Anything that decreases oxygen intake by tissues is classified as suffocation. Drowning, suffocation by an enclosed space, toxic fumes, choking from a foreign body in the throat, carbon monoxide poisoning, and chest wounds are the most common injuries. The most common signs of suffocation (oxygen deprivation) includes severe anxiety and loss of consciousness. The tongue soon turns blue. Immediate treatment is required to reestablish breathing. Bring the animal to a veterinary clinic as soon as possible.