Platelet transfusion

    • Platelet poster

      Platelet product description and storage

      A variety of platelet products are produced by ARCBS in Victoria.

      Apheresis Paediatric Leucocyte Depleted  (split into 4 or 8 parts)

      These platelets are collected from a single donor via apheresis and are suspended in plasma.
      Volume: 40-60mL (actual volume is specified on the label)
      Platelet Count: >60 x 109/unit
      White Cell Count: < 1.0 x 106/unit
      These platelets are suitable for neonatal and paediatric use (see table for appropriate dose)

      Pooled platelets

      An adult dose of platelets derived from whole blood is obtained from a pool of buffy coats from four ABO identical donors and is resuspended in a nutrient additive solution to produce a pooled platelet component
      Volume: >160mL (actual volume is specified on the label)
      Platelet Count: >240 x 109/pool
      White Cell Count: < 1.0 x 106/pool
      These platelets are suitable for adults and paediatric patients > 40kg.

      Platelet Apheresis Leucocyte Depleted
      These platelets are collected from a single donor via apheresis and are suspended in plasma.
      Volume: >100 (actual volume is specified on the label)
      Platelet Count: >240 x 109/unit
      White Cell Count: < 1.0 x 106/unit
      These platelets are suitable for adults and paediatric patients > 40kg.

      All platelets produced in Victoria are;

      • Irradiated to prevent Ta-GVHD
      • Leucocyte depleted 

      Important Note:

      In times of product shortage, platelets may be sourced from interstate and may not be leucocyte depleted. It is therefore imperative to read the label on every product.  
       

      Storage and Shelf Life

      Platelets are stored at 20-240C on a platelet agitator for a period of 5 days from collection. (Do not refrigerate).

      Platelet expiry is at midnight on the date specified on the platelet pack.

      Platelet Product Selection

      Product and Dose?

      PLATELET PRODUCT

      <10kg1

      10-20kg

      20-30kg

      30-40kg

      >40kg

      Pooled platelets (Adult unit)

      5 - 10 ml/kg


      5 - 10 ml/kg


      5 - 10 ml/kg


      1 unit or 10 ml\kg

      Whichever is less

      1 unit

      Apheresis platelets (Adult unit)

      5 - 10 ml/kg

      5 - 10 ml/kg

      5 - 10 ml/kg

      1 unit or 10 ml/kg

      Whichever is less

      1 unit

      Paediatric apheresis platelets (pedipak)

      1 pedipak or 5 - 10 ml/kg

      Whichever is less

      2 pedipaks or 5 - 10 ml/kg

      Whichever is less


      3 pedipaks or 5 - 10 ml/kg

      Whichever is less


      4 pedipaks or 5 - 10 ml/kg

      Whichever is less


      NO


      • If a pedipak is not available, and platelet transfusion is required, transfuse using an adult unit at a dose of 5-10 ml/kg given over 2-3 hours.
      • In some patients, limiting donor exposure to prevent alloimmunisation is vitally important eg severe aplastic anaemia. In these patients, an apheresis product should be selected when it is available, rather than a pooled product or multiple individual products

      Blood Group

      Principles

      • ABO and Rh(D) identical platelet transfusion is ideal, but not always available.
      • Platelets collected from Rh(D) positive donors should be avoided for Rh(D) negative, non-immunosuppressed recipients. The small number of contaminating red cells may be sufficient to cause Rhesus immunisation. If transfusion of RhD positive product to RhD negative recipient is unavoidable, consider giving Rhesus immunoglobulin (Discuss with haematologist-on-call)
      • Avoid incompatible plasma. Transfusing platelets from group O donors to group A, B or AB recipients may result in haemolysis (from anti-A and anti-B in group O plasma). Children and infants are more at risk than adults due to their small blood volume. If ABO incompatible transfusion is unavoidable, the use of pooled platelets in additive solution (T-Sol) may reduce the risk of haemolysis.


      Patient's ABO Group

      Platelet Product Group

      First Choice

      Second Choice

      Third Choice

      O

      O

         

      A

      A

      B

      O

      B

      B

      A

      O

      AB

      AB

      B or A

      O

      Special platelet products and how to access them

      Platelets for Fetomaternal Alloimmunisation 

      The infant or fetus with confirmed or suspected alloimmune thrombocytopenia should be transfused platelets which are negative for the implicated alloantigen. Platelets negative for the HPA-1a antigen (implicated in 85% of cases of FMAIT in Caucasian populations) are often available from ARCBS but may be sourced from interstate. Contact the haematologist-on-call for advice regarding platelet support in this clinical situation.

      Platelets for HLA immunised refractory patients

      When patients fail to achieve a significant and sustained rise in the platelet count following platelet transfusion (platelet increment) they are said to be 'refractory'. There are clinical and immunological causes of platelet refractoriness. Clinical causes include fever, sepsis, bleeding, DIC and some drugs. In these situations, patients may respond to more frequent platelet transfusions or higher doses of platelets. Patients undergoing stem cell transplantation, who are multiply transfused, or who have had prior pregnancy may become refractory to platelet transfusion due to the development of multispecific HLA or platelet-specific antibodies. These patients may require platelet support from HLA (Human Leucocyte Antigen) or HPA (Human Platelet Antigen) matched donors. 

      Tests Required to diagnose immunological platelet refractoriness

      HLA Typing

      HLA/HPA Antibodies

      Ordering Matched Platelets for Refractory Patients

      If HLA or HPA matched apheresis platelets are required, please contact the RCH Blood Bank, ph 55829.

      Platelet administration

      The patient should be ready for transfusion prior to picking up platelets from the blood bank. eg appropriate IV access, written order for transfusion. A Blood Bank Release Order is required for all products to be picked up from the blood bank, refer to issue of blood products from the blood bank.

      Administer via Standard 170-200 micron filter either in-line or on transfer to syringe.

      Suitable products include:

      •  170 - 200 micron in-line blood filter set
      • Tuta Blood/Solution Administration Pump Set
      • Baxter Neonatal Set 

      Use a fresh administration set for platelets. Do not transfuse though a standard filter straight after red cells as platelets will get caught up in fibrin strands /debris etc.

      All platelet products issued from Red Cross Victoria are leucocyte depleted as indicated on the product label.

      As for all blood products adhere to pre-transfusion check and care and monitoring of transfused patients, refer to Blood Administration

      Rate: Platelet transfusion must be completed within 4 hours of spiking pack. Occasionally platelets are given over 30 minutes, but this may contribute to an increased risk of some reactions (fever/chill) and fluid overload.

      In patients receiving multiple other fluids etc give at a rate of 3ml/kg/hr over 2-3 hours.

      Adverse effects of platelet transfusion

      See section on adverse effects of transfusion.

      Platelet products are collected from volunteer donors screened with standard screening tests and have the same risks of infectious disease transmission as red cell products.

      Some adverse reactions may occur more commonly with platelet transfusion.
      These include:

      • Febrile (fever/chill) Reactions
      • Bacterial Contamination
      • Transfusion Related Acute Lung Injury

      Clinical information and indications for platelet transfusion

      Guidelines for platelet transfusion in children 

      Oncology

      • Platelet count <10 x 109/L - Chemotherapy and haemopoetic stem cell transplantation
      • Platelet count <20 x 109/L - Chemotherapy, haemopoetic stem cell transplantation and risk factors (fever, minor bleeding)
      • Platelet count <50 x 109/L - Lumbar puncture and new disease induced thrombocytopenia
      • Platelet count <30 x 109/L - Lumbar puncture and ongoing chemotherapy induced thrombocytopenia

      Invasive procedures

      • Platelet count <50 x 109/L - Patient undergoing invasive procedure
      • Platelet count <100 x 109/L - Patient undergoing high risk invasive procedure (e.g. neurosurgery)

      Critically ill patients (limited evidence, suggested thresholds. NB: higher transfusion triggers may be acceptable in certain circumstances)

      • Platelet count <10 x 109/L - No bleeding
      • Platelet count <20 x 109/L - No bleeding and risk factors (e.g. sepsis, renal failure, medications)
      • Platelet count <100 x 109/L - Extra corporeal life support (ECLS) however lower platelet count may be acceptable in some patients.

      Active bleeding - Platelet count <50 x 109/L

      Neonatal thrombocytopenia - <30 - 50 x 109/L (See table below for further information)

      Platelet transfusion in children with malignant disease

      Children with leukaemia are the largest single group of patients receiving platelet transfusions. Platelet transfusion is used therapeutically in patients with bleeding and significant thrombocytopenia.

      Prophylactic platelet transfusion is not routinely used during induction therapy for Acute Lymphoblastic Leukaemia or for solid tumours (with the exception of brain tumours) unless patients are symptomatic, there is active bleeding, an invasive procedure or additional risks such as fever.

      Prophylactic platelet transfusion during induction chemotherapy for Acute Myeloid Leukaemia using a threshold of 10 x 109/L and during the pre engraftment phase of stem cell transplantation using a threshold of 20 x 109/L is widely practised.

      A number of studies show that bleeding is more likely to arise in disease-induced than therapy-induced thrombocytopenia, and the presence of additional risk factors such as sepsis, drugs that impair platelet function, abnormal haemostasis or invasive procedures increase the risk of bleeding and a higher threshold is recommended. A platelet count above 30-50 x 109/L is generally acceptable for lumbar puncture, above 50 x 109/Lfor minor surgery and above 80-100 x 109/L for major surgery such as neurosurgery.

      Platelet Transfusion in Stem Cell Transplantation

      In the absence of evidence-based guidelines for children, the following clinical circumstances represent acceptable indications for platelet transfusion in stem cell recipients.

      Prophylactic platelet transfusion during the pre engraftment phase of stem cell transplantation using a threshold of 20 x 109/L.

      A higher threshold may be used in the presence of bleeding, severe mucositis, coagulopathy or concurrent anticoagulation.

      ABO incompatibility between the patient and stem cell donor may be major, minor or both. In major incompatibility, the recipient has antibodies to the stem cell donor's red cells (eg group A donor and group O recipient); in minor incompatibility the stem cell preparation from the donor has antibodies to recipient red cells (eg anti-A in group O donor and group A recipient); in both major and minor incompatibility, the recipients plasma contains antibodies to the donor's cells and the donor plasma contains antibodies to the recipient's cells (eg group B recipient and group A donor).

      Platelets for Stem Cell Recipients

      Where possible, a platelet product compatible with both donor and recipient should be used. At RCH the platelet product choice for each transplant recipient will be specified by their transplant physician and will be listed the Transplant Protocol. 

      Platelet transfusion in children with congenital platelet disorders

      There are several inherited platelet disorders that occasionally require platelet transfusions. Platelet transfusion has been shown to be of benefit in Bernard-Soulier syndrome and Glanzmann's thrombasthenia to cover surgery or a bleeding episode. Platelet transfusion can provoke the development of multi-specific HLA or platelet specific antibodies and they should be used sparingly. Donor exposure should be limited through the use of apheresis platelets and the risk of alloimmunisation reduced through the use of leukocyte reduced products.

      Platelet transfusion in defects of platelet production

      There are many rare causes of defects in platelet production such as thrombocytopenia with absent radii (TAR), Wiskott-Aldrich syndrome, Fanconi anaemia, amegakaryocytic thrombocytopenia. Platelet transfusion should be used sparingly and reserved for clinical bleeding or invasive procedures since many patients with these conditions will require stem cell transplantation.

      Platelet transfusion in immune thrombocytopenia

      Transfused platelets are rapidly destroyed and should be reserved for cases of life-threatening bleeding.

      Platelet transfusion in cardiopulmonary bypass and ECMO

      Platelet transfusion may be warranted in the patient with unexplained excessive bleeding undergoing cardiopulmonary bypass. Patients undergoing ECMO are usually transfused to maintain a platelet count > 100 x 109/L.

      Guidelines for Platelet Transfusion in Neonates

      Asymptomatic thrombocytopenia
      - Stable term or preterm infant consider if platelet count < 20-30 x 109/L
      - Sick term or preterm infant consider if platelet count less than 30-50 x 109/L

      Symptomatic thrombocytopenia in any neonate
      - Major organ bleeding and platelet count < 100 x 109/L
      - Minor bleeding and platelet count < 50 x 109/L

      Thrombocytopenia and invasive procedures
      - Surgery: consider if platelet count < 50 x 109/L
      - Exchange transfusion: consider if platelet count < 50 x 109/L

      Thrombocytopenia and DIC
      - Consider if platelet count < 50 x 109/L 

      Thrombocytopenia is the most common haemostatic abnormality in sick newborn infants. The immature coagulation system in neonates contributes to an increased bleeding risk. Platelet transfusions are indicated for the support of selected neonates with clinically significant quantitative or qualitative platelet disorders. Consideration should be given to the cause and natural history of the thrombocytopenia, as this may alter the type of platelet product given.

      In the only reported randomised controlled study of platelet transfusion in preterm infants, Andrew et. al. found no benefit (defined as the reduction of significant haemorrhage) in babies where moderate thrombocytopenia (50-150 x 109/L) was prevented by platelet transfusion compared to control babies.

      Guidelines for platelet transfusion in the neonate acknowledge the lack of evidence on which to make recommendations and aim for a safe approach. Experience from allo-immune thrombocytopenia indicates that in a well term neonate, the risk of significant haemorrhage as a result of thrombocytopenia is unlikely at counts above 30 x 109/L, however for preterm infants, despite the lack of evidence, a higher threshold of 50 x 109/L is recommended.

      Fetomaternal Alloimmune Thrombocytopenia (FMAIT)

      FMAIT is a serious disease capable of causing significant morbidity or mortality from haemorrhage in-utero or during the perinatal period. Intracerebral haemorrhage (ICH) secondary to severe thrombocytopenia has been reported as early as 18 weeks gestation. The level of thrombocytopenia which places the fetus at risk is not known, but ICH has rarely been reported in neonates with platelet counts greater than 30 x 109/L. Weekly or fortnightly platelet transfusion given in-utero have been used to reduce the risk of ICH, however others recommend maternal IVIG to raise the fetal platelet count. Appropriate antigen-negative platelets should be available to be given to a fetus undergoing any invasive procedure such as cordocentesis.

      For the neonate with FMAIT, platelet transfusion is the treatment of choice and should be given to normalise the platelet count in an infant with ICH or to treat severe throbmobocytopaenia in infants without ICH. Platelets used for neonates with FMAIT should be negative for the implicated platelet-specific antigen. Maternal platelets which have been plasma-reduced and irradiated are sometimes used.

      Congenital infections

      Neonates born with CMV infection, rubella, toxoplasmosis, syphilis or herpes simplex may have suppression of thrombopoiesis and/or splenomegaly with shortened platelet survival. Mild to moderate thrombocytopenia may be present. This usually does not require platelet support.

      Neonates of mothers with immune thrombocytopenia (ITP)

      Neonatal thrombocytopenia may be associated with past or current maternal ITP. The majority of infants are only mildly affected and the thrombocytopenia resolves spontaneously Severe thrombocytopenia is reported to occur in a approximately 4% of neonates and the incidence of ICH is extremely low. Intravenous immunoglobulin and steroids are the treatments of choice where the thrombocytopenia is severe or bleeding is present.

      Intrauterine platelet transfusion

      Intrauterine transfusion (IUT) of platelets is used to correct fetal thrombocytopenia caused by platelet alloimmunisation. IUT of platelets is used to correct fetal thrombocytopenia and reduce the risk of cord haemorrhage during fetal blood sampling procedures and is used as therapy to prevent intracerebral or other major haemorrhage in some cases of alloimmune thrombocytopenia. IUT is used to maintain an acceptable fetal platelet count while enabling the pregnancy to advance to a gestational age where the risks of prematurity are less than the risks of ongoing pregnancy, and with as few invasive procedures as possible. IUT is associated with a risk of fetal loss estimated at approximately 1%.

      Platelet Transfusion in pregnancy

      Thrombocytopenia is not uncommon during pregnancy, and the majority of women with mild to moderate thrombocytopenia do not require platelet transfusion. Platelet transfusion is virtually never required for gestational thrombocytopenia, and rarely required in ITP. The most common clinical situations requiring platelet support in pregnancy include; thrombocytopenia occurring in the setting of major post partum haemorrhage, DIC or placental abruption, or in the setting of severe pre-eclampsia or HELLP (Haemolysis, Elevated liver enzymes and Low Platelets) Syndrome.

      Pregnant women who are CMV negative or CMV status unknown should receive CMV seronegative platelets