Effect Of Controlled Low Central Venous Pressure On Human Intestinal Oxygen Metabolism

Objective:To study the effect of low central venous pressure(LCVP)on human haemodynamics and intestinal oxygen metabolism by observing the changes of haemodynamics,blood gas analysis and the concentration of lactic acid of intestine on patients of hepatic resection.Method:Thirty ASAⅠ～Ⅱpatients with liver tumor scheduled hepatic resection operation under general anesthesia were divided into three groups with ten patients of each:LCVP and controlled transfusion(groupâ… );LCVP and conventional transfusion(groupâ…¡);control group(groupâ…¢).CVP was controlled under 5 cmH₂O by limiting the infusion of fluid or combining it with low-dose nitroglycerin.In every group,SBP,DBP,MAP,ECG,HR were monitored and recorded,the volume of blood loss,transfusion and urinary and the time of LCVP and surgery were recorded.At three different time point: before induction(T₁),before LCVP(T₂),the last moment of LCVP(T₃)or the corresponding time point,the blood samples were drawn from radial artery and superior mesenteric vein,the blood gas analysis and the concentration of lactic acid were evaluated,and CaO₂,CvmO₂,ERO₂,D_VM-ABL were calculated.Results:1.The effect of LCVP on haemodynamics:Compared T₂,SBP, DBP,MAP and CVP of gropeâ… and gropeâ…¡decreased dramatically(P＜0.05) and HR of them increased(P＜0.05)at T₃,but all of them were in normal scope. SBP,DBP,MAP,CVP and HR of groupâ…¢had no conspicuous change(P＞ 0.05).2.The effect of LCVP on intestinal oxygen metabolism:Both of the gropeâ… and gropeâ…¡were conformed to the standard of LCVP.Compared T₂,CaO₂. and CvmO₂ of three groups decreased dramatically(P＜0.05),ABL and VMBL of three groups had conspicuous increasing(P＜0.05).ERO₂ and VM-ADL had no dramatical change at T₃.CaO₂,CvmO₂,ABL,VMBL,ERO₂ and VM-ADL of groupâ… had no conspicuous difference compared with groupâ…¡in each time point(P＞0.05).Conclusion:This study suggests that low central venous pressure has no significant adverse effect on human haemodynamics and intestinal oxygen metabolism.The volume of fluid infusion do not affect haemodynamics and intestinal oxygen metabolism markedly during LCVP,the LCVP method via limiting the infusion of fluid is safe for the balance of intestinal oxygen metabolism.