title: Protective mechanical ventilation during general anesthesia for open abdominal surgery improves postoperative pulmonary function.
abstract: BACKGROUND
  The impact of intraoperative ventilation on postoperative pulmonary complications is not defined. The authors aimed at determining the effectiveness of protective mechanical ventilation during open abdominal surgery on a modified Clinical Pulmonary Infection Score as primary outcome and postoperative pulmonary function.
  
  
  METHODS
  Prospective randomized, open-label, clinical trial performed in 56 patients scheduled to undergo elective open abdominal surgery lasting more than 2 h. Patients were assigned by envelopes to mechanical ventilation with tidal volume of 9 ml/kg ideal body weight and zero-positive end-expiratory pressure (standard ventilation strategy) or tidal volumes of 7 ml/kg ideal body weight, 10 cm H2O positive end-expiratory pressure, and recruitment maneuvers (protective ventilation strategy). Modified Clinical Pulmonary Infection Score, gas exchange, and pulmonary functional tests were measured preoperatively, as well as at days 1, 3, and 5 after surgery.
  
  
  RESULTS
  Patients ventilated protectively showed better pulmonary functional tests up to day 5, fewer alterations on chest x-ray up to day 3 and higher arterial oxygenation in air at days 1, 3, and 5 (mmHg; mean ± SD): 77.1 ± 13.0 versus 64.9 ± 11.3 (P = 0.0006), 80.5 ± 10.1 versus 69.7 ± 9.3 (P = 0.0002), and 82.1 ± 10.7 versus 78.5 ± 21.7 (P = 0.44) respectively. The modified Clinical Pulmonary Infection Score was lower in the protective ventilation strategy at days 1 and 3. The percentage of patients in hospital at day 28 after surgery was not different between groups (7 vs. 15% respectively, P = 0.42).
  
  
  CONCLUSIONS
  A protective ventilation strategy during abdominal surgery lasting more than 2 h improved respiratory function and reduced the modified Clinical Pulmonary Infection Score without affecting length of hospital stay.
authors.affiliation: Department of Ambient, Health and Safety, University of Insubria, Varese, Italy. paolo.severgnini@uninsubria.it
authors.forename: Paolo
authors.initials: P
authors.lastname: Severgnini
authors.forename: Gabriele
authors.initials: G
authors.lastname: Selmo
authors.forename: Christian
authors.initials: C
authors.lastname: Lanza
authors.forename: Alessandro
authors.initials: A
authors.lastname: Chiesa
authors.forename: Alice
authors.initials: A
authors.lastname: Frigerio
authors.forename: Alessandro
authors.initials: A
authors.lastname: Bacuzzi
authors.forename: Gianlorenzo
authors.initials: G
authors.lastname: Dionigi
authors.forename: Raffaele
authors.initials: R
authors.lastname: Novario
authors.forename: Cesare
authors.initials: C
authors.lastname: Gregoretti
authors.forename: Marcelo Gama
authors.initials: MG
authors.lastname: de Abreu
authors.forename: Marcus J
authors.initials: MJ
authors.lastname: Schultz
authors.forename: Samir
authors.initials: S
authors.lastname: Jaber
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Futier
authors.forename: Maurizio
authors.initials: M
authors.lastname: Chiaranda
authors.forename: Paolo
authors.initials: P
authors.lastname: Pelosi
mesh_terms: D000005:Abdomen / Q000601:surgery*; D000368:Aged; D000768:Anesthesia, General / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007430:Intraoperative Care / Q000379:methods*; D008171:Lung Diseases / Q000517:prevention & control*; D008297:Male; D011175:Positive-Pressure Respiration / Q000379:methods; D011183:Postoperative Complications / Q000517:prevention & control*; D011184:Postoperative Period; D011446:Prospective Studies; D012121:Respiration, Artificial / Q000379:methods*; D012129:Respiratory Function Tests / Q000379:methods / Q000706:statistics & numerical data; D013990:Tidal Volume; D016896:Treatment Outcome