Helicopter emergency medical services (HEMS) are popular in first world health systems
despite inconsistent evidence in the scientific literature to support their use. The
aim of the current study was to perform a systematic review of economic evaluations
of HEMS, in order to determine the economic cost of HEMS and the associated patient-centered
benefits.
A systematic review was performed of studies that provided a cost estimate of HEMS.
The inclusion criteria consisted of English language articles that estimated both
the costs and outcomes of a HEMS and fulfilled pre-specified criteria in relation
to a cost analysis, cost-minimisation, cost-effectiveness or cost-benefit evaluation.
Identified studies were synthesised according to the patient diagnosis (trauma, non-trauma
or non-specific) and the type of HEMS transport under review (primary scene retrieval
or secondary inter-facility transport). All costs were converted to US dollars and
indexed for inflation.
Fifteen studies met the inclusion criteria. Among all studies the annual cost of HEMS
ranged from $115,777 to $5,571,578. Five studies showed HEMS to be a more expensive
transport alternative without an associated benefit while eight studies provided cost-effectiveness
ratios of $3292 and $2227 per life year saved for trauma, $3258 per life saved and
$7138 and $12,022 per quality adjusted life year for non-trauma and $30,365 and $91,478
per beneficial mission for non-specific patient populations. One study also evaluated
the cost of HEMS to societal benefit, producing a ratio of 1:6.
The cost and effectiveness of HEMS varied considerably between studies. Despite generally
being more expensive than ground transport, a number of studies found HEMS to be cost-effective.
However, given the variation in the intervention design, context and study methods
between studies it was not possible to assess the cost-effectiveness of HEMS in general.
Given the variation inherent in the health systems in which HEMS operate, synthesis
and extrapolation of study findings across differing health environments is difficult.
To address economic and clinical evidence in relation to HEMS, future research that
is tailored to account for local system factors is required.