Platelet-activating factor receptor antagonism improves cerebral recovery after circulatory arrest

Background. The aim of this study was to determine the effects of antagonis m of platelet-activating factor receptors on cerebral recovery after deep h ypothermic circulatory arrest (DHCA). Methods. Fourteen I-week-old piglets were randomly assigned to either place bo (n = 7), or 10 mg/kg intravenous ginkgolide B (BN52021), a naturally occ urring platelet-activating factor receptor antagonist. All piglets had card iopulmonary bypass, cooling to 18 degrees C, 60 minutes of circulatory arre st followed by 60 minutes of reperfusion and rewarming. Global and regional cerebral blood flow, cerebral oxygen metabolism and renal blood flow were determined at baseline before DHCA and after 60 minutes of reperfusion. Results. Blood flow was significantly reduced in all regions of the brain ( p < 0.001) and the kidneys (p = 0.02) after DHCA in control animals. Cerebr al oxygen metabolism was also significantly reduced after DHCA to 59.2% +/- 3.2% of the pre-DHCA value (p = 0.0003). In the ginkgolide B group, recove ry of global cerebral blood flow to 60.4% +/- 2.8% of pre-DHCA level and of global cerebral oxygen metabolism to 77.1% +/- 5.8% of pre-DHCA value were significantly higher than the recovery in the control group (p < 0.02). Re gional recovery of cerebral blood flow and oxygen metabolism in the gingkol ide B group was greatest in the cerebellum and brainstem. Renal blood flow did not decrease significantly after DHCA in the gingkolide B group (p = 0. 23). Conclusions. These results suggest that production of platelet-activating f actor is increased in the brain after DHCA. Platelet-activating factor rece ptor antagonism with ginkgolide B before the circulatory arrest period can significantly improve recovery of cerebral blood flow and oxygen metabolism and renal blood flow after DHCA. (C) 1999 by The Society of Thoracic Surge ons.