Mechanical Ventilation Discontinuation Practices (IOS)

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.

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:

3. To identify baseline and time-dependent factors associated with use of selected strategies.
4. Among critically ill adults who undergo an initial SBT, the investigators 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 outcomes.
5. To identify important predictors (patient, clinician, SBT, institutional and regional) of SBT outcome.

Study Design and Population: The investigators propose to conduct an international prospective observational study of mechanical ventilation discontinuation practices in 150 ICUs involving all newly admitted critically ill adults requiring invasive ventilation for at least 24 hours.

Study Centres: Interested centres have been identified through completion of an information card enclosed in a previously administered International Weaning Survey. The investigators will use a multimodal approach to identify participating centers in each of the 6 geographic regions (Canada, the United States, the United Kingdom, Europe, India and Australia/New Zealand).

Study Outcomes: The investigators 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. The investigator 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).

Relevance: Through collaborations with industry partners and international colleagues we will implement this large scale observational study to quantify the existence and extent of practice variation in weaning. Information obtained from this study will inform the design of future studies aimed at reducing weaning practice variation and improving outcomes in critically ill patients receiving invasive mechanical ventilation