Extracorporeal carbon dioxide removal compared to ventilation alone in patients with acute hypoxaemic respiratory failure: cost-utility analysis of the REST RCT

BackgroundAcute hypoxaemic respiratory failure requiring mechanical ventilation is a major cause of morbidity and mortality and has significant resource implications in terms of intensive care unit and hospital stay. ObjectiveTo assess the cost-effectiveness of extracorporeal carbon dioxide removal compared to ventilation alone in patients with acute hypoxaemic respiratory failure. DesignA cost-utility analysis embedded within a pragmatic, multicentre, allocation-concealed, open-label, randomised controlled trial. ParticipantsFour hundred and twelve (of a planned sample size of 1120) adult patients receiving mechanical ventilation for acute hypoxaemic respiratory failure, were recruited between May 2016 and December 2019 from 51 intensive care units in the UK. InterventionsParticipants were randomised (1 : 1) to receive extracorporeal carbon dioxide removal for at least 48 hours (n = 202) or standard care with ventilation alone (n = 210). OutcomesHealth-related quality of life via the EuroQol-5 Dimensions, five-level version, health resource use and associated costs were measured over the study period. The cost per quality-adjusted life-year was estimated at 12 months post randomisation. ResultsMean EuroQol-5 Dimensions, five-level version utility scores were low and similar for each group. Quality-adjusted life-years were calculated for those patients with complete EuroQol-5 Dimensions, five-level version data (extracorporeal carbon dioxide removal n = 140, ventilation alone n = 143) and there was no discernible difference in quality-adjusted life-years at 12 months (mean difference -0.01; 95% confidence interval -0.06 to 0.05; 140). Total 12-month health resource use cost (including intervention costs) was calculated for those patients with complete cost data (extracorporeal carbon dioxide removal n = 125, ventilation alone n = 126) and costs were statistically significantly higher in the extracorporeal carbon dioxide removal group (mean difference £7668.76, 95% confidence interval 159.75, 15,177.77). Multiple imputation was used for missing total cost and quality-adjusted life-year data in the cost-utility analysis. Ventilation alone dominated extracorporeal carbon dioxide removal and there was 0% probability of extracorporeal carbon dioxide removal being cost-effective compared to ventilation alone for all willingness to pay thresholds per quality-adjusted life-year considered (£0-50,000). ConclusionsExtracorporeal carbon dioxide removal was associated