title: Breathing pattern variability: a weaning predictor in postoperative patients recovering from systemic inflammatory response syndrome.
abstract: OBJECTIVE
  To investigate whether breathing pattern variability can serve as a potential weaning predictor for postoperative patients recovering from systemic inflammatory response syndrome (SIRS).
  
  
  METHODS
  A prospective measurement of retrospectively analyzed breathing pattern variability in a surgical intensive care unit.
  
  
  METHODS
  Seventy-eight mechanically ventilated SIRS patients who had undergone abdominal surgery were included when they were ready for weaning. They were divided into success (n=57) and failure (n=21) groups based upon their weaning outcome.
  
  
  RESULTS
  Before weaning, tidal volume, total breath duration, inspiratory time, expiratory time, and peak inspiratory flow were continuously monitored for 30 min, while patients received 5 cmH2O pressure support weaning trial. After the patients successfully completed the trial, they were extubated. Successful weaning was defined as patients free from the ventilator for over 48 h, whereas a weaning failure was considered as reinstitution of mechanical ventilation within 48 h of extubation. The coefficient of variation and two values of standard deviation (SD1 and SD2; indicators of the dispersion of data points in the plot) obtained from the Poincaré plot of five respiratory parameters in the failure group were significantly lower than those in the success group. The area under the receiver operating characteristic curve of these variability indices was within the range of 0.73-0.80, indicating the accuracy of prediction.
  
  
  CONCLUSIONS
  Small breathing pattern variability is associated with a high incidence of weaning failure in postoperative patients recovering from SIRS, and this variability may potentially serve as a weaning predictor.
authors.affiliation: Institute of Physiology, School of Medicine, National Yang-Ming University, 11221, Taipei, Taiwan, Republic of China.|Department of Respiratory Therapy, Taipei Veterans General Hospital, 11217, Taipei, Taiwan, Republic of China.
authors.forename: Mauo-Ying
authors.initials: MY
authors.lastname: Bien
authors.affiliation: Department of Anesthesiology, Department of Surgical Critical Care Unit, Taipei Veterans General Hospital, 11217, Taipei, Taiwan, Republic of China.
authors.forename: Shu-Shya
authors.initials: SS
authors.lastname: Hseu
authors.affiliation: Department of Anesthesiology, Department of Surgical Critical Care Unit, Taipei Veterans General Hospital, 11217, Taipei, Taiwan, Republic of China.
authors.forename: Huey-Wen
authors.initials: HW
authors.lastname: Yien
authors.affiliation: Laboratory of Epidemiology and Biostatistics, Taipei Veterans General Hospital, 11217, Taipei, Taiwan, Republic of China.
authors.forename: Benjamin Ing-Tiau
authors.initials: BI
authors.lastname: Kuo
authors.affiliation: Department of Anesthesiology, Department of Surgical Critical Care Unit, Taipei Veterans General Hospital, 11217, Taipei, Taiwan, Republic of China.
authors.forename: Yu-Ting
authors.initials: YT
authors.lastname: Lin
authors.affiliation: Department of Respiratory Therapy, Taipei Veterans General Hospital, 11217, Taipei, Taiwan, Republic of China.
authors.forename: Jia-Horng
authors.initials: JH
authors.lastname: Wang
authors.affiliation: Institute of Physiology, School of Medicine, National Yang-Ming University, 11221, Taipei, Taiwan, Republic of China. yrkou@ym.edu.tw.
authors.forename: Yu Ru
authors.initials: YR
authors.lastname: Kou
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011182:Postoperative Care; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012129:Respiratory Function Tests; D015656:Respiratory Mechanics; D012189:Retrospective Studies; D018746:Systemic Inflammatory Response Syndrome / Q000503:physiopathology* / Q000628:therapy; D015300:Ventilator Weaning