Intracranial pressure during nitroglycerin-induced hypotension.
Nitroglycerin was given intravenously to five anesthetized, hyperventilated (PaCO2 25 to 30 torr) patients during craniotomy, to facilitate surgery by creating a relatively bloodless field, and to decrease the potential need to blood transfusion. A subarachnoid screw and an indwelling radial artery catheter were inserted to monitor intracranial pressure (ICP) and mean arterial pressure (MAP). As MAP decreased from 10.4 +/- 4.0 (SE) to 69.0 +/- 1.8 torr, ICP increased from 14.2 +/- 0.7 (SEM) to 30.8 +/- 1.1 torr. Cerebral perfusion pressure decreased from 90.2 +/- 3.6 (SEM) to 38.2 +/- 2.3 torr (p < 0.0005). We attribute this nitroglycerin-induced ICP increase to capacitance vessel dilation within the relatively noncompliant cranial cavity, with subsequent cerebral blood volume increase.
D000328:Adult; D001794:Blood Pressure; D001932:Brain Neoplasms / Q000601:surgery; D006801:Humans; D007023:Hypotension, Controlled / Q000379:methods*; D002538:Intracranial Arteriovenous Malformations / Q000601:surgery; D007427:Intracranial Pressure / Q000187:drug effects*; D008875:Middle Aged; D005996:Nitroglycerin / Q000008:administration & dosage*
D005996:Nitroglycerin