title: Intraoperative conversion to on-pump coronary artery bypass grafting is independently associated with higher mortality in patients undergoing off-pump coronary artery bypass grafting: A propensity-matched analysis.
abstract: BACKGROUND
  One of the main limitations of off-pump coronary artery bypass grafting (OPCAB) is the occasional need for intraoperative conversion (IOC) to on-pump coronary artery bypass grafting. IOC is associated with a significantly increased risk of mortality and postoperative morbidity. The impact of IOC on outcome cannot be assessed by a randomized control design.
  
  
  OBJECTIVE
  The objective of this study was to analyze the incidence, risk factors, and impact of IOC on the outcome in patients undergoing OPCAB.
  
  
  METHODS
  Three tertiary care level hospitals; retrospective observational study.
  
  
  METHODS
  This retrospective observational study included 1971 consecutive patients undergoing  OPCAB from January 2012 to October 2015 at three tertiary care level hospitals by four surgeons. The incidence, patient characteristics, cause of IOC, and its impact on outcome were studied.
  
  
  METHODS
  The cohort was divided into two groups according to IOC. Univariate logistic regression was performed to describe the predictors of IOC. Variables that were found to be significant in univariate analysis were introduced into multivariate model, and adjusted odds ratio (OR) was calculated. To further assess the independent effect of IOC on mortality, propensity score matching with a 5:1 ratio of non-IOC to IOC was performed.
  
  
  RESULTS
  The overall all-cause in-hospital mortality was 2.6%. IOC was needed in 128 (6.49%) patients. The mortality in the IOC group was significantly higher than non-IOC group (21 of 128 [16.4%] vs. 31 of 1843 [1.7%], P = 0.0001). The most common cause for IOC was hemodynamic disturbances during grafting to the obtuse marginal artery (51/128; 40%). On multivariate logistic regression analysis, left main disease, pulmonary hypertension, and mitral regurgitation independently predicted IOC. We obtained a propensity-matched sample of 692 patients (No IOC 570; IOC 122), and IOC had OR of 16.26 (confidence interval 6.3-41; P < 0.0001) for mortality in matched population.
  
  
  CONCLUSIONS
  Emergency IOC increases odds for mortality by 16-fold. Hence, identification of patients at higher risk of IOC may improve the outcome.
authors.affiliation: Ozone Anesthesia Group, Aurangabad, Maharashtra, India.
authors.forename: Deepak Prakash
authors.initials: DP
authors.lastname: Borde
authors.affiliation: Ozone Anesthesia Group, Aurangabad, Maharashtra, India.
authors.forename: Balaji
authors.initials: B
authors.lastname: Asegaonkar
authors.affiliation: Ozone Anesthesia Group, Aurangabad, Maharashtra, India.
authors.forename: Pramod
authors.initials: P
authors.lastname: Apsingekar
authors.affiliation: Ozone Anesthesia Group, Aurangabad, Maharashtra, India.
authors.forename: Sujeet
authors.initials: S
authors.lastname: Khade
authors.affiliation: Ozone Anesthesia Group, Aurangabad, Maharashtra, India.
authors.forename: Savni
authors.initials: S
authors.lastname: Futane
authors.affiliation: Ozone Anesthesia Group, Aurangabad, Maharashtra, India.
authors.forename: Bapu
authors.initials: B
authors.lastname: Khodve
authors.affiliation: Ozone Anesthesia Group, Aurangabad, Maharashtra, India.
authors.forename: Ajita
authors.initials: A
authors.lastname: Annachhatre
authors.affiliation: Seth Nandlal Dhoot Hospital, Aurangabad, Maharashtra, India.
authors.forename: Manish
authors.initials: M
authors.lastname: Puranik
authors.affiliation: Seth Nandlal Dhoot Hospital, Aurangabad, Maharashtra, India.
authors.forename: Sayaji
authors.initials: S
authors.lastname: Sargar
authors.affiliation: MGM College and Hospital, Mumbai, Maharashtra, India.
authors.forename: Yogesh
authors.initials: Y
authors.lastname: Belapurkar
authors.affiliation: United CIIGMA Hospital, Aurangabad, Maharashtra, India.
authors.forename: Anand
authors.initials: A
authors.lastname: Deodhar
authors.affiliation: Fortis Hospital, Bengaluru, Karnataka, India.
authors.forename: Antony
authors.initials: A
authors.lastname: George
authors.affiliation: Nayati Hospital, Mathura, Uttar Pradesh, India.
authors.forename: Shreedhar
authors.initials: S
authors.lastname: Joshi
mesh_terms: D001026:Coronary Artery Bypass / Q000009:adverse effects / Q000379:methods / Q000401:mortality*; D047549:Coronary Artery Bypass, Off-Pump / Q000009:adverse effects / Q000379:methods / Q000401:mortality; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D015994:Incidence; D007430:Intraoperative Care / Q000009:adverse effects / Q000379:methods* / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011183:Postoperative Complications / Q000209:etiology*; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors