Circulatory Disturbances Flashcards
Three parts of a vein and artery
Tunica intima, tunica media, tunica externa
What is the role of the vascular endothelium in hemostasis?
- Anti-thrombotic and pro-fibrinolytic in the normal state
2. Pro-thrombotic and anti-fibrinolytic during injury
Does NO cause vasoconstriction?
NO causes vasodilation and endothelin causes vasoconstriction
Vascular endothelium role in inflammation (list them)
- regulates the traffic of inflammatory cells
- produces inflammatory cytokines
- control angiogenesis and tissue repair
Definition of hemostasis
Arrests bleeding by the physiological properties of vasoconstriction and coagulation or by surgical means.
Fluid Distribution
Total Body Water = 65% of total body weight Plasma = 5% Interstitial Fluid = 15% Intracellular Fluid = 40% Transcellular Fluid = 5%
What is interstitium and what is it composed of?
It is the medium through which all the metabolic products pass between the microcirculation and the cells. It is composed of ECM and supporting cells.
The Extracellular Matrix is composed of what molecules?
Structural molecules such as collagen, reticulin, and elastic fibers
Ground substance such as glycoproteins, glycosaminoglycans, and proteoglycans
Edema
- Abnormal accumulation of excess extracellular water in interstitial spaces or in body cavities
- Fluid is outside both the vascular fluid compartment and cellular fluid compartment
Inflammatory edema
increased vascular permeability - exudate
example: damage to pulmonary capillary endothelium leading to pneumonia, ARDS (acute respiratory distress syndrome) this is suddent, diffuse and direct increase in vascular permeabiltiy leading to a high fatality rate followed by pneumonia if the animal survives
Characteristics of exudate
- protein rich >30g/L
- specific gravity >1.025
- total nucleated cells = less than 7,000 cells per ul
Noninflammatory edema
transudate
edema of CHF/liver failure
Characteristics of transudate
-protein poor
What is the gross appearance of edema?
- Wet
- Gelatinous and heavy
- Swollen organs
- Fluid weeks from cut surfaces
- May be yellow
Histological appearance of edema
- Clear or pale eosinophilic staining
- Spaces are distended
- Blood vessels may be filled with RBCs
- Lymphatics are dilated
- Collagen bundles are separated
Pitting edema
When pressure is applied to an area of edema a depression or dent results as excessive interstitial fluid is forces to adjacent areas
Hydrothorax
Fluid in the thoracic cavity
Pericardial effusion
“mulberry heart disease” - inflammatory edema
-fibrin strands and cloudy appearance of the fluid
Transudate fluid within the peritoneal cavity also known as
Ascites or hydroperitoneum
Anasarca
Generalized edema with profuse accumulation of fluid within the subcutaneous tissue
What is bottle jaw commonly associated with?
Submandibular edema - severe GI parasitism and hypoproteinemia in sheep
What is the clinical significance of edema dependent upon?
Extent, location, and duration
-tissue may become firm and distorted due to an increase in fibrous CT after prolonged edema
Chronic pulmonary edema characteristics
- most commonly associated with cardiac failure
- alveolar walls become thickened-> may lead to fibrosis
- congestion, micro-hemorrhages ->accumulation of heart failure cells
A local increase in blood volume and flow within the vascular bed
Hyperemia and congestion
