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

Abstract

Introduction: Optimal 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.

Methods: We 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.

Results: Eighty-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).

Conclusions: A restrictive strategy of fluid maintenance during optimization of oxygen delivery reduces major complications in older patients with coexistent pathologies who undergo major surgery.

Trial registration: ISRCTN: ISRCTN94984995.

Figure 1

Algorithm of treatment. Delta-PP = change in arterial pulse pressure variation; DO₂ = oxygen delivery; Hb = hemoglobin; SatO₂ = oxygen saturation; SV = stroke volume.

Figure 2

Temporal patterns. Temporal patterns of oxygen delivery (DO₂) during surgery and postoperatively for the restrictive group (black triangles) and the conventional group (black squares). The results are presented as means and standard errors of the mean. 0, preoperative; 1, 30 minutes intraoperatively (IO); 2, 60 minutes IO; 3, 120 minutes IO; 4, 180 minutes IO; 5, 240 minutes IO; 6, 300 minutes IO; 7, 360 minutes IO; 8, 420 minutes IO; 9, 480 minutes IO; 10, ICU admission; 11, 1 hour postoperatively (PO); 12, 2 hours PO; 13, 3 hours PO; 14, 4 hours PO; 15, 5 hours PO; 16, 6 hours PO; 17, 7 hours PO; 18, 8 hours PO. Treatment × time interaction; P < 0.0001.