Dehydration - is it really *that* bad?

[DevonDiver]

Patients who suffer trauma due to auto accidents and cancer patients receive fluids by IV too. Is good hydration preventive of auto accidents and cancer? If not is DCS different?

To replace lost body fluids.

Auto-accidents - external/internal bleeding and shock.
Cancer - I don't know why... possibly to administer medicines?

DCS - possibly shock related... but there's a dehydration connection, which is why I asked.

If you don't know, thanks, but I'm waiting for a qualified medical explanation.

 

[DocVikingo]

Hi DevonDiver,

Prior to recompression an IV line is established in order to administer isotonic saline to correct any existing dehydration, prevent dehydration from occurring during treatment and reduce hemoconcentration. The line also allows for the ready administration of medications, such as a benzodiazepine in the event the patient becomes seriously anxious or claustrophobic, and analgesics and anti-inflammatories for pain.

There of course is a distinction between hydration status prior to v after the development of DCI and during treatment.

Regards,

DocVikingo

 

[danvolker]

Just because there is no direct link between dehydration and DCS, DOES NOT MEAN it is smart to allow dehydration during diving.
There is still the health issue....Do you want diving to be a healthy activity for you, or do you want it to be bad for you ( to create an unhealthy state where your body must deal with higher concentrations of toxins, free radicals, and metabolic imbalances)?

Many of us want to be diving for life. I have been doing it since 1972, and enjoy it 2 to 3 times per week now. If it was like smoking cigarettes( inherently unhealthy/like dehydration) it would not be such a great way to enjoy yourself for MANY decades.

I believe as one poster just mentioned, that the cramping issue can be caused by a number of factors--these include dehydration, insufficient muscle and liver glycogen, insufficient adaptation of the diver's muscles for the exertions in a dive trip. All these issues can easily be corrected. You can hydrate yourself, you can train your leg and hip muscles to handle the workload of a dive trip, and to store much more glycogen than would be stored in the muscles of a sedentary person. On the dive day, you can drink a good sports drink that supplies both the optimal electrolytes and the protein and complex carbs your muscles can use to generate more wokload, for longer, prior to exhaustion and cramping. My favorite for this is H2O Overdrive, the product created by my nutrition guru friend Terry Giles.... See the Hydrate product he has at Products and also the key ingredients comparison chart at Comparison Chart .
I bring the Hydrate product with me when Sandra and I dive. Because of our cycling and adaptation levels, there is no chance of cramping on a dive trip, but our mindset is to make each dive as healthy as possible, so we don't like to become either dehydrated or to deplete glycogen stores that we would prefer to have brimming full for our bike ride the next day.

 

[Mr Carcharodon]

Dan,

Being well hydrated is a good thing for general health as you point out. I know I will get calf cramps if I run and then dive, or run and do masters swimming. Taking fluids, food and a bit of salt helps me prevent that. Also there is a measurable increase in heart rate with dehydration and that adversely impacts performance on long runs and rides. Being dehydrated has been said to take about 5 to 10 minutes off your marathon time which is a big deal if your racing. But my dives do not look much like a marathon or century so the same factors may not come into play or at least not to the same degree. That said dehydration appears to be way down the list as a risk factor for DCS. Doing that run prior to a dive is a bigger risk, so is getting cold during the dive. Being well hydrated maybe helpful to reduce the risk of DCS but not measurably so. It is better to focus on keeping track of time during the dive and doing a clean set of stops because that does have a measurable benefit.

 

[GrumpyOldGuy]

I am not an expert on DCS, so I will make no comment on that. I do know I have been significantly dehydrated after 2 back to back rec dives. I simply forgot to pack water (duh!). Anyway, on the second dive, we had a series of issues including getting caught in a current and having a good 45-60 minute surface swim back so shore.

In the end, all 3 of us felt like we had been run over by a mack truck with headaches, general body aches, etc... Doing a skin pinch test it was pretty obvious we were dehydrated and not just being tired from a long swim. No issue of DCS due to the shallow depth of the dive (<40ft, which also allowed 60 minute plus run times). It required 3-4 hours to get enough fluids into our system to feel better and overnight to fully recover.

Lessons learned:
1) Being dehydrated makes you feel like crap, similar to a hang-over.
2) Once you are dehydrated, its takes a long time to recover (short of an IV)
3) Only idiots let themselves get dehydrated (been there - done that).

 

[bleeb]

[tangent]The protocol involved man & dog teams. Each team was hydrated to their own satisfaction, then sent out on a long hike in warm weather.
When each team returned, they were asked to drink water until sated (okay, the dogs were just given access to water).
Measurements indicated that while the dogs uniformly re-hydrated to their pre-hike weight, the men replaced on average only half their water loss.

I'd guess that a similar experiment today would have different results. Awareness of hydration has I think changed a great deal (in the US at least) since the 70s.[/tangent]

Maybe; maybe not. With humans, the thirst mechanism doesn't really start to kick in until 2-3% body weight below optimum hydration. Dogs are probably different. Awareness on the part of humans would probably help, but if someone didn't know about that 2-3% figure or weren't keeping a close track of intake while rehydrating, they might still end up under, especially since 2% all at once even on an empty stomach will make the average sized person feel a bit bloated.

 

[ianr33]

Could someone explain the theoretical connection between dehydration and DCS please?

 

[DocVikingo]

Could someone explain the theoretical connection between dehydration and DCS please?

Hi Ian,

The short answer is that dehydration causes a reduction in blood volume and therefore less circulating blood is available for gas exchange.

Regards,

DocVikingo

 

[ianr33]

Thanks doc.

Is there a long answer involving surface tension and bubbles?

 

[Jax]

Thanks doc.

Is there a long answer involving surface tension and bubbles?

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