Final Flashcards
ethanol/methanol affect what species the most?
cattle, calves, lambs and pigs
This toxin may cause green or black urine
phenolic compounds
what is the MOA of phenolic compounds?
denature and precipitate cellular proteins –> direct irritation –> coagulative necrosis
what toxin can cause burns on skin and in the mouth?
phenolic compounds
what is the most significant MOA of phenolic compounds that separates it from mainly everything else?
STIMULATES respiratory center –> hyperventilation and respiratory ALKALOSIS
what toxins cause methemoglobinemia?
phenolic compounds, nitrogen oxide gases, H2S, copper, iron
what are the skin, eye and CNS signs of phenolic compounds?
skin = coagulative necrosis, ulceration, white plaques, intense pain eye = corneal ulcerations CNS = ataxia, seizures
what does urine + 20% ferric chloride detect if it produce a purple color?
phenols
what Tx is contraindicated for phenols?
emetics or gastric lavage
what is recommended for decontamination of the GIT of phenols?
milk, egg whites, followed by activated charcoal and saline cathartics
what is recommended for decontamination of the skin of phenols?
rapidly decontaminated with PEG or glycerol followed by mild dish soap, also dressings soaked in 0.5% Na bicarb but NOT OILY DRESSINGS
what are the 3 types of detergents? how do they vary in toxicity?
non-ionic = low toxicity (soap) anionic = moderate toxicity (laundry, dish washer) cationic = high tox (fabric softeners
how do you Tx anionic detergents?
water/milk, activated charcoal if large quantities and no corrosive injury, bathing, supportive care
how do you Tx cationic detergents? what is contraindicated?
water/milk/egg whites or activated charcoal to dilutee and neutralize the alkaline
contraindicated = emesis and gastric lavage
what is the characteristic smell of bleach toxicity?
dog swimming in a pool!
what do household bleaches contain as the source?
3-6% sodium hypochlorite
what is the MOA of bleach?
bleach + acid/ammonia solutions –> bleach causes release of Cl/chloramine gas and hypochlorous gas –> cause severe respiratory and eye irritation
concentrated solutions are highly CORROSIVE to mucous membranes –> hypochlorite ion is oxidizing
what do you avoid for Tx of bleach toxicity?
ACIDS
what is different about xylitol and the FDA?
is NOT required to list as active ingredient
what are the sources of xylitol?
sugar substitutes
what species are susceptible to xylitol?
DOGS
what it the MOA of xylitol?
potent promoter of insulin release in dogs –> hypoglycemia
large doses = liver failure, GI hemorrhage and DIC
what lesions are associated with xylitol?
hypoglycemia only = no specific lesions
liver failure = petechial ecchymotic or GI hemorrhage, severe hepatocyte loss or atrophy and hepatic necrosis
what Tx for xylitol is NOT effective?
activated charcoal
what do methylxanthine alkaloids include?
caffeine, theophylline, theobromine
what species are most susceptible to methylxanthines?
DOGS, cats
what toxin undergoes enterohepatic recycling?
methylxanthines
what is the MOA of methylxanthines?
phosphodiesterase inhibition (raise cAMP) and competitive inhibition of adenosine receptors –> seizures
what are the C/S of methylxanthines?
theophylline = mild acidosis, tachycardia caffine/theobromine = hyperactive, panting, tremors, hyperthermia, VPCs with bpm >200
what do you use to Tx arrhythmias from methylxanthines?
beta blockers = propranolol, metoprolol (better excreted), lidocaine for frequent VPCs
what animals are most susceptible to NH3?
swine, poultry
what is the MOA of NH3?
DIRECT IRRITATION of MM, pulmonary edema, alkalosis and compensatory acidosis
what are the C/S of NH3?
RED MM, decreased growth and egg prod in birds, pulmonary edema causes dyspnea
what has a rotten egg smell?
hydrogen sulfide
what is the most dangerous sewage gas?
H2S
what are the lesions of H2S?
dark blood that may not clot, tissues may be dark or greenish/purple, sewage odor
what is used to Tx H2S?
Na nitrate IV = forms methhemoglobin that binde H2S radical and reactivates cytochrome oxidase
what does CO smell like?
nothing!!!
why did miners use canaries for CO?
smaller animals have faster breathing rate and smaller Vd, so may show toxicity before us
what is the MOA of CO?
CO combines with hemoglobin –> forms carboxyhemoglobin (COHb) which CANT carry O2, interferes with release of O2 carried by normal hemoglobin –> increased stability of Hg-O2 bond, LEFT SHIFT OF O2 DISSOCIATION CURVE, Haldane effect!!!
what lesions are present with CO toxicity?
blood is BRIGHT RED and MMs are HEALTHY PINK, chronic cases may have brain edema, hemorrhage and necrosis that can cause deafness in dogs/cats
what is the best Tc for CO?
O2 or 5% CO2 in O2 administered with positive pressure –> HYPERBARIC O2
this toxicity is associated with silos
nitrogen oxide gas
what are the colors of the nitrogen gases?
NO2 = reddish/brown N2O4 = colorless mixture = yellow/yellow brown, chlorine odor
for nitrogen oxide gas, brief exposure to high concentrations is _________ toxic than chronic exposure to low concentrations
MORE
what is the MOA of nitrogen oxide gases?
diect irritation of MM by nitric acid –> low solubility –> pass through upper resp tract and cause lung damage –> hypoxia
How would you Tx methemoglobinemia caused by nitrogen oxide gases”
methylene blue IV
what can petroleum products do to the skin of cows?
bovine skin hyperkeratosis
what species is most susceptible to petroleum products?
CATTLE
what are the systemic effects of petroleum products?
mainly CNS depression, liver/kidney damage, bone marrow suppression with chrnic exposure, some SENSITIZE MYOCARDIUM to endogenous catecholamines –> arrhythmias/arrest
what odor does petroleum have?
oil/kerosene
what is contraindicated in petroleum toxicosis?
emetics, gastric lavage, GLUCOCORTICOIDS
what kind of fluoride toxicosis is most common?
chronic (fluorosis)
what species is chronic fluorid toxicosis seen mainly in?
herbivores, esp DAIRY CATTLE
what is the MOA of acute fluoride toxicosis?
caustic effect on GI mucosa, HYPOCALCEMIA, coagulation defects, increased capillary permeability, enzyme inhibition
what is the MOA of chronic fluoride toxicosis?
alteration and delaying mineralization of teeth and bones –> black/brown discoloration of defective enamel due to oxidation of organic material in teeth, may see osteoporosis
what is the best specimen for fluoride toxicosis?
BONE
where do bone lesions begin for fluoride toxicosis?
PROXIMOMEDIAL 1/3 OF METATARSAL
