Platelet Concentrates Stored in Plasma for 72 Hours at 22 °C Prepared from Buffycoats of Citrate-Phosphate-Dextrose Blood Collected in a Quadruple-Bag Saline-Adenine-Glucose-Mannitol System

Abstract

A method is described to prepare platelet concentrates from the buffycoat of citrate-phosphate-dextrose (CPD) blood in a closed four-bag system and to store the platelets in autologous plasma under sterile conditions. After separation of the blood into plasma, buffycoat and leukocyte- and thrombocyte-poor red cell concentrate, saline-adenine- glucose-mannitol (SAGM) was added to the red cells. Next the platelets were concentrated in plasma by a second centrifugation and were transferred to the 600-ml bag that previously contained the SAGM. The platelets were stored for 72 h at 22 °C on a platform rotator at 1 cycle per second. The mean volume of the platelet concentrates (n = 12) was 61 ml, with an average platelet content of 72 x 10^9. The mean leukocyte contamination was only 17 x 10^6 ; erythrocytes were not detected. The aggregation of the platelets with 1 µM of ADP was normal. After 72 h of storage, the mean pH was 7.1 ± 0.1. The P0(2) always remained above 17 mm Hg. No loss of thrombocytes had occurred during storage. The platelets had retained their discoid shape. The aggregation response to ADP had disappeared, however. The in vivo viability of the platelets was determined in 8 healthy volunteers. Autologous platelets, stored for 72 h at 22°C, were labeled with 51 Cr and reinfused [43 (±9)% recovery at 15 min after reinfusion]. The mean survival time in vivo of the platelets was 6.8 (±0.7) days. These experiments indicate that with the four-bag SAGM system leukocyte-poor platelet concentrates can be prepared which remain in optimal condition for at least 72 h. Moreover, a high amount of plasma is yielded and, with SAGM as additive, leukocyte- and plateletpoor red cell concentrates can be stored for 5 weeks.