中低温停循环经下腔静脉逆灌对猪肠系膜微循环的影响

目的 观察中低温下半身停循环时经下腔静脉(IVC)逆行灌注方法对猪肠系膜微循环变化的影响.方法 选择健康小型猪20只,随机分为A、B两组(n=10).两组均在体外循环(ECC)下肛温降到28℃时停循环60 min,同时经右无名动脉行顺灌脑保护.A组单纯下半身停循环.B组停循环同时联合经IVC逆灌行腹腔脏器保护,灌注压力...

Changes of mesentery microcirculation in pigs with retrograde perfusion via inferior vena cava during moderate hypothermic lower body circulatory arrest

OBJECTIVE To investigate the changes of mesentery microvessels diameter and micro-blood-flow velocity in pigs with retrograde perfusion via inferior vena cava(IVC) during moderate hypothermic lower body circulatory arrest.METHODS Twenty healthy pigs were randomly divided into two groups(n=10).Hypothermic circulatory arrest(HCA) combined with selective antegrade cerebral perfusion was implemented when rectal temperature was cooled to 28℃ in both groups.Group A was under moderate hypothermic lower body circulatory arrest.Group B was under moderate hypothermic lower body circulatory arrest combined with retrograde perfusion via IVC.Total HCA time was 60 minutes.Retrograde perfusion pressure was 20 mm Hg at the first 20 minutes,25 mm Hg at the middle 20 minutes and 30 mm Hg at the last 20 minutes.Microcirculation microscope image analysis system BI-2000 was used to record the changes of diameter and velocity of the mesenteric microvessels.RESULTS 1.There was no significant difference in diameter and blood flow velocity of the mesenteric microvessels between these two groups at parallel circulation and before extracorporeal circulation(ECC).2.Compared with group A,diameter and blood flow velocity of microvessels in group B were significantly increased after retrograde perfusion via IVC(P<0.05).3.Diameter and blood flow velocity of microvessels were significantly increased when perfusion pressure was raised from 20 to 25 mm Hg(P<0.01),but there was no significant difference of these parameters when perfusion pressure was raised from 25 to 30 mm Hg(P>0.05).CONCLUSION The function of mesenteric microcirculation can be improved with retrograde perfusion via IVC.The optimal pressure is 25 mm Hg.