In vivo multiparametric monitoring of brain functions under intracranial hypertension following mannitol administration.
OBJECTIVE
Over the last 20 years, mannitol has replaced other osmotic diuretics. Its beneficial effects on intracranial pressure (ICP), cerebral perfusion pressure (CPP), cerebral blood flow (CBF) and brain metabolism are widely accepted. In the present study, we tested the effect of mannitol injection on brain hemodynamic, metabolic, ionic and electrical state in rats exposed to intracranial hypertension.


METHODS
The parameters monitored simultaneously included ICP, CBF using the laser Doppler flowmetry, mitochondrial NADH redox state by the fluorometric technique, extracellular K(+) and H(+) levels, DC potential, ECoG, blood pressure and calculated CPP. ICP was elevated to 30 mmHg for 30 minutes and mannitol was injected 15 minutes post-ICP elevation.


RESULTS
Our results showed that mannitol decreased ICP, and improved the levels of MAP, CPP and CBF. Moreover, mannitol completely prevented mortality following intracranial hypertension in rats.


CONCLUSIONS
It seems that the multiparametric monitoring approach, used in intracranial hypertension models, is an important tool for brain functional state evaluation.
Barbiro-Michaely
Efrat
E
Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel.
Mayevsky
Avraham
A
Knoller
Nachshon
N
Hadani
Moshe
M
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D001921:Brain / Q000187:drug effects* / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000187:drug effects; D004195:Disease Models, Animal; D004234:Diuretics, Osmotic / Q000008:administration & dosage*; D005110:Extracellular Space / Q000187:drug effects; D019585:Intracranial Hypotension / Q000188:drug therapy* / Q000503:physiopathology; D007427:Intracranial Pressure / Q000187:drug effects; D017078:Laser-Doppler Flowmetry / Q000379:methods; D008297:Male; D008353:Mannitol / Q000008:administration & dosage*; D008991:Monitoring, Physiologic / Q000379:methods; D009243:NAD / Q000378:metabolism; D010084:Oxidation-Reduction / Q000187:drug effects; D011188:Potassium / Q000378:metabolism; D011522:Protons; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
D004234:Diuretics, Osmotic; D011522:Protons; D009243:NAD; D008353:Mannitol; D011188:Potassium