title: Single-lung ventilation time does not increase lung injury after totally endoscopic coronary artery bypass surgery.
abstract: BACKGROUND
  Over the last decade, totally endoscopic procedures on the beating heart and on the arrested heart have made their way into cardiac surgery. Single-lung ventilation (SLV) is a prerequisite for performing totally endoscopic coronary artery bypass surgery (TECAB). The aim of the present study was to evaluate the influence of SLV on perioperative respiratory parameters and to determine additional predictors of respiratory problems in these patients.
  
  
  METHODS
  We investigated 16 female and 69 male patients (median age, 59 years; range, 38-90 years) who underwent either arrested heart TECAB (n = 76) or beating heart TECAB (n = 9). We analyzed the correlations of the SLV, cardiopulmonary bypass (CPB), aortic cross-clamping, and overall procedure times with perioperative respiratory parameters and length of intensive care unit (ICU) stay.
  
  
  RESULTS
  Preoperative values for forced vital capacity and the forced expiratory volume in 1 second were negatively correlated with postoperative pulmonary dysfunction. Longer total operative times were correlated with prolonged mechanical ventilation, tube continuous positive airway pressure ventilation (tube CPAP) time, and ICU and hospital stays. Increased CPB times were associated with longer tube CPAP times, higher grades of pulmonary dysfunction, and a prolonged hospital stay. A prolonged aortic-occlusion time increased the postoperative time to extubation and the hospital stay. Postoperative pulmonary dysfunction was associated with a history of smoking, a poor preoperative respiratory status, and a prolonged CPB time. SLV, however, did not correlate with postoperative time to extubation or with length of ICU stay. Only in patients who underwent conversion to sternotomy (n = 13) was SLV associated with prolonged mechanical ventilation.
  
  
  CONCLUSIONS
  Preoperative respiratory status showed no major influence on postoperative respiratory outcome in selected patients. Longer operative, CPB, and aortic crossclamping times led to reversible lung injury after TECAB. Prolonged SLV times, however, did not increase the postoperative time to extubation or the length of ICU stay in TECAB patients.
authors.affiliation: University Clinic of Cardiac Surgery, Vienna Medical University, Vienna, Austria. dominik.wiedemann@i-med.ac.at
authors.forename: Dominik
authors.initials: D
authors.lastname: Wiedemann
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Bonaros
authors.forename: Thomas
authors.initials: T
authors.lastname: Schachner
authors.forename: Clara
authors.initials: C
authors.lastname: Schwaiger
authors.forename: Matthias
authors.initials: M
authors.lastname: Biebl
authors.forename: Guy
authors.initials: G
authors.lastname: Friedrich
authors.forename: Johannes
authors.initials: J
authors.lastname: Bonatti
authors.forename: Christian
authors.initials: C
authors.lastname: Kolbitsch
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001026:Coronary Artery Bypass / Q000379:methods*; D004724:Endoscopy / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012121:Respiration, Artificial / Q000009:adverse effects*; D016896:Treatment Outcome