The effect of norepinephrine versus epinephrine on regional cerebral blood flow during cardiopulmonary resuscitation.
alpha-Adrenergic drugs improve cerebral blood flow (CBF) during cardiopulmonary resuscitation (CPR), in part, by reversing carotid artery collapse and by shunting blood from extracerebral to intracerebral vascular structures. Adrenergic drugs with beta 2-agonist properties may cause peripheral vasodilation, and thus may be less beneficial in this setting. The purpose of this study was to compare epinephrine (E), an alpha 1,2, beta 1,2-agonist, with norepinephrine (NE), an alpha 1,2, beta 1-agonist, on CBF during CPR. Twenty swine each weighing greater than 15 kg were instrumented for regional CBF measurements using tracer microspheres. Regional CBF was measured during normal sinus rhythm (NSR). Animals were then placed into ventricular fibrillation (VF). After ten minutes of VF, the animals received closed-chest CPR using a mechanical thumper. Regional CBF was measured during CPR. After three minutes of CPR, the animals were allocated to receive either E, 0.20 mg/kg (N = 5); NE, 0.08 mg/kg (N = 5); NE, 0.12 mg/kg (N = 5); or NE, 0.16 mg/kg (N = 5). Regional blood flows were again measured following drug administration. CBFs following drug administration were compared using an analysis of covariance adjusting for baseline differences during CPR. A Newman-Keuls multiple comparison was used to follow-up significant (P less than or equal to .05) differences. Statistical significance was considered at P less than or equal to .05. There was a clinically significant improvement in cerebral cortical flow with NE, 0.12 mg/kg, and NE, 0.16 mg/kg, compared with NE, 0.08 mg/kg.(ABSTRACT TRUNCATED AT 250 WORDS)
Brown
C G
CG
Division of Emergency Medicine, Ohio State University, Columbus 43210.
Robinson
L A
LA
Jenkins
J
J
Bowman
K
K
Schlaifer
J
J
Werman
H
H
Ashton
J
J
Hamlin
R L
RL
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D004837:Epinephrine / Q000494:pharmacology*; D009638:Norepinephrine / Q000494:pharmacology*; D012039:Regional Blood Flow / Q000187:drug effects; D012151:Resuscitation; D013552:Swine
D009638:Norepinephrine; D004837:Epinephrine