Restrictive strategy of intraoperative fluid maintenance during optimization of oxygen delivery decreases major complications after high-risk surgery

Abstract

IntroductionOptimal fluid management is crucial for patients who undergo major and prolonged surgery. Persistent hypovolemia is associated with complications, but fluid overload is also harmful. We evaluated the effects of a restrictive versus conventional strategy of crystalloid administration during goal-directed therapy in high-risk surgical patients.MethodsWe conducted a prospective, randomized, controlled study of high-risk patients undergoing major surgery. For fluid maintenance during surgery, the restrictive group received 4 ml/kg/hour and the conventional group received 12 ml/kg/hour of Ringer's lactate solution. A minimally invasive technique (the LiDCO monitoring system) was used to continuously monitor stroke volume and oxygen delivery index (DO2I) in both groups. Dobutamine was administered as necessary, and fluid challenges were used to test fluid responsiveness to achieve the best possible DO2I during surgery and for 8 hours postoperatively.ResultsEighty-eight patients were included. The patients' median age was 69 years. The conventional treatment group received a significantly greater amount of lactated Ringer's solution (mean ± standard deviation (SD): 4, 335 ± 1, 546 ml) than the restrictive group (mean ± SD: 2, 301 ± 1, 064 ml) (P < 0.001). Temporal patterns of DO2I were similar between the two groups. The restrictive group had a 52% lower rate of major postoperative complications than the conventional group (20.0% vs 41.9%, relative risk = 0.48, 95% confidence interval = 0.24 to 0.94; P = 0.046).ConclusionsA restrictive strategy of fluid maintenance during optimization of oxygen delivery reduces major complications in older patients with coexistent pathologies who undergo major surgery.Trial registrationISRCTN: ISRCTN94984995

Colloids versus crystalloids in objective-guided fluid therapy, systematic review and meta-analysis. Too early or too late to draw conclusions

“…40 The basic premise of the GDFT consists of ensuring an optimal blood volume; the association of restrictive fluid therapy 41 with the identification of optimal preload or of those patients who increased their SV through a volume load (respondent to fluids) implies relative hypovolemia; the quick correction of this problem is essential to ensure correct tissue perfusion. This a priori should be faster with colloids, since, as demonstrated in healthy patients and animal models, the proportion of liquid required to achieve a goal of hemodynamic stabilization is 1:4 42 ; however, this cannot be confirmed by the data obtained in this meta-analysis nor can be demonstrated with recent studies specifically designed to determine it.…”

Clarification of the circulatory patho-physiology of anaesthesia – Implications for high-risk surgical patients

“…The study of Lobo et al [15] utilized a DO 2 goal similar to that of Pearse et al [13] above, for two groups; one with typical crystalloid 'maintenance' iv crystalloid (lactated Ringer's solution, 12 ml kg À1 h À1 ), the other with a considerably lower infusion rate (4 ml kg À1 h À1 ). Optimization of DO 2 I was continued throughout surgery and for the following 8 h. Both groups showed a reduced incidence of complications relative to earlier studies on a similar group of patients [16].…”

“…Fluid overload has, however, been shown to be a real concern [14]. The study of Lobo et al [15] has addressed the problem, in particular, with regard to 'maintenance' intravenous (iv) crystalloid. It is important to avoid lumping crystalloid and colloid together simply as fluid, since crystalloid adds to all compartments, colloid principally, at least initially, to the circulatory volume.…”

Nonventilatory strategies to prevent postoperative pulmonary complications

“…Clinical data on the effect of perioperative fluid management on the risk for PPCs during major abdominal surgery are extremely heterogeneous. In two recent prospective investigations a restrictive fluid management strategy was associated with a reduction in the overall complication rate, but the rate of PPCs did not differ among groups [75,76]. In a retrospective analysis of a large database, Blum et al [24 && ] identified a higher amount of intraoperative crystalloid infusion as a risk factor for the development of postoperative ARDS.…”