Thrombocytopaenia and Platelet Dysfunction in Critical Care
Description General measures Medicine treatment Referral ICD-10 code: D69.6 Description Qualitative and quantitative platelet disorders are common in critically ill patients and may be due to decreased production of platelets or increased consumption/sequestration. Common causes of thrombocytopaenia and/or platelet dysfunction include sepsis, blood loss, dilutional thrombocytopaenia, medica
ICD-10 code: D69.6
Description
Qualitative and quantitative platelet disorders are common in critically ill patients and may be due to decreased production of platelets or increased consumption/sequestration.
Common causes of thrombocytopaenia and/or platelet dysfunction include sepsis, blood loss, dilutional thrombocytopaenia, medical conditions (e.g. uraemia), and medications including antiplatelet drugs (e.g. aspirin and clopidogrel) and heparin.
- Heparin-induced thrombocytopaenia should be considered in a patient whose platelet count decreases by >50% within 5-10 days of initiating heparin, especially if thrombotic complications have also developed. If this occurs, STOP all heparin products and consult a specialist.
The decision to transfuse platelets depends on:
- Whether the patient is bleeding.
- Whether the patient is to undergo a procedure.
- Aetiology of the thrombocytopaenia.
- Patient’s platelet count.
- Results of coagulation testing.
Platelet transfusions are indicated in the following settings:
- Prophylactic: if platelet count <20 x 109 /L.
- A platelet count of <10 x 109 /L is an acceptable alternative if the patient is not septic, not bleeding, and has a slow decline in platelet count.
- Prophylactic prior to invasive procedures/surgery:
- Indicated if platelet count <50 x 109 /L. Alternative thresholds may be used for the following indications:
- Epidural catheter placement/removal: <75 x 109 /L.
- Neurosurgery or posterior ophthalmic surgery: <100 x 109 /L.
- Patients with intracranial haemorrhage: <100 x 109 /L.
- Indicated if platelet count <50 x 109 /L. Alternative thresholds may be used for the following indications:
- Empiric: in large volume blood transfusion (where more than 4 units of packed cells required).
- Therapeutic: if platelet count <50 x 109 /L and the patient is bleeding.
- Transfusion may be deferred in the presence of normal thromboelastography (where available).
General Measures
An assessment of haemostasis should be conducted with viscoelastic testing where available, e.g. thromboelastography (TEG), as this provides a functional assessment of whole blood clotting. A normal viscoelastic test may eliminate the need for a platelet transfusion even in the presence of thrombocytopaenia.
General measures to reduce bleeding in patients with thrombocytopaenia or platelet dysfunction include:
- Careful review of all anticoagulant and antiplatelet medication.
- Thorough assessment of other components of the coagulation system.
- Attention to maintaining normothermia and eucalcaemia.
Aspirin and clopidogrel are the most commonly used antiplatelet medications, and their antiplatelet effects may last up to 7 days. The need for platelet transfusions in the setting of platelet dysfunction should be discussed with a specialist.
Medicine Treatment
- Platelet cells, IV, one unit immediately.
- One unit of pooled platelets should be transfused at a time.
Note:
- The need for further platelet transfusions should be based on platelet count, viscoelastic testing (if available), and the presence or absence of ongoing bleeding.
Referral
- Heparin induced thrombocytopaenia: Consult a specialist.
- Platelet transfusions in the setting of platelet dysfunction: Consult a specialist.
Standard Treatment Guidelines and Essential Medicines List for South Africa Adult Hospital _Chapter 23: Adult Critical Care_NEMLC Medicine Recommendations Review Cycle_ 2020_2023