Busy. Please wait.

show password
Forgot Password?

Don't have an account?  Sign up 

Username is available taken
show password


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.

Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
Don't know
remaining cards
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

"Know" box contains:
Time elapsed:
restart all cards
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how


HSF II Cardiovascular - Hemostasis

Hemostasis collection of events that stops bleeding by turning a portion of the fluid blood into a semi-solid clot or thrombus
Two Aspects of Hemostasis 1) anticoagulant activity 2) procoagulant activity
Anticoagulant Activity maintains blood in a fluid state while circulating within the vascular system, does not promote hemostasis, predominate and inhibit hemostasis in normal conditions
Procoagulant Activity promotes hemostasis, predominate in damaged blood vessels and hemostasis initiates, a clot forms
Virchow's Triad factors for thrombosis: 1. injuries to vascular endothelium, 2. alterations in normal blood flow, 3. alterations in the constitution of blood
Causes of Abnormal Blood Flow immobility, venous obstruction, varicose veins, atherosclerosis, atrial fibrillation
Deep Vein Thrombosis (DVT) when blood clot (thrombus) forms in one or more of the deep veins in your body, usually in the legs. because venous flow from muscle pump
Causes of Changes in Blood Constitution sepsis, chronic inflammation, hormonal changes/therapy, thrombophilia
Most important factor for maintaining normal pro- and anti-coagulant balance endothelial integrity
von Willebrand Factor (vWF) a procoagulant glycoprotein made by undamaged endothelium, binds and prevents the degradation of clotting factor VIII
Cause of Hemostasis Initiation when the balance of anticoagulants and procoagulants is shifted
Three Phases of Hemostasis 1) vascular spasm 2) platelet plug formation 3) coagulation (clotting)
Vascular Spasm (Hemostasis) smooth muscle contracts, causing vasoconstriction: a) pain, b) myogenic reflex, c) endothelins
Platelet Plug Formation (Hemostasis) injury to lining of vessel exposes collagen fibers, platelets adhere. Platelets release chemicals that make nearby platelets sticky, and platelets form the clot
Pain (vascular spasm) activates the sympathetic nervous system, increased sympathetic stimulation causes vasoconstriction
Myogenic Reflex (vascular spasm) direct response of smooth muscle to mechanical stimulation, stretch the muscle or deform it, causing mechanically gated ion channel
Endothelins (vascular spasm) cytokine proteins that constrict blood vessels. trauma to tunics increase endothelin production and shifts balance to vasoconstriction.
Platelet Phase second phase in hemostasis, subendothelial vWF exposed, platelets bind to vWF and the exposed collagen via one membrane receptor, fibrinogen binds to the other
Platelet Release Reaction aggregated platelets release 1) serotonin (5-HT) (vasoconstrictor) 2) ADP and 3) Thromboxane A2 (vasoconstrictor, eicosanoid). these all enhance platelet plug formation
Created by: connorquinby