Impact case study database

Reducing the time that patients in intensive care units (ICUs) spend on mechanical ventilation by optimising their weaning from ventilator support is an important patient outcome and a top priority for critical care clinicians. Over recent years, weaning protocols were developed to guide clinicians in this process through encouraging more collaborative working and reducing variation in practice. In the early 2010s, 18% of UK paediatric ICUs had a weaning protocol, compared to 54% and 31% in UK and European adult ICUs, respectively. The relatively low proportion of uptake in paediatric ICUs can be attributed to clinicians’ understanding of, and belief in, the strength of evidence for their effectiveness, as well as the approaches used to introduce these protocols into the practice of ICU clinicians. The work of Blackwood, McAuley and Clarke at Queen’s University Belfast (QUB) has tackled these barriers and led to large-scale change in weaning practice in paediatric ICUs across the UK.

Blackwood synthesized research findings on weaning protocols worldwide, showing a clinically significant reduction of 6 hours (from 134 to 126 hours) (based on 260 children in 1 trial) in duration of mechanical ventilation when protocols were used in paediatric ICUs [R1] and of 25 hours (96 to 71 hours) in adult ICUs (2205 patients, 14 trials) [R2]. This work also highlighted considerable differences in how trial outcomes were measured, impeding the interpretation of this body of research. However, despite the beneficial effects of weaning protocols, there were discordant results among the adult trials, and just the one eligible trial in children. Blackwood explored reasons for the discordant results in a synthesis of 11 qualitative studies of staff views in adult and paediatric ICUs [R3] and identified facilitators and barriers to clinicians using weaning protocols. These included the extent of clinician experience; inter-professional hierarchies and collaboration; ICU workload; and user-friendliness of the protocol. These reasons are often ignored in designing and implementing strategies to improve weaning outcomes and the qualitative evidence synthesis provided evidence-based foundations for change.

The largest gaps in clinical practice related to the need for (1) evidence on the effects of weaning protocols in children with a strategy for ensuring successful implementation, and (2) agreement by patients, clinicians and researchers on the outcomes that are most important to measure in evaluations of weaning protocols. Blackwood, McAuley, and Clarke’s research helped to fill these gaps.

First, a quality improvement weaning protocol for children and an implementation strategy to maximise impact in the NHS was developed. The quality improvement intervention (Sedation AND Weaning In CHildren: SANDWICH) was developed following feasibility work with clinicians in 24 NHS paediatric ICUs [R4]. Blackwood’s assessment of practice in paediatric ICUs showed considerable variation in ventilator weaning practice and limited guidance on management of sedation to optimise readiness for weaning. Very few bedside nurses and junior medical staff were engaged in assessing patients for weaning and managing their weaning. Consequently, weaning was not done overnight and at weekends, and it only happened when consultants were available. This meant that many children were remaining on mechanical ventilation, exposed to its risks, for longer than they needed to be. Through engagement with parents and young people, Blackwood was able to show that the proposed intervention (which incorporated greater involvement of junior medical and bedside nurses in the weaning process) was acceptable, and that reducing time on the ventilator was an important outcome for them [R5]. The paediatric ICU community and the Paediatric Intensive Care Society deemed the SANDWICH intervention as a #1 priority. In 2018, its implementation across paediatric ICUs in the UK was commissioned by the NHS.

Second, Blackwood, McAuley, and Clarke gained international agreement on a core outcome set for ventilation trials and developed one of the first core outcome sets (COS) in critical care [R6]. This development process had international engagement from 27 countries in Europe, North and South America, Australia, Asia and Africa and involved ICU survivors and their carers; nurses, allied health professionals and critical care physicians; clinical trials groups and trial investigators; and industry. Collectively, they agreed the most important outcomes that should be measured in all assessment of mechanical ventilation and this consensus is allowing research designers, practitioners and policy makers to ensure that all future ventilation trials will measure these patient and clinically relevant outcomes in a standardised fashion.