Elektronisk udgave - Sundhedsstyrelsen

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Many studies of ANH reported an impressive reduction in blood
transfused. Closer examination suggested that these reductions in
blood exposure may be due to flawed study design.
Australian update (orthopedic, cardiac and other types of surgery)
24 trials – mostly in orthopedic and cardiac surgery – reported in 22 publications
(59, 147-167) included 1132 patients, of whom 595 were randomized to
ANH. The trials were very small, the majority having insufficient power to detect
a statistically significant benefit from ANH.
◆ Overall, ANH reduced the rate of transfusion of allogeneic blood by a
(relative) 34% (RR 0.66(0.53-0.82)).
◆ The absolute reduction of risk of allogeneic transfusion was 29.1%, and
on average 3 patients would have to undergo ANH so that one would
avoid allogeneic transfusion. (NNT 3.4 (2.3-6.8)).
◆ ANH used in the context of “miscellaneous” procedures appear to be associated
with a greater reduction of risk of allogeneic transfusion than
when it was employed in cardiac or orthopedic procedures.
◆ Blood savings: On average, there was a 1.76 unit (1.01-2.51) reduction
in the allogeneic blood requirement, and this did not vary according to
the type of surgery performed.
◆ Transfusion protocol: When ANH was employed in the context of a
transfusion protocol, the reduction in allogeneic transfusion rate (a relative
18%) was not significant. In comparison, when no transfusion protocol
was being used, ANH was associated with an approximate 48% in
reduction rate of allogeneic transfusion. The saving in allogenic blood
was under 1 unit when a transfusion protocol was used, compared with
3 units when no protocol was used.
Autotransfusion/CS
ISPOT-results (orthopedic and cardiac surgery)
There were 28 trials reported in 27 publications (148, 152, 168-
192) that recruited a total of 2061 patients of whom 1038 were
randomized to undergo autotransfusion/CS). The sample size of individual
trials varied from 24 to 232.
In orthopedic surgery there were 16 trials included. Seven of the
trials used autotransfusion/CS devices that wash salvaged blood (3
used postoperatively, 1 intraoperatively and 3 used for both) and 9
of the trials used devices that do not wash salvaged blood (all used
postoperatively).
❖ Autotransfusion/CS with devices that wash salvaged blood
(used intra- or/and postoperatively) decreased the proportion of
patients who received allogeneic transfusion by (relative) 61%
(RR 0.39 (0.30-0.51)) in orthopedic surgery.