Fluid Therapy and Glycocalyx Shedding During Moderate Surgery

Goal-directed fluid therapy is one of the most accepted strategies in intraoperative fluid therapy, although potential fluid overload is a possible drawback. Fluid overload has recently been shown to cause damage to the glycocalyx and to increase extravasation of fluids into the interstitial space. This study aims to determine whether liberal fluid administration during moderate surgery results in impairment to the endothelial glycocalyx and causes edema. Participants will be randomized to receive either a liberal or restrictive fluid protocol with vasopressor support. The investigators will measure interstitial edema by clinical signs, pulmonary congestion by ultrasound, and extracellular water by bioimpedance. Impairment of glycocalyx will be estimated by measuring blood levels of shedding markers. In addition, wound healing and early postoperative outcome will be estimated by POMS.