title: Cerebral blood flow during early cardiopulmonary bypass in man. Effect of procaine in cardioplegic solutions.
abstract: Cerebral blood flow (CBF), plasma procaine concentrations, and somatosensory evoked potentials (SSEP) were recorded in 2 groups of patients in whom either a high-procaine cardioplegic solution (Bretschneider's n = 29), or a low-procaine cardioplegic solution (St. Thomas', n = 13) was used. In the Bretschneider's group, marked changes in CBF occurred (p less than 0.001). Mean CBF was 27 (range 18 to 51) ml/(100 g X min) between sternotomy and the onset of extracorporeal circulation (ECC). A mean of 6 minutes after the onset of ECC, and before the administration of Bretschneider's cardioplegic solution, CBF increased to 39 ml/(100 g X min). After administration of the cardioplegic solution, CBF decreased significantly within the first 15 minutes, and then gradually increased to a mean of 68 (range 43 to 108) ml/(100 g X min). Cerebral blood flow was 45 ml/(100 g X min) just after ECC was stopped. Marked plasma procaine concentrations, up to 100 mg/l, were reached just after the infusion of Bretschneider's solution. The flow was significantly reduced (p less than 0.015) in patients with plasma procaine greater than or equal to 10 mg/l, when compared to patients with plasma procaine values less than 10 mg/l. In the St. Thomas' cardioplegic solution group the same reduction in CBF did not occur (p less than 0.02). Despite the depressant effect of procaine on CBF in the Bretschneider group, a consistent brain hyperperfusion was observed in all patients during hypothermic ECC if their blood pressure was sufficient to produce hyperemia. In rats (n = 6), during normothermia without extracorporeal circulation, the effect of procaine was much more pronounced. The CBF fell from a mean resting level of 108 ml/(100 g X min) to 68 and 54 ml/(100 g X min) after 15 and 35 minutes, respectively, of continuous infusion of Bretschneider's solution. The flow returned to the resting level about 40 minutes after termination of the infusion.
mesh_terms: D000328:Adult; D000818:Animals; D001021:Aortic Valve / Q000601:surgery; D001024:Aortic Valve Stenosis / Q000151:congenital / Q000601:surgery; D002315:Cardiopulmonary Bypass; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D005071:Evoked Potentials / Q000187:drug effects; D005260:Female; D005947:Glucose / Q000494:pharmacology*; D006324:Heart Arrest, Induced; D006801:Humans; D008297:Male; D008353:Mannitol / Q000494:pharmacology*; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery; D011189:Potassium Chloride / Q000494:pharmacology*; D011343:Procaine / Q000097:blood / Q000494:pharmacology*; D051381:Rats; D013997:Time Factors
chemical_list: C039984:Bretschneider cardioplegic solution; D008353:Mannitol; D011343:Procaine; D011189:Potassium Chloride; D005947:Glucose