Clinical meaning
Coagulopathies are disorders of hemostasis resulting in either excessive bleeding or thrombosis. Primary hemostasis (platelet plug formation) disorders include quantitative (thrombocytopenia) and qualitative (platelet dysfunction) platelet abnormalities, presenting with mucocutaneous bleeding (petechiae, purpura, epistaxis, GI bleeding). Secondary hemostasis (coagulation factor) disorders cause deep tissue bleeding (hemarthrosis, deep hematomas, delayed post-surgical bleeding). The NP must differentiate between platelet-type bleeding (immediate, mucocutaneous) and factor-type bleeding (delayed, deep tissue), evaluate with appropriate laboratories (platelet count, PT, aPTT, bleeding time/PFA-100), and identify inherited versus acquired causes to guide management.
Diagnosis & workup
Diagnostics & workup: - Platelet count: <150,000 = thrombocytopenia; <10,000 = risk of spontaneous bleeding; >450,000 = thrombocytosis - PT/INR: prolonged = extrinsic/common pathway disorder (vitamin K deficiency, warfarin, liver disease, Factor VII deficiency) - aPTT: prolonged = intrinsic/common pathway disorder (heparin, hemophilia A/B, vWD, Factor XII deficiency) - Bleeding time/PFA-100: prolonged = platelet dysfunction or vWD - Fibrinogen: <100 mg/dL = increased bleeding risk; <50 mg/dL = critical - D-dimer: elevated = fibrinolysis (DIC, DVT/PE) - Peripheral blood smear: schistocytes (MAHA), giant platelets (ITP, Bernard-Soulier), platelet clumping (pseudothrombocytopenia from EDTA)