Bleeding Disorders Flashcards
Some bleeding disorders are caused by platelets would be…
Thrombocytopenia and platelet dysfunction
Some bleeding disorders caused by cloting wolud be….
Vitamine K deficiency, hemophilia, von Willebrand syndrome, liver disease
Some bleeding disorders caused by blood vessel integrity would be…
Vitamin C deficiency - makes collagen not work and then arterial walls get weaker. Cushing Syndrome - cortisol causes decreased vessel wall integrity
What signs and symptoms would exist with someone with a bleeding disorder?
Bleeding gums, nosebleeds, petechiae, purpura, echymoses, easy bruising, prolonged bleeding following trauma, surgery, and dental work. Blood in stools and urine, bleeding into a joint (hemarthrosis), excessive menstrual bleeding (menorrhagia)
What’s another word for platelets?
Thrombocytes. They hang out in the spleen and also removed by the spleen after 8 to 12 days.
Where do thrombocytes come from?
They develop from megakaryocytes in the bone marrow. They break apart into fragments which become platelets. One megakaryocyte makes 1000’s of platelets.
What hormone stimulates thrombopoiesis?
Thrombopoietin - which is in the liver, kidney, smooth muscle and bone marrow.
Does thrombocytopenia affect clotting?
No, it just affects how the platelet plug is formed because there’s just not enough platelets.
Does thrombocytopenia affect big vessels much?
No, it affects smaller blood vessels like the skin or mucous membranes of the mouth, nose, gi tract, and uterus.
What is the etiology of thrombocytopenia?
1) Decreased platelet production
2) Increased platelet destruction
3) Increased sequestration by the spleen
What would cause decreased platelet production?
1) Folate and vitamine b12 deficiency
2) aplastic anemia (idiopathic or chemo)
3) Radiation therapy or chemo
4) Leukemia (crowding of bone marrow by malignant cells)
5) Infections (HIV, cytomegalovirus)
What would cause increased platelet destruction?
1) Drug induced thrombocytopenia (heparin)
2) Immune Thrombocytopenia purpura (ITP) (antibodies target platelets)
3) Autoimmune disorders (Lupus)
4) Mechanical injury (heart valves, malignant hypertension)
What would cause splenic sequestration (pooling) of platelets?
1) Splenomegaly (from portal htn, or liver or heart failure) The spleen becomes overactive and destroys platelets and WBC’s
2) Hypothermia
Does whole blood have platelets?
No
In Heparin induced thrombocytopenia, what do antibodies bind onto?
They bind onto heparin-platelet factor 4 (PF-4) complexes. PF-4 is released from platelets and bind to heparin and then 10% people develop antibodies against this complex.