Hyperbare Zuurstoftherapie: Rapid Assessment - KCE

46 Hyperbaric Oxygenation Therapy KCE Reports 74
Table 9. Base case model parameters 79
healing minor LEAs major LEAs unhealed
HBOT treatment 56% a 27% a 11% a 6% a
No HBOT treatment 24% a 16% a 33% a 28%a
Number of deaths annually 0.083 b 0.083 0.133 c - 0.083 0.083
LEA: lower extremity amputations
a: based on the average of seven controlled clinical studies: Baroni et al., 100 Doctor er al., 99 Faglia
et al., 98 Zamboni et al., 101 Faglia et al., 107 Kalani et al, 108 and Abidia et al. 80 b: 1/12=0.083, as a
result, the mortality rate (i.e., deaths divided by survivors) will increase with each passing year. 105
c: There is a 5% addition to the mortality rate in the first year for persons who have a major
LEA. 109
The time horizon was 12 years. This was equal to the life expectancy of 18 years for a
person in Alberta, 110 adjusted with a ratio for the expected lifetime of a person with
diabetes, which was 0.67. 105 No discount rate was mentioned. The perspective was that
of a ministry of health.
The total cost for 30 HBOT treatments was 3 652 Canadian dollars (CAD) (30 x
CAD110 per dive + CAD352 physician fees for first day, minor consult, and additional
time). The annual cost per patient is summarized in Table 10. The costs for minor and
major LEA include the operation costs. All costs were adjusted to 2004 values using the
Consumer Price Index. Two sensitivity analyses, changing the outcome probabilities
(16% major LEA instead of 6%) and the cost of HBOT, were conducted to assess the
stability of the model.
Table 10. Annual costs (in CAD, 2004 values) 79
healing minor LEAs major LEAs unhealed
First year 4 228 10 823 19 195 9 386
Subsequent year 3 890 10 484 11 712 9 428
The life expectancy was 5.96 and 5.84 life years or 3.64 and 3.01 QALYs in the HBOT
and control arm, respectively. This was associated with a 12-year cost for a patient
receiving HBOT of CAD40 695 compared to CAD49 786 for standard care alone.
Because outcomes were assumed better and costs were less in the HBOT arm,
adjunctive HBOT used with standard care dominated standard care alone. This
remained the case in the sensitivity analyses.
In conclusion, adjunctive HBOT used with standard care was a dominant strategy. It
would be necessary for health authorities to ensure that there was sufficient HBOT
capacity to cope with diabetic foot ulcers and that patients had reasonable access to
HBOT facilities.
4.3.1.4 Medical Services Advisory Committee 69
In this Australian report (2000) the cost-effectiveness of monoplace HBOT was
calculated in comparison with procedures not using HBOT. Multiplace chambers, which
are most of the times provided through the public hospital system, were not included in
the appraisal. The cost per patient treated in public multiplace units would likely be
higher than in a monoplace unit given the wider role of multiplace units including the
provision of 24 hour emergency care. No explicit information on the time window or
perspective was provided. Results were expressed as cost per amputation avoided,
which included only major or both major and minor amputations.
The risk for major amputations was based on five studies reporting absolute risk
reductions associated with HBOT. 98-101, 107 The pooled risk difference indicated a
reduction of 20% (95% CI: 11-30%). The risk for minor amputations was based on two
studies which reported a non-significant increase in the risk of minor amputations.
The pooled risk difference indicated an increase of 9% (95% CI: -8-25%) following
HBOT.
98, 99