title: Comparisons of predictive performance of breathing pattern variability measured during T-piece, automatic tube compensation, and pressure support ventilation for weaning intensive care unit patients from mechanical ventilation.
abstract: OBJECTIVE
  To investigate the influence of different ventilatory supports on the predictive performance of breathing pattern variability for extubation outcomes in intensive care unit patients.
  
  
  METHODS
  A prospective measurement of retrospectively analyzed breathing pattern variability in a medical center.
  
  
  METHODS
  Sixty-eight consecutive and ready-for-weaning patients were divided into success (n=45) and failure (n=23) groups based on their extubation outcomes.
  
  
  METHODS
  Breath-to-breath analyses of peak inspiratory flow, total breath duration, tidal volume, and rapid shallow breathing index were performed for three 30-min periods while patients randomly received T-piece, 100% inspiratory automatic tube compensation with 5 cm H2O positive end-expiratory pressure, and 5 cm H2O pressure support ventilation with 5 cm H2O positive end-expiratory pressure trials. Coefficient of variations and data dispersion (standard descriptor values SD1 and SD2 of the Poincaré plot) were analyzed to serve as breathing pattern variability indices.
  
  
  RESULTS
  Under all three trials, breathing pattern variability in extubation failure patients was smaller than in extubation success patients. Compared to the T-piece trial, 100% inspiratory automatic tube compensation with 5 cm H2O positive end-expiratory pressure and 5 cm H2O pressure support ventilation with 5 cm H2O positive end-expiratory pressure decreased the ability of certain breathing pattern variability indices to discriminate extubation success from extubation failure. The areas under the receiver operating characteristic curve of these breathing pattern variability indices were: T-piece (0.73-0.87)>100% inspiratory automatic tube compensation with 5 cm H2O positive end-expiratory pressure (0.60-0.79)>5 cm H2O pressure support ventilation with 5 cm H2O positive end-expiratory pressure (0.53-0.76). Analysis of the classification and regression tree indicated that during the T-piece trial, a SD1 of peak inspiratory flow>3.36 L/min defined a group including all extubation success patients. Conversely, the combination of a SD1 of peak inspiratory flow ≤3.36 L/min and a coefficient of variations of rapid shallow breathing index ≤0.23 defined a group of all extubation failure patients. The decision strategies using SD1 of peak inspiratory flow and coefficient of variations of rapid shallow breathing index measured during 100% inspiratory automatic tube compensation with 5 cm H2O positive end-expiratory pressure and 5 cm H2O pressure support ventilation with 5 cm H2O positive end-expiratory pressure trials achieved a less clear separation of extubation failure from extubation success.
  
  
  CONCLUSIONS
  Since 100% inspiratory automatic tube compensation with 5 cm H2O positive end-expiratory pressure and 5 cm H2O pressure support ventilation with 5 cm H2O positive end-expiratory pressure reduce the predictive performance of breathing pattern variability, breathing pattern variability measurement during the T-piece trial is the best choice for predicting extubation outcome in intensive care unit patients patients.
authors.affiliation: School of Respiratory Therapy, Department of Physiology, Biostatistics and Research Consultion Center, and Division of Pulmonary Medicine, Taipei Medical University Hospital, and Institute of Physiology, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Mauo-Ying
authors.initials: MY
authors.lastname: Bien
authors.forename: You
authors.initials: Y
authors.lastname: Shui Lin
authors.forename: Chung-Hung
authors.initials: CH
authors.lastname: Shih
authors.forename: You-Lan
authors.initials: YL
authors.lastname: Yang
authors.forename: Hui-Wen
authors.initials: HW
authors.lastname: Lin
authors.forename: Kuan-Jen
authors.initials: KJ
authors.lastname: Bai
authors.forename: Jia-Horng
authors.initials: JH
authors.lastname: Wang
authors.forename: Yu
authors.initials: Y
authors.lastname: Ru Kou
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002986:Clinical Trials as Topic; D005260:Female; D006801:Humans; D007362:Intensive Care Units / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D011175:Positive-Pressure Respiration / Q000379:methods*; D012372:ROC Curve; D012119:Respiration; D012129:Respiratory Function Tests; D012189:Retrospective Studies; D015300:Ventilator Weaning / Q000379:methods*