Hyperbaric Oxygen Therapy (or HBOT) in veterinary medicine is the same as human medicine that is the delivery of 100% oxygen under pressure to the "patient". In this case the patient rather than being a human is an animal. The pressure we use is generally 1.5 to 2.4 atmospheres (a pressure equal to that produced by 16 to 46 feet of seawater). The pressure is provided using a mono place stainless steel pressure chamber that looks similar to diving decompression chambers used on ships. Clients tell us that it resembles mini _submarine with two portholes and a "hatch" at one end. It is approximately 3 feet in diameter and 4 1⁄2 feet long (photo). Oxygen at high flow is infused into the chamber until the desired pressure is reached. This generally takes 10 minutes to reach the desired pressure in our animal patients. We observe them through the portholes and note any changes in their attitude that might indicate some distress (presumably due to pressure changes in the sinus or middle ear). It has been rare to have to stop the descent but on occasion we have slowed the descent down because of observed discomfort. In animals that are very excited we tranquilize with a phenothiazine – based anxiolytic such as acetylpromazine. Most animals become comfortable in the chamber only requiring a small amount (1/2 -1 mg) of the tranquilizer.
Occasionally up to 2-3 mg will be required. The treatment times begin when the desired pressure is reached and they range from 30 minutes to 2 hours depending on the patient's condition and the indication for which it is being used. Most treatment times average one hour. Decompression which takes another 10 minutes is then accomplished and the patient is removed from the chamber.