In humans we’re all familiar with choking, when food becomes lodged in the trachea (airway), the universal sign of choking and the Heimlich maneuver.  In horses however, choke means something different entirely.  Choke in horses is when feed material or some object becomes lodged in the esophagus.  The airway is not blocked and there is not the immediate risk of asphyxiation however as the horse attempts to swallow, they cannot move the blockage causing pain, anxiety and for any other feed consumed to either flow out the nostrils and mouth, or worse, down the trachea, contaminating the airway.

Signs

• Excessive salivation
• Retching
• Coughing
• The most classic sign is saliva and feed material dripping from the nostrils

Causes

There are many different causes for a horse to choke including:

• Bolting the feed (eating too quickly)
• Poor dentition
• Too large feed particles
• Eating inappropriate material (shavings, wood, unsoaked beet-pulp)
• Dehydration
• Sedation (from a veterinary procedure)
• Malformation of the esophagus

Diagnosis

Diagnosis of a choke is confirmed by passing a nasogastric tube, (a long soft plastic tube that is passed up the nose and into the esophagus) and encountering an obstruction.  Chokes can also be identified using video endoscopy.

Treatment

Treatment of a choke involves sedating the horse, to calm the animal and relax the muscles in the esophagus, and attempting to dislodge the blockage with a nasogastric tube.  Water can be used to lubricate the blockage and try to push it down into the stomach.  Sedation also helps keep the horse’s head in a very low position so that any feed material, saliva or water flows out the nose and does not further contaminate the trachea.  It is important to NEVER use mineral oil when attempting to resolve a choke!  Mineral oil could be aspirated into the lungs causing a fatal pneumonia.  Anti-inflammatories can be given to help the irritated esophageal mucosa.  Occasionally chokes will resolve on their own and very rarely do they require more advanced treatment such as general anesthesia or surgery. 

Prognosis

Almost all chokes are able to be resolved with a very small percentage requiring surgery.   The post-choke complication we worry about the most (aside from reimpaction) is aspiration pneumonia.  When the horse is choked, all saliva and feed material that they are attempting to swallow could potentially move into the trachea and down into the lower airway.  This bacteria laden material can cause a severe pneumonia if not treated. This is why horses who have recovered from choke are often placed on antimicrobials to prevent an airway infection.  These horses should be monitored closely for any signs of pneumonia, including fever, lethargy, nasal discharge, cough or increased respiratory rate.