Sweating underwater!

[mozezman]

i know it sounds odd, but my last dive was definitely a strange one for me.
i was diving in Doha, Qatar and was enjoying taking photos of the reef fish when i suddenly felt light headed.
i checked my guges, signalled my buddy that i wasn't okay and tried to remain calm. i was escorted by my buddy out of the dive site, but the feeling still haunts me and im trying to figure out what happened. the water was very warm 35 celcius/ 95 fahreheight which i thought was the cause but none of the other divers experienced this.... any thoughts.

thanks moe

 

[Doc]

Some people are aware of dehydration caused by breathing our normally dry compressed air.

You are right- water temps in the 85°F+ range can easily add to the dehydration factor. You are indeed perspiring fluid as you exert, but it remains unnoticed in the soup of salt water.

95° water? Really? Holy Cup-of-Ramen, Batman!

 

[ajduplessis]

I doubt that 95f water would cause the symptoms you describe. The water temp is lower than you core body temp. Various factors can contribute to what you described like low blood sugar levels, flu, medication, dehydration, high workload, breathing patterns, excitement, low blood pressure, age, health and fitness levels to name a few.

 

[Mr. Black]

How about CO contaminated breathing gas ?

 

[knotical]

Under normal environmental conditions, our body (even at rest) produces excess heat that needs to be dissipated. We typically perspire when the air temperature is well below 35° C / 95° F, attempting to release our extra heat energy. If we’re surrounded by water that hot, we are less able to effectively dissipate energy and could overheat. I think (but cannot find the reference) that thermal equilibrium for a human body at rest immersed in water is right around 34° C, so you could well be in the range of overheating. Unlike in a hot tub when your head is exposed to air, underwater there is nowhere else for the heat to go. So to me it sounds like it could be early signs of hyperthermia. Sensitivity naturally varies with individual.

 

[seattlepaul1975]

Wow! 35° C / 95° F......I am jealous with the 55F I dove in last week here in Seattle

 

[mozezman]

Thanks for all the replies folks. I'm kinda inclined to think that the answer is closer to knoticals description since i'm fairly healthy and fit. I will keep a closer eye out for symptoms in the future but wanted to share if someone else might find helpful. A good thought to keep in mind when diving in very warm water

 

[freewillie]

Just a few quick pointers on the human body and heat regulation. The body's normal response to an increase in core temperature is to try an lose heat. Blood vessels close to the surface of the skin will dilate increasing blood flow at the surface of the skin in an attempt to lose heat through convection and/or radiation into the environment. In hot weather (in this case water) there needs to be a difference between the surface of the skin and the ambient/surrounding temperature. The greater the difference the better and more efficiently the body will cool. In addition, the body will sweat, and the body cools by the evaporative conduction from water/sweat evaporating off the surface of the skin.

Swimmers (and in this case divers) have a rise in body temperature due to the muscle activity. As the core temperature rises the body will sweat. This goes unnoticed in a swimming pool or ocean because you are already wet. You would, therefore, lose water and can become dehydrated from the water loss through sweating. Divers are also going to lose water through your lungs in what is referred to as insensible loss as the dry air from the tanks is breathed in and out taking water vapor from the lungs with it. The end result is that you can and will be dehydrated if you dive long enough and do not replace your water loss by drinking before and after diving.

Hot tubs usually cause feelings of light headed and dizziness not due to dehydration losses but because the create a situation in the body where the internal core blood vessels tend to dilate - get larger. The increase size/diameter of the vessels leads to a temporary decrease in blood pressure and patients will experience this by feeling light headed and dizzy. I suspect given the really warm water the OP was diving in this is more likely the cause of his symptoms. As to why the other divers did not experience any symptoms is simply our individual tolerances for temperature and heat is everyone is different.

 

[luscioman]

Military divers in the gulf wear cooling vest to keep themselves from over heating.

 

[Crass3000]

I could see it happening if you were doing multiple dives without drinking during your surface intervals. Rehydration is really important.