Abstract 291: Intestinal Microcirculatory Alterations in a Rat Model of Cardiac Arrest and Resuscitation

Abstract

Introduction: Abnormalities in intestinal microvascular blood flow are of increasing interest during the post-resuscitation phase following cardiac arrest because of the critical role attributed to the intestine in the pathogenesis of systemic inflammatory response, which potentially further aggravate post-resuscitation myocardial and cerebral dysfunction. The present study investigated post-resuscitation mesenteric microcirculatory dysfunctions in a rat model of cardiac arrest and resuscitation. Methods: Eight Sprague-Dawley rats were divided into two groups: 1) VF8+PC8 group: 8 mins of untreated VF followed by 8 mins of CPR and defibrillation (n=5); 2) sham control: animals only underwent surgical procedure (n=3). A laparotomy was performed to expose a segment of the jejunum. Twenty-second clips of the mesenteric microcirculation were captured with the sidestream dark field (SDF) video microscope at three locations at baseline and at 1, 2, 4, 6, 8 hours after the return of spontaneous circulation (ROSC). Mesenteric microcirculatory blood flow was quantified off-line by determining the microcirculatory flow index (MFI). Results: MFIs were significantly reduced 1 hour after ROSC and gradually recovered until it reached a peak at the 6th hour. This was followed by a remarkable decrease at the 8th hour. Compared with control group, MFIs reductions in the VF8+PC8 group were statistically significant (p<0.01) at all time points except for 6 hours after ROSC. Conclusion: There was a significant reduction in mesenteric microcirculatory blood flow following successful resuscitation from cardiac arrest.