The effect of low flow anesthesia with sevoflurane on oxidative status: A prospective, randomized study.

OBJECTIVES: To assess the impact of low-flow, mid-flow, and high-flow sevoflurane anesthesia on the oxidative state by measuring thiol/disulfide levels in patients undergoing surgery. METHODS: The study included 99 patients randomly assigned to 3 groups. In the low-flow anesthesia group, the fresh gas flow was diminished to 1 L.min-1 for anesthesia maintenance after 6 L.min-1 was administered for the first 10 minutes. In the mid-flow anesthesia group, fresh gas flow was applied as 2 L.min-1. In the high-flow anesthesia group, the fresh gas flow was administered as 4 L.min-1 throughout the operation. Blood samples were obtained before induction, at the 60th minute after induction, and at 2 hours postoperatively. Native thiol, total thiol, disulfide analyzed and disulfide/native thiol percentage, disulfide/total thiol percentage, and native thiol/total thiol percentage were calculated. RESULTS: Disulfide values in mid-flow and low-flow anesthesia were significantly lower at the 60th minute after induction compared to the high-flow anesthesia group. In the group evaluations, intraoperative native thiol levels in the high-flow group were found to be substantialy lower than preoperative values. CONCLUSION: It was sighted that low-flow anesthesia with sevoflurane prohibited oxidative damage. It was concluded that low flow anesthesia can be utilized safely in this respect.

Peri-operative blood transfusion in elective major surgery: incidence, indications and outcome - an observational multicentre study.

BACKGROUND: Patients' demographic and epidemiological characteristics, local variations in clinicians' knowledge and experience and types of surgery can influence peri-operative transfusion practices. Sharing data on transfusion practices and recipients may improve patients' care and implementation of Patient Blood Management (PBM). MATERIALS AND METHODS: This was a multicentre, prospective, observational, cross-sectional study that included 61 centres. Clinical and transfusion data of patients undergoing major elective surgery were collected; transfusion predictors and patients' outcomes were analysed. RESULTS: Of 6,121 patients, 1,579 (25.8%) received a peri-operative transfusion. A total of 5,812 blood components were transfused: red blood cells (RBC), fresh-frozen plasma and platelets in 1,425 (23.3%), 762 (12.4%) and 88 (1.4%) cases, respectively). Pre-operative anaemia was identified in 2,019 (33%) patients. Half of the RBC units were used by patients in the age group 45-69 years. Specific procedures with the highest RBC use were coronary artery bypass grafting (16.9% of all units) and hip arthroplasty (14.9%). Low haemoglobin concentration was the most common indication for intra-operative RBC transfusion (57%) and plasma and platelet transfusions were mostly initiated for acute bleeding (61.3% and 61.1%, respectively). The RBC transfusion rate in study centres varied from 2% to 72%. RBC transfusion was inappropriate in 99% (n=150/151) of pre-operative, 23% (n=211/926) of intra-operative and 43% (n=308/716) of post-operative RBC transfusion episodes. Pre-operative haemoglobin, increased blood loss, open surgery and duration of surgery were the main independent predictors of intra-operative RBC transfusion. Low pre-operative haemoglobin concentration was independently associated with post-operative pulmonary complications. CONCLUSIONS: These findings identified areas for improvement in peri-operative transfusion practice and PBM implementation in Turkey.