Effect of storage time of platelet products on clinical outcomes after transfusion: a systematic review and meta-analyses.

BACKGROUND: Prolonged storage improves availability of platelet products but could also influence safety and efficacy. This systematic review and meta-analyses summarize and quantify the evidence of the effect of storage time of transfused platelets on clinical outcomes. METHODS: A systematic search in seven databases was performed up to February 2016. All studies reporting storage time of platelet products and clinical outcomes were included. To quantify heterogeneity, I² was calculated, and to assess publication bias, funnel plots were constructed. RESULTS: Twenty-three studies reported safety outcomes and fifteen efficacy outcomes. The relative risk of a transfusion reaction after old platelets compared to fresh platelets was 1·53 (95% confidence interval (CI): 1·04-2·25) (12 studies). This was 2·05 (CI:1·47-2·85) before and 1·05 (CI: 0·60-1·84) after implementation of universal leucoreduction. The relative risk of bleeding was 1·13 (CI: 0·97-1·32) for old platelets compared to fresh (five studies). The transfusion interval was 0·25 days (CI: 0·13; 0·38) shorter after transfusion of old platelets (four studies). Three studies reported use of platelet products: two for haematological patients and one for trauma patients. Selecting only studies in haematological patients, the difference was 4·51 units (CI: 1·92; 7·11). CONCLUSION: Old platelets increase the risk of transfusion reactions in the setting of non-leucoreduction, shorten platelet transfusion intervals, thereby increase the numbers of platelet transfusions in haematological patients, and may increase the risk of bleeding.

Effect of platelet storage time on platelet measurements: a systematic review and meta-analyses.

BACKGROUND: The storage time of platelet products negatively affects bacterial safety and platelet function. However, low maximum storage time increases outdating of valuable products. Thus, to quantify the effect of platelet storage time on platelet measurements after platelet transfusion, a systematic review and meta-analyses were performed. METHODS: Reports and meeting abstracts of randomized trials and observational studies, performed in humans, reporting platelet measurements after transfusion of platelet products of different storage times, were selected until February 2016. Meta-analyses were performed for four different storage time contrasts, each answering a different question. Random-effects models were used to account for substantial heterogeneity and the weighted mean differences calculated. RESULTS: Our search strategy yielded 4234 studies of which 46 papers satisfied the inclusion criteria. As judged by the 1-h corrected count increment, transfusions of fresher platelets compared to stored platelets showed better increment. The weighed mean difference varied from 2·11 (95%CI: 1·51-2·71) to 2·68 (95%CI: 1·92-3·45). For the 24-h corrected count increment, the weighted mean difference varied from 1·36 (95%CI: 0·12-2·60) to 1·68 (95%CI: 1·07-2·28) depending on the contrast. Recovery and survival of old platelets as percentage of fresh platelets were 81% and 73% for the original definition contrast. For the extended storage contrast, recovery and survival were 75% and 68%. CONCLUSIONS: Fresh platelets were superior to old platelets for all platelet measurements and for all storage time contrasts meta-analysed.

Clinical practice of platelet transfusions in haemato-oncology.

Platelets are prophylactically transfused to patients receiving myeloablative chemotherapy. The trigger can be adapted if a patient has risk factors for bleeding. We performed an international survey to quantify differences in transfusion policies. While platelet counts are most important, bleeding, fever, use of anticoagulants and invasive procedures also determine transfusion strategies. The largest variation of triggers was observed for lumbar punctures and removal of central venous catheters.