Blood, 1960, Vol. 16, No. 6, pp. 1669-1692.
© 1960 American Society of Hematology, Inc.
The Viability of Stored Human Platelets
MARIO BALDINI 1,
NICHOLAS COSTEA 1,
WILLIAM DAMESHEK 1, and
ALVERA LIMAURO 1
1 Blood Research Laboratory, a unit of the Ziskind Laboratories, New England
Center Hospital, Boston, Mass., and the Department of Medicine, Tufts University School
of Medicine.
Viability of normal human platelets preserved for short intervals at 4 C. was
studied by in vitro labelling with Na2Cr51O4. As a criterion of viability two
parameters were used: (1) the survival time of the infused platelets, and (2)
the maximum percentage of platelet radioactivity which could be recovered
in the circulation after infusion. From these two parameters the platelet viability index was calculated, and for stored platelets this was expressed in per
cent of the value obtained with freshly prepared platelets.
After 3 hours of storage at 4 C. the platelet viability index was reduced to
62 per cent. With longer periods of storage the viability of the platelets fell
rapidly with viability indices of 12 per cent after 24 hours and 2 per cent after
48 hours. No significant difference was seen whether the platelets were stored
as whole blood, as platelet-rich plasma, or as platelet concentrates suspended
in a plasma medium. When stored in saline the platelets lost their viability
more rapidly and the viability index was less than 5 per cent after only 24 hours.
When the platelets were stored for 24 hours in a DAS-gelatin medium, their
viability fell to insignificant levels within 24 hours.
Platelets frozen in glycerol-plasma and stored for 24 hours at —75 C. showed
reduction of viability to one-fifth the value obtained with fresh, unfrozen platelets. Even without storage the frozen platelets showed similar values of viability.
From these results the following conclusions may be drawn:
1. Conventional methods of storage at 4 C. result in rapid loss of platelet
viability. An inverse, almost logarithmic, relationship exists between time of
storage at 4 C. and platelet viability. The glycerol-freezing technique, although
better than most available methods, induces a great loss in platelet viability.
2. At present no method can be advised by which platelets can be preserved
in viable form even for relatively short periods of time. However, it is important to know that in the absence of plasma, platelet viability is lost more
rapidly than in a plasma medium.
3. From the data obtained, it seems advisable for the practice of platelet
transfusion to infuse platelets within less than 3 hours after collection.
4. Methods of improving the viability of stored blood platelets based upon
their metabolic needs are strongly warranted and are now under study.
Submitted on June 6, 1960
Accepted on July 13, 1960
