What is the most appropriate treatment for a 12-year-old patient with moderate diabetic ketoacidosis (DKA) who becomes disoriented with a decreased Glasgow Coma Scale (GCS) score after starting DKA management protocol?

Immediate Treatment: IV Mannitol for Suspected Cerebral Edema

The most appropriate treatment is B. IV mannitol, as this patient is exhibiting signs of cerebral edema—the most life-threatening complication of DKA treatment in children.

Clinical Reasoning

This 12-year-old with moderate DKA developed acute neurological deterioration (disorientation, GCS drop from 15 to 13) one hour after starting standard DKA management. This presentation is highly concerning for cerebral edema, which is the leading cause of death in pediatric DKA 1, 2.

Why Cerebral Edema is the Primary Concern

• Cerebral edema in DKA typically manifests with subtle neurological symptoms including headache, lethargy, or disorientation, with GCS scores of 14-15 (subclinical cerebral edema) 3.
• This patient's GCS of 13 with disorientation after initiating treatment fits the classic presentation of subclinical to overt cerebral edema 3.
• The American Diabetes Association emphasizes monitoring closely for cerebral edema during treatment, especially with overly aggressive fluid resuscitation 1.
• Cerebral edema occurs more commonly in children and adolescents than adults and is one of the most dire complications of DKA 4.

Treatment Protocol for Cerebral Edema

Immediate hyperosmolar therapy with mannitol is indicated 2, 3:

• Treatment of subclinical cerebral edema with hyperosmolar therapy for persistent symptoms is associated with good outcomes 3.
• Mannitol should be administered promptly when cerebral edema is suspected, as emphasized in DKA management guidelines 2.
• The typical dose is 0.5-1.0 g/kg IV over several minutes 5.

Why Other Options Are Incorrect

Option A: CT Brain

• While CT may eventually be needed to confirm cerebral edema, treatment should not be delayed waiting for imaging 2.
• The clinical diagnosis of cerebral edema in DKA is sufficient to initiate hyperosmolar therapy 3.
• Delaying mannitol administration to obtain imaging can worsen outcomes in this time-sensitive emergency 2.

Option C: Increase Insulin Infusion

• This would be dangerous and contraindicated 1.
• Rapid glucose decline and osmolar shifts contribute to cerebral edema development 2.
• The American Diabetes Association recommends a target glucose decline of only 50-75 mg/dL per hour to prevent cerebral edema 1, 4.
• Increasing insulin would accelerate osmolar shifts and potentially worsen cerebral edema 1.

Option D: Normal Saline 20 mL/kg Over 15 Minutes

• This would be extremely dangerous in suspected cerebral edema 1, 2.
• Overly aggressive fluid resuscitation is a major risk factor for cerebral edema in pediatric DKA 1, 2.
• The American Diabetes Association specifically warns against overhydration as it contributes to cerebral edema 1.
• Rapid fluid boluses can worsen cerebral edema through increased intracranial pressure 2.

Critical Management Principles

Monitoring Requirements

• Continuous neurological assessment is essential during DKA treatment, with particular attention to mental status changes, headache, or neurological deterioration 4.
• The American Diabetes Association recommends monitoring vital signs, neurologic status, and response to treatment every 2-4 hours 1, 4.

Prevention of Cerebral Edema

• Avoid overly rapid correction of osmolality, which increases cerebral edema risk, particularly in children 4.
• Initial fluid resuscitation should be isotonic saline at 15-20 mL/kg/hour, not rapid boluses 1, 4.
• Target gradual glucose decline of 50-75 mg/dL per hour 1, 4.

Common Pitfall to Avoid

• Never attribute altered mental status in DKA solely to hyperglycemia or acidosis after treatment has begun 2, 3. Any neurological deterioration during DKA treatment should be presumed to be cerebral edema until proven otherwise, and hyperosmolar therapy should be initiated immediately 2, 3.