One of the true emergencies encountered in veterinary practice is the case of the dog that suffers from acute gastric distension, or bloat. Drastic complications which can be irreversible can occur unless the condition can be relieved promptly.
The condition is most common in breeds of large dogs. Great Danes, Irish setters, German shepherds, boxers, weimaraners and basset hounds seem to be most prone to the disease.
Most cases are seen in animals fed only one meal a day, usually at night. Often the animal has drunk a copious amount of water and then exercised. By far the majority of cases occur late at night or early morning.
The affected animal becomes increasingly restless. It walks aimlessly, soon throwing itself down only to get up again after a short time. It may start to groan and attempt to vomit, usually without bringing anything up.
Its breathing becomes increasingly labored as the distension of the stomach puts pressure on the diaphragm. If the condition is not relieved, the dog dies of respiratory and cardiac failure.
Gas accumulates in the stomach of the dog and is unable to be relieved by the normal pathways because the stomach has become twisted. The weight of food and water in the stomach enables the whole organ to swing like a pendulum. The restraining effect of the liver, spleen and intestines are overcome by the sheer weight and size of the organ.
As the dog runs or plays or rolls on the ground the amplitude of the movement of the stomach may be sufficient for it to twist upon itself through 90 degrees, or even 180 degrees. This effectively seals both the outlet of the stomach to the oesophagus and the outlet to the small intestine.
Gas produced by the normal digestive processes builds up and balloons the stomach wall. The twisting may also cut off the blood supply to a portion of the stomach wall as well as affecting the return blood supply to the spleen, which in turn tends to increase greatly in size, adding to the pressure within the abdomen.
Treatment of the condition is by immediate surgery. Extreme care must betaken with the anesthesia as the animal’s respiration and blood supply is depressed. Once the abdomen has been opened a grossly enlarged stomach and spleen fills the abdominal cavity and very little can be done until the pressure of gas is relieved with a large needle.
Once this is achieved the stomach and spleen can usually be repositioned so that a stomach tube can safely be passed down the oesophagus. If the amount of food in the stomach is very great it may be necessary to open the stomach and remove the contents.
The success of the operation depends on how badly the circulation to the wall of the stomach has been affected. In cases where the blood supply has been cut off for any length of time part of the wall of the stomach may be gangrenous and must be removed. This, of course, greatly reduces the chances of survival.
Dogs that have recovered from bloat are very prone to a recurrence. The amount of dry food fed should be very much reduced and the dog should be fed twice daily. Exercise immediately after feeding should be discouraged.