Diabetic ketoacidosis: cerebral oedema occurred with excessive free water administration.

Clinical bottom line (level 4)

  1. Around a tenth of patients with diabetic ketoacidosis suffered complications of brain swelling (mostly minor). 3% died.
  2. Patients with diabetic ketoacidosis whose serum sodium concentration fell or failed to rise during rehydration were at increased risk of developing cerebral oedema (NNF = 8 for unknown) .
Harris et al: Journal of Pediatrics 1990; 117 (1): 22-31
Expires October 2003

The study

Retrospective cohort study with unblinded, unobjective outcomes, not adjusted for confounding factors, not validated in an independent set of patients.

Setting: two acute hospitals, USA, 1962-1988

119 patients (aged range 13 months to 30 years, 58% female) with 219 episodes of moderate or severe diabetic ketoacidosis (ketonaemia with pH 7.15 or more, or pH <7.15 respectively)

Excluded if
  • incomplete documentation



    • Factors studied:
  • complications, death
  • serum sodium concentration fell or failed to rise


    • All patients were rehydrated over 24 hours.


    Outcomes studied:
  • complications headache, acute deterioration in vital signs or neurologic status or both, death
  • death or near death

    • The evidence

    outcome time to outcome number of patients/total number %
    (95% CI)
    complications ? 20/219 9.1%
    (5.2% to 13%)
    death or near death ? 7/219 3.2%
    (0.9% to 5.5%)

    prognostic factor for
    complications     		time to outcome unadjusted RR
    (95% CI)    		 NNF+
    (95% CI)
    serum sodium concentration fell or failed to rise ? 6.56
    (1.56 to 27.5)     		8
    (2 to 76)

    • Failure of serum sodium concentration to rise indicates excessive administration of free water.
    • Forty patients were followed prospectively on a 48 hour treatment plan providing sodium and water replacement evenly- only two minor complications occurred (5%: 95% CI: 0.0% to 12%).

    Citation

    1. Harris GD, Fiordalisi I, Harris WL, et al: Minimizing the risk of brain herniation during treatment of diabetic ketoacidemia: a retrospective and prospective study. Journal of Pediatrics 1990; 117 (1): 22-31
    Search Terms: reference in review article
    Contributor: Chris Ball and Clare Wotton, July 2000
    Reviewer:

    Clinical Question.
    Patient DKA
    Intervention or Exposure serum sodium concentration
    Outcome cerebral oedema