5 - Hemodynamic Disorders, Thromboembolic Disease and Shock (Exam 1) Flashcards
What 3 things does normal fluid homeostasis require?
- Normal intravascular pressure
- Normal intravascular osmolarity
- Vessel wall integrity
What are 4 major pathophysiologic categories of edema?
- Increased hydrostatic pressure
- Reduced plasma oncotic pressure
- Lymphatic obstruction
- Inflammation
What are 2 types of increases in hydrostatic pressure within the vascular system?
- Localized
2. Generalized
What is localized increase in hydrostatic pressure?
Obstruction or impaired venous outflow from tissue
More common in lower extremities
Pressure applied great enough to obstruct veins but not arteries
What is generalized increase in hydrostatic pressure?
Due to increased venous pressure
Congestive heart failure affects right ventricular function
What is reduced osmotic pressure of the plasma often due to?
Reduction in plasma colloid
Albumen is most important in maintaining colloid osmotic pressure
What causes lymphedema?
Lymphatic obstruction
What are 7 causes of lymphatic obstruction?
- Inflammatory Obstruction
- Damage to normal drain routes
- Neoplastic obstructive disease
- External pressure or internal neoplastic growth
- Parasitic disease
- Migration of nematode microfilaria (Filariasis)
- Elephantiasis
What is pitting edema?
Swelling that can be pushed out of interstitial space
Leaves an indentation after pressure is released
What is dependent edema?
Moves in interstitial spaces with gravitational forces
Seen in the lower portions of the body
What is anasarce?
Generalized edema
What is hyperemia?
Increased blood volume to tissue due to arteriolar dilation due to increased demand
Can also abnormally be due to inflammatory response
What is congestion?
Passive process that results from decreased outflow
May lead to cyanosis (blue tissue)
What are 3 causes of hemorrhage?
- Trauma
- Inflammatory erosion
- Neoplastic erosion
What are the 3 patterns of hemorrhage?
- External
- Internal
- Hematoma (Bruise)
What are petechiae?
1-2 mm diameter red spots due to low platelet counts
small hemorrhages
What are purpura?
> 3mm diameter red spots due to low platelet counts
Usually seen subcutaneously with bruising
small hemorrhages
What is hemostasis?
Blood-stay
Normal function, very important for survival
What is the platelet function in homeostasis?
Activated by exposure to subendothelial extracellular matrix
Adhesion to matrix followed by change in shape
Release reaction and aggregation
What are 3 disorders of platelets?
- Thrombocytopenia
- Thrombocytosis
- Thrombocytopathia
What is thrombocytopenia?
A decrease in the number of circulating platelets
What is thrombocytopathia?
Reduction in platelet function Results in hemorrhage of mucus membranes Bruising from minimal trauma Hyphema of the eye Increased menses flow Can be genetic (primary) or from drugs (secondary)
What 3 things are thrombocytopenia associated with?
- Decreased bone marrow megakaryocyte activity
- Increased pooling in the spleen
- Decreased survival of platelets
What is 1 treatment of thrombocytopenia?
Removal of the spleen
Often results in the return of normal platelet counts
What is thrombocytosis?
Excess circulating platelets
What are 5 causes of thrombocytosis?
- Idiopathic
- Bone marrow hyperplasia
- Neoplasia
- Inflammatory disease
- Trauma
What are 3 clinical manifestations of thrombocytosis?
- Thrombosis/ infarction
- Thromboemboli
- Disseminated intravascular coagulation
What are 3 primary causes of thrombosis?
- Endothelial cell injury (most common cause)
- Stasis or turbulence of blood flow
- Blood hypercoagulability
What type of thrombosis occurs on heart valves?
Vegetative infectious endocarditis
What are the most common type of thrombi? How fast do they form and where?
Venous thrombi
They tend to form slowly in lower extremities
What is propagation of a thrombus?
Accumulation of platelets that eventually causes vessel obstruction
What is embolization?
Dislodging and transportation of the emboli to other areas of the vasculature, can cause fatal damage
What is dissolution?
Thrombus removed by fibrinolysis activity
What are 3 fates of thrombi?
- Propagation
- Embolization
- Dissolution
What is an embolism?
Detached intravascular mass carried by blood away from its origin. Most are associated with a thrombus
What are 6 types of emboli that do not originate from a thrombus?
- Fat
- Tumor fragments
- Amniotic fluid
- Air
- Nitrogen
- Atherosclerotic
What is an infarction?
Ischemia that occurs downstream from vessel blockage
What is a systemic thromboembolism?
Emboli traveling in the arterial circulation, many of which originate from the heart
What is a fat embolism?
As it sounds, fat globules from tissue in the circulation
Common after broken bones, about 10% of fat emboli cases are fatal
What is an air embolism?
Usually results from injury
Also associated with decompression sickness (scuba)
Treatment includes compression chamber to force nitrogen back into the blood
What is shock?
Vascular collapse due to sudden reduction in cardiac output or large blood loss
What are the 3 types of shock?
- Cardiogenic shock
- Hypovolemic shock
- Septic shock
What is cardiogenic shock?
Shock caused by heart failure
What is hypovolemic shock?
Shock caused by loss of blood volume such as:
hemorrhage
dehydration
trauma
What is septic shock?
Shock resulting from systemic microbial infection
Endotoxin causes widespread vasodilation, sudden drop in blood pressure
