Plasma resuscitation improves and restores intestinal microcirculatory physiology following haemorrhagic shock

Abstract Background and Objectives Intestinal ischaemia–reperfusion injury following resuscitated haemorrhagic shock (HS) leads to endothelial and microcirculatory dysfunction and intestinal barrier breakdown. Although vascular smooth muscle machinery remains intact, microvascular vasoconstriction occurs secondary to endothelial cell dysfunction, resulting in further ischaemia and organ injury. Resuscitation with fresh frozen plasma (FFP) improves blood flow, stabilizes the endothelial glycocalyx and alleviates organ injury. We postulate these improvements correlate with decreased tissue CO 2 concentrations, improved microvascular oxygenation and attenuation of intestinal microvascular endothelial dysfunction. Materials and Methods Male Sprague–Dawley rats were randomly assigned to groups ( n = 8/group): (1) sham, (2) HS (40% mean arterial blood pressure [MAP], 60 min) + crystalloid resuscitation (CR) (shed blood saline) and (3) HS + FFP (shed blood + FFP). MAP, heart rate (HR), ileal perfusion, pO 2 and pCO 2 were measured at intervals until 4 h post‐resuscitation (post‐RES). At 4 h post‐RES, the ileum was rinsed in situ with Krebs solution. Topical acetylcholine and then nitroprusside were applied for 10 min each. Serum was obtained, and after euthanasia, tissues were harvested and snap‐frozen in liquid N 2 and stored at −80°C. Results FFP resuscitation resulted in sustained ileal perfusion as well as rapid sustained return to baseline microvascular pO 2 and pCO 2 values when compared to CR ( p < 0.05). Endothelial function was preserved relative to sham in the FFP group but not in the CR group ( p < 0.05). Conclusion FFP‐based resuscitation improves intestinal perfusion immediately following resuscitation, which correlates with improved tissue oxygenation and decreased tissue CO 2 levels. CR resulted in significant damage to endothelial vasodilation response to acetylcholine, while FFP preserved this function.