Occupational and Environmental poisons Flashcards
What size of particles get deposited in nasopharynx?
5-30 microns - these can’t make sharp turns
What size of particles get deposited in trachea/bronchi?
1-5 microns, sedimentation
What size particles get deposited in alveoli?
under 1 micron, diffusion
What are the three determinents of depositon of particles?
size, air velocity, directional chance
How are toxins removed?
blow nose, cough, ciliary movement, phagocytosis, absorption
What are the differences between gases, vapors, and aerosols?
gases - toxic agents in gaseous state at room temp and pressure. Vapors- vaporize under room temp, aerosols include solid particles and liquid droplets.
Carbon monoxide poisoning symptoms?
headache, dizziness, N/V, visual disturbances, Cheyne-stokes respiration, cherry red blood and skin.
What is mechanism of CO poisoning
prevents Oxygen binding and lowers ability of oxygen to dissociate from hemogblobin
Treatment for CO poisoning
remove from exposure, rest, Oxygen
What are lab findings for CO poisoning
Low chloride, low bicarb, low pH, low pCo2, normal pO2.
What is the mechanism for cyanide poisoning?
complexes with Fe3+ in cytochromic oxidases. Activates chemoreceptors leading to increased RR. Death is due to resp. arrest and pulmonary edema
What is the TX for CN poisoning
O2, lavage with charcoal if PO,
amyl nitrate + sodium nitrate IV – produce methemoglobinemia to bind to CN, only soon after exposure. If too long, give bicarb to temper acidosis.
Sodium thiosulfate produces thiocynate, which is excreted in urine.
What are the symptoms and labs of CN poisoning?
cyanosis, vomiting, high BP, RR increased, lactic acidosis, elevated keto acids: beta hydroxybutyrate and acetoacetic acid, lactic acid. Increased anion gap. Low pCO2, high PO2, high glucose.
Gasoline, kerosene, naphtha (lighter fluid) cause what symptoms?
CNS depression, sensitizes myocardium to epi causing arrhythmias. Increased RR, bloody sputum, diffuse pulmonary infiltrates. Organic chemicals cause reduces surfactant production and increased permeability of capillary beds.
Formaldehyde poisoning has what presentation?
Highly reactive with most cellular components thus causes coagulative necrosis, metabolic acidosis, CNS depression.
Labs with formaldehyde poisoning?
very low pH, low Cl-, very low sodium, very high LDH and AST indicating organ damage
What is lethal dose of formaldehyde?
30 mL
Treatment of formaldehyde poisoning
control of acidosis with bicarb, maintain BP with dopamine, lactated Ringers solution and 5% dextrose in water
Methanol toxicity SE
formic acid acidosis, retinal damage, CNS depression, “whiteness” to vision, increased RR
Labs for methanol toxicity
low bicarb, increased osmolality, low pH, low pCO2, high PO2
How do you tx methanol poisoning
ethanol, fomepizole, dialysis
When do you hemodialysis for ethanol?
blood alcohol > 450
What are the symptoms when you get TRASHED with ethanol?
Temp decrease, Respiration increase, Acidosis, Sedation, Hypovolemia, Electrolyte disturbance, Dialysis
How does ethylene glycol cause damage?
metabolized to oxalate which precipitates in kidneys causing tubular damage. Treat with ethanol or fomepizole.
What are SE of benzene poisoning?
CNS depression, blood dyscrasias
What do you give milk when kids consume liquid bleach?
hope HCl saponifies milk instead of tissue
What are effects of liquid bleach consumption
severe irritation of mucus membranes, eyes; pain and vomiting, decreased BP, coma
What are effects of volatile bleach (gas) exposure
Lacrimation, mucous membrane irritaiton, edema, resp. issues
Treatment for volatile bleach exposure
oxygen, morphine to reduce pulmonary pressure, furosemide IV to treat pulmonary edema
What are effects of Borax poisoning
erythematous rash, CNS depression, CV collapse, delayed hepatic/renal failure
