click below
click below
Normal Size Small Size show me how
Hemodynamic Disorder
USCSOM: Pathology: Hemodynamic Disorders
Question | Answer |
---|---|
What is transudate? | protein-poor edema that enters interstitial tissue |
What are the 5 etiologies of edema? | increased hydrostatic pressure; reduced plasma oncotic pressure; lymphatic obstruction; sodium retention; inflammation |
What is the most likely cause of generalized increase in hydrostatic pressure? | Congestive Heart Failure |
What is the likely cause of reduced plasma oncotic pressure? | loss or reduced synthesis of albumin |
What is a likely cause of sodium and water retention? | renal failure |
What is hydrothorax? | fliud in pleural space |
What is ascites? | fliud in peritoneal space |
What is anasarca? | severe generalized edema |
What are the clinically important sites of edema? | lung and brain |
What are the clinical manefestations of pulmonary edema? | dyspnea, cough, tachycardia, crackles, neck veins |
What are the localized causes of brain edema? | abscess, neoplasm, trauma |
What are the generalized causes of brain edema? | encephalitis, hypertensive crisis, trauma, obstruction of venous outflow |
What is hyperemia? | arteriolar dilation resulting in increased flow of blood to tissue |
What results in chronic passive congestion? | cellular degeneration or death; capillary rupture, small foci; hemosiderin laden macrophages |
What is nutmeg liver? | hepatocellular death and hemorrhage with hemosiderin laden macrophages |
What are the three classifications of hemorrhage from smallest to largest? | petachiae, purpura, ecchymosis |
What is hemostasis? | the balance of clotting and fluid state of blood |
What are the three main general components to hemostasis? | vascular wall, platelets, coagulation cascade |
What is the first reaction to vascular injury? | vasoconstriction |
What are antithrombotic mechanisms of endothelium? | barrier to subendothelium, prostacycling (PGI2) and NO, ADPase, heparin, thrombomodulin, tPA |
What are prothrombotic mechanisms of the endothelium? | vonWillebrand factor, makes tissue factor, tPA inhibitor |
What two things do von Willebrand factor link? | subendothelium to glycoprotein Ib receptors |
What factors are secreted after platelet adherence? | Calcium, ADP and thromboxane, Platelet factor 4 |
What does platelet factor 4 do? | binds heparin inactivating it |
What links platelets via GPIIb-IIIa? | fibrinogen |
What are the two main fxns of tissue factor? | activate X and Xa, XI and XIa |
What cements the platelets together into a clot? | fibrin |
What converts fibrinogen to fibrin? | thrombin |
What coagulation factors are clinically significant? | V,VII,VIII,IX,X,XI, prothrombin, fibrinogen |
What is prothrombin time? | aka PT; extrinsic clotting cascade |
What coagulation factors are involved in extrinsic clotting cascade? | VII, X, V, II, fibrinogen; all require vit K |
What is partial thromboplastin time? | PTT; intrinsic clotting cascade |
What factors are involved in the intrinsic clotting cascade? | all except VII, XIII |
What is Hageman factor? | Factor XII in clotting cascade |
What initiates the external clotting cascade? | Tissue factor (thromboplastin) |
What are the main anticoagulants? | antithrombin, protein c, protein s, plasmin |
What is the action of antithrombin? | inactivates IXa, Xa, XIa, XIIa |
What is the action of Protein C and Protein S? | inactivate Va and VIIIa |
What is the action of plasmin? | breaks down fibrin |
What substances can activate plasminogen? | urokinase, tPA, streptokinase |
What substances restric plasmin activity:? | alpha-2 antiplasmin (free plasmin); plasmin activator inhibitor (PAI) inhibits tPA |
What is DIC? | disseminated Intravascular Coagulation |
How is DIC measured? | D-DIMER; plasmin-cleaved insoluble cross-linked fibrin |
What is Virchow's Triad? | factors favoring thrombosis; endothelial cell dmg, hypercoagulability, stasis |
What is the most common genetic hypercoagulable state? | factor V Leiden |
What is Factor V Leiden? | glut substitute for Arg; makes V resistant to degradation by protein C |
What is coumarin Necrosis? | a hypercoagulable state induced by giving coumarin to patients with low protein C |
What is Heparin-induced Thrombocytopenia? | giving heparin induces release of IV resulting in a prothrombotic state |
Antiphospholipid antibody syndrome? | serum Ab against anionic phospholipids; hypercoagulable state; recurrent thrombi, miscarriages |
What is Bernard-Soulier Disease? | defect of platelet adhesion; Glycoprotein Ib |
What is Glanzmann's Thrombasthenia? | defect of platelet aggregation; glycoprotein IIb/IIIa |
What is thrombotic thrombocytopenic Purpura | Abs for von Willebrand factor cleaving protease |
What is Hemophilia A? | factor VIII deficiency |
What is Hemophilia B? | Factor IX deficiency |
What is the most common bleeding disorder? | von Willebrand's disease |
What are lines of Zahn:? | alternating bands of mostly fibrin and mostly RBC |
What are characteristics of arterial thrombi? | usually occlusive; grey-white and friable |
What are some risk factors for venous thrombosis? | CHF, trauma, Sx, Pregnancy, cancer |
What is an embolism? | detached intravascular solid,liq,gas; originate from a dislodged thrombus |
What is a mural thrombi? | arterial thrombosis in cardiac chambers from MI, plaque, anuerysmal dilation |
What is a paradoxical embolism? | emobolous originating in veins passes to systemic circulation |
What causes fat embolism? | sever skeletal injury; burns, long bone fractures, soft tissue trauma |
What are the bends and the chokes? | decompression sickness; gas bubbles in tissue and gas emboli in lungs |
What is amniotic fluid embolism? | fetal amniotic fluid in maternal circulation; high mortality rate |
Describe a Red Infarct. | venous occlusions; dual circulation tissue; tissues with previously sluggish flow |
Describe a white infarct. | arterial occlusions in solid organs; limitation of blood flow; ischemic necrosis |
What is the dominant histologic characteristic of post-infarction healing pattern? | ischemic coagulative necrosis |
What is a septic infarct? | origin of embolus is infected tissue; usually from growth on heart valves |
What are the five classifications of shock? | cardiogenic, hypovolemic, septic, neurogenic, anaphylactic |
What are the five unifying features of shock? | high intracellular Ca, intracellular H+, cellular and interstial edema, catabolic metabolism, inflammation |
What are the stages of shock? | nonprogressive stage, progressive stage, irreversible stage |
What happens in the nonprogressive stage of shock? | maintain BP and CO; reflexes are making up for deficit |
Describ ethe progessive stage of shock. | widespread tissue hypoxia, lactic acidosis, decreased urinary output |
Describe the irreversible stage of shock. | lysosomal enzyme leakage, decreased contractility, renal failure |
What is cardiogenic shock? | decreased CO with adequate volume; loss of 40% myocardium |
How do you approach cardiogenic shock? | give fluids, ionotrope, manage infarct |
Describe hemorrhagic shock. | extreme hypotension due to loss of volume |
What are rosen's empiric criteria for dx of shock? | ill appearance; HR>100; RR>22; base deficit <-5; urine output <.5 mL/kg/hr; hypotension>20min |
What are some treatments for hemmorhagic shock? | colloids, controlled fluid resuscitation |
What are the clincal manifestation of SIRS? | elevated temp, elevated HR, elevated RR, elevated WBC |
What is the clincical signs of neurogenic shock? | hypotension and bradycardia |