Effect of Intraoperative Fluid Restriction on Postoperative Outcomes in Video-assisted Thoracic Surgery (VATS)

Working hypothesis and aims: The aim of this study is to investigate the effect of restrictive versus standard intraoperative fluid regimen on cardiopulmonary mordibity and mortality after VATS for lung resection. Our study hypothesis is that restrictive intraoperative fluid administration in patients undergoing VATS, will lead to better outcomes compared to a liberal fluid regimen. Methods: After obtaining informed consent, patients will be randomly assigned to one of two groups-liberal-protocol group (LG) or restricted-protocol group (RG). Anesthetic and surgical management will be performed similarly and according to standards for both groups, with one exception: patients in the RG group will receive 2 ml/kg•hr whereas patients in the RL group will receive 8 ml/kg•hr of Ringer Lactate (RL) solution throughout the intraoperative period. Hemodynamic changes during this period will be treated pharmacologically unless indicated otherwise. Blood loss, in both groups, will be replaced with RL solution in a 3:1 volume replacement, and blood and/or blood products will be transfused when required. Postoperatively, pain and fluid management will be standardized for both groups, according to departmental routines. Patient assessment will be performed by a blinded assessor. The primary endpoints of the study will combine: the incidence of post-operative complications (pulmonary, cardiovascular, others), re-intubations, and readmitions to the ICU during primary hospitalization; number of patients readmitted to the hospital within 30 days of surgery. The secondary endpoints will include length of hospital stay, differences in hematocrit, urea, creatinine concentrations and oxygen saturation immediately postoperatively, in the first and third postoperative days and with discharge, and the number of patients receiving transfusion of blood and blood products; time to extubation, time to sit/stand/walk/eat/drink (recovery data).