Clinical Study Evidence for Negative Effects of Elevated Intra-Abdominal Pressure on Pulmonary Mechanics and Oxidative Stress I. DavarcJ, 1 M. KarcJoLlu, 1 K. Tuzcu, 1 K. EnanoLlu, 1 T. D. Yetim, 2 S. Motor, 3 K. T. UlutaG, 3 and R. Yüksel 3 1 Department of Anesthesiology, Faculty of Medicine, Mustafa Kemal University, Hatay, Turkey 2 Department of Toracic Surgery, Faculty of Medicine, Mustafa Kemal University, Hatay, Turkey 3 Department of Biochemistry, Faculty of Medicine, Mustafa Kemal University, Hatay, Turkey Correspondence should be addressed to I. Davarcı; isildavarci@gmail.com Received 21 July 2014; Accepted 29 December 2014 Academic Editor: Daiana Avila Copyright © 2015 I. Davarcı et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Objective. To compare the efects of pneumoperitoneum on lung mechanics, end-tidal CO 2 (ETCO 2 ), arterial blood gases (ABG), and oxidative stress markers in blood and bronchoalveolar lavage fuid (BALF) during laparoscopic cholecystectomy (LC) by using lung-protective ventilation strategy. Materials and Methods. Forty-six patients undergoing LC and abdominal wall hernia (AWH) surgery were assigned into 2 groups. Measurements and blood samples were obtained before, during pneumoperitoneum, and at the end of surgery. BALF samples were obtained afer anesthesia induction and at the end of surgery. Results. Peak inspiratory pressure, ETCO 2 , and pCO 2 values at the 30th minute were signifcantly increased, while there was a signifcant decrease in dynamic lung compliance, pH, and pO 2 values in LC group. In BALF samples, total oxidant status (TOS), arylesterase, paraoxonase, and malondialdehyde levels were signifcantly increased; the glutathione peroxidase levels were signifcantly decreased in LC group. Te serum levels of TOS and paraoxonase were signifcantly higher at the end of surgery in LC group. In addition, arylesterase level in the 30th minute was increased compared to baseline. Serum paraoxonase level at the end of surgery was signifcantly increased when compared to AWH group. Conclusions. Our study showed negative efects of pneumoperitoneum in both lung and systemic levels despite lung-protective ventilation strategy. 1. Introduction Te increasing number of indications of laparoscopic surgery, which is the gold standard approach in several diagnostic and therapeutic procedures, means that anesthesiologists need to have a better understanding of the physiological efects and potential complications of pneumoperitoneum [1]. Laparoscopic surgery, a minimal invasive technique, has substantial efects on the hemodynamic and respiratory sys- tem, even in healthy individuals, although it has many advan- tages compared to conventional open surgical techniques. Tese pathophysiological efects result in an increased risk of perioperative and postoperative complications in elderly patients with impaired cardiac and pulmonary functions [2, 3]. During laparoscopy, increasing intra-abdominal pressure (IAP) with abdominal CO 2 insufation causes ischemia through splanchnic vasoconstriction and subsequent reper- fusion injury through defation [2]. Moreover, hypercarbia and acidosis can occur because of ventilation-perfusion mis- match caused by impaired gas exchange due to increased IAP or absorption of insufated CO 2 . Hypercarbia and acidosis afect serum oxidative stress markers and lead to altered hemodynamics [4, 5]. In this prospective study, we evaluated the efects of pneumoperitoneum at an IAP level (<12 mmHg) accepted to be clinically safe on lung mechanics, end-tidal CO 2 (ETCO 2 ), arterial blood gases, and oxidative stress markers in blood and bronchoalveolar lavage fuid (BALF) during laparoscopic Hindawi Publishing Corporation e Scientific World Journal Volume 2015, Article ID 612642, 8 pages http://dx.doi.org/10.1155/2015/612642