Cyanide poisoning Flashcards
What plants contain cyanogenic glycosides?
Sudan grass
Johnson grass
Sorghums
Wild cherry
What is sodium nitropusside used for?
as a hypotensive
What does combustion plastic compounds produce?
HCN gas - hydrogen cyanide gas
T/F. HCN accumulates more as the plant dries
False, it disappears as the plant dries and also from the rumen contents
T/F. cyanide is irritant to mucous membranes, and the CN radical forms complexes with a number of chemicals such as ferric ion, cupric, and molybdenum
True
T/F. Cyanide has antithyroid effects
False - Thiocyanate SCN has antithyroid effect but not cyanide
What animals are more susceptible to cyanide?
Ruminants are more susceptible than horses and swine
T/F. Sheep are more susceptible to cyanide than ruminants?
false, less susceptible
What does the hydrolysis of cyanogenic plants by the rumen microflora cause?
the release of cyanide
What does plant damage (stunting, wilting, trampling, frost, drought, or treatment with 2,4-D) cause?
The release of B-glucoside that causes hydrolysis of cyanogenic glycosides and release of cyanide (HCN)
What part of the plant contains more cyanogenic glycoside?
The seeds > leaves > bark > stems > fruit
T/F adult plants contain more glycoside than young plants
False - young and growing plants contain more glycoside
What soil conditions might increase glycoside in plants?
nitrogen or low phosphorus
How is HCN absorbed?
form GI tract, inhalation or skin
T/F. CN in the presence of thiosulfate is metabolized by serum and liver sulfurtransferase (rhodanes) to thiocyanate (SCN) which is relatively more toxic and excreted in urine
False - less toxic
Excess CN in the blood and tissues binds with ferric iron and cupric copper of the mitochondrial cytochrome oxidase, which causes what?
Blocks electron transport and inhibits the cells to utilize the available oxygen resulting in histotoxic anoxia
What acid base disorder occurs with cyanide poisoning?
Metabolic acidosis due to anaerobic glycolysis
T/F Cyanide has a prominent vasodilator effect
False - vasoconstrictor
Cyanide may inhibit enzymes of ______ and _____ and decrease cellular energy
Glycolysis and citric acid cycle
What clinical signs will you see with cyanide poisoning?
Tachypnea, anxiety, severe panting, gasping, may die without showing clinical signs
T/F. Cyanide poisoning may have goitrogenic effects
true
What lesions will you see on an animal with cyanide toxicity?
Mucous membranes are bright red, blood cherry red and may not clot
GI and lungs show congestion and petechial hemorrhages
What are good specimens to test for cyanide poisoning?
Brain and heart
T/F. All specimens, including blood, should be frozen immediately and kept frozen until analysis
False - except blood
What are good indicators for the presence and severity of cyanide poisoning?
Lactic acidosis and increased anion gap
How would you treat cyanide poisoning?
Sodium nitrite 20% IV
