Loading icon
Health Information Center

Heparin-induced Thrombocytopenia

Authors:
  • Cynthia M. Johnson, MA
Publication Type:

Condition

Heparin-induced Thrombocytopenia

(HIT; Heparin-induced Low Blood Platelet Count)

Definition

Thrombocytopenia means low blood platelet count. Platelets are a special type of blood cell. They help form clots so a person does not bleed too much.

Heparin is a blood thinner that lowers the risk of blood clots. Heparin-induced thrombocytopenia (HIT) is low blood platelet count caused by heparin. It can lead to too much blood clotting. Too much bleeding is rare.

Clot Formation.

Copyright © Nucleus Medical Media, Inc.

blood clot platelethttp://services.epnet.com/getimage.aspx?imageiid=79037903platelet.jpgplateletNULLjpgblood clot plateletNULL\\hgfiler1\intellect\images\platelet.jpgNULL14NULL2009-10-15196399Copyright © Nucleus Medical Media, Inc.

Causes

HIT is caused by platelets clumping due to an immune reaction to heparin. The clumping uses them up and lowers the count.

Risk Factors

Taking heparin is a risk for having HIT.

Symptoms

Symptoms of HIT are from blood vessels being blocked:

  • Pain or swelling in the legs
  • Chest pain
  • Problems breathing
  • Anxiety
  • Sweating
  • Fast, uneven heartbeats
  • Headache

Diagnosis

The doctor will ask about symptoms and past health. A physical exam will be done.

Blood tests will be done to check the platelet count.

Treatment

Treatment may include:

  • Stopping the use of heparin.
  • Blood thinners to lower the risk of blood clots.
  • Vitamin K antagonists (VKA) therapy—in people taking a VKA, it will be stopped and vitamin K will be given; the VKA will be started again when the person's platelet count is normal.
  • Platelet transfusion may be given to replace used up platelets if there is a lot of bleeding, but this is rare.

Prevention

To lower the risk of HIT:

  • Avoid heparin use.
  • Take other blood thinners.
RESOURCES:

CANADIAN RESOURCES:

CANADIAN RESOURCES:

References

  • Arepally GM. Heparin-induced thrombocytopenia. Blood. 2017;129(21):2864-2872.
  • Heparin-induced thrombocytopenia (HIT). EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/heparin-induced-thrombocytopenia-hit.
  • Heparin sodium. EBSCO Nursing Reference Center Plus website. Available at: https://www.ebsco.com/health-care/products/nursing-reference-center-plus.

Contributors

  • Dianne Scheinberg Rishikof MS, RD, LDN
Last Updated:
2023-03-01

(C) Copyright 2023 EBSCO Information Services

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.