Annals of Internal Medicine CLINICAL GUIDELINE Platelet Transfusion: A Clinical Practice Guideline From the AABB Richard M. Kaufman, MD; Benjamin Djulbegovic, MD, PhD; Terry Gernsheimer, MD; Steven Kleinman, MD; Alan T. Tinmouth, MD; Kelley E. Capocelli, MD; Mark D. Cipolle, MD, PhD; Claudia S. Cohn, MD, PhD; Mark K. Fung, MD, PhD; Brenda J. Grossman, MD, MPH; Paul D. Mintz, MD; Barbara A. O’Malley, MD; Deborah A. Sesok-Pizzini, MD; Aryeh Shander, MD; Gary E. Stack, MD, PhD; Kathryn E. Webert, MD, MSc; Robert Weinstein, MD; Babu G. Welch, MD; Glenn J. Whitman, MD; Edward C. Wong, MD; and Aaron A.R. Tobian, MD, PhD Background: The AABB (formerly, the American Association of Recommendation 3: The AABB suggests prophylactic platelet Blood Banks) developed this guideline on appropriate use of transfusion for patients having elective diagnostic lumbar punc- platelet transfusion in adult patients. ture with a platelet count less than 50 × 109 cells/L. (Grade: weak recommendation; very-low-quality evidence) Methods: These guidelines are based on a systematic review of randomized, clinical trials and observational studies (1900 to Recommendation 4: The AABB suggests prophylactic platelet September 2014) that reported clinical outcomes on patients re- transfusion for patients having major elective nonneuraxial sur- ceiving prophylactic or therapeutic platelet transfusions. An ex- gery with a platelet count less than 50 × 109 cells/L. (Grade: pert panel reviewed the data and developed recommendations weak recommendation; very-low-quality evidence) using the Grading of Recommendations Assessment, Develop- Recommendation 5: The AABB recommends against routine ment and Evaluation (GRADE) framework. prophylactic platelet transfusion for patients who are nonthrom- Recommendation 1: The AABB recommends that platelets bocytopenic and have cardiac surgery with cardiopulmonary by- should be transfused prophylactically to reduce the risk for spon- pass. The AABB suggests platelet transfusion for patients having taneous bleeding in hospitalized adult patients with therapy- bypass who exhibit perioperative bleeding with thrombocytope- induced hypoproliferative thrombocytopenia. The AABB recom- nia and/or evidence of platelet dysfunction. (Grade: weak rec- mends transfusing hospitalized adult patients with a platelet ommendation; very-low-quality evidence) count of 10 × 109 cells/L or less to reduce the risk for spontane- Recommendation 6: The AABB cannot recommend for or ous bleeding. The AABB recommends transfusing up to a single against platelet transfusion for patients receiving antiplatelet apheresis unit or equivalent. Greater doses are not more effec- therapy who have intracranial hemorrhage (traumatic or sponta- tive, and lower doses equal to one half of a standard apheresis neous). (Grade: uncertain recommendation; very-low-quality unit are equally effective. (Grade: strong recommendation; evidence) moderate-quality evidence) Recommendation 2: The AABB suggests prophylactic platelet Ann Intern Med. 2015;162:205-213. doi:10.7326/M14-1589 www.annals.org transfusion for patients having elective central venous catheter For author affiliations, see end of text. 9 placement with a platelet count less than 20 × 10 cells/L. * This article was published online first at www.annals.org on 11 November (Grade: weak recommendation; low-quality evidence) 2014. pproximately 2.2 million platelet doses are trans- published evidence, about when platelet transfusion Afused annually in the United States (1). A high pro- may be appropriate in adult patients. For several com- portion of these platelet units are transfused prophylac- mon clinical situations, we attempted to identify a tically to reduce the risk for spontaneous bleeding in platelet count threshold below which platelet transfu- patients who are thrombocytopenic after chemother- sion may improve hemostasis and above which platelet apy or hematopoietic progenitor cell transplantation transfusion is unlikely to benefit the patient. We did not (HPCT) (1–3). Unlike other blood components, platelets attempt to address all clinical situations in which plate- must be stored at room temperature, limiting the shelf lets may be transfused, and these guidelines are not life of platelet units to only 5 days because of the risk intended to serve as standards. Clinical judgment, and for bacterial growth during storage. Therefore, main- not a specific platelet count threshold, is paramount in taining hospital platelet inventories is logistically diffi- deciding whether to transfuse platelets. cult and highly resource-intensive (4, 5). Platelet trans- fusion is associated with several risks to the recipient (Table 1), including allergic reactions and febrile non- TARGET POPULATION hemolytic reactions. Sepsis from a bacterially contami- These guidelines provide advice for adult patients nated platelet unit represents the most frequent infec- who are candidates for platelet transfusion. tious complication from any blood product today (8). In any situation where platelet transfusion is being consid- GUIDELINE DEVELOPMENT PROCESS ered, these risks must be balanced against the poten- tial clinical benefits. The AABB commissioned and funded the develop- ment of these guidelines. Panel Composition GUIDELINE FOCUS A panel of 21 experts was convened. Fifteen par- These guidelines were designed to provide prag- ticipants were members of the Clinical Transfusion matic recommendations, based on the best available Medicine Committee of the AABB, all of whom were © 2015 American College of Physicians 205 Downloaded from https://annals.org by Univ of California San Francisco user on 11/20/2019 CLINICAL GUIDELINE Platelet Transfusion: A Clinical Practice Guideline From the AABB Table 1. Approximate Per-Unit Risks for Platelet Grading of Evidence Transfusion in the United States The GRADE method was used to assess the quality of the evidence and determine the strength of recom- Adverse Event Approximate Risk per Reference mendations (13, 14). The recommendations were de- Platelet Transfusion veloped by consensus at an in-person panel meeting. Febrile reaction 1/14 6 Panel member judgments on 4 GRADE factors (quality Allergic 1/50 7 of evidence, balance between the intervention's bene- reaction Bacterial sepsis 1/75 000 8 fits and harms, resource use, and patient values and TRALI* 1/138 000 9 preferences) and ratings of the strength of recommen- HBV infection 1/2 652 580 Personal communication† dations were validated using an online survey tool 1 HCV infection 1/3 315 729 Personal communication† week after the meeting. HIV infection 0 (95% CI, 0 to 1/1 461 888) Personal communication† HBV = hepatitis B virus; HCV = hepatitis C virus; TRALI = transfusion- Definitions related acute lung injury. In this guideline, a platelet unit refers to 1 aphere- * The overall risk for TRALI from all plasma-containing blood products sis platelet unit or a pool of 4 to 6 whole blood–derived is currently estimated to be approximately 1/10 000 (10). 11 † Notari E, Dodd R, Stramer S. platelet concentrates, typically containing 3 to 4 × 10 platelets. Thrombocytopenia refers to a platelet count hematologists or pathologists with expertise in transfu- below the lower limit of the normal range used by the sion medicine. Five additional panel members included laboratory performing the count. Seven platelet trials a neurosurgeon, a cardiac surgeon, a critical care spe- included in the systematic review (15–21) used a varia- cialist, an anesthesiologist, and a hematologist, repre- tion of the World Health Organization scale (22) to as- senting the American Association of Neurological Sur- sess patient bleeding outcomes (23). A summary of the geons, the Society of Thoracic Surgeons, the Society of modified World Health Organization scale is provided Critical Care Medicine, the American Society of Anes- in Table 2. thesiologists, and the American Society of Hematology, respectively. The final panel member was a Grading of Recommendations Assessment, Development and CLINICAL RECOMMENDATIONS Evaluation (GRADE) methodologist. Committee mem- Clinical Setting 1: Hospitalized Adult Patients bers had no substantial conflicts of interest as defined With Therapy-Induced Hypoproliferative by the AABB conflict of interest policy. Pursuant to the Thrombocytopenia policy, individual members were required to disclose Recommendations actual and apparent financial, professional, or personal Recommendation 1: The AABB recommends that conflicts (Appendix Table 1, available at www.annals platelets should be transfused prophylactically to re- .org). duce the risk for spontaneous bleeding in adult patients with therapy-induced hypoproliferative Systematic Review of the Evidence thrombocytopenia. The guidelines were developed on the basis of a The AABB recommends transfusing hospitalized recent systematic review of the literature on platelet adult patients with a platelet count of 10 × 109 cells/L transfusions, published separately (11). The search or less to reduce the risk for spontaneous bleeding. strategy is provided in Appendix Table 2 (available at The AABB recommends transfusing up to a single www.annals.org). We searched PubMed from 1946 to apheresis unit or equivalent. Greater doses are not the first week of April 2013, and the Cochrane Central more effective, and lower doses equal to one half of a Register of Controlled Trials and Web of Science from standard apheresis unit are equally effective. 1900 to the first week of April 2013 (1024 studies iden- Quality of evidence: moderate;