ABSTRACT
Objective To evaluate the effects of different administration routes of lipid emulsion on bupivacaine-induced cardiotoxicity in rats.Methods Forty-eight clean healthy adult male Sprague-Dawley rats,weighing 300-350 g,were divided into 6 groups (n=8 each) using a random number table:Ⅳ infusion of normal saline (NS) group (group VN),Ⅳ infusion of lipid emulsion group (group VL),duodenal infusion of NS group (group DN),duodenal infusion of lipid emulsion group (group DL),intraperitoneal intusion of NS group (group PN) and intraperitoneal infusion of lipid emulsion group (group PL).In VN and VL groups,preheated NS and 20％ lipid emulsion 3 ml · kg-1 · min-1 were infused via the femoral vein for 5 min,respectively,and then 0.75％ bupivacaine was infused at the rate of 2 mg · kg-1 · min-1 until cardiac arrest happened.Preheated NS and 20％ lipid emulsion 15 ml/kg were infused via the duodenum (over 1 min,at a constant rate) in DN and DL groups,respectively,and were intraperitoneally infused in PN and PL groups,respectively,followed by an infusion of 0.2 ml/min for 15 min in DN,DL,PN and PL groups.Then 0.75％ bupivacaine was infused via the left femoral vein at a rate of 2 mg · kg-1 · min-1 until cardiac arrest happened.The time to ventricular arrhythmia,mean arterial pressure (MAP) decreasing to 50％ of the baseline and cardiac arrest was recorded.The amount of bupivacaine consumed was calculated immediately after ventricular arrhythmia occurred (T0),immediately after MAP decreased to 50％ of the baseline (T1) and immediately after occurrence of cardiac arrest (T2).Arterial blood samples were collected at T0-2 for determination of the concentration of bupivacaine in plasma by high-performance liquid chromatography.Results Compared with group VN,the time to ventricular arrhythmia,MAP decreasing to 50％ of the baseline and cardiac arrest was significantly prolonged,and the amount of bupivacaine consumed was increased at T0-2 in group VL (P＜0.01).There was no significant difference in the parameters mentioned above between group DN and group DL,and between group PN and group PL (P＞0.05).Compared with group VL,the time to ventricular arrhythmia,MAP decreasing to 50％ of the baseline and cardiac arrest was significantly shortened,and the amount of bupivacaine consumed was decreased at T0-2 in DL and PL groups (P＜0.01).Compared with group DL,the time to ventricular arrhythmia,MAP decreasing to 50％ of the baseline and cardiac arrest was significantly prolonged,and the amount of bupivaeaine consumed was increased at T0.2 in group PL (P＜0.05).There was no significant difference in the concentration of plasma bupivacaine between six groups (P＞0.05).Conclusion Ⅳ infusion of lipid emulsion can decrease bupivacaine-induced cardiotoxicity when compared with duodenal and intraperitoneal infusion in rats.
ABSTRACT
Objective To compare the accuracy of stroke volume variation (SVV),central venous pressure (CVP) and puhnonary arterial wedge pressure (PAWP) in monitoring the changes in blood volume in the patients undergoing renal transplantation.Methods Sixteen patients with chronic renal failure,of American Society of Anesthesiologists physical status Ⅱ or Ⅲ,aged 18-55 yr,scheduled for elective allograft renal transplantation under general anesthesia,were enrolled in the study.SVV was continuously monitored with the FloTrac/Vigileo monitor,and CVP,PAWP and stroke volume index (SVI) were continuously monitored with the volumetric pulmonary artery catheter during surgery.The parameters of hemodynamics were recorded at 30 min after induction of anesthesia,5 min before renal artery opening,5 and 30 min after renal artery opening,and at the end of surgery.Hydroxyethyl starch 130/0.4 electrolyte solution 6 ml/kg was infused over 15 min via the central venous catheter to perform fluid responsiveness starting from 30 min after induction of anesthesia.Positive fluid responsiveness was defined as the change in SVI ≥ 15％.The relationship between SVV and CVP and between SVV and PAWP was analyzed using the Pearson correlation analysis.The receiver operating characteristic curve for CVP,SVV and PAWP in monitoring the changes in blood volume was drawn,and the area under the curve was calculated.Results Compared with the value at 5 min before renal artery opening,SVV was significantly increased after renal artery opening (P＜0.05),and no significant change was found in CVP and PAWP after renal artery opening (P＞0.05).SVV was negatively correlated with CVP,and r=-0.82 (P＜0.01);SVV was negatively correlated with PAWP,and r=-0.77 (P＜0.01).The area under the curve of SVV in monitoring the changes in blood volume was 0.87,and of CVP and PAWP was 0.69 and 0.66,respectively.Conclusion SVV provides better accuracy than CVP and PAWP in monitoring the changes in blood volume in the patients undergoing renal transplantation.