title: The Effects of Positive Airway Pressure Ventilation during Cardiopulmonary Bypass on Pulmonary Function Following Open Heart Surgery.
abstract: BACKGROUND
  Intrapulmonary shunt as a result of atelectasis following cardiac surgeries is an important and common postoperative complication that results into pulmonary dysfunction typically lasting more than a week following surgery. Different methods have been provided to prevent these complications.
  
  
  OBJECTIVE
  In order to prevent postoperative pulmonary complications, investigation of the effectiveness of continuous positive airway pressure (CPAP) and intermittent mandatory ventilation (IMV) during cardiopulmonary bypass (CPB) in patients undergoing coronary artery bypass grafting (CABG).
  
  
  METHODS
  In this prospective interventional study, 300 patients, candidate for elective CABG (On-Pump), were randomly allocated to 3 groups: A, B, C. Group A (CPAP) patients received CPAP at 10 cm H2O during CPB. Group B (IMV) patients received IMV with a tidal volume of 2 cc/kg and respiratory rate of 15/min and group C (control) patients did not receive any type of ventilation during CPB. Other procedures were similar between groups. Arterial blood samples were taken at 8 moments and arterial blood gas (ABG) analysis were compared between groups. Chest x-rays after CABG were also evaluated with respect to atelectasis.
  
  
  RESULTS
  The demographic data were similar in between three groups. Graft number, pump time and preoperative ABGs were not significantly different. Postoperative PaO2 were significantly higher in the CPAP and IMV groups and (A-a) DO2 were significantly lower in these two groups, compared to the control group.
  
  
  CONCLUSIONS
  In the present study, applying positive airway pressure methods (CPAP or IMV) during CPB was associated with better postoperative ABG measurements and (A-a) DO2.
authors.affiliation: Rajaie Cardiovascular Medical and Research Center, Tehran University of Medical Sciences, Tehran, IR Iran.
authors.forename: Mostafa
authors.initials: M
authors.lastname: Alavi
authors.affiliation: Rajaie Cardiovascular Medical and Research Center, Tehran University of Medical Sciences, Tehran, IR Iran.
authors.forename: Behshid
authors.initials: B
authors.lastname: Pakrooh
authors.affiliation: Heart Valve Disease Research Center, Rajaie Cardiovascular Medical and Research Center, Tehran University of medical sciences, Tehran, IR Iran.
authors.forename: Yalda
authors.initials: Y
authors.lastname: Mirmesdagh
authors.affiliation: Rajaie Cardiovascular Medical and Research Center, Tehran University of Medical Sciences, Tehran, IR Iran.
authors.forename: Hooman
authors.initials: H
authors.lastname: Bakhshandeh
authors.affiliation: Rajaie Cardiovascular Medical and Research Center, Tehran University of Medical Sciences, Tehran, IR Iran.
authors.forename: Touraj
authors.initials: T
authors.lastname: Babaee
authors.affiliation: Heart Valve Disease Research Center, Rajaie Cardiovascular Medical and Research Center, Tehran University of medical sciences, Tehran, IR Iran.
authors.forename: Saeid
authors.initials: S
authors.lastname: Hosseini
authors.affiliation: Rajaie Cardiovascular Medical and Research Center, Tehran University of Medical Sciences, Tehran, IR Iran.
authors.forename: Faranak
authors.initials: F
authors.lastname: Kargar
keywords: Cardiopulmonary Bypass; Continuous Positive Airway Pressure; Coronary Artery Bypass Grafting