title: A randomized, controlled trial of the role of weaning predictors in clinical decision making.
abstract: OBJECTIVE
  Weaning predictors are often incorporated in protocols to predict weaning outcome for patients on mechanical ventilation. The predictors are used as a decision point in protocols to determine whether a patient may advance to a spontaneous breathing trial. The impact of including predictors in a weaning protocol has not been previously studied. We designed a study to determine the effect of including a weaning predictor (frequency-tidal volume ratio, or f/Vt) in a weaning protocol.
  
  
  METHODS
  Randomized, blinded controlled trial.
  
  
  METHODS
  Academic teaching hospitals.
  
  
  METHODS
  Three hundred and four patients admitted to intensive care units at three academic teaching hospitals.
  
  
  METHODS
  Patients were screened daily for measures of oxygenation, cough and secretions, adequate mental status, and hemodynamic stability. Patients were randomized to two groups; in one group the f/Vt was measured but not used in the decision to wean (n = 151), but in the other group, f/Vt was measured and used, using a threshold of 105 breaths/min/L (n = 153). Patients passing the screen received a 2-hr spontaneous breathing trial. Patients passing the spontaneous breathing trial were eligible for an extubation attempt.
  
  
  RESULTS
  Groups were similar with regard to gender, age, and Acute Physiology and Chronic Health Evaluation II score. The median duration for weaning time was significantly shorter in the group where the weaning predictor was not used (2.0 vs. 3.0 days, p = .04). There was no difference with regard to the extubation failure, in-hospital mortality rate, tracheostomy, or unplanned extubation.
  
  
  CONCLUSIONS
  Including a weaning predictor (f/Vt) in a protocol prolonged weaning time. In addition, the predictor did not confer survival benefit or reduce the incidence of extubation failure or tracheostomy. The results of this study indicate that f/Vt should not be used routinely in weaning decision making.
authors.affiliation: UCLA School of Medicine, Pulmonary and Critical Care Medicine, St. Mary Medical Center Long Beach, California and Long Beach Memorial Medical Center, Long Beach, CA, USA.
authors.forename: Maged A
authors.initials: MA
authors.lastname: Tanios
authors.forename: Michael L
authors.initials: ML
authors.lastname: Nevins
authors.forename: Katherine P
authors.initials: KP
authors.lastname: Hendra
authors.forename: Pierre
authors.initials: P
authors.lastname: Cardinal
authors.forename: Jill E
authors.initials: JE
authors.lastname: Allan
authors.forename: Elena N
authors.initials: EN
authors.lastname: Naumova
authors.forename: Scott K
authors.initials: SK
authors.lastname: Epstein
mesh_terms: D000328:Adult; D000368:Aged; D002985:Clinical Protocols; D003661:Decision Support Techniques; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012306:Risk; D016037:Single-Blind Method; D013997:Time Factors; D015300:Ventilator Weaning / Q000379:methods*