title: Effect of flunarizine on canine cerebral cortical blood flow and vascular resistance post cardiac arrest.
abstract: Twelve dogs were anesthetized and instrumental for determination of CVP, arterial pressure, intracranial pressure, left atrial pressure, and frontal cerebral cortical blood flow (CCBF) by the thermal method. A catheter was introduced into the venous return of the cerebral confluence to allow determination of cerebral A-V oxygen saturation differences. The animals were placed on cardiac bypass using a circuit from the right atrium to the pulmonary artery and a second circuit from the left ventricular apex to the left femoral artery. A heat exchanger was used to maintain a constant blood temperature of 37 C in the output of the left side bypass circuit. All animals were heparinized during bypass. Ventricular fibrillation was induced after completion of the bypass surgery. Two dogs served as controls. Pre-arrest determinations of hemoglobin, glucose, CCBF, and cerebral A-V oxygen differences were taken. Full circulatory arrest was carried out for 20 minutes by shutting off the cardiac bypass. Resuscitation was achieved by resumption of bypass perfusion. Acid-base balance was corrected quickly, and pre-arrest perfusion pressure was achieved and maintained for 90 minutes. All pressure parameters were monitored continuously. All pre-arrest determinations were repeated at 20, 40, 60, and 90 minutes post resuscitation. Five dogs were treated with 6 microgram/kg flunarizine administered IV drip over 10 minutes immediately post reperfusion. Five dogs were not treated post arrest. Treated animals had a prompt return of CCBF rates equal to or greater than pre-arrest flow, which persisted throughout the period of post-arrest observation. Untreated animals had markedly reduced CCBF and increased resistance. CCBF uniformly proceeded to near zero flow by 90 minutes. The ICP was not significantly altered by treatment.
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002118:Calcium / Q000037:antagonists & inhibitors* / Q000378:metabolism; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D002936:Cinnarizine / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000494:pharmacology*; D004285:Dogs; D005444:Flunarizine; D006323:Heart Arrest / Q000378:metabolism / Q000503:physiopathology*; D007427:Intracranial Pressure / Q000187:drug effects; D008954:Models, Biological; D010879:Piperazines / Q000494:pharmacology*; D012151:Resuscitation; D014655:Vascular Resistance / Q000187:drug effects*
chemical_list: D010879:Piperazines; D002936:Cinnarizine; D005444:Flunarizine; D002118:Calcium