Hemostasis – What stops us from bleeding out.
Three main steps:
- Vasoconstriction
- Primary hemostasis (platelet plug) – the temporary way to stop bleeding
- Secondary hemostasis (clotting cascade) – the more permanent way
Bleeding disorders can be broadly divided into whether they affect platelet plug formation or the clotting cascade (if you need a refresher, click here)
| Platelet Disorder | Clotting Cascade Disorders |
| Immediate bleeding Muscosal and cutaneous Bruises and petechiae Nose bleeds (epistaxis) Menorrhagia (heavy periods) von Willebrand Thrombocytopenia DIC |
Delayed Bleeding Deep (muscles and joints) Palpable bruises, large spreading hematomas Hemarthrosis Post-surgical bleeding Hemophilia A (factor VIII) Hemophilia B (factor IX) Warfarin |
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