PLATELET TRANSFUSION

• To revise the principles of transfusion, see Principles of transfusion and Consent for transfusion guidelines
• Collected from UK volunteer whole blood and/or apheresis platelet donors
• Pooled buffy coat platelets (4 donors in ‘platelet additive solution’)
• mean volume 308 mL, mean platelets 308 x 10⁹/unit (165–500), <0.3 mL red cells
• Apheresis platelets
• mean volume 199 mL, mean platelets 280 x 10⁹/unit (165–510)
• Stored in controlled temperature 20–24°C with agitation for <7 days with bacterial screening
• There is no need to agitate platelets after removal from cold storage 

• Apply surface pressure and correct any surgical causes
• Review/stop anticoagulants/antiplatelet drugs
• Consider tranexamic acid
• Uraemia with bleeding – dialysis, correct anaemia, consider desmopressin
• Inherited platelet function disorders – consider desmopressin
• If fibrinogen <1.5 g/L with severe bleeding, replace. See Cryoprecipitate

• If in doubt, discuss with haematologist
• Assess WHO bleeding score
• In patients with inherited or acquired platelet disorders/abnormal platelet function, discuss transfusion with haematology first
• Platelet transfusion may be inferior to standard care in patients on anti-platelet agents with spontaneous intra-cerebral haemorrhage
• In some situations, target platelet thresholds may not be achievable
• individual case review is required

Prophylaxis (no bleeding/WHO bleeding score grade 1)

Reversible bone marrow failure (BMF) including stem cell transplantation

• Transfusion threshold: platelets ≤10 x 10⁹/L
• consider no prophylaxis in autologous stem cell transplantation 

Critical illness

• Transfusion threshold: platelets ≤10 x 10⁹/L

Chronic BMF receiving intensive therapy

• Transfusion threshold: platelets ≤10 x 10⁹/L

Chronic BMF to prevent persistent bleeding of grade ≥2

• Transfusion threshold: platelets count variable
• discuss with haematologist

Transfusion not indicated

• Chronic stable BMF (e.g. on low dose oral chemo or azacitadine)
• Abnormal platelet function
• Platelet consumption/destruction e.g. DIC, TTP
• Immune thrombocytopenia e.g. ITP, HIT, PTP

Prophylaxis in presence of risk factors for bleeding

• e.g. sepsis, antimicrobial treatment, abnormalities of haemostasis

Reversible BMF/chronic BMF on intensive therapy/critical illness

• Transfusion threshold: consider at platelets ≤20 x 10⁹/L

Transfusion not indicated

• Abnormal platelet function
• Platelet consumption/destruction e.g. DIC, TTP
• Immune thrombocytopenia e.g. ITP, HIT, PTP

Platelet transfusions pre-procedure

Central venous catheter insertion (excluding PICC)

• Transfusion threshold: platelets ≤20 x 10⁹/L

Lumbar puncture

• Transfusion threshold: platelets ≤40 x 10⁹/L

Percutaneous liver biopsy/ Major surgery

• Transfusion threshold: platelets ≤50 x 10⁹/L 

Epidural anaesthesia, insertion and removal

• Transfusion threshold: platelets ≤80 x 10⁹/L

Neurosurgery/ophthalmic surgery involving posterior segment of the eye

• Transfusion threshold: platelets ≤100 x 10⁹/L

Transfusion not indicated

• Bone marrow aspirate +/- trephine
• PICC line insertion
• Traction removal CVCs
• Cataract surgery

Therapeutic use (WHO bleeding grade ≥2)

Multiple trauma/Brain or eye injury/Spontaneous intracranial haemorrhage

• Transfusion threshold: platelets ≤100 x 10⁹/L

Severe bleeding

• Transfusion threshold: platelets ≤50 x 10⁹/L

Bleeding (WHO grade 2 but not severe)

• Transfusion threshold: platelets ≤30 x 10⁹/L

• Thrombotic thrombocytopenic purpura (TTP) unless life-threatening haemorrhage

• Dose platelets as 1 adult treatment dose (1ATD)
• prescribe on the fluid prescription of the drug chart
• Adult treatment dose of platelets is 1 ATD
• Each single ATD platelets transfused is a treatment decision
• Assess every patient for risk of transfusion associated circulatory overload (TACO)
• manage appropriately e.g. rate, diuretics, frequency of observations

• Transfuse as soon as possible after component arrives
• use a standard blood administration set with a 170–200 micron filter
• Do not transfuse platelets through an administration set that has already been used to administer red blood cells
• to avoid platelet clumping
• Check product for signs of deterioration/bacterial contamination before use
• e.g. clumping/discolouration, damage to bag
• Specify transfusion rate depending on clinical situation/patient history typically:
• if low risk of TACO, 20–30 min per ATD
• if high risk of TACO, 30–60 min per ATD
• if MHP, ‘stat’ over 5–10 min

• Assess patients clinically after each ATD for bleeding symptom severity and signs/symptoms of adverse events and TACO
• Assess laboratory parameters after each unit
• repeat FBC@≥15mins to assess if target platelet threshold achieved

Typical changes

• 1 ATD typically increases platelet count by 20–40 x 10⁹/L
• Platelet increment reduces with repeated platelet transfusions
• even in the absence of allo-immunisation
• Platelet increment in patients with chronic liver disease may be lower, but platelet activity is increased due to higher circulating von Willebrand factor