title: Health economic modeling of the potential cost saving effects of Neurally Adjusted Ventilator Assist.
abstract: OBJECTIVE
  Asynchrony between patient and ventilator breaths is associated with increased duration of mechanical ventilation (MV). Neurally Adjusted Ventilatory Assist (NAVA) controls MV through an esophageal reading of diaphragm electrical activity via a nasogastric tube mounted with electrode rings. NAVA has been shown to decrease asynchrony in comparison to pressure support ventilation (PSV). The objective of this study was to conduct a health economic evaluation of NAVA compared with PSV.
  
  
  METHODS
  We developed a model based on an indirect link between improved synchrony with NAVA versus PSV and fewer days spent on MV in synchronous patients. Unit costs for MV were obtained from the Swedish intensive care unit register, and used in the model along with NAVA-specific costs. The importance of each parameter (proportion of asynchronous patients, costs, and average MV duration) for the overall results was evaluated through sensitivity analyses.
  
  
  RESULTS
  Base case results showed that 21% of patients ventilated with NAVA were asynchronous versus 52% of patients receiving PSV. This equals an absolute difference of 31% and an average of 1.7 days less on MV and a total cost saving of US$7886 (including NAVA catheter costs). A breakeven analysis suggested that NAVA was cost effective compared with PSV given an absolute difference in the proportion of asynchronous patients greater than 2.5% (49.5% versus 52% asynchronous patients with NAVA and PSV, respectively). The base case results were stable to changes in parameters, such as difference in asynchrony, duration of ventilation and daily intensive care unit costs.
  
  
  CONCLUSIONS
  This study showed economically favorable results for NAVA versus PSV. Our results show that only a minor decrease in the proportion of asynchronous patients with NAVA is needed for investments to pay off and generate savings. Future studies need to confirm this result by directly relating improved synchrony to the number of days on MV.
authors.affiliation: IMS Health HEOR, Sveavägen 155, Stockholm, Sweden Amgen (Europe) GmbH, Dammstrasse 23, Zug, Switzerland.
authors.forename: Jonas
authors.initials: J
authors.lastname: Hjelmgren
authors.affiliation: IMS Health HEOR, Sveavägen 155, Stockholm, Sweden.
authors.forename: Sara
authors.initials: S
authors.lastname: Bruce Wirta
authors.affiliation: IMS Health HEOR, Sveavägen 155, Stockholm, Sweden.
authors.forename: Pernilla
authors.initials: P
authors.lastname: Huetson
authors.affiliation: IMS Health HEOR, Sveavägen 155, Stockholm, Sweden SOBI, Tomtebodavägen 23A, Solna, Sweden.
authors.forename: Karl-Johan
authors.initials: KJ
authors.lastname: Myrén
authors.affiliation: Maquet Critical Care AB, Röntgenvägen 2, Solna, Sweden sylvia.gothberg@maquet.com.
authors.forename: Sylvia
authors.initials: S
authors.lastname: Göthberg
mesh_terms: D017046:Cost Savings; D003362:Cost-Benefit Analysis; D003964:Diaphragm / Q000502:physiology; D006801:Humans; D007362:Intensive Care Units / Q000191:economics; D059725:Interactive Ventilatory Support / Q000191:economics* / Q000379:methods; D018803:Models, Economic; D012121:Respiration, Artificial / Q000191:economics* / Q000379:methods; D013548:Sweden
keywords: Neurally Adjusted Ventilatory Assist; asynchrony; economic model; intensive care; mechanical ventilation; pressure support ventilation