Summary
Pediatric diabetic ketoacidosis is defined by hyperglycemia, metabolic acidosis, and ketosis, and its management balances correcting fluid and electrolyte deficits against the specific pediatric risk of cerebral injury [1]. The fluid strategy in children is more conservative than in adults, where higher-volume resuscitation is standard, and the two-bag system is a practical way to titrate dextrose without changing the electrolyte or rate prescription [1][4].
- Diagnosis requires hyperglycemia, venous pH below 7.3 or bicarbonate below 18 mmol/L, and ketonemia or ketonuria [1].
- Fluid replacement is deliberately measured. A large randomized trial found that neither the rate nor the sodium content of rehydration, within the ranges tested, altered neurologic outcome, which removed the rationale for extreme fluid restriction [2].
- Insulin is started after initial volume expansion, typically at 0.05 to 0.1 units per kilogram per hour, and is not preceded by a bolus in children [1].
- Cerebral injury is the feared complication and remains a leading cause of death in pediatric diabetic ketoacidosis, so serial neurologic checks are part of the protocol, not an afterthought [1][3].
Caution. Potassium is total-body depleted even when the serum value is normal or high, because acidosis shifts potassium out of cells. Insulin drives it back in and can precipitate dangerous hypokalemia. The guideline defers potassium replacement if the child is hyperkalemic above 5.5 mmol/L until urine output is documented, and defers insulin in the rare child with potassium below 3.0 mmol/L until potassium is given, so check potassium before starting insulin and include potassium in the fluids once it is below 5.5 mmol/L [1].
Diagnosis
The biochemical triad defines the diagnosis, and severity is graded by the degree of acidosis rather than by the glucose level [1].
| Severity |
Venous pH |
Bicarbonate |
| Mild |
< 7.3 |
< 18 mmol/L |
| Moderate |
< 7.2 |
< 10 mmol/L |
| Severe |
< 7.1 |
< 5 mmol/L |
Glucose can be only modestly elevated in euglycemic ketoacidosis, so the diagnosis rests on acidosis and ketosis, not on a glucose threshold [1].
Fluid strategy
Rehydration is calculated as the estimated deficit added to maintenance and replaced evenly, typically over 24 to 48 hours [1]. The randomized evidence supports moderate rehydration rather than either aggressive or highly restrictive fluids [2].
Estimate the fluid deficit from degree of dehydration in Fluid Deficit →
Calculate maintenance requirements in Maintenance Fluids →
The two-bag system uses two bags with identical electrolyte composition, one with dextrose and one without, running into the same line. Adjusting the relative rate of the two bags changes the delivered dextrose concentration in seconds while holding the total fluid rate, sodium, and potassium constant. This lets the team respond to a falling glucose without interrupting insulin or rewriting the order.
Set up the two-bag rates and delivered dextrose in DKA Two-Bag →
Insulin and transition
Insulin infusion follows initial volume expansion and continues until the acidosis clears, which is the endpoint rather than a normal glucose [1]. Add dextrose to the fluids, through the two-bag system, once glucose falls to around 250 to 300 mg/dL so that insulin can continue clearing ketones without producing hypoglycemia [1]. The acidosis, not the glucose, dictates when the infusion stops.
Transition to subcutaneous insulin occurs after the acidosis resolves and the child can eat, with the first subcutaneous dose given before the infusion is stopped to avoid a gap in coverage [1]. In an established patient, the home insulin-to-carbohydrate ratio informs mealtime dosing once the child returns to oral intake.
Estimate mealtime insulin from the carbohydrate ratio in Insulin-Carb Ratio →
Cerebral injury typically appears in the first several hours to a day of treatment, often heralded by headache, recurrence of vomiting, rising blood pressure with falling heart rate, or a declining level of consciousness [3]. Recognize it clinically and treat immediately, because it does not wait for imaging [1][3].
References
- Glaser N, Fritsch M, Priyambada L, et al. ISPAD Clinical Practice Consensus Guidelines 2022: diabetic ketoacidosis and hyperglycemic hyperosmolar state. Pediatr Diabetes. 2022;23(7):835-856. doi:10.1111/pedi.13406
- Kuppermann N, Ghetti S, Schunk JE, et al. Clinical trial of fluid infusion rates for pediatric diabetic ketoacidosis. N Engl J Med. 2018;378(24):2275-2287. doi:10.1056/NEJMoa1716816
- Glaser NS, Wootton-Gorges SL, Marcin JP, et al. Cerebral injury and cerebral edema in children with diabetic ketoacidosis. Pediatr Diabetes. 2009;10(8):534-541. doi:10.1111/j.1399-5448.2009.00511.x
- Kitabchi AE, Umpierrez GE, Miles JM, Fisher JN. Hyperglycemic crises in adult patients with diabetes. Diabetes Care. 2009;32(7):1335-1343. doi:10.2337/dc09-9032