Disorder of platelets, hemostasis, and coagulation Flashcards
What is hemostasis?
The body’s process of stopping bleeding! 🩸🔧
What are the two phases of hemostasis?
✔️ Primary Hemostasis – Platelets stick together like “first responders” 🚑
✔️ Secondary Hemostasis – Clot forms with fibrin (“the glue”) 🏗️
What are the two major problems with hemostasis?
🚨 Excessive bleeding (Blood won’t clot properly)
⚠️ Excessive clotting (Blood clots too easily, causing blockages)
Where do platelets come from?
Megakaryocytes in the bone marrow make platelets!
What is the lifespan of platelets?
7–10 days
Stored in the spleen 🏦
What is the normal platelet level?
150,000–400,000 per microliter of blood
✔️ Too few? → Thrombocytopenia (Less than 100,000) 🚨
✔️ Too many? → Thrombocytosis (More than 750,000) ⚠️
What are the two pathways for clotting?
✔️ Intrinsic Pathway – Damage inside the blood vessel 🏥
✔️ Extrinsic Pathway – Damage outside the blood vessel (like a cut) ✂️
What do both pathways lead to?
The final common pathway!
✔️ Factor X gets activated → Prothrombin converts to thrombin →
✔️ Thrombin converts fibrinogen to fibrin → Clot forms! 🩸🛠️
What is fibrinolysis?
The body’s process of breaking down a clot!
What does tPA do?
tPA (tissue plasminogen activator) converts plasminogen → plasmin
✔️ Plasmin dissolves the clot!
What is an emergency treatment for clot breakdown?
rtPA (Alteplase) – A drug that breaks clots fast!
What causes too many platelets?
✔️ Splenectomy (removal of spleen) 🏥
✔️ Bone marrow disorders (Thrombocytosis)
✔️ Inflammation, infection, cancer
⚠️ Risk? → Blood clots forming in arteries or veins!
What increases clotting risk?
✔️ Slow blood flow (Stasis) – Bedridden, airplane travel ✈️
✔️ Atrial fibrillation – Irregular heartbeat → blood pools in heart ♥️
✔️ Excess clotting factors – Estrogen, cancer cells
🚨 Risk? – Deep Vein Thrombosis (DVT), Pulmonary Embolism (PE)
What causes low platelets?
✔️ Bone marrow problems – Leukemia, radiation
✔️ Spleen traps too many platelets
✔️ Platelet destruction – Autoimmune diseases
🚨 Severe thrombocytopenia = BLEEDING RISK! (Under 20,000)
What affects platelet function?
✔️ Medications (Aspirin, NSAIDs, blood thinners like Warfarin)
✔️ Kidney disease, uremia
⚠️ Even normal platelet counts can cause bleeding if they don’t work!
What are the two main types of Hemophilia?
✔️ Hemophilia A – Missing Factor VIII (8️⃣)
✔️ Hemophilia B – Missing Factor IX (9️⃣)
🚨 X-linked disorder (mostly affects males!)
🚑 Treated with Factor VIII or IX replacement therapy!
What blood tests check clotting?
✔️ PT (Prothrombin Time) – Checks extrinsic pathway
✔️ INR (International Normalized Ratio) – Used to monitor Warfarin
✔️ aPTT (Activated Partial Thromboplastin Time) – Checks intrinsic pathway
🚨 If PT, INR, or aPTT are HIGH → Blood takes too long to clot!
What are antiplatelet drugs?
Drugs that prevent platelets from clumping!
✔️ Aspirin – Stops platelets from sticking together 🚫🩸
✔️ Clopidogrel (Plavix) – Used after heart attacks
What are anticoagulants?
Drugs that slow down clotting!
✔️ Heparin – Fast-acting, used in hospitals 🏥
✔️ Warfarin (Coumadin) – Used long-term, monitored with INR
✔️ Newer drugs: Apixaban, Rivaroxaban (Eliquis, Xarelto)
What are the antidotes for anticoagulants?
• Heparin overdose? – Protamine sulfate
• Warfarin overdose? – Vitamin K
What is ITP?
An autoimmune disease where the body attacks its own platelets!
What are the symptoms of ITP?
✔️ Common in kids after viral infections
✔️ Causes bruising, purpura (purple spots), and low platelet counts!
✔️ Treated with steroids, IV immunoglobulin (IVIG), and sometimes spleen removal!
What is HUS?
A disease caused by bacteria (E. coli O157:H7) that damages blood cells & kidneys!
What are the symptoms of HUS?
🚨 Bloody diarrhea
🚨 Anemia (destroyed RBCs)
🚨 Kidney failure!
✔️ Treatment: Supportive care (fluids, dialysis)
✔️ No antibiotics for Stx-HUS!
What is the mnemonic for platelet disorders?
🛡️ Platelet Disorders Mnemonic – “Low or Hyperactive!”
✔️ Low Platelets = Bleeding (ITP, aplastic anemia, leukemia)
✔️ Too Many Platelets = Clotting (Thrombocytosis, DVT, PE)
What is the clotting pathway hack?
🩸 Clotting Pathway Hack:
✔️ Intrinsic = “Inside” (PTT Test!)
✔️ Extrinsic = “External Trauma” (PT Test!)
What should you think if there is a bleeding risk?
🚨 Bleeding Risk? Think: “PLATE”
✔️ Platelet issues
✔️ Liver disease
✔️ Anticoagulants
✔️ Trauma
✔️ Excessive clot breakdown (Fibrinolysis too strong)
