Animals most affected
Inhalation as a consequence of:
inefficient or poorly maintained heaters based on combustible fuels, especially when used in confined spaces;
fires which break out where animals are housed;
escape of car exhaust fumes into poorly ventilated or confined spaces.
poisoning is often associated with a human case (e.g. pets in the same room as owner).
Causes anoxia in all tissues; the gas combines readily with the haemoglobin molecule in the blood to form carboxyhaemoglobin.
This process is difficult to reverse.
Toxicity is inversely proportional to the size of the animal involved; in order of decreasing sensitivity to CO:
birds > rodents > carnivores > man > cattle
Toxic doses for all animals are quoted as a % of the volume of air:
not dangerous if exposure is intermittent;
serious poisoning may result from exposure;
death within several minutes of exposure.
loss of consciousness, dizziness, vomitmg, followed by:
deep coma, or restlessness with hyperreflexia, increased muscle tone, (tremor, clonus, convulsions);
hyperpnoea, dyspnoea, severe cyanosis of the mucosae;
often rapid progression to death;
if the animal recovers from the exposure, there may be neurological or cardiac sequelae.
(Rare), symptoms often vague or nonspecific:
nausea, vomiting, diarrhoea;
reduced vision, blindness;
generalized congestion, particularly in the brain;
haemorrhages, oedema and necrosis of brain tissue, lesions of the parietal lobe;
cherry-red coloured blood.
remove the animal from the source of the gas;
ventilate the patient;
treat for shock;
Take a blood sample to determine carboxyhaemoglobin.