title: An automated and standardized neural index to quantify patient-ventilator interaction.
abstract: BACKGROUND
  The aim of this study was to validate an automated, objective and standardized algorithm for quantifying and displaying patient-ventilator interaction.
  
  
  METHODS
  Using a new method to detect patient-ventilator synchrony, the present study re-analyzed previously acquired and published data from 24 mechanically ventilated adult patients (Colombo et al., Crit Care Med. 2011 Nov;39(11):2452-7). Patient-ventilator interactions were evaluated by comparing ventilator pressure and diaphragm electrical activity (EAdi) waveforms, recorded during pressure support ventilation. The EAdi and ventilator pressure waveforms were analyzed for their timings (manually and automatically determined), and the error between the two waveforms was quantified. A new index of patient-ventilator interaction (NeuroSync index), which is standardized and automated, was validated and compared to manual analysis and previously published indices of asynchrony.
  
  
  RESULTS
  The comparison of manual and automated detection methods produced high test-retest and inter-rater reliability (Intraclass correlation coefficient = 0.95). The NeuroSync index increased the sensitivity of detecting dyssynchronies, compared to previously published indices, which were found to only detect asynchronies.
  
  
  CONCLUSIONS
  The present study introduces an automated method and the NeuroSync index to determine patient-ventilator interaction with a more sensitive analysis method than those previously described. A dashboard-style of graphical display allows a rapid overview of patient-ventilator interaction and breathing pattern at the bedside.
authors.forename: Christer
authors.initials: C
authors.lastname: Sinderby
authors.forename: Songqiao
authors.initials: S
authors.lastname: Liu
authors.forename: Davide
authors.initials: D
authors.lastname: Colombo
authors.forename: Gianmaria
authors.initials: G
authors.lastname: Camarotta
authors.forename: Arthur S
authors.initials: AS
authors.lastname: Slutsky
authors.forename: Paolo
authors.initials: P
authors.lastname: Navalesi
authors.forename: Jennifer
authors.initials: J
authors.lastname: Beck
mesh_terms: D000328:Adult; D006801:Humans; D007362:Intensive Care Units; D059725:Interactive Ventilatory Support / Q000379:methods*; D015203:Reproducibility of Results; D012129:Respiratory Function Tests; D012815:Signal Processing, Computer-Assisted