Adapted from Muir et al, Diabetes Care, 2004 here is a protocol/schema that can guide in the assessment of cerebral edema in DKA. Recall that the symptoms of cerebral edema vary, and it can be especially difficult to diagnose as findings will occur ahead of CT/MRi changes. One-half to 1% of patients in DKA have cerebral edema, the mortality of which approaches 20%. The authors noted that in their small sample it was 92% specific and 96% sensitive.

You should use this tool only after therapy (insulin/fluids) has begun. You should suspect cerebral edema if:

Any diagnostic criteria
   OR
2 major criteria
   OR
1 major and 2 minor

Diagnostic criteria

  • Abnormal motor or verbal response to pain
  • Decorticate or decerebrate posture
  • Cranial nerve palsy (especially III, IV, and VI)
  • Abnormal neurogenic respiratory pattern (eg, grunting, tachypnea, Cheyne-Stokes, apneusis)

Major criteria

  • Altered mentation/fluctuating level of consciousness
  • Sustained heart rate deceleration (≥ 20 beats per minute) not attributable to improved intravascular volume or sleep state
  • Age-inappropriate incontinence

Minor criteria

  • Vomiting
  • Headache
  • Lethargy or being not easily aroused from sleep
  • Diastolic blood pressure >90 mmHg
  • Age <5 years