Abstract
Introduction: Hospital readmission and mortality following severe exacerbations of COPD requiring acute non-invasive ventilation (NIV) remain high. We hypothesised that HMV and HOT, following cessation of acute NIV, would be superior to HOT alone.
Method: An open labelled parallel randomised controlled trial comparing HMV and HOT with HOT alone was performed. The primary outcome was 1-year admission free survival. Patients with persistent hypercapnia (PaCO2 >7kPa) 2-4 weeks after resolution of respiratory acidosis were recruited. Minimisation was based on BMI, previous use of LTOT, exacerbation frequency and recruiting centre. Patients with BMI >35 kg/m2 or OSA syndrome were excluded.
Results: 116 patients were recruited (67.0±9.6 years, 53% female, BMI 21.6 (18.2-26.1)kg/m2, FEV1 0.6±0.2L and PaCO2 (7.9±0.9kPa). 59 patients were allocated to HOT (1.0 (0.5-2)Lpm) and 57 to HOT-HMV (O2 1.0 (0.5-1.5)Lpm) with an IPAP 24 (22-26)cmH2O, EPAP 4 (4-5)cmH2O and back up rate 14 (14-16)bpm. Median admission free survival was 4.3 months in the HOT-HMV group and 1.4 months in the HOT group; unadjusted HR 0.54 (0.34-0.84); p=0.007, adjusted HR 0.49 (0.31-0.77); p=0.002.
Conclusion: Although prognosis is poor in patients with persistent hypercapnia post exacerbation of COPD, the addition of HMV to HOT improved admission free survival.
- Copyright ©the authors 2016