Treatment of extreme hyperglycemia monitored with intracerebral microdialysis.

OBJECTIVE

Description of a pediatric patient with hyperosmolar hyperglycemic nonketotic syndrome where the treatment was monitored with intracerebral microdialysis.

DESIGN

Case report.

SETTING

Intensive care unit at a university hospital.

PATIENT

An 11-yr-old boy with new-onset diabetes who presented with a blood glucose concentration of 100 mmol/L (1800 mg/dL) and a serum osmolality of 448 mOsm/kg.

INTERVENTIONS

Interventions included intracerebral and subcutaneous microdialysis as well as intracranial pressure monitoring during correction of the hyperosmolar condition. The strategy was to decrease osmolality by 1 mOsm.kg(-1).hr(-1) and blood glucose by 1.5 mmol.L(-1).hr(-1) (27 mg/dL).

MEASUREMENTS AND MAIN RESULTS

The concentrations of glucose in the subcutaneous dialysates corresponded to the blood glucose concentrations. The brain/subcutaneous glucose ratio varied between 0.20 and 1.28 (mean, 0.43; median, 0.4). When the blood glucose decreased quickly after steady state, the brain/subcutaneous ratio increased sharply, demonstrating that the normalization of glucose in the brain was slower than that in blood.

CONCLUSIONS

Microdialysis can be used to monitor the brain/subcutaneous glucose ratio in patients with extreme hyperglycemia. A rapid decrease in blood glucose increases the brain/subcutaneous glucose ratio, which may be a potential risk factor for osmotic brain edema. Microdialysis may prove to be a valuable tool in treatment management. The child made a full recovery.