Path: Environmental Pathology Flashcards
How does ozone form and cause pathology?
nitrogen oxides form combustion rxn to make ozone
generates free radicals that injure respiratory and alveolar lining
How do sulfur dioxide particulates form and cause pathology?
emitted by coal and oil power plants, industrial processes
less than 10 microns move to alveoli, larger particles trapped by mucociliary defenses
macrophages and neutrophils react
What are some physical signs you can look for w CO poisoning?
cherry red lividity
may have soot in oral cavity
What are the heavy metals and how do they cause pathology?
found in earth’s crust, often necessary in trace amounts
lead, mercury, arsenic, cadmium
What is the role of lead in environmental pathology?
mostly occupational
tons of effects, ill-defined cut-offs
mostly stored in bones and teeth
interferes w heme production to cause anemia
headache, memory loss, lack of attention, low IQ, demyelination, ab pain, kidney dz
What is the role of mercury in environmental pathology?
fish and dental amalgams
cerebral palsy, deafness, blindness, CNS defects in fetuses
What is the role of arsenic in environmental pathology?
water, soil, wood, preservatives, herbicides
homicidal poisoning
GI, cardiac, CNS, skin damage
What is the role of cadmium in environmental pathology?
batteries
in soil, water, plants
damages lungs, kidneys, bones
What are the effects of tobacco?
irritates mucosa = bronchitis
recruits leukocytes (elastases) = emphysema
compounds risks of other exposures
increased atherosclerosis and MI, maternal risks
What are important numbers to remember w ethanol?
> .3 = coma and death
chronic alcoholics = .7
What are the various pathological effects of ethanol?
fatty liver due to NADH > NAD
cirrhosis - hepatocyte death and regeneration
portal HTN –> varices
nutritional def (B12, thiamine, calories)
heart, pancreas, fetus
increased cancers
acute respiratory depression
What are the pathological effects of aspirin?
respiratory alkalosis then metabolic acidosis
chronic use –> headache, dizziness, tinnitus, vomiting, diarrhea, gastric ulcers, bleeding, nephropothy
may lead to coma and death
What are the pathological cardiovascular effects of cocaine?
tachy, HTN, vascoconstriction-hemorrhagic stroke
myocardial ischemia-infarction due to constriction and hypercoagulation
arrhythmias
not dose dependent
What are the pathological CNS effects of cocaine?
hyperpyrexia and seizures
What are the pathological fetal effects of cocaine?
fetal hypoxia, abortion
placental abruption
focal neurologic impairment
What are the pathological effects associated w chronic use of cocaine?
nasal septum perfs in snorters
DCM
COPD-like effects in smokers
How does heroin work?
acts on mu opioid receptors
stops GABA, stops reuptake of dopamine, stimulates reward centers
What are the pathological effects associated w heroin?
sudden death - depressed respirations, arrhythmia, pulmonary edema
pulm dz - edema, foreign body granulomata, septic emboli, lung abscesses
infections inc skin
renal injury - amyloidosis and focal glomerulosclerosis
What does clinical severity of burns depend upon?
depth - partial means basal layer okay and can regenerate, full means opposite
% BSA
inhalation of hot or toxic fumes - damages airways and lungs, poisons
What are the different manifestations of hyperthermia?
heat cramps - loss of electrolytes via sweat w cramping muscles, can maintain core body temp
heat exhaustion - sudden collapse due to hypovolumia due to water loss, quick restoration
heat stroke - ambient high temps, sweating ceases, core body temp rises, peripheral pooling w myonecrosis, arrhythmia, DIC
malignant hyperthermia
What are the features of hypothermia as environmental pathology?
homeless alcoholics
intra and extracellular water freezes - increases ion concentrations, blood viscosity, vascular permeability, edema
only evident after rewarming
What is important to know about rewarming?
no one dead until warm and dead, especially children
functions halted w hypothermia can be regained after warming w/o permanent damage
some trauma pts treated w induced hypothermia
What are the types of electrical injury?
burns, v fib or cardiac/respiratory electrical impulse disruption
extent depends on amps and path w/i body
How does low voltage electricity cause injury?
120-220 V low resistance (wet skin) can cause v fib prolonged current flow causes burns at contact and to internal organs muscle tetany prolongs contact-apshyxia
How does high voltage electricity cause injury?
higher current stuns respiratory centers and causes burns
usually blown away from source –> short contact
What are the factors that can affect the pathological effects of ionizing radiation?
rate of delivery - time to repair b/w doses
field size - keep small, use shields
proliferation rate of target - faster turnover, more sensitive
hypoxia - center of tumors w no blood flow, no damage
vascular damage - sensitive endothelium leads to leakage
CNS effects due to vascular damage not direct damage to neurons
What is total body radiation?
from atomic bomb, nuclear power plant accident, etc
even low doses devastating
What are the clinical manifestations of total body radiation?
acute radiation syndrome = N/V, fatigue
1-5 Gy = hematopoietic form
5-50 Gy = GI form - toxemia, death in 8-9 days
over 50 Gy = cerebral form - death w/i hrs, max 3 days
