Patho Exam 2

What are the three factors involved in the pathogenesis of intravascular clotting (Virchow’s Triad)?

Slowing or stasis of blood flow, blood vessel wall damage, and increased coagulability of blood.

What is a thrombus?

An intravascular clot that can occur in any vessel or within the heart.

What is an embolus?

A detached clot (or other material) carried into the pulmonary or systemic circulation that plugs a vessel causing necrosis.

What is an infarct?

Tissue necrosis caused by interruption in blood flow.

Where do the majority of venous thromboses form?

In the deep veins of the legs.

What are possible outcomes of venous thromboses?

Leg swelling from partial blockage of venous return in the leg and pulmonary embolism if clot detaches and lodges in the pulmonary artery.

What are the signs and symptoms of large pulmonary emboli?

Severe dyspnea, cyanosis, shock, and sudden death.

What are the signs and symptoms of small pulmonary emboli?

Dyspnea, pleuritic chest pain, cough, and hemoptysis.

What is the main cause of an arterial thrombus?

Injury to vessel wall from arteriosclerosis, causing ulceration and roughening of arterial lining.

What is gangrene?

When thrombosis blocks a major leg artery.

What are causes of intracardiac thrombi?

Clots can form within atrial appendages due to heart failure or arrhythmia, on surfaces of heart valves due to valve injury, or in the wall of the left ventricle post-myocardial infarction.

What may result from the formation of intracardiac thrombi?

May dislodge into systemic circulation and cause infarction in organs such as the spleen, kidneys, or brain.

What causes thrombosis by increased coagulability?

Rise in coagulation factors following surgery or injury, estrogen in contraceptive pills, hereditary gene mutations, or hypercoagulability due to cancer.

What is edema?

Accumulation of fluid in tissues.

What causes edema?

Disturbance of extracellular fluid circulation between capillaries and interstitial fluid.

What are the four causes of edema?

Capillary hydrostatic pressure, capillary permeability, osmotic pressure, and open lymphatic channels.

What is shock?

A condition in which the circulatory system is not providing enough blood to all parts of the body causing organs to fail to function properly.

What are the categories of shock?

Hypovolemic shock, cardiogenic shock, septic shock, and anaphylactic shock.

What are some symptoms of shock?

Skin cool, clammy, and pale; weakness, dizziness, thirst, nausea; shallow and rapid breathing; weak and rapid pulse; low BP; cyanotic lips and fingernail beds.

What are the factors involved in hemostasis?

Integrity of small vessels, adequate number of platelets, normal coagulation factors, normal coagulation inhibitors, and adequate number of calcium ions.

What are the three phases of blood coagulation?

Phase 1: prothrombin activator generated; Phase 2: conversion of prothrombin into thrombin; Phase 3: conversion of fibrinogen into fibrin by thrombin.