Effect Of Goal-Directed Fluid Therapy On The Elderly Patients Outcome Undergoing Lumbar Decompressive Surgery

Objective:Goal-directed therapy has been proposed as a method to improve perfusion of tissue and organ and reduce complications and mortality. The goal-directed therapy (GDT) is used to manage the fluid therapy during operation. GDT is a term that determines the optimal dose of fluid, cardiac inotropes and vasopressors through monitoring the variation of hemodynamic to optimize cardiac output (CO) and oxygen delivery (DO2) to the tissues. It can prevent condition of hypoperfusion and hyperperfusion. This therapy is performed to improve the results in terms of survival and quality of life and reduce the incidence of postoperative complications. Our object is to evaluate the effect of goal-directed fluid therapy on serum lactate acid, perfusion and outcomes following lumbar decompressive surgery of elderly patients.Method:Patients of the Department of orthopedics of PUMC receiving selective lumbar decompression surgery, were enrolled in this prospective and randomized trial from 2015 Dec to 2016 Apr. Patients were allocated to either anesthesiologist-directed fluid therapy or goal-directed fluid therapy which improves perfusion using colloid bolus to optimize stroke volume. The primary outcomes were level of lactate acid variation in 7 specific time spot:24h before surgery(T0), after induction(T1), before decompressive(T2), after decompressive(T3), ending of surgery(T4), time leaving the PACU(T5),24h after surgery(T6), and the incidence of postoperative complications. The secondary outcomes were the volume of fluids, the gastrointestinal functional recovery and the duration of hospital stay.Result:(1)66 patients were enrolled in this study(GDT group 33, control group 33). There were no significant differences in age, gender, BMI, history and preoperative laboratory examination. (2) The variation and difference of the level of lactate acid:in C group the lactate acid increased during the surgery, but in G group the level of lactate was stable and stayed within normal level. In T0、T1、T2、T3、T4、T6 there were no significant differences in lactate. As for T5, the level of lactate acid in group C is significantly higher than group G. (3) The variation of hemodynamics during the surgery:as for MAP and HR, there were no significant differences in two group at T1、T2、T3、T4. The monitor parameter SVV of C group is higher than that of group G, with statistically significant difference. In T4, the CO of C group is significant lower than that of G group. (4) The differences of volume of fluids during the surgery:patients randomized to the G group were given a greater volume of intravenous fluids during intraoperative period. Although the patients received ephedrine between two groups were in no differences, the use of ephedrine for each patient in C group is much higher than G group, with statistically significant difference. (5) The impact in GI function and outcomes:as for gastrointestinal function, there were no significant differences in time of firstly postoperative flatus passage, defecation, drinking, eating and hospital length of stay. But in C group, there were 13 patients defecating by using glycerin enema, significant higher than in G group. Besides there were an increased number of complications in the C group. The incidence of postoperative complications of control group is higher than that of GDT group.Conclusion:(1) Goal-directed fluid therapy during lumbar decompressive surgery under general anaesthesia results in a significant increasing in volume of fluids and reduction in level of lactate acid, improving the perfusion of tissues and organs. (2) Goal-directed fluid therapy enhanced GI functional recovery, lower incidence of postoperative organ complications, and enhanced the recovery after surgery.