Perioperative goal-directed therapy with uncalibrated pulse contour methods: impact on fluid management and postoperative outcome.

Previous meta-analyses suggest that perioperative goal-directed therapy (GDT) is useful to decrease postoperative morbidity. Most GDT studies analysed were done with pulmonary artery catheters, oesophageal Doppler and calibrated pulse contour methods. Uncalibrated pulse contour (uPC) techniques are an appealing alternative but their accuracy has been questioned. The effects of GDT on fluid management (volumes and volume variability) remain unclear. We performed a meta-analysis of randomized controlled trials investigating the effects of GDT with uPC methods on postoperative outcome. The primary endpoint was postoperative morbidity. Fluid volumes and fluid volume variability (standard deviation/mean) over the GDT period were also studied. Nineteen studies met the inclusion criteria (2159 patients). Postoperative morbidity was reduced with GDT (OR 0.46, 95% CI 0.30-0.70, P<0.001). The volume of colloids was higher [weighted mean difference (WMD) +345 ml, 95% CI 148-541 ml, P<0.001] and the volume of crystalloids was lower (WMD -429 ml, 95% CI -634 to -224 ml, P<0.01) in the GDT group than in the control group. However, the total volume of fluid (WMD -220 ml, 95% CI -590 to 150 ml, P=0.25) and the variability of fluid volume (34% vs 33%, P=0.98) were not affected by GDT. The use of GDT with uPC techniques was associated with a decrease in postoperative morbidity. It was not associated with an increase in total fluid volume nor with a decrease in fluid volume variability.