RT Journal Article
SR Electronic
T1 Local cortical blood flow and oxygen consumption during isoflurane-induced hypotension
JF Cleveland Clinic Journal of Medicine
JO Cleve Clin J Med
FD Cleveland Clinic
SP 766
OP 770
VO 56
IS 8
A1 Steven Roth
A1 Stephen C. Jones
A1 Zeyd Y. Ebrahim
A1 Harry Friel
A1 John R. Little
YR 1989
UL http://www.ccjm.org/content/56/8/766.abstract
AB Cerebral cortical blood flow (ICoBF) and metabolic rate for oxygen (1CoMRO2) were studied in eight patients undergoing intracranial aneurysm clipping. The patients were anesthetized with fentanyl 10 μg/kg and 70% nitrous oxide combined with 30% oxygen. Hypotension was induced with isoflurane. A thermal diffusion probe was used to measure ICoBF, and arterial and cerebral venous blood samples were obtained for measurement of arterio-cerebral venous O2 content difference. Measurements were made prior to hypotension, during hypotension (to mean arterial pressure approximately 50 mmHg), and posthypotension. Mean ICoBF decreased from 69 ± 20 mL/100 g/min at normotension to 59 ± 13 mL/100 g/min during hypotension (P <.03, NS) and was 61 ± 18 mL/100 g/min upon return to normotension (all values mean ± 1 SD). The lCoMRO2 averaged 3.9 ± 1.6 mL/100 g/min and 3.1 ± 1.5 mL/100 g/min, respectively (P <.03, NS) for normotension v hypotension. Values for cerebral venous PO2 and O2 saturation also did not differ significantly between study periods. These results indicate that isoflurane-induced hypotension during fentanyl-nitrous oxide anesthesia allows maintenance of a constant ICoBF and oxygen delivery.