title: Cerebral metabolism and intracranial hypertension in high grade aneurysmal subarachnoid haemorrhage patients.
abstract: We evaluated the effect of intracranial hypertension on cerebral metabolism in patients with high grade aneurysmal subarachnoid hemorrhage (SAH) using bedside cerebral microdialysis (MD). Thirty-six patients with SAH were studied and classified into two groups (intracranial pressure, ICP > 20 mmHg, n = 25) and (ICP < 20 mmHg, n = 11). ICP was monitored hourly using an intraventricular drainage (n = 36). The MD catheter was placed after aneurysm clipping into the vascular territory of interest and was perfused with Ringer's solution (0.3 microl/min). The MD samples were collected hourly for measurements of glucose, lactate, and glutamate (CMA 600, Sweden). Lactate/pyruvate ratio was also calculated. To calculate group specific differences, the 24 hours median values of the first 7 days after SAH were compared. Differences were considered statistically significant at P < 0.05. Patient groups were comparable for age, severity of SAH, Fisher's grade and duration of MD sampling. In patients with ICP > 20 mmHg from day 1 to 7 after SAH, extracellular concentrations of glucose were significantly lower, while the lactate/ pyruvate ratio was higher compared to SAH patients with normal ICP values. The differences between groups in glutamate levels was only significant on day 1 after SAH due to high inter-individual differences. We concluded that intracranial hypertension in associated with an anaerobic cerebral metabolism indicated cerebral ischemia in high grade SAH patients.
authors.affiliation: Department of Neurosurgery, Charité Campus Virchow Medical Center, Humboldt University of Berlin, Berlin, Germany. asita.sarrafzadeh@charite.de
authors.forename: A S
authors.initials: AS
authors.lastname: Sarrafzadeh
authors.forename: U W
authors.initials: UW
authors.lastname: Thomale
authors.forename: D
authors.initials: D
authors.lastname: Haux
authors.forename: A W
authors.initials: AW
authors.lastname: Unterberg
mesh_terms: D001921:Brain / Q000503:physiopathology; D005260:Female; D006801:Humans; D019586:Intracranial Hypertension / Q000175:diagnosis* / Q000209:etiology / Q000378:metabolism*; D007427:Intracranial Pressure; D008297:Male; D017551:Microdialysis / Q000379:methods; D008875:Middle Aged; D018377:Neurotransmitter Agents / Q000378:metabolism*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013223:Statistics as Topic; D013345:Subarachnoid Hemorrhage / Q000150:complications / Q000175:diagnosis* / Q000378:metabolism*
chemical_list: D018377:Neurotransmitter Agents