Controversy concerning platelet dose

The highest level of support for evidence based decisions is the randomized controlled trial (RCT); however, RCT results are only useful if the study has strong internal and external validity. There have been a number of clinical trials that have addressed the issue of the optimal platelet dose; however, none of these studies have provided definitive data on the optimal platelet dose due to a variety of methodological issues associated with the study designs. Currently two randomized controlled trials have been implemented to address the issue of optimal platelet dose. The results of these trials will not be available until 2007–2008. The BEST (Biomedical Excellence for Safer Transfusion) Collaborative has initiated a platelet dose study comparing the frequency of WHO bleeding Grade 2 with low and standard dose platelets. The Transfusion Medicine/ Haemostasis Clinical Trials Network (CTN) is also performing a platelet dose study comparing three treatment strategies (high, standard and low dose platelets). There were numerous methodological issues that had to be considered when designing these two studies. More recently some European investigators have questioned the need for prophylactic platelet transfusions and several studies are currently underway to investigate the efficacy of changing this practice.