Comparison of dobutamine under different fluids resuscitation for shock induced by intestinal ischemia/reperfusion injury

Objective To compare the effects of dobutamine under different fluids resuscitation for shock induced by intestinal ischemia/reperfusion (I/R) injury in rabbits. Methods Thirtytwo anesthetized rabbits were randomized into four groups of eight animals each. The groups were followed as: ①lactated Ringer's solution(LRS) resuscitation; ②LRS+hydroxyethyl starch solution(HES) resuscitation; ③LRS resuscitation+dobutamine treatment; ④LRS+HES resuscitation+dobutamine treatment. All these rabbits underwent the intestinal I/R injury developed by occluding superior mesenteric artery (SMA) with a noncrushing vascular clamp for 60 minutes and then loosing the clamp for 300 minutes. The fluid resuscitation and drug treatment began at the same time of reperfusion. Hemodynamic parameters including mean artery pressure (MAP), heart rate (HR), aortic velocity (AoV, as cardiac output) and SMA blood flow (Qsma) were measured. Tissue oxygenation was assessed indirectly by measuring the tonometric parameters of the gut, including difference between partial pressure of carbon dioxide in intestinal intramucosal and partial pressure of carbon dioxide in arterial blood (PtaCO 2 gap), intestinal intramucosal pH (pHi), arterial blood lactate acid concentration and oxygen delivery (DO 2). Results HR, AoV and Qsma as measured in two dobutamine groups were significantly higher in values than LRS and LRS+HES groups (all P 0 05). But MAP as measured in two dobutamine groups were significantly higher in values than only LRS ( P 0 05), and in LRS+HES resuscitation+dobutamine treatment group was also significantly higher in values than LRS resuscitation+dobutamine treatment group ( P 0 05). Dobutamine in LRS resuscitation+dobutamine treatment and LRS+HES resuscitation+dobutamine treatment group could greatly decrease lactate and PtaCO 2 gap, significantly improve pHi and DO 2 compared with other two resuscitation groups (all P 0 05). Dobutamine in LRS+HES resuscitation+dobutamine treatment group could also greatly decrease lactate and PtaCO 2 gap, significantly improve pHi compared with LRS resuscitation+dobutamine treatment group (all P 0 05). Conclusion Dobutamine could improve hemodynamic parameters and tissue oxygenation in shock induced by intestinal I/R injury in rabbits, being better used under the LRS+HES resuscitation.