Pathophysiology Flashcards
(43 cards)
Incidence
number of new cases per unit time
Prevalence
number of cases at any one time
ischemia
lack of arterial blood flow (arterial occlusion, venous occlusion); pump failure
hypoxemia
failure of lungs to oxygenate blood flow, failure to ventilate or perfuse the lungs, inadequate RBC mass, inability of hemoglobin to carry or release oxygen
failure of oxidative phosphorylation
cyanide, carbon monoxide, dinitophenol
what happens with hypoxemia?
ETC stops, Na+/K+ATPase fails, Na+ and H20 enter cell, lactic acid accumulation and pH drop, Ca2+ATPase fails, Ca2+ enters
free radical injury
radiation, poisons, normal metabolism
damage cell membranes, DNA mutations, aging?
superoxide dismutase
turns free radicals into H2O3
catalase
hydrogen peroxide to water and oxygen
antioxidants
vitamin E and C
chemical injury
acids/alkalis destroy membranes, formaldehyde crosslinks proteins and DNA
cyanide
blocks ETC (e- adherers)
mushrooms
destroy ribosomes
chemotherapy
damages DNA
strychnine
motor neuron synapses
carbon monoxide
replaces O2 on hemoglobin, blocking ETC
cellular accumulations
triglycerides, glycogen, complex lipids or carbs, pigments, calcium
fatty change
involves heart or liver, marker for injury, closely linked to heavy drinking, NASH, malnutrition/hyperalimentation, outdated tetracycline, ill bypass
mechanisms of fatty change
too much free fat coming from liver, too much fatty acid synthesis by liver, impaired fatty acid acid oxidation by liver, excess esterification of fatty acid to triglycerides by the liver, too little apoprotein synthesis by liver, failure of lipoprotein secretion by liver
glycogen storage diseases
often pediatric problem; inborn errors of metabolism
pigments
carbon (anthracosis in lungs), lipofuscion, melanin, bilrubin
melanin
eumelanin: protects from UV light
pheomelanin: generates free radicals UV exposure (abnormal)
Hyperpigmentationincreased ACTH
hemochromatosis: decreased breakdown of melanin
bilirubin
yellow/orange, product of hemoglobin breakdown, normally conjugated by the liver and excreted in bile
jaundice
too many red blood cells being broken down(hemolytic processes) ; liver can’t conjugate bilirubin fast enough; biliary obstruction (gall stone, pancreatic cancer)