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PA20.1-2 | Welcome to Normal Haemostasis
Learning Objectives
- Describe the vascular and platelet responses that form the primary platelet plug.
- Trace the coagulation cascade through the intrinsic, extrinsic, and common pathways, identifying which lab tests measure each arm.
- Explain thrombin's central role in haemostasis.
- Describe the cell-based model of coagulation as the physiologically accurate mental model.
- Outline the fibrinolytic system and the natural anticoagulant mechanisms that keep haemostasis in balance.
- Identify the vitamin K–dependent clotting factors and their clinical relevance.
INSTRUCTIONS
Haemostasis is the first concept that unlocks an entire cluster of bleeding and clotting disorders — platelet diseases, coagulopathies, and DIC — all taught in SDL 2–4. Understanding how the normal system works, and which lab test measures which arm of it, is the single most important foundation in haematopathology. Master this SDL before moving forward.
References
- Robbins & Cotran Pathologic Basis of Disease, 10th ed., Ch. 4 — Haemodynamic Disorders (textbook)
- Harsh Mohan Textbook of Pathology, 8th ed., Ch. 7 — Disorders of Haemostasis (textbook)
Version 2.0 | NMC CBUC 2024