain glucose at 250–300 mg/dL until osmolality normalizes 2

Critical Insulin Management Principles

• Continue insulin infusion until complete DKA resolution (pH >7.3, bicarbonate ≥18 mEq/L, anion gap ≤12 mEq/L, glucose <200 mg/dL) regardless of glucose level 1
• For HHS: Continue until osmolality <300 mOsm/kg, hypovolemia corrected, and mental status returns to baseline 2
• Ketonemia resolves more slowly than hyperglycemia – do not stop insulin prematurely 1

Bicarbonate Administration – Generally NOT Recommended

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

• For pH <6.9, consider 100 mmol sodium bicarbonate in 400 mL sterile water, infused at 200 mL/hour 1
• Bicarbonate use is not recommended in HHS (pH typically ≥7.30) 2

Monitoring During Treatment

• Draw blood every 2–4 hours for serum electrolytes, glucose, BUN, creatinine, calculated osmolality, and venous pH 1
• Venous pH (typically 0.03 units lower than arterial pH) is adequate for monitoring; routine repeat arterial blood gases are unnecessary 1
• Use β-hydroxybutyrate measurements (when available) to track ketosis resolution – this is the most accurate marker of successful treatment 1

Identification and Treatment of Precipitating Causes

Treatment of the underlying precipitating cause must occur simultaneously with metabolic correction. 1

Common precipitants requiring immediate attention:

• Infection (most common) – obtain cultures and start appropriate antibiotics promptly 1, 2
• Myocardial infarction – assess troponin and ECG 1, 2
• Cerebrovascular accident – assess for focal neurological deficits 1, 2
• SGLT2 inhibitors – discontinue immediately and do not restart until 3–4 days after metabolic stability 1
• Insulin omission or inadequacy 1
• Medications (corticosteroids, thiazide diuretics, sympathomimetics) 2
• Pancreatitis, trauma, or alcohol abuse 1

Transition to Subcutaneous Insulin

Administer basal insulin (glargine, detemir, or NPH) 2–4 hours BEFORE stopping IV insulin infusion to prevent recurrence of ketoacidosis and rebound hyperglycemia. 1

• Once the patient can tolerate oral intake, initiate a multiple-dose insulin regimen using short/rapid-acting plus intermediate/long-acting insulin 1
• For newly diagnosed patients, start with approximately 0.5–1.0 units/kg/day total daily insulin dose 1
• Recent evidence suggests that adding low-dose basal insulin analog during IV insulin infusion may prevent rebound hyperglycemia without increasing hypoglycemia risk 1

Critical Pitfalls to Avoid

• Starting insulin before correcting hypokalemia (K⁺ <3.3 mEq/L) can cause life-threatening arrhythmias 1
• Stopping insulin when glucose falls to 250 mg/dL (instead of adding dextrose and continuing insulin) leads to recurrent ketoacidosis 1
• Premature termination of insulin therapy before complete resolution of ketosis can lead to DKA recurrence 1
• Using nitroprusside-based ketone tests for monitoring misses β-hydroxybutyrate and may delay appropriate therapy 1
• Correcting osmolality faster than 3 mOsm/kg/hour increases cerebral edema risk 1, 2
• Inadequate potassium monitoring and replacement is a leading cause of mortality in hyperglycemic crisis 1
• Overzealous fluid administration can precipitate noncardiogenic pulmonary edema, particularly in patients with cardiac or renal impairment 1, 2

Disposition and Level of Care

• HHS patients should be immediately evaluated and treated in an intensive care unit due to greater volume depletion, typical triggering by acute illness, and mortality rates up to 15% 2, 3
• Moderate-to-severe DKA or critically ill/mentally obtunded patients require ICU-level care 1
• Mild-to-moderate uncomplicated DKA in hemodynamically stable, alert patients may be managed in a monitored setting with subcutaneous insulin protocols 1

Discharge Planning

Prior to discharge, ensure:

• Identification of outpatient diabetes care providers for follow-up 1
• Patient education on recognition, prevention, and management of hyperglycemic crisis 1
• Appropriate insulin regimen prescribed with attention to medication access and affordability 1
• Sick-day management instructions – never stop basal insulin even when oral intake is limited 1
• Instructions to check ketones when glucose exceeds 200 mg/dL or during any illness 1