The Effects Of Intravenous Fluid Restriction On Hemorheology, Cardiac Troponin â…  And S100B In Elderly Paitients Undergoing Intraabdominal Surgery

Objective To investigate the effects of intravenous fluid restriction on hemorheology, cTnI and S100B in old patients undergoing intraabdominal surgery.Method Sixty patients older than 60 years with an American Society of Anesthesiologists physical status of I–III who were undergoing elective intraabdominal surgery. Patients were randomly assigned to receive a standard group (n=30) or a restricted group (n=30). In the standard group, fluid management according to Miller's Anesthesia's opinion: Rate of fluid administration=CVE+Deficit+Maintenance+Loss+Third space. In the restricted group, patients were administered half of deficit before the surgery, then the initial infusion rate is 4 ml/kg/h, the CVP was measured every 15 minutes and maintained it at 5~7 cmH2O, without limiting the total amount of transfusion. In both groups crystals and colloid's ratio is 2:1, the crystal choose to use the lactated Ringer's solution, and the colloid choose the HS130/0.4 (Voluven). We are monitoring ECG, BP, SpO2, CVP, urine output and fluid amount at the whole process of anesthesia. In both groups, the venous blood sample were taken for determination of hemorheological parameters and the serum concentrations of cTnI and S100B protein before anesthesia (T1), 2 hours after skin incision(T2), 30 mins after extubation(T3), 24 hours after the operation (T4). The postoperative morbidity, recovery of bowel function and hospital stay was measured after the patients returned to the ward.Results The intraoperative volumes of fluid administered in the restricted group was significantly lower than the standard group (P <0.05); The restricted group's central venous pressure(CVP) is significantly lower than standard group (P <0.05), but still within the normal range; at T2 and T3 the restricted group of hemorheological parameters (the whole-blood viscosity and plasma viscosity, hematocrit) compared with the standard group have significant differences (P<0.05), also the changes are significantly lower than preoperative(P<0.05). At T2 the serum concentrations of cTnI and S100B in restricted group have no significant differences with standard group (P>0.05), and there is no significant differences with preoperative(P>0.05). The number of patients with postoperative complications in restricted group was lower than the standard group's. Patients in restricted group passed flatus (P<0.05) and feces (P<0.05) were significantly earlier, and their postoperative hospital stay was significantly shorter(P<0.05) .Conclusion It's safe, feasible and advantageous to use of restrictive fluid management during elderly patients undergoing elective intraabdominal surgery. Because this strategy able to maintain stable haemodynamic variables and hemorheological parameters, provide enough myocardial and cerebral perfusion, reduce postoperative morbidity, and shorten their postoperative hospital stay.