title: Off-pump versus on-pump coronary artery bypass surgery and postoperative pulmonary dysfunction.
abstract: OBJECTIVE
  To investigate how off-pump coronary artery bypass grafting (CABG) affects postoperative pulmonary function when compared with on-pump CABG.
  
  
  METHODS
  Prospective clinical study.
  
  
  METHODS
  University-affiliated teaching hospital.
  
  
  METHODS
  Adult patients (n = 39) undergoing elective coronary artery bypass surgery with or without cardiopulmonary bypass.
  
  
  METHODS
  Two groups of patients were compared: 19 consecutive patients undergoing off-pump CABG surgery and 20 consecutive patients undergoing conventional CABG surgery.
  
  
  RESULTS
  Pulmonary function tests (flow volume loops and lung volumes with plethysmography) were done preoperatively and 72 hours postoperatively. Arterial blood gases and PaO2/FIO2 were measured at various stages. Sequential chest x-rays were obtained and evaluated for pleural changes, pulmonary edema, and atelectasis. In both groups, PaO2/FIO2 ratios decreased progressively throughout the perioperative period, with no significant differences between the groups at any stage during the study. There was a significant decline in postoperative pulmonary function tests in both groups, but there was no difference between groups at 72 hours postoperatively. No differences were found in the time to extubation, atelectasis scores, or postoperative complications.
  
  
  CONCLUSIONS
  Off-pump CABG does not confer major protection from postoperative pulmonary dysfunction compared with CABG surgery with CPB. Strategies for minimizing pulmonary impairment after CABG surgery should be directed to factors other than the use of CPB.
authors.affiliation: Department of Anesthesiology, Fundación Cardio Infantil, Instituto de Cardiología, Universidad del Rosario, Bogotá, Colombia. felixmontes@etb.net.co
authors.forename: Félix R
authors.initials: FR
authors.lastname: Montes
authors.forename: Javier D
authors.initials: JD
authors.lastname: Maldonado
authors.forename: Silvia
authors.initials: S
authors.lastname: Paez
authors.forename: Freddy
authors.initials: F
authors.lastname: Ariza
mesh_terms: D001784:Blood Gas Analysis / Q000379:methods; D002315:Cardiopulmonary Bypass / Q000009:adverse effects*; D001026:Coronary Artery Bypass / Q000009:adverse effects* / Q000379:methods; D047549:Coronary Artery Bypass, Off-Pump / Q000009:adverse effects* / Q000379:methods; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging / Q000503:physiopathology; D008171:Lung Diseases / Q000175:diagnosis / Q000209:etiology*; D008875:Middle Aged; D011183:Postoperative Complications / Q000175:diagnosis / Q000209:etiology*; D011446:Prospective Studies; D011859:Radiography; D012129:Respiratory Function Tests / Q000379:methods / Q000706:statistics & numerical data; D013997:Time Factors