Aanesthetic Agents for Day Surgery - NIHR Health Technology ...

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No. of patients
be lower in the sevoflurane/sevoflurane group
than for the other randomisation arms, although
this did not reach statistical significance. This
indicated a tendency to a lower magnitude of
preference for PONV avoidance in the group
with a significantly higher risk of PONV (versus
propofol/propofol, p = 0.098; versus propofol/
volatile arms, p = 0.093). The CVs given by patients
who received the propofol/propofol regimen were
no different from those given by the patients who
had received the combination of intravenous and
inhalational anaesthesia (p = 0.589).
The mean CVs for those patients who had and
who did not have PONV were £199.8 (n = 135,
SD = £142.0) and £192.6 (n = 574, SD = £156.8),
respectively (p = 0.565). Therefore, the CV of
patients was not affected by their experience of
the clinical outcome. This conclusion was not
altered when CVs were corrected by a factor of 2.5.
Figure 6 shows the distribution of CVs for maintenance
anaesthesia. It is clear that there is been
a scale effect for scenario D.
Reported income bands
Table 35 summarises the reported monthly income
bands of the adult study participants. There was
no difference in distribution between the
randomisation arms.
Income was not correlated with CVs (induction
CVs, Spearman’s ρ = –0.126, p = 0.0009; mainte-
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Health Technology Assessment 2002; Vol. 6: No. 30
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CVs (£)
FIGURE 6 Distribution of CVs for avoidance of PONV after maintenance anaesthesia (scenario D) in the adult study
TABLE 35 Reported monthly household income bands of
participants in the adult study
Monthly household income No. of patients
> £2000 148 (13.9%)
£1001 to £2000 304 (28.6%)
£501 to £1000 235 (22.1%)
£250 to £500 150 (14.1%)
< £250 23 (2.2%)
Income not given 44 (4.1%)
Lost to follow-up 159 (15.0%)
nance CVs, Spearman’s ρ = –0.074, p = 0.057)
(Figures 7 and 8).
Incremental cost-effectiveness
ratios
Sevoflurane/sevoflurane was less effective and
more costly than either of the mixed anaesthesia
regimens (i.e. was dominated by them). It was
less effective, but less costly than the propofol/
propofol regimen, giving an ICER of £46.1 per
PONV episode avoided for this comparison.
Table 36 summarises the ICERs for propofol/
propofol and propofol/sevoflurane when they
are each compared to the least costly and least
effective (propofol/isoflurane) regimen.
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