Cardiac output and regional hemodynamics during recurrent seizures in rats

Altered cardiovascular function in status epilepticus may contribute to mortality and morbidity in patients. We investigated changes in cardiac output and regional hemodynamics during 2 h of recurrent PTZ-induced seizures in anesthetized, paralyzed rats using radioactive microspheres, thermodilution methods, and the pulsed Doppler technique. Cardiac output fell 30-60% during recurrent seizures in 17 of 27 animals. The fall in cardiac output was sudden in onset and occurred primarily in association with seizures accompanied by prolonged increases in MABP but no change in central venous pressure. Total peripheral resistance (TPR) rose during early seizures in association with vasoconstriction of renal and certain splanchnic vascular beds. Ictal increases in TPR became attenuated during late seizures, due to failure of renal and splanchnic beds to constrict. Therefore, derangements in both cardiac and vascular function occur during late seizures. These derangements may contribute to both cerebral hypoperfusion and sudden death in status epilepticus.