Abstract
Introduction: Splanchnic hypoperfusion is central to the pathogenesis of acute respiratory dysfunction syndrome (ARDS) and multiple organ dysfunction syndrome (MODS) after hemorrhagic shock (HS), which is a leading cause of morality in patients with severe trauma; however, the underlying mechanism remains unclear. The purpose of this study was to examine whether liposome-encapsulated hemoglobin (LEH) improves oxygen metabolism in rat small intestine after HS. Methods: HS was induced by withdrawing blood, and mean arterial pressure was maintained at 40 mmHg for 30 minutes. Rats were then resuscitated with shed blood+2 × shed blood volume in normal saline or LEH (equivalent volume to shed blood)+2 × shed blood volume in normal saline over 120 minutes. The small intestines were harvested at four different time points: before HS, after HS, and at 40 and 120 minutes of resuscitation. The tissue levels of lactate and alanine (μmol/g) were measured with 1H magnetic resonance spectroscopy. Data are expressed as means ± SD and were compared by means of one-way analysis of variance followed by post hoc analysis using Fisher's protected least significant difference (n=5 in each group). Results: There was no significant difference in hemodynamics between the shed blood and LEH groups. Improvements in intestinal lactate and alanine levels with resuscitation were equivalent in between the shed blood and LEH groups. Conclusion: LEH appears to have a comparable oxygen carrying capacity to blood and may serve as a useful blood substitute.
