Hyperglycemia and cerebral glucose in aneurysmal subarachnoid hemorrhage.
OBJECTIVE
To determine whether hyperglycemia exerts deleterious effects via cerebral energy metabolism and to illuminate the effects of cerebral high/low glucose in patients with aneurysmal subarachnoid hemorrhage.


METHODS
Prospective, nonrandomized single-center study over a 2-year period in an intensive care unit at a primary-level university hospital.


METHODS
28 subarachnoid hemorrhage patients (age 53 +/- 10 years, WFNS grade 2.8 +/- 1.5) classified as asymptomatic (n = 5) or symptomatic with acute focal or delayed ischemic neurological deficits (n = 23).


RESULTS
Hyperglycemia (> 7.8 mmol/l; >140 mg/dl) was more frequent in symptomatic patients and was reflected in higher glycerol concentrations than in asymptomatic patients. In all patients a microdialysis catheter was inserted into the tissue at risk; dialysates were collected hourly for 10 days. Cerebral low-glucose episodes (0.6 mmol/l) and high-glucose episodes (>2.6 mmol/l) occurred independently of blood glucose levels. During high-glucose episodes cerebral microdialysate levels were normal, while cerebral low glucose, occurring more frequently in symptomatic patients, was associated with severe cellular distress (increase in lactate/pyruvate ratio, glutamate, glycerol) and with unfavorable outcome if combined with hyperglycemia.


CONCLUSIONS
Although hyperglycemia was more frequent in symptomatic patients and associated with high glycerol levels, hyperglycemia was not related to cerebral high glucose. It appears that the association of adverse outcome with acute-phase hyperglycemia is not mediated by cerebral glucose metabolism. Cerebral low glucose was associated with severe metabolic distress and may present a target for therapy to improve clinical outcome.
Schlenk
Florian
F
Department of Neurosurgery, Charité Campus Virchow Medical Center, Augustenburger Platz 1, 13353, Berlin, Germany.
Nagel
Alexandra
A
Graetz
Daniela
D
Sarrafzadeh
Asita S
AS
D004734:Energy Metabolism; D005260:Female; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D006943:Hyperglycemia / Q000150:complications* / Q000378:metabolism*; D007362:Intensive Care Units; D002532:Intracranial Aneurysm / Q000150:complications*; D008297:Male; D017551:Microdialysis; D008875:Middle Aged; D011446:Prospective Studies; D013345:Subarachnoid Hemorrhage / Q000145:classification / Q000209:etiology* / Q000378:metabolism*
D005947:Glucose