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Principal Investigator(s)




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IOStudy — International Observational Study

Background: The requirement for mechanical ventilation is a defining feature of critical illness. Weaning is the process during which the work of breathing is transferred from the ventilator back to the patient. Approximately 40% of the total time spent on mechanical ventilation is dedicated to weaning. The extent and predictors of practice variation in how this complicated and expensive technology is discontinued from critically ill patients remains unknown. Meanwhile, practice pattern variability has been shown to adversely impact upon patient safety and important clinical outcomes.

Overarching Goal: To describe variation in weaning practices on national and international levels.

Primary Objectives:
  1. To describe weaning practice variation with regard to the (i) use of daily screening, (ii) preferred methods of support used before initial discontinuation attempts, (iii) use of written weaning and spontaneous breathing trial (SBT) protocols, (iv) preferred methods used to conduct SBTs and (v) sedation and mobilization practices among geographic regions.
  2. To describe the association between variation in weaning practices (direct extubation, tracheostomy, SBT conduct) and important clinical outcomes.
Secondary Objectives:
  1. To identify baseline and time-dependent factors associated with use of selected strategies.
  2. Among critically ill adults who undergo an initial SBT, we will: a) investigate associations between SBT outcome (success/failure) and clinical outcomes, b) explore differences between critically ill patients who undergo an SBT early versus later in their intensive care unit (ICU) stay, and c) investigate the impact of different SBT techniques and humidification strategies on clinical outcomes.
Tertiary Objective:
  1. To identify important predictors (patient, clinician, SBT, institutional and regional) of initial SBT outcome.
Study Design: We propose to conduct an international, prospective, observational study of mechanical ventilation discontinuation practices in approximately 150 ICUs.

Study Population: All newly admitted critically ill adults receiving invasive ventilation for at least 24 hours.

Study Centres: Approximately 25 ICUs in each of 6 geographic regions (Canada, India, the USA, UK, Europe, and Australia/New Zealand).

Study Outcomes: We will classify each new admission over the study week according to the initial strategy that precipitated or facilitated mechanical ventilation discontinuation into one of five categories: direct extubation, tracheostomy, SBT success, SBT failure or death. We will describe the association between the use of alternative discontinuation strategies and important clinical outcomes (e.g., mortality, ICU and hospital stay, ICU readmission and reintubation rates).