The hyperbaric chamber at Cayman Islands Hospital in George Town is primarily there to serve the needs of scuba divers experiencing symptoms of decompression sickness. However, it is also increasingly being used to treat patients suffering from advanced diabetes, said Richard McLeod, during a talk on the “Science of the Hyperbaric Chamber”, during the STEM series of talks that took place last week at the University College of the Cayman Islands.
Hyperbaric chambers for divers
In order to understand how this works, Mr. McLeod first explained how hyperbaric chambers function.
Recreational scuba divers generally breathe air, which is comprised of about 20 per cent oxygen and 80 per cent nitrogen. At depth, the nitrogen in the air they breathe diffuses through the lungs into the bloodstream.
As nitrogen is an inert gas, this is not usually a problem. However, should divers remain at depth for too long, or ascend too quickly, this nitrogen may come out of solution in the blood, forming small bubbles. These bubbles can then migrate to almost any part of the body, causing symptoms that may vary from skin rashes and joint pain to paralysis or even death.
When a scuba diver enters the hyperbaric chamber, they are basically returned to “depth”. That is, the pressure inside the chamber is increased until it is equivalent to the pressure a diver would encounter at a depth of 60 feet, which is roughly three times atmopsheric pressure.
The patient then breathes pure oxygen for 20 minutes, followed by five minutes breathing air, at pressure. This cycle is repeated for several hours. The pressure forces the bubbles back into solution in the blood. Breathing pure oxygen at “depth” has the effect of accelerating this process by thoroughly oxygenating all the tissues. The pressure in the chamber is gradually reduced bringing divers back to the “surface”, having eliminated the nitrogen bubbles.
Hyperbaric treatment for other conditions
The effects of breathing pure oxygen at pressure is increasingly being used to treat other conditions, Mr. McLeod said.
In the Cayman Islands, where diabetes is common, some patients suffer from diabetic ulcers on the feet, which are the result of circulation not reaching the extremities. Doctors can prescribe treatment in the hyperbaric chamber in such cases.
For diabetic patients, a spell in the chamber breathing pressurised oxygen has the effect of sending oxygen to areas that are not receiving adequate blood flow. A series of treatments in a hyperbaric chamber can save a diabetic patient from amputation, Mr. McLeod said. Hyperbaric chambers can accelerate healing in a number of other situations and it has also been successful in treating individuals who have recently received skin grafts or those suffering from carbon monoxide poisoning, bone infections and burns.