Hemodynamics- Things From Robbins Q's Flashcards
What is edema?
Swelling of tissue due to increased fluid in interstitial tissue spaces. It can be localized or generalized.
What is fluid in the pleural cavity ?
Hydrothorax, the fluid is called pleural effusion
What is fluid in the abdominal cavity?
Ascites, which is also called peritoneal effusion.
What is generalized edema?
Anasarca
What is the most common cause of generalized edema?
Heart failure.
What is the first sign of nephrotic syndrome?
Periorbital Edema
What is it called when you can poke edema with your finger
Pitting Edema which makes up 99% of edema
What is hyperemia ?
(Erythema) An active increase in arterial blood flow.
What is congestion ?
Passive decrease in venous outflow
What is hemorrhage ?
Extravasation of blood due to a vessel rupture
What is a hematoma ?
Hemorrhage enclosed within tissue
What is Petechiae
Tiny hemorrhages due to platelet deficiency
What is hemostasis?
The maintenance of blood in a free flowing liquid state in normal blood vessels and the formation of a blood clot (Hemostatic plug) at a site of vascular injury
What are platelets?
A-nucleate cellular components of blood important in initiation and propagation of clotting
What is thrombosis?
Inappropriate formation of blood clot in a blood vessel ( Usually occlusive)
What is hypercoagulability
The abnormal tendency to form blood clots.
What is a coagulapathy?
An abnormal tendency to bleed
What is embolism ?
A detached intravascular solid, liquid, or gaseous mass carried by the blood to a site distant from its point of origin.
What are the 4 fates of a thrombus ?
- Propagation
- Embolization
- Dissolution
- Organization and Recanalization
What is propagation of a thrombus ?
The thrombus enlarges through the accretion of additional platelets and fibrin increasing the odds of vascular occlusion.
What is dissolution ?
Activation of fibrinolytic factors may lead to tis rapid shrinkage and complete disssolution. This is not likely in older thrombus because of the level of cross linking.
What is organization and recanalization ?
Older thrombi become organized by ingrowth of endothelial cells, smooth muscle cells and fibroblasts into the fibrin rich thrombus.
What places you at high risk for deep venous thrombosis ?
DVT’s are associated with stasis and hypecoaguable states. The factors for this are bed rest, right heart failure, and immobilization.
What are thrombi on heart valves ?
Vegetation. Thrombus on the walls of the heart of murals.
What is hypercoagulability?
Hypercoagulability is any alteration in of the coagulation pathways that predisposes affected persons to thrombosis and can be divided into primary and secondary disorders.
What is a lieden mutation ?
A mutation in factor V making it resistant to protein C. In this case an anti-thrombotic counter regulatory mechanism is lost.
What is an embolism ?
Intracascular solid, liquid, or gaseous mass that is carried by the blood to a site distant from its point of origin. Thromboembolism is the highest risk
What is fat embolism ?
Results from ruptured marrow or sinusoids causing fat to be released into the blood stream that will cause biochemical injury and mechanical obstruction.
**Clinical Presentation 1-3 days after event. Tachypenia anemia, thrombocytopenia.
What makes up the most common systemic embolizations ?
Intercardiac mural thrombi associated with left ventricular infarcts and aortic infarctions.
Where do venous emboli end up most of the time ?
In the lung. Arterial emboli can literally go anywhere.
When would you get amniotic fluid embolism ?
A complication of labor in the immediate postpartum period. Tears in the vaginal wall will allow squamous cells, fat, and mucin from the placenta can enter maternal
What is air embolization
When gas is precipitated in an artery or vein. They will obstruct venous flow
What does heparin do ?
Halts clot propagation- It binds to antithrombin and inactivates thrombin.
What are the inhibitors of the coagulation cascade?
- Heparin Like Molecules- enhance the inactivation of thrombin
- Thrombomodulin- Binds to
- Tissue Factor Pathway Inhibitor-
Sinosis ?
Blue do the accumulation of deoxygenated blood.
What is endocarditis ?
An infection of the heart valves, especially one that is malformed. You will haev turbulant flow which will promote clot thrombus formation
What is Heparin Induced Thrombocytopenic syndrome ?
This occurs in 5 % of patients that are treated with unfractionated heparin. This results in the development of autoantibodies that bind complexes of heparin and platelets and destroy them. The Ab’s may also bind similar complexes present on platelet activation aggregation and consumption.
Where do arterial thrombus travel ?
Toward the periphery.
What will the increase in procoagulatns and anti-fibrinolytic pathways result in ?
Microvascular thrombus (DIC) which will lead to tissue ischemia.
What does PDGF do ?
IT is stored on platelets and released upon activation. PDGF causes migration and proliferation of fibroblasts and smooth muscle cells and might contribute to the migration of macrophages.
What is a red infarct ?
A red infarct is due to a venous occlusion in loose tissue where blood can collect in the infarcted zones in tissues with ductal circulations (lung and small intestine) where inadequate perfusion by collateral arterial supply is typical. In previously congested tissues **Organs with dual blood supply,
What is a white infarct ?
Occurs with arterial occuusions in solid organs with end arterial circulations ( heart spleen and kidney ) where tissue density will limit the seepage of blood from the site of the occlusion
Organs with single blood supply Brain. Clot busting drugs will turn a white infarct into a red infarct.
What is the main histologic finding associated with infarcts ?
Ischemic coagulative necrosis with inflammatory responses
What is a line of Zhan ?
Thrombi that have grossly apparent laminations. These represent
What are all the functions of Thrombin ?
- Stimulates platelet aggravation
- Activates Monocytes and endothelial cells
- Increases neutrophil activation
- Causes Fibrin activation & Crosslinking
What does Tissue Pathway Factor Inhibitor do ?
A protein secreted by the endothelium that inactivates factor Xa and VIIa factors in the coagulation cascade.
What do Protein C and S do ?
They are vitamin K dependent proteins that act in a complex to proteolytically inactivate cofactors Va and VIIIa
**Thrombomodulin activates protein C
What molecule is responsible for fibrinolysis?
Plasmin which breaks down fibrin and interferes with its polymerization.
How is plasmin activated ?
Plasmin is activated from plasminogen by factor XII or by plasminogen activating factors.
What is the sequence of factor activation in the intrinsic pathway of coagulation ?
XII–> XII –> IX + VIII –> X + Va + Ca –> 2 –> activation of Fibrin
Ho is fibrin stabilized and what is responsible for this ?
Cross linking mediated by XIII
Is DIC a bleeding problem or a clotting problem?
A bleeding problem. You will have decreased platelet counts. Decreased Hemoglobin by hemolysis.