Question Any information on increased nitrogen uptake by a panicking diver?

[RedSeaDiver2]

Just wondering if there is any information or thoughts on whether a panicking/scared diver at depth will take on more nitrogen than normal? By panicking I am thinking of things like a diver that suddenly has a close encounter with a dangerous species of shark, has a really bad leg cramp that they can't deal with alone and are are in considerable pain etc - things that result in a more rapid breathing rate and higher heart rate. Any thoughts would be appreciated.

 

[RedSeaDiver2]

I guess logically it would add to nitrogen uptake - even though there might not have been a high physical workload.

 

[rongoodman]

I can't see any reason why it would. The amount of N2 in the various tissues is determined by depth/pressure and the gas being breathed, and the diver's state of mind wouldn't have any affect on either. I suppose it's possible that increased HR and breathing might move N2 absorption along a little more quickly if equilibrium at that particular depth hasn't been reached yet.

 

[Wibble]

Panic might create more CO2, possibly through shallow breathing.

CO2 is many times more narcotic than nitrogen

Panic is the most lethal issue.

 

[rsingler]

Nitrogen uptake is not increased with hyperventilation. Period.
N2 uptake is perfusion, solubility and partial pressure dependent. If you suddenly increased perfusion to an area of the body that had been vasoconstricted (due to cold water, perhaps), you might have a small increase in uptake to that tissue. But it's not a big increase into suddenly active muscle tissue that is already well perfused.

Short answer: panic is not a factor in subsequent DCS from increased nitrogen accumulation, because it doesn't happen that way.
Surfacing quickly due to panic might well be.

 

[JonG1]

Pretty sure DAN correlated dcs with panic and also poor viz iirc bizarrely ill see if I can find the report.

 

[JonG1]

Dive Risk Factors, Gas Bubble Formation, and Decompression Illness in Recreational SCUBA Diving: Analysis of DAN Europe DSL Data Base

 

[JonG1]

It's buried in the conclusion but does suggest a predisposition in stressed divers poss due to hormonal effect

 

[rsingler]

Shear forces in muscle in vigorous exercise are correlated with bubble formation, so that makes sense.
And injury kinins may play a role.
Lots still to learn...

 

[GJC]

It's buried in the conclusion but does suggest a predisposition in stressed divers poss due to hormonal effect

This makes sense since stress can cause release of vasoconstrictors which can reduce blood flow to some tissues (reducing tissue nitrogen offloading). Same effect as getting cold during decompression.