Tracheal collapse is a condition in which the windpipe becomes weak enough that the membrane running along the top of the trachea caves in, obstructing air flow, writes veterinarian Matt Grootenboer. Small and toy breeds are more prone to the disorder, Dr. Grootenboer writes, but it can occur in any breed. The condition may be precipitated by exposure to environmental irritants or allergens, obesity and existing medical problems. Medical treatment is successful in most cases, according to Dr. Grootenboer, but some dogs may require surgical placement of a tracheal stent.
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