In people with bone marrow disorders bleeding can be a problem due to a low platelet count, or because the platelets do not work properly, or both. Platelet transfusions can be given when bleeding occurs in order to stop the bleeding, or before bleeding occurs in order to prevent it.
In this review we investigated whether transfusions should be given only when bleeding occurs, or in advance as a preventative measure. Our target population was people of any age with bone marrow disorders.
The bone marrow is where many types of blood cells are produced. Red blood cells are needed to bring oxygen to all parts of the body; white blood cells fight against infection; and platelets in the blood help to form clots and prevent bleeding. Bone marrow failure can have different causes and can happen at birth or later in life, and may result in too few of any or all of the three types of blood cells in the body.
Too few platelets can put a person at risk of serious or life-threatening bleeding. Platelet transfusions have been commonly used to prevent or treat bleeding in people with bone marrow disorders. However, there are risks involved with regular use of platelet transfusions, such as transfusion reactions and transfusion-transmitted infections.
It is currently unclear if the best transfusion policy is to give platelet transfusions only when bleeding occurs or to give them to prevent bleeding.
We searched scientific databases for clinical studies (randomised controlled trials and well-designed non-randomised studies) of people of any age with bone marrow disorders and a low platelet count. The evidence is current to 12 October 2017. One study was eligible for inclusion in the review. This study was stopped after recruiting only nine participants because it had taken three years to recruit the nine participants (the study had planned to recruit 60 participants in two years). We found no ongoing studies.
The only included study in this review did not report any outcomes.
We found no evidence to help us decide whether giving platelet transfusions to treat bleeding is as good as giving platelet transfusions when the platelet count is below a prespecified level. There is an urgent need for good-quality studies to answer the questions of this review.
Quality of evidence
We did not assess the quality of the evidence because no data were available from the one included study.
We found no evidence to determine the safety and efficacy of therapeutic platelet transfusion compared with prophylactic platelet transfusion for people with long-term bone marrow failure disorders. This review underscores the urgency of prioritising research in this area. People with bone marrow failure depend on long-term platelet transfusion support, but the only trial that assessed a therapeutic strategy was halted. There is a need for good-quality studies comparing a therapeutic platelet transfusion strategy with a prophylactic platelet transfusion strategy; such trials should include outcomes that are important to patients, such as quality of life, length of hospital admission, and risk of bleeding.
Bone marrow disorders encompass a group of diseases characterised by reduced production of red cells, white cells, and platelets, or defects in their function, or both. The most common bone marrow disorder is myelodysplastic syndrome. Thrombocytopenia, a low platelet count, commonly occurs in people with bone marrow failure. Platetet transfusions are routinely used in people with thrombocytopenia secondary to bone marrow failure disorders to treat or prevent bleeding. Myelodysplastic syndrome is currently the most common reason for receiving a platelet transfusion in some Western countries.
To determine whether a therapeutic-only platelet transfusion policy (transfusion given when patient is bleeding) is as effective and safe as a prophylactic platelet transfusion policy (transfusion given to prevent bleeding according to a prespecified platelet threshold) in people with congenital or acquired bone marrow failure disorders.
We searched for randomised controlled trials (RCTs), non-RCTs, and controlled before-after studies (CBAs) in the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2017, Issue 9), Ovid MEDLINE (from 1946), Ovid Embase (from 1974), PubMed (e-publications only), the Transfusion Evidence Library (from 1950), and ongoing trial databases to 12 October 2017.
We included RCTs, non-RCTs, and CBAs that involved the transfusion of platelet concentrates (prepared either from individual units of whole blood or by apheresis any dose, frequency, or transfusion trigger) and given to treat or prevent bleeding among people with congenital or acquired bone marrow failure disorders.
We excluded uncontrolled studies, cross-sectional studies, and case-control studies. We excluded cluster-RCTs, non-randomised cluster trials, and CBAs with fewer than two intervention sites and two control sites due to the risk of confounding. We included all people with long-term bone marrow failure disorders that require platelet transfusions, including neonates. We excluded studies of alternatives to platelet transfusion, or studies of people receiving intensive chemotherapy or a stem cell transplant.
We used the standard methodological procedures outlined by Cochrane. Due to the absence of evidence we were unable to report on any of the review outcomes.
We identified one RCT that met the inclusion criteria for this review. The study enrolled only nine adults with MDS over a three-year study duration period. The trial was terminated due to poor recruitment rate (planned recruitment 60 participants over two years). Assessment of the risk of bias was not possible for all domains. The trial was a single-centre, single-blind trial. The clinical and demographic characteristics of the participants were never disclosed. The trial outcomes relevant to this review were bleeding assessments, mortality, quality of life, and length of hospital stay, but no data were available to report on any of these outcomes.
We identified no completed non-RCTs or CBAs.
We identified no ongoing RCTs, non-RCTs, or CBAs.