Outline Guide to Management of Diabetic Ketoacidosis in Adults

By Dr. V. Lavis Last revision 12/19/03 1:47 PM

Reference: Diabetes Care 2002; 25(Suppl. 1):S100-S108

Initial diagnostic measures

First priority measures

• Rapid examination for airway, cardiovascular function, neurologic status, signs of infection
• Capillary blood glucose and urinary ketones
• Stat blood work: arterial gases, serum Na, K, Cl, HCO3-, glucose, creatinine, BUN; CBC. Calculate serum osmolality and anion gap
• Stat ECG
• Start a flow sheet

Initial general medical data

• Chest film if indicated
• Cultures: blood, urine, sputum

Initial therapy

General

• NG tube if patient is unconscious or vomiting.
• Hemodynamic monitoring if there is suspicion of LV failure or cardiogenic shock.
• DVT prophylaxis, especially if patient is unconscious or severely volume-depleted.

Fluids

• 0.9% saline: 1 L in 30 min; then 1 L in next 1 hour; then 1 L in next 2 hours; then 2 L in next 8 hours
• Switch to 0.45% saline if osmolality increases during administration of saline, or if [serum Na + 0.016 • (serum glucose – 100)] > 145.

Insulin

• Check serum K. Hold insulin if K<3.3 mEq/L. Give KCl at 40 mEq/h, until K≥3.3 mEq/L.
• Load with 0.15 units/kg Regular, IV; then start infusion at 0.1 units/kg/h.
• Double rate of infusion if glucose does not fall by at least 50 mg/dl in 1 h. Double rate hourly, until glucose falls by at least 50 mg/dl/h.

Potassium

• Be sure patient is making urine.
• If K<3.3 mEq/L, hold insulin. Give 40 mEq K/h, until K≥3.3 mEq/L.
• If K between 3.3 and 4 mEq/L, give 25 mEq K/h.
• If K between 4 and 5 mEq/L, give 20 mEq K/h.
• If K rises above 5 mEq/L, stop giving K; check K level q2h.
• K infusion should be 2/3 as KCl, 1/3 as K phosphate.
• Adjust rate of K infusion to keep serum K between 4 and 5 mEq/L.
• Monitor ECG as guide to extracellular [K+]

Alkali

• If arterial pH>7.0, no need for bicarbonate
• For pH 6.9 - 7.0, may give 44 mEq NaHCO3, with 10 - 15 mEq K+, over 30 min
• For pH <6.9, give 88 mEq NaHCO3, with 25 mEq K+, over 45 min
• 30 min after each infusion of NaHCO3, re-check pH, and re-evaluate need for more alkali

Phosphate

• Patients in DKA are usually phosphate depleted, but not hypophosphatemic on admission; serum phosphate usually falls during therapy
• Controlled studies have failed to show a beneficial effect of intravenous phosphate replacement on clinical outcome, in diabetic ketoacidosis.
• Do not give IV phosphate if patient is hyperphosphatemic, hypercalcemic, hypocalcemic, azotemic or oliguric
• Check P level initially and 8 hr. after starting insulin
• If [P] <1 mg/dL, may give neutral K phosphate, 10 - 20 millimoles per liter of IV fluids
• Do not add phosphate to solutions containing calcium
• Monitor serum Ca, P and creatinine q12 h, while giving IV phosphate
• Safest way to replete phosphate is orally, after patient can take oral feedings

Continued management

Check capillary glucose hourly

• When glucose down to 250 mg/dL:
  • Switch to fluids containing 5% or 10% dextrose, until patient can eat
  • Patient will develop a non-anion-gap acidosis, during the treatment. Continue insulin infusion at therapeutic rate of at least 5 units/hr, until the acidosis has cleared (i.e. [HCO3‑] >18 mEq/L). Give dextrose-containing fluids as needed to avoid hypoglycemia
  • After acidosis has cleared, continue insulin infusion at maintenance rate of 0.5 ‑ 2 units/hr, until patient can eat
  • Keep giving IV K+ at about 3 - 5 mEq/hr, until patient begins eating

When acidosis has cleared and patient can eat, start NPH insulin

• Wait at least 1 hr after giving NPH insulin, before stopping the insulin infusion.
• Remember that a Type 1 diabetic patient will require NPH insulin twice daily
• Continue oral K+ and phosphate repletion for 5 to 7 days