Hyperbare Zuurstoftherapie: Rapid Assessment - KCE

50 Hyperbaric Oxygenation Therapy KCE Reports 74
Costs for the hypothetical conservative therapy group, including costs of medications,
sequestrectomies, dental extractions, out-patient visits, in-patient days and
reconstructive surgery, were also calculated based on expected outcomes obtained
from the literature.
The cost for one dive in the chamber was CAD350.59, including the capital and
operational cost, the fees charged to the Ontario Health Insurance and the patient cost
per dive. Cost per day, average number of in-patient days and cost of reconstructive
surgery were changed in sensitivity analyses.
The total cost to treat the 21 hypothetical patients was found to be CAD1 327 444, or
an average of CAD63 211 per patient. In contrast, this was CAD211 362 for the 21
patients treated with HBOT or an average cost of CAD10 064 per patient. The number
of days in the hospital was an important cost driver. The osteoradionecrosis of the 21
patients in the treatment group healed, whereas, based on expected outcomes from the
literature, three cases would not be resolved under conservative therapy in the
hypothetical patient group.
According to the authors of this study, HBOT was both less expensive and more
effective than conservative therapy and, thus, demonstrated dominance.
4.3.3.2 Medical Services Advisory Committee 69
4.3.3.3 Comments
A third indication included in the Australian HTA report (2000) was osteoradionecrosis.
The study of Marx et al. 114 randomised two groups of patients who had an indication for
removal of one or more teeth in a segment of the mandible. The comparison group
received aqueous penicillin G intravenously prior to surgery and
phenoxymethylpenicillin after surgery. The intervention group was exposed to HBOT.
The main outcome of interest was the clinical diagnosis of osteoradionecrosis during
follow-up. Two out of 37 patients (5.4%) in the intervention group were diagnosed as
having osteoradionecrosis during follow up, compared to 11 out of 37 patients (29.7%)
in the comparison group, a difference of 24.3% (95% CI: 15.9%, 47.0%, p=0.0060). 69
The treatment cost in the comparison group was on average AUD13.6 compared to
AUD6 941 in the intervention group (30 HBOT sessions). This resulted in an
incremental cost of AUD28 480 per case of osteoradionecrosis avoided. Sensitivity
analysis using the upper and lower bound of the 95% CI suggested this cost to be
AUD16 663 and AUD66 187, respectively. Results were again sensitive to the number
of sessions and sharing of operating costs between units.
The main weakness of the study of Dempsey et al. 82 is that it compares an HBOT group
with a hypothetical group. The assumptions on the outcomes for the latter group
undergoing conservative therapy were taken from literature. Mitton et al. remark that
the non-HBOT outcome assumptions were based on weak evidence, and no reference
was provided for the non-HBOT length of stay, leading to uncertainty in reported cost
savings. 115 This indirect comparison resulted in very uncertain health gains and cost
differences and can not be regarded as reliable. Results should therefore be interpreted
with caution. A more precise measure of the true effectiveness of HBOT in this
indication is needed to calculate reliable cost-effectiveness ratios.
The Australian report was based on one study on the effectiveness of HBOT in
osteoradionecrosis.
This resulted in an incremental cost of AUD28 480 per case of osteoradionecrosis
avoided. As mentioned by the authors, this did not take into account the cost offsets
associated with prevention of osteoradionecrosis. Nonetheless, this cost per
osteoradionecrosis avoided is very difficult to interpret by decision makers.
In conclusion, and similar as for other indications, due to the absence of good
effectiveness and cost data, the cost-effectiveness of HBOT in this indication is
unknown.