Hemostasis/Blood Types

Thrombus

Clot formation that stays in one location, condition is called thrombosis

Embolus

A part of a thrombus that breaks off due to elevated blood pressure and travels through circulation; condition is called embolism (ex. DVT)

Vascular Spasm

Smooth muscle is damaged, so it constricts; platelets release factors contributing to spasm; acts to decrease blood flow to minimize blood loss from damage

Platelet Plug Formation

Platelets stick (like velcro) to a tear in the vessel wall; once established onto endothelium, they release chemicals to generate fibrin and generate a clot

Coagulation

Clotting; forming of a substance called prothrombinase via extrinsic (chemicals from damaged tissue) or intrinsic (substances released by platelets) pathway

Thromboxane A₂

Further constricts smooth muscle

ADP

Causes platelets to become more sticky and increase aggregation

Fibrin

Thread-like protein used to catch elements to reinforce the clot; binds thrombin into clot to halt clot production once needed

EDTA

Anticoagulant that binds Ca⁺ in donated blood, thus interrupting the conversion of prothrombin into thrombin

Heparin

Anticoagulant that inhibits the enzymes that produce thrombin

Coumadin (Warfarin)

Anticoagulant that blocks activity of Vitamin K, therefore halting the production of clotting factors (12 total)

Aspirin

Anticoagulant that inhibits platelet aggregation by blocking Thromboxane A₂ 

Plasmin

Plasminogen is converted into its active form via thrombin and t-PA (tissue plasminogen activator); this will dissolve the fibrin thread when the damage is repaired

Hemolytic Disease Newborn (HDN)

Erythroblastosis fetalis; RH^- mother carries a Rh⁺ positive baby (inherited from father); her leukocytes will produce anti-Rh antibodies when exposed to the blood of her baby; only a problem in pregnancies after the first one with Rh⁺ babies — mother’s antibodies will attack the fetus’s blood