Management of DKA with Blood Glucose Above 700 mg/dL
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), followed by continuous IV insulin infusion at 0.1 units/kg/hour once potassium is ≥3.3 mEq/L, and add dextrose to fluids when glucose falls to 250 mg/dL while continuing insulin until ketoacidosis resolves. 1, 2
Initial Assessment and Diagnosis
Confirm DKA diagnosis with: blood glucose >250 mg/dL (yours is >700 mg/dL), arterial pH <7.3, serum bicarbonate <15 mEq/L, and presence of ketonemia or ketonuria 1, 2
Obtain immediate labs: plasma glucose, arterial blood gases, complete blood count with differential, serum electrolytes with calculated anion gap, blood urea nitrogen, creatinine, serum ketones (β-hydroxybutyrate preferred), osmolality, urinalysis, and electrocardiogram 1, 2
Identify precipitating factors: infection (most common at 30-50% of cases), myocardial infarction, stroke, trauma, pancreatitis, insulin omission, or SGLT2 inhibitor use 1, 3
Obtain bacterial cultures (urine, blood, throat) if infection suspected and start appropriate antibiotics 1, 2
Fluid Resuscitation Protocol
The extremely high glucose level (>700 mg/dL) indicates severe dehydration requiring aggressive initial fluid replacement:
Start with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour during the first hour (1-1.5 L for average adult) to restore intravascular volume and renal perfusion 1, 2
After the first hour, switch to 0.45% NaCl at 4-14 mL/kg/hour if corrected serum sodium is normal or elevated; continue 0.9% NaCl if corrected sodium is low 2
Calculate corrected sodium: add 1.6 mEq to measured sodium for each 100 mg/dL glucose above 100 mg/dL 2, 1
Total fluid replacement should correct estimated deficits (typically 6 L in DKA) within 24 hours, with osmolality change not exceeding 3 mOsm/kg/H₂O per hour 2, 1
Insulin Therapy
Critical: Do NOT start insulin if potassium <3.3 mEq/L—correct potassium first to prevent life-threatening cardiac arrhythmias: 1
Once potassium ≥3.3 mEq/L, start continuous IV regular insulin infusion at 0.1 units/kg/hour (no initial bolus needed in most protocols) 1, 4
If glucose does not fall by 50 mg/dL in the first hour, check hydration status; if adequate, double the insulin infusion rate hourly until steady glucose decline of 50-75 mg/dL per hour is achieved 1, 2
When glucose reaches 250 mg/dL, add 5% dextrose to 0.45-0.75% NaCl solution while continuing insulin infusion—this is critical to prevent hypoglycemia while allowing continued insulin therapy to clear ketones 1, 4
Target glucose of 150-200 mg/dL until DKA resolves; never stop insulin when glucose normalizes, as ketoacidosis takes longer to clear than hyperglycemia 1, 5
Continue insulin infusion until DKA resolution: pH >7.3, serum bicarbonate ≥18 mEq/L, anion gap ≤12 mEq/L, and glucose <200 mg/dL 1, 2
Electrolyte Management
Potassium replacement is critical despite normal or elevated initial levels, as total body potassium is universally depleted in DKA:
If K⁺ <3.3 mEq/L: Hold insulin and aggressively replace potassium until ≥3.3 mEq/L to prevent cardiac arrhythmias and respiratory muscle weakness 1
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 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 4-5 mEq/L throughout treatment 1
Bicarbonate is NOT recommended for pH >6.9-7.0—studies show no benefit in resolution time or outcomes, and it may worsen ketosis, cause hypokalemia, and increase cerebral edema risk 1, 4
Monitoring During Treatment
Draw blood every 2-4 hours for serum electrolytes, glucose, blood urea nitrogen, creatinine, osmolality, and venous pH 1, 2
Venous pH is adequate for monitoring (typically 0.03 units lower than arterial pH); repeat arterial blood gases are generally unnecessary 1, 4
Monitor for signs of cerebral edema (especially in younger patients): lethargy, behavioral changes, seizures, incontinence, pupillary changes, bradycardia, respiratory arrest 4
Direct measurement of β-hydroxybutyrate in blood is preferred over urine ketones for monitoring DKA resolution 1, 5
Transition to Subcutaneous Insulin
Once DKA is resolved (pH >7.3, bicarbonate ≥18 mEq/L, anion gap ≤12 mEq/L):
Administer basal subcutaneous insulin (intermediate or long-acting) 2-4 hours BEFORE stopping IV insulin infusion to prevent recurrence of ketoacidosis and rebound hyperglycemia 1, 4
This overlap period is essential—premature termination of IV insulin is a common cause of DKA recurrence 1, 6
Start multiple-dose subcutaneous insulin regimen with combination of rapid/short-acting and intermediate/long-acting insulin when patient can eat 1, 5
Critical Pitfalls to Avoid
Never stop insulin infusion when glucose falls below 250 mg/dL—this is the most common error; instead add dextrose and continue insulin until ketoacidosis resolves 1, 6
Never start insulin before excluding hypokalemia (K⁺ <3.3 mEq/L)—insulin drives potassium intracellularly and can precipitate life-threatening arrhythmias 1
Inadequate potassium monitoring and replacement is a leading cause of mortality in DKA 1
Overly rapid correction of osmolality (>3 mOsm/kg/H₂O per hour) increases cerebral edema risk 2, 4
Insufficient timing or dosing of subcutaneous insulin before discontinuing IV insulin leads to rebound hyperglycemia 6, 1