The Influences Of Ringer’s Acetate Infusion On Acid-base And Electrolyte In Patients Undergoing Brain Tumor Resection

Objective: To observe the effects of normal saline and Ringer’s acetate infusionon acid-base, electrolytes．Methods: Sixty ASA class II to Ⅲpatients undergoing brain tumor resectionwere randomized into two groups of normal saline (group NS, n=30) and Ringer’sacetate (group SA, n=30)．A preload of8ml/kg normal saline or Ringer’s acetate wasinfused in15min in each patient, which was followed by20ml/kg6%HES130/0.4after induction. Then normal saline or Ringer’s acetate was given afterwards. Bloodgas analysis was carried before infusion(T1)，at the end of first infusion(T2),3hafter completion of first fluid infusion(T3) and5h after completion of first fluidinfusion(T4). Observe and record the plasma K+, Na+, CI-, Ca2+, Mg2+, pH, Lac,HCO3-, and total amount of infusion, blood loss and urine.Midazolam2mg，cisatracurium0.15mg/kg，fentanyl3μg/kg，propofol2mg/kg weregiven for the anesthesia induction. Mechanical ventilation was given after intubation.Tidal volume8ml/kg, fresh gas flow2L/min and breathing rate12times/min were setto keep the end tidal CO2between30mmHg and40mmHg. Anesthesia wasmaintained by propofol (5~7mg/kg/h) and remifentanil (3~12μg/kg/h) intravenously,supplemental cisatracurium was given intermittently. Special situation handling: ifheart rate <50bpm, intravenous atropine will be administered. When blood pressurerises or falls over20%of the baseline, vasoactive drug will be intravenouslyadministered or the infusion rate will be adjusted. SPSS17.0was used in dataprocessing. Intra-group comparison was performed with paired t test and comparisonbetween groups was performed with independent sample t-test. Counting data wasexpressed by chi-square test and measurement date was expressed bymean±standard(x±s)deviation. P<0.05is considered as statistical significance. Results: There was no significant difference in general information (gender, age,weight) between two groups. At T1, the two groups showed no significantdifference.Compared with those before，serum concentration of Lac and Cl-were increased andHCO3-and pH were decreased after infusion of normal saline in group NS, whichwere not significantly changed in group SA(P<0.05).Conclusion: Compared with normal saline, the infusion of larger amount ofRinger’s acetate could decrease the incidence of hyperchloremia and metabolicacidosis in patient under brain tumor resection.