BACKGROUND: Standards and regulations require measurement of pH as an apheresis platelet (PLT) component quality monitor. The usefulness of this quality control (QC) measure was investigated. STUDY DESIGN AND METHODS: QC data were retrospectively reviewed for apheresis PLTs collected over 4.5 years. Three collection devices were used, the Amicus (Baxter), the CS-3000 Plus (Baxter), and the MCS+ LN9000 (Haemonetics). Each month, four components from each instrument were sampled. PLT counts and component volume were measured immediately after collection, and pH, after 5 days of storage. RESULTS: A total of 668 products were studied. pH decreased as PLT concentration increased (r(2) = 0.129, p < 0.001) and as component volume decreased (r(2) = 0.086, p = 0.02). PLT concentration and volume, however, were poor predictors of a low pH. Apheresis instrument type affected pH. The 216 components collected with use of the CS-3000 device had a lower pH than components from the other two instruments. Only 13 components had a pH value less than the acceptable level of 6.2, 12 of which were collected with the CS-3000. CONCLUSIONS: For newer-model blood cell separators, pH measurements do not provide information that might identify a manufacturing problem. Because factors that influence pH are controlled or monitored for each component, evaluation of pH on a sample group provides an indication of the quality of specific component only, rather than an effective monitor of the quality of the manufacturing process.
BACKGROUND: Standards and regulations require measurement of pH as an apheresis platelet (PLT) component quality monitor. The usefulness of this quality control (QC) measure was investigated. STUDY DESIGN AND METHODS: QC data were retrospectively reviewed for apheresis PLTs collected over 4.5 years. Three collection devices were used, the Amicus (Baxter), the CS-3000 Plus (Baxter), and the MCS+ LN9000 (Haemonetics). Each month, four components from each instrument were sampled. PLT counts and component volume were measured immediately after collection, and pH, after 5 days of storage. RESULTS: A total of 668 products were studied. pH decreased as PLT concentration increased (r(2) = 0.129, p < 0.001) and as component volume decreased (r(2) = 0.086, p = 0.02). PLT concentration and volume, however, were poor predictors of a low pH. Apheresis instrument type affected pH. The 216 components collected with use of the CS-3000 device had a lower pH than components from the other two instruments. Only 13 components had a pH value less than the acceptable level of 6.2, 12 of which were collected with the CS-3000. CONCLUSIONS: For newer-model blood cell separators, pH measurements do not provide information that might identify a manufacturing problem. Because factors that influence pH are controlled or monitored for each component, evaluation of pH on a sample group provides an indication of the quality of specific component only, rather than an effective monitor of the quality of the manufacturing process.