Article Text
Abstract
Objectives & Background We aimed to determine the cost-effectiveness of pre-hospital CPAP compared with standard care for adults presenting to the emergency services with acute respiratory failure.
Methods An economic model was developed to explore the costs and health outcomes when pre-hospital CPAP provided by paramedics and standard care (in-hospital non-invasive ventilation (NIV)) were applied to a hypothetical cohort with acute respiratory failure. The model assigned each patient a probability of intubation or death depending upon their characteristics and whether they had pre-hospital CPAP or standard care. The patients that survived accrued lifetime quality-adjusted life year (QALYs) and health care costs according to their age and sex. Costs were accrued through costs of intervention and hospital treatment costs, which depended on patient outcomes.
Results Pre-hospital CPAP was more effective than standard care but was also more expensive, with an incremental cost-effectiveness ratio (ICER) of £20,514/QALY and a 49.5% probability of being cost-effective at the £20,000/QALY threshold. The probability of pre-hospital CPAP being cost-effective at the £20,000/QALY threshold depended on the incidence of eligible patients, and varied from 35.4% when a low estimate of incidence was used to 91.3% with a high estimate. If a typical ambulance service treated 175 appropriate patients per year it could save around 11 lives while incurring £241,250 additional costs, whereas if a typical ambulance service treated 2000 appropriate patients per year it could save 124 lives while incurring £876,480 additional costs. Variation in the incidence of eligible patients also had a marked impact on the expected value of sample information for a future randomised trial.
Conclusion The cost-effectiveness of pre-hospital CPAP is uncertain and current evidence is insufficient to support widespread implementation. The immediate research priority is to estimate the incidence of patients eligible for pre-hospital CPAP. This appears to be the key determinant of the cost-effectiveness of a future trial and of pre-hospital CPAP itself⇓.
Model structure
- emergency care systems