S3 Standard versus accelerated weaning from non-invasive ventilation (NIV) in chronic obstructive pulmonary disease directed by the NIV outcomes score: a randomised controlled trial

Introduction
Acute NIV for exacerbation of chronic obstructive pulmonary disease (ECOPD) is one of the most effective interventions in emergency medicine, but it is intrusive and complications are common. NIV weaning guidance is limited and inconsistently followed. Our 10-centre NIV Outcomes study1 showed marked variation in duration of NIV, relapse (respiratory acidaemia requiring NIV more than 48 hours after successful weaning), inpatient and 90-day mortality.

Methods
We conducted a 7-centre, open-label, parallel, randomised controlled trial with embedded economic evaluation to compare time to successful weaning from NIV in ECOPD. Patients meeting a combination of clinical risk stratification (low or medium risk NIVO score) and objective weaning criteria were randomised to standard stepwise (SW) or accelerated (AW) weaning protocols (ISRCTN:64639614). SW reflected current BTS guidance. AW involved a 4-hour trial off NIV and arterial blood gas to exclude recurrent respiratory acidaemia. Not replacing NIV within 48 hours was considered successful weaning.

Results
Between October 2022 and April 2025, participants were randomised to SW (n=83) or AW (n=81): medium risk NIVO score= 61 (37.2%); female= 99 (60.4%); mean (SD) age= 68.6 (8.7); FEV1% predicted= 39.3 (15.2); duration of NIV prior to meeting weaning criteria= 37.8 (13.7) hours. Both groups were well matched. Median (IQR) hours to successful weaning was: SW= 46 hours (41–70), AW= 6 (5–7), p<0.0001. Competing risks precluding weaning, death during weaning (n=0) and failure to wean requiring transition to home NIV (n=2), were similar between groups. There was no difference in relapse (SW n=5, AW n=3), median (IQR) length of hospital stay after meeting weaning criteria (SW n=5 (3–7), AW n= 5 (2–8) days), one or more readmissions within 30 days of discharge (SW n=20, AW n=14), in-hospital mortality (SW n=2, AW n=3), or 90-day mortality (SW n=10, AW n=8).

Conclusions
In patients requiring NIV for ECOPD with a low or medium risk NIVO score and meeting objective weaning criteria, NIV was successfully removed 40 hours earlier using an accelerated weaning protocol with no increase in mortality or readmission. This releases NHS resources and may reduce complications for patients. Further trial analysis will be available for the winter BTS.