OBJECTIVES: Intensive care unit (ICU) patients often require sedation to attenuate anxiety and agitation and to improve mechanical ventilation synchrony. This study compares the costs and outcomes associated with inhaled isoflurane sedation via the AnaConDa and intravenous sedation with propofol/midazolam. The patient population comprises surgical ICU patients sedated for ≥96 hours. The perspective is from the UK NHS.

METHODS: A decision-analytic model was developed to estimate comparative costs and outcomes. Clinical data were taken from a German study of long-term ventilated, surgical ICU patients. This retrospective study, reported by Bellgardt et al. (2016), reports in-hospital mortality and 365-day mortality for patients receiving isoflurane (using AnaConDa) or propofol/midazolam. The mean duration of invasive ventilation, from Bellgardt et al., was taken as a proxy for the mean duration of sedation. A published survey of sedation practice in UK adult general critical care units provided estimates for the current use of propofol and midazolam. Expert opinion informed treatment switches from propofol to midazolam in long-term sedated patients.

RESULTS: The incremental cost of inhaled isoflurane sedation via the AnaConDa versus propofol/midazolam was estimated to be £3,861 per patient. It is estimated that per 100 sedated patients, 26 in-patient deaths and 21 deaths at 365 days could be avoided each year; a reduction of 41% and 30% respectively. The cost per additional patient leaving hospital alive is estimated to be £15,042; the cost per death avoided at 365 days is estimated to be £18,285. If patients surviving to 365 days survive a further six months at a threshold utility of 0.61, the use of AnaConDa would be considered cost-effective at a threshold of £20,000 per QALY.

CONCLUSIONS: This study provides an example of the potential clinical and economic benefits of sedation with AnaConDa versus propofol/midazolam in surgical ICU patients requiring long-term mechanical ventilation.