title: Myocardial injury after surgery is a risk factor for weaning failure from mechanical ventilation in critical patients undergoing major abdominal surgery.
abstract: BACKGROUND
  Myocardial injury after noncardiac surgery (MINS) is a newly proposed concept that is common among adults undergoing noncardiac surgery and associated with substantial mortality. We analyzed whether MINS was a risk factor for weaning failure in critical patients who underwent major abdominal surgery.
  
  
  METHODS
  This retrospective study was conducted in the Department of Critical Care Medicine of Peking University People's Hospital. The subjects were all critically ill patients who underwent major abdominal surgery between January 2011 and December 2013. Clinical and laboratory parameters during the perioperative period were investigated. Backward stepwise regression analysis was performed to evaluate MINS relative to the rate of weaning failure. Age, hypertension, chronic renal disease, left ventricular ejection fraction before surgery, Acute Physiologic and Chronic Health Evaluation II score, pleural effusion, pneumonia, acute kidney injury, duration of mechanical ventilation before weaning and the level of albumin after surgery were treated as independent variables.
  
  
  RESULTS
  This study included 381 patients, of whom 274 were successfully weaned. MINS was observed in 42.0% of the patients. The MINS incidence was significantly higher in patients who failed to be weaned compared to patients who were successfully weaned (56.1% versus 36.5%; P<0.001). Independent predictive factors of weaning failure were MINS, age, lower left ventricular ejection fraction before surgery and lower serum albumin level after surgery. The MINS odds ratio was 4.098 (95% confidence interval, 1.07 to 15.6; P = 0.04). The patients who were successfully weaned had shorter hospital stay lengths and a higher survival rate than those who failed to be weaned.
  
  
  CONCLUSIONS
  MINS is a risk factor for weaning failure from mechanical ventilation in critical patients who have undergone major abdominal surgery, independent of age, lower left ventricular ejection fraction before surgery and lower serum albumin levels after surgery.
authors.affiliation: Department of Critical Care Medicine, Peking University People's Hospital, Beijing, China.
authors.forename: Shu
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Critical Care Medicine, Peking University People's Hospital, Beijing, China.
authors.forename: You-zhong
authors.initials: YZ
authors.lastname: An
authors.affiliation: Department of Cardiology, Peking University People's Hospital, Beijing, China.
authors.forename: Jing-yi
authors.initials: JY
authors.lastname: Ren
authors.affiliation: Department of Critical Care Medicine, Peking University People's Hospital, Beijing, China.
authors.forename: Feng-xue
authors.initials: FX
authors.lastname: Zhu
authors.affiliation: Department of Cardiology, Peking University People's Hospital, Beijing, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Chen
mesh_terms: D018806:APACHE; D000005:Abdomen / Q000601:surgery*; D058186:Acute Kidney Injury / Q000150:complications; D000368:Aged; D000369:Aged, 80 and over; D016638:Critical Illness; D005260:Female; D006335:Heart Injuries / Q000453:epidemiology / Q000209:etiology* / Q000401:mortality; D006801:Humans; D015994:Incidence; D007362:Intensive Care Units; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D059035:Perioperative Period; D011014:Pneumonia / Q000150:complications; D012189:Retrospective Studies; D012307:Risk Factors; D012709:Serum Albumin / Q000032:analysis; D015996:Survival Rate; D015300:Ventilator Weaning / Q000009:adverse effects*; D016277:Ventricular Function, Left / Q000502:physiology
chemical_list: D012709:Serum Albumin