One of the interesting surprises that I had on Utila was visiting the hyperbaric chamber facility. The chamber is located in the same complex as the Bay Islands College of Diving. The chamber seems very well equipped and the staff seem very knowledgeable and current on diving medicine. The chamber staff graciously spent about an hour with my friend and I explaining all the various facets of their operations.
From what I understood, the chamber is funded, at least in part, by a small fee that is levied on each dive. I believe it is called a reef fee, but I am not sure. The chamber is run as a non-profit under the direction of a local doctor.
One of the interesting tidbits that I learned while talking to the chamber techs was that they have had a number of divers who presented with symptoms of decompression sickness, that were dehydrated. It seems that in the very hot and humid climate like Utila divers have a difficult time staying properly hydrated. To me, this again underscored the importance of hydration before and after diving. Interestingly, Dr Campbell describes some factors that contribute to diver fluid loss (http://scuba-doc.com/dehyd.htm)
1. Scuba tanks have extremely dry air inside. As this air is taken into the lungs and saturated--nearly twice the normal amount of water is lost from the body.Consequently it is easy to see how one can become dehydrated during a dive.
2. Negative pressure breathing causes divers to lose about 350 cc/hour from their circulating blood volume, a phenomenon called immersion diuresis and seen also in snorkelers and swimmers.
3. Cold inhibits anti diuretic hormone, causes peripheral vasoconstriction, driving fluid back into the core and stimulating diuresis resulting in losses of plasma volume.
Personally, I like to drink at least a glass of water before each dive. It is different for everyone of course, but as divers we sometimes forget about how important hydration is.
The following excerpt from Dr Ernest S. Campbell, M.D., FACS (http://scuba-doc.com/dehyd.htm) eloquently describes the importance of proper hydradation.
The importance of entering a dive well-hydrated cannot be over-stated. Prehydration of divers should include regular ingestion of fluids several hours before, 15-20 minutes before and between dives, particularly if multiple dives are to be made each day. The urine should be "clear and copious", the urine test for divers proposed by Dr. Jeff Davis