Stroke, Vol 22, 889-895, Copyright © 1991 by American Heart Association
Effects of U74006F on multifocal cerebral blood flow and metabolism after cardiac arrest in dogs
F Sterz, P Safar, DW Johnson, K Oku and SA Tisherman
International Resuscitation Research Center, University of Pittsburgh, Pa 15260.
Lipid peroxidation reactions during reperfusion after cardiac arrest may
contribute to postischemic cerebral hypoperfusion, which in turn can
contribute to permanent neurological dysfunction. We designed this study to
determine whether the aminosteroid U74006F, a putative inhibitor of lipid
peroxidation, mitigates cerebral multifocal hypoperfusion after cardiac
arrest. We used our established dog model of ventricular fibrillation
cardiac arrest (no blood flow) of 12.5 minutes, reperfusion by
cardiopulmonary bypass of less than or equal to 5 minutes, and control of
extracerebral variables during 4 hours postarrest. Cerebral blood flow was
monitored by the stable xenon computed tomography method. Changes in
cerebral oxygen consumption were obtained from mean blood flow values of
coronal slices and the cerebral arteriovenous (sagittal sinus) oxygen
content difference. A treatment group (n = 5) received U74006F starting
with reperfusion (1.5 mg/kg i.a. plus 1.5 mg/kg i.v.) and three additional
(graded) doses over 4 hours (total dose 4.5, 7.5, or 14.5 mg/kg). The
U74006F-treated group showed the same postarrest transient hyperemia and
protracted hypoperfusion in terms of global (computed tomography slice),
regional, and local (multifocal) cerebral blood flow values and the same
global cerebral oxygen consumption pattern as a concurrent control group (n
= 5). At 1-4 hours postarrest, in both groups there was mismatching of
global cerebral oxygen consumption, which reached baseline values, in
relation to global cerebral blood flow and oxygen delivery, which remained
at 50% of baseline. We conclude that treatment with U74006F after prolonged
cardiac arrest causes no deleterious side effects and does not seem to
alter multifocal postarrest cerebral blood flow and oxygen consumption.