Biology Reference
In-Depth Information
patients who did not receive their PAD until their hemoglobin concentration
was <9 g/dL (p < 0.002). The immediate transfusion of the PAD was suggest-
ed to be particularly critical for elderly patients undergoing total knee arthro-
plasty because they have an increased risk of cardiac and non-surgical com-
plications and increased hemoglobin level is thought to improve outcome.
One concern noted by other authors is an observed decrease in the pre-oper-
ative blood values secondary to a PAD program [22, 24]. In addition, a one- to
two-unit PAD program did not cause a significant erythropoietic response;
therefore anemia was noted before surgery. Post-surgical transfusions may not
always result in the desired hemoglobin concentrations because stored autolo-
gous units may contain suboptimal numbers of red blood cells.
We recently evaluated our PAD program. Between 1993 and 1995, two units
of PAD were obtained on average compared with years between 1995 and
1997 when one unit was obtained. Our study showed a 3% decrease in hema-
tocrit values for every unit donated before surgery. While the hematocrit val-
ues were similar with one- and two-unit protocols, increased wastage was
noted in the two-unit PAD program [22].
We reviewed our results of the one-unit PAD program with automatic infu-
sion of the donated unit and found it to be the best procedure for PAD. All
patients were to be given their PAD immediately after surgery, the best plan for
a PAD program. Despite ordering the PAD unit one month before surgery,sig-
nificant anemia was noted. A 1.3 g/dL decrease was noted between pre-dona-
tion and pre-surgical testing (data on file). As documented by others as well
[27, 28], the use of PAD resulted in anemia; patients did not return to their pre-
donation hemoglobin and hematocrit values. Although the allogeneic transfu-
sion rate was low, we feel that this reflects the acceptance of lower parameters
for hemoglobin concentration and hematocrit rather than the efficacy of a one-
unit PAD program. Had historical transfusion treatment been followed (hemo-
globin concentration <10 g/dL), a transfusion rate of 38.1% would have been
found. It should also be noted that 15% of patients were discharged with
hemoglobin concentrations <9 g/dL. The acceptance of lower hemoglobin
concentrations has a role in the lower allogeneic rates, not the efficacy of the
one-unit PAD program.
The protocol was based on the work of Lotke et al. [30], showing fewer
medical complications with the actual infusion of the donated unit. Our insti-
tution has since abandoned the above protocol based on its apparent lack of
efficacy. This protocol may also place patients at risk,since a 100% autologous
rate exposes them to donation error. Goldman et al. [31] revealed autologous
error rates in Canada, and found an error rate of 6/149. Not all of these errors
were related were to labeling (48%) or component preparation (25%). One
patient received the wrong unit of donated blood, an event that is common. The
College of American Pathologists noted 0.9% of 3,852 institutions studied, had
at least one unit of PAD given to the wrong patient [32].
Cost is also an issue for PAD, for this is not an inexpensive procedure, with
many costs related to procurement, as well as costs connected with the 50% to
