抄録
In recent years, the development of secondary brain damage and the derangement of neurochemical parameters have been monitored by microdialysis in patients experiencing severe head injuries. Glycerol is regarded as a potential marker for membrane phospholipid degradation and can provide information on the integrity of the blood brain barrier. We introduce a case in which a marked elevation of interstitial glycerol was induced by the exogenous administration of a glycerol-containing agent. A 25-year-old man who had been in a motorcycle accident was admitted to our hospital with a unilateral dilated and fixed pupil and a Glasgow Coma Scale score of three. Computed tomographic scans showed a large left subdural hematoma, a subsequent midline shift, and generalized edema. An emergency craniotomy was performed to remove the hematoma. The patient was then prepared for multisensory monitoring using microdialysis. A microdialysis catheter was inserted in the left frontal lobe. After a routine enema (containing 85% glycerol), a marked increase in the amount of glycerol within the dialysate was measured. This event occurred while the patient was in as stable a condition as could be expected, under the circumstances. An increase in interstitial glycerol in the injured tissue is most likely due to an impaired blood-brain-barrier. Thus, the interstitial glycerol concentration was corrupted by the exogenous glycerol, causing the marker properties of interstitial glycerol to become questionable. Consequently, the administration of glycerol, which is a frequent constituent of various infusions and emulsions, could promote secondary brain damage by adversely shifting osmotic gradients.
