title: Electrical Impedance Tomography-guided PEEP Titration in Patients Undergoing Laparoscopic Abdominal Surgery.
abstract: The aim of the study is to utilize electrical impedance tomography (EIT) to guide positive end-expiratory pressure (PEEP) and to optimize oxygenation in patients undergoing laparoscopic abdominal surgery.Fifty patients were randomly assigned to the control (C) group and the EIT (E) group (n = 25 each). We set the fraction of inspired oxygen (FiO2) at 0.30. The PEEP was titrated and increased in a 2-cm H2O stepwise manner, from 6 to 14 cm H2O. Hemodynamic variables, respiratory mechanics, EIT images, analysis of blood gas, and regional cerebral oxygen saturation were recorded. The postoperative pulmonary complications within the first 5 days were also observed.We chose 10 cm H2O and 8 cm H2O as the "ideal" PEEP for the C and the E groups, respectively. EIT-guided PEEP titration led to a more dorsal shift of ventilation. The PaO2/FiO2 ratio in the E group was superior to that in the C group in the pneumoperitoneum period, though the difference was not significant (330 ± 10 vs 305.56 ± 4 mm Hg; P = 0.09). The C group patients experienced 8.7% postoperative pulmonary complications versus 5.3% among the E group patients (relative risk 1.27, 95% confidence interval 0.31-5.3, P = 0.75).Electrical impedance tomography represents a new promising technique that could enable anesthesiologists to assess regional ventilation of the lungs and optimize global oxygenation for patients undergoing laparoscopic abdominal surgery.
authors.affiliation: From the Department of Anesthesiology (XH, JJ, YL, HX, SZ, XS, HY), Changzheng Hospital, the Second Military Medical University, Shanghai; The Seventh Hospital of People's Liberation Army (SY), Xichuan Linxia, Gansu; and Department of Anesthesiology (XS), Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Xingying
authors.initials: X
authors.lastname: He
authors.forename: Jingjing
authors.initials: J
authors.lastname: Jiang
authors.forename: Yuli
authors.initials: Y
authors.lastname: Liu
authors.forename: Haitao
authors.initials: H
authors.lastname: Xu
authors.forename: Shuangqiong
authors.initials: S
authors.lastname: Zhou
authors.forename: Shibo
authors.initials: S
authors.lastname: Yang
authors.forename: Xueyin
authors.initials: X
authors.lastname: Shi
authors.forename: Hongbin
authors.initials: H
authors.lastname: Yuan
mesh_terms: D000005:Abdomen / Q000601:surgery*; D017097:Electric Impedance; D005260:Female; D006801:Humans; D010535:Laparoscopy; D008297:Male; D008875:Middle Aged; D011175:Positive-Pressure Respiration / Q000379:methods*; D011446:Prospective Studies; D014054:Tomography / Q000379:methods*