Chapter 3 Flashcards
too little hemodynamic homeostasis causes:
bleeding and shock
too much hemodynamic homeostasis cause:
clots (thrombus)
2 examples of increased blood volume
hyperemia and congestion
hyperemia
active process which dilates the arterioles
causes redness (erythema)
can occur during exercise or inflammation
congestion
passive process which obstructs veins causes blueness (cyanosis) DVT or CHF
Examples of congestion
acute respiratory distress syndrome
chronic pulmonary congestion
congestive hepatopathy
examples of congestive hepatopathy
chronic passive liver congestion
cetrilobular hepatic necrosis
hemosiderin-laden macrophages
Edema
abnormal accumulation of interstitial fluid
examples of localized edema
lower extremities, hydrothorax, ascites
hydrothorax is localized edema of _____?
the pleural cavity
ascites is localized edema of _____?
the peritoneal cavity
fluid balance is maintained by what 2 factors?
hydrostatic pressure and osmotic pressure
increased hydrostatic pressure is the result of…
impaired venous flow
localized impairment of venous flow can be caused by
deep vein thrombosis
generalized impairment of venous flow can be caused by
congestive heart failure
reduced osmotic pressure can be the result of…
too few plasma proteins (albumin) caused by reduced production or increased loss
fluid imbalance can be caused by the following 5 factors
too much hydrostatic pressure too little osmotic pressure lymphatic obstruction retention of sodium or water inflammation
lymphatic obstruction is the result of…
inflammation/ fibrosis or tumors
sodium & water retention is the result of…
increased blood volume
2 causes of increased blood volume
acute renal failure and high salt diet
dependent edema is dependent on what factor?
gravity
mobile patients develop dependent edema in what area of the body?
feet and ankles
immobile patients develop dependent edema in what area of the body?
sacrum & lumbar
pitting edema is due to the accumulation of _______
transudate
non-pitting edema is due to the accumulation of ________
exudate
hemorrhage is defined as…
extravasation of blood from vessels
severity of hemorrhage is based on what 2 factors?
total blood volume lost and rate at which blood is lost
4 types of hemorrhage
hematoma
petechiae
purpura
ecchymosis/contusion
petechiae are usually ___mm
1-2mm
purpura are usually ___mm
3-5mm
3 common causes for thrombosis (Virchow’s triad)
endothelial injury
abnormal blood flow
hypercoagulability
common causes for endothelial injury
atherosclerotic plaques, hypertension, high cholesterol, vasculitis, sepsis
common causes for abnormal blood flow
turbulence (aneurysm, varicosity)
stasis (arrhythmia, immobility, valve stenosis)
4 options for the fate of a thrombus
dissolve
enlarge
embolize
organization
dissolution of a thrombus
caused by plasminogen activator
exogenous form (t-PA) can be given to break up clots
enlargement or propogation of a thrombus
will always propogate towards the heart
which way will an arterial thrombus grow?
against the flow of blood
which way will a venous thrombus grow?
with the flow of blood
what is embolization?
detached intravascular mass (moving thrombus)
where will venous emboli usually end up?
usually lodge in the lungs causing pulmonary embolism
where will arterial emboli end up?
can lodge in kidney, CNS, or extremities
what will a renal arterial embolism cause?
renal infarction —> ischemia and coagulative necrosis
what will a CNS arterial embolism cause?
Cerebral Vascular Accident (CVA or stroke)
—> ischemia and liquifactive necrosis
what will an arterial embolism in an extremity cause?
ischemia and coagulative gangrenous necrosis
recanalization
occurs during organizaton of a thrombus
eventual formation of new circulatory canals to keep blood flow
features of venous thrombus
low pressure and slow moving blood
congestion, tenderness, pitting edema
features of an arterial thrombus
infarction –> tissue death
Causes of DIC
crush injury, sepsis, obstetric complications
DIC causes _____
widespread thrombosis
DIC results in: (2)
ischemia/infarction (rapidly fatal)
Hemorrhage (from exhausted clotting factors)
3 types of embolism
solid
liquid
gas
types of solid emboli
fat, plaque debris, or tumor fragments
how are fat emboli formed?
broken long bones expose yellow (fatty) bone marrow stored in marrow cavity
Most common liquid embolism?
amniotic fluid which can cause DIC
Examples of Gas emboli?
air (injections)
nitrogen (scuba diving rapid ascent)
called Bends or Caisson’s Disease
80% of pulmonary emboli are ___
clinically silent
lungs have collateral blood supply so little to no tissue death
Saddle embolism
occurs at the pulmonary artery bifurcation
can cause rupture of the right ventricles since it is pumping against a road block
95% of PE are from
deep vein thrombosis
systemic thromboembolism
clot in the peripheral arterial system
80% of systemic thromboembolism are from
cardiac thrombi
2/3 of systemic thromboembolism are from
the left ventricle
Paradoxical embolism are weird because they ____
cross from venous to arterial system
paradoxical emboli begin as
deep vein thrombosis
Paradoxical emboli are able to cross due to
atrial septal defects or ventricular septal defects
infarction is defined as…
death of a tissue, due to obstruction of blood supply
red infarction
hemorrhagic (tissue has a collateral blood supply)
white infarction
pale/anemic (tissue has no collateral blood supply)
shock
inadequate blood supply (perfusion) to tissues, resulting in cellular injury, dysfunction, & possibly death
traditional shock are types with _______
peripheral vasoconstriction
examples of traditional shock
cardiogenic
hypovolemic
traditional shock symptoms
increased respiration, HR, cold clammy hands, decrease consciousness
treatments for traditional shock
defibrillation, CPR, limit blood loss, elevate legs, IV fluids
Distributive shock are types with ______
peripheral vasodilation
examples of distributive shock
septic
neurogenic (spinal cord injury)
anaphylactic
treatment for distributive shock
vasoconstrictive meds (EpiPen)
3 stages of shock
non-progressive (SNS compensation)
progressive (hypoperfusion, glycolysis, acidosis)
irreversible (widespread membrane damage, organ failure)
shock index
HR / systolic BP = shock index
normal shock index
0.5 - 0.8
Red infarctions are usually found:
Lungs and small intestine
White Infarctions are usually found:
Heart, spleen, kidney