Toxic Gases Flashcards
What are the sources for Ammonia gas?
Decomposing manure
Burning nylon/plastics
fertilizer
What are the properties of Ammonia?
sharp odor
heavier than air
soluble in water
readily reacts with hydroxyl ions in moist mucous membranes to form ammonium hydroxide which is irritant and caustic
What is ammonia converted to on mucous membranes?
Ammonium hydroxide
How is ammonia absorbed?
Inhalation
What is the mechanism of action of Ammonia toxicosis?
Direct irritation of membranes Increased susceptibility to respiratory infections due to continuous irritation Decreases growth in young animals inhibits the TCA cycle pulmonary edema and lung congestion
What is the cause of death due to in Ammonia toxicosis?
asphyxia
electrolyte and cellular metabolic effects
What are the clinical signs of Ammonia toxicosis?
Red mucous membranes lacrimation coughing sneezing nasal discharge decreased growth decreased egg production dyspnea due to fluid in lungs cyanosis CNS stimulation clonic convulsions
What is the treatment for Ammonia toxicosis?
Removal of source Fresh air soothing ointments to eyes antibiotics for 2ndary infections Diuretics
What is the source of Hydrogen sulfide?
decomposition of urine and feces
coal pits, gas wells, sulphur springs
Liquid manure holding pits
Natural gas and crude oil production
What is the most dangerous sewage gas?
Hydrogen Sulfide
At what level is Hydrogen Sulfide immediately fatal?
400ppm
What levels can poultry withstand of Hydrogen Sulfide?
4000ppm
What is Hydrogen Sulfide converted to in the blood?
Alkali sulfides
Where is Hydrogen Sulfide readily absorbed?
Lungs
GI tract
What is the mechanism of action of Hydrogen Sulfide toxicosis?
Direct irritation of mucous membranes
Inhibition of cellular respiration by inhibiting cytochrome oxidate
Stimulation of chemoreceptors of the carotid body interfering with respiratory drive
What are the clinical signs of Hydrogen Sulfide toxicosis?
sudden collapse cyanosis dyspnea anoxic convulsions rapid death irritation to ocular, respiratory mucosa and lungs
What are the lesions associated with Hydrogen Sulfide toxicosis?
Dark blood that may not clot
Tissues may be dark or greenish purple
Carcass may have H2S odor
GI contents may be black or dark gray with sewage odor
What does Hydrogen Sulfide react with?
Silver
Iron
Lead
How do you treat Hydrogen Sulfide toxicosis?
Removal of source Sodium Nitrate IV Oxygen therapy ventilation supportive treatment
What are the sources of Carbon Monoxide?
Fires
Propane
Automobile exhaust
What are the properties of Carbon Monoxide?
Odorless
Colorless
What is important to remember about Carbon Monoxide?
Smaller animals have faster breathing rate and smaller Vd so may show toxicity before humans
“Canary in the coal mine”
What is the mechanism of action of Carbon Monoxide?
CO combines with hemoglobin to form carboxyhemoglobin which cannot carry O2
Carboxyhemoglobin interferes with normal release of O2 carried by normal hemoglobin
competes with oxygen for binding on myoglobin
leads to free radical formation and attraction of leuocytes
What are the clinical signs of Carbon Monoxide Poisoning?
Sudden death Hypoxia drowsiness incoordination dyspnea lethargy coma
What are moderate concentrations of carbon monoxide associated with in swine and sheep?
stillborn fetuses
What lesions are associated with Carbon Monoxide Poisoning?
Bright red blood and pink mucous membranes