Panic/Hyperventilation during wreck dive (~80 ft)

[wetb4igetinthewater]

Could go with the DST which has 2 HP ports.

Yup. I caution recreational divers to follow what technical divers do. While those interested in tech diving should ensure that what they purchase today will work for them tomorrow, the DST4 first stage is a good example of not being necessarily the best choice for a recreational diver. The DST is just fine (which I own, but in a Yoke configuration).

 

[dumpsterDiver]

Sounds to me like the op experienced a build up of CO2 from exertion that he could not get rid of possibly due to over breathing the reg or just breathing rapidly but shallow.

This is not hyperventilation, it's hypoventilation. The correct solution for this is to take a deep breath (which opens more alveoli in the lungs allowing blood to off gas more CO2) and then exhale as much as possible. Repeat until you feel like you have caught your breath (and CO2 has returned to normal levels).

A question for the reg tech experts, if the reg is hard to breath due to high cracking pressure, would a light touch on the purge help your breathing (without actually causing a big gas flow)?

I'm not an expert, but yes that will work to eliminate the work of cracking the regulator on. It also is a great technique when you are on the boat with a killer co2 headache and you are sucking on the oxygen regulator. It is oh so much more comfortable to gently press the purge than suck.

Also, your mention of a change in breathing technique is also very valuable. The diver MUST stop panting and concentrate on deeper inhlation and especially and most importantly a reasonably complete exhalation. We need to remember that the challenge is not to supply oxygen .. we have tons of that in our compressed gas supply, but the problem is to vent CO2 and this is much more efficient when we exhale all the stale air at the "bottom" of our lungs.

i wonder if new divers ever practice working really hard underwater. When I was an instructor, I would make the students do scuba sprints in the pool .. race from one end of the pool to the end and back as fast as possible and then stay underwater and recover their breath

I always felt that it was a very valuable lesson for a diver to feel how crappy it is.. to be out of breath and sucking on this damn regualtor and NOT being allow to surface. Of course it is going to be worse at 90 (or 180 feet especially), but I think this is an important lesson that should be taught to divers.

 

[gfaith]

Sounds to me like the op experienced a build up of CO2 from exertion that he could not get rid of possibly due to over breathing the reg or just breathing rapidly but shallow.

I think this is rapid shallow breathing:

Tachypnea is the medical term for rapid and shallow breathing, often confused with hyperventilation, which is breathing that is rapid but deep. Both disorders are caused by a buildup of carbon dioxide in the lungs, which causes a buildup of carbon dioxide in the bloodstream. Quoted from Study.com

 

[Bob DBF]

As for my experience, I did not want to blame the gear but a lot has lead me to believe that my octopus was also at fault.

I would agree you had two issues. First, the reg may not have been tuned properly, which may have made breathing a bit harder. Second, and more important in my mind, is over exerting yourself, and building up CO2. The second will not be fixed by a new reg, but by not over exerting yourself and proper breathing you can keep the CO2 and its side effects down.

Any modern reg that is properly tuned should work fine for you and your wife. I like Sherwood's, but each to his own.


Bob

 

[GJC]

I think this is rapid shallow breathing:

Tachypnea is the medical term for rapid and shallow breathing, often confused with hyperventilation, which is breathing that is rapid but deep. Both disorders are caused by a buildup of carbon dioxide in the lungs, which causes a buildup of carbon dioxide in the bloodstream. Quoted from Study.com

Looks like you either misread study.com or the info was wrong. Hyperventilation is not caused by high CO2 and actually results in low CO2 in the bloodstream and body tissues. Low CO2 causes the tingling of the hands and feet and cramping seen with hyperventilation. One method of treatment is breathing into a paper bag which causes CO2 to rise.

 

[Kevrumbo]

Hyperventilation is an unreasoning rapid breathing associated with psychological shortness of breath or feeling of smothering and is one of the symptom complex of a panic attack. It feeds on itself by producing a marked lowering of the pCO2 (carbon dioxide levels) with an associated drop of blood calcium levels resulting in tetany (spastic loss of muscle function). This results in a vicious cycle — pushing the diver into a peripheral narrowing and locked into panic driven behavior. Rapid breathing can also be caused by faulty equipment, causing a retention of CO2.

Abnormal carbon dioxide accumulation in the blood can occur from too high a level of metabolism (such as from exercise at depth) and/or inadequate breathing (usually not breathing deep enough or skip breathing), as well as the increased work of breathing made more difficult by the higher gas density of Air at depth.

The medical term for high carbon dioxide in the blood is hypercapnia; when the level is high enough it can cause "CO2 toxicity," which can lead to shortness of breath, headache, confusion and drowning (depending on severity).

Signs and symptoms that need to be observed are hyperventilation, shortness of breath and tachycardia (rapid heart beat), headache and excessive sweating, mental impairment and finally , unconsciousness.

(Abridged from CO2 Retention )

 

[fmerkel]

HYPERventilation (excessive breathing causing a drop in CO2 levels) vs. HYPOventilation (inadequate breathing causing a rise in CO2 leves) is frequently debated on this forum. Unfortunately some divers don't understand the terminology correctly.

IMO a fair number of cases that are discussed as a CO2 'hit', or hypoventilation are likely in fact hyperventilation. It's impossible to tell since there are no trace signs left in the diver and the symptoms to the diver are very similar. The state of mind that either condition cause while diving does not encourage cool and dispassionate reflection.

In this case I'd say it was pretty clear a case of hypoventilation caused by exercise at depth, compounded by increased gas density and possibly marginal equipment.

 

[Dizzi Lizzi]

What exactly is skip breathing? I have my guess

 

[fmerkel]

Slow breathing with very long pauses, essentially 'skipping' a breath. People talk about it a lot but I think in reality it is far less common than discussed. Most accomplished divers change their breathing rate as depth increases....we slow down with larger/deeper and slower breaths. This helps compensate for the increased density of gas as depth increases. Maybe some people call that skip breathing. I do not.
It's impossible to check the reality since you would need to get an arterial puncture and test for CO2 level and blood pH to KNOW if the CO2 was going up. That is not going to be done underwater in an unclean environment. So, we only have the divers report on it, for whatever that's worth.....

The body HATES the CO2 level to go up much. CO2 is what drives breathing. Climb one flight of stairs and carefully note your respiratory rate. It will briefly go up just a little to compensate for the increase in CO2. Walk briskly for about 5 minutes to warm up. Carefully note your pulse rate and respiratory rate + depth once you get somewhat stabilized at a sustainable level. NOW, try to halve your respiratory rate for more than 5" keeping the breath size the same. No doubling the breath SIZE, which will be your tendency to compensate!! You probably won't be able to do it. As the CO2 climbs your urge to catch up will become overwhelming. Now, imagine trying to do that for an hour, like a dive. Ugh!

If you practice you can handily get your respiratory rate down to 4 breaths/minute, even 3, and be OK. But it will not be 'normal' respiration, the breaths will be a lot larger and slower. It is still NOT hypoventilation, since your CO2 will be normal, but it's also not 'normal' ventilation. But, breathing underwater is decidedly not normal.

 

[Dizzi Lizzi]

I do that. Slow breathing with very long pauses. I don't try to do it, it just feels relaxing. It tends to be about 3 seconds in, pause 1-2 seconds, then 3 seconds out (I do concentrate on exhaling fully) then 2-3 second pause. I feel like I'm in slow motion underwater, and my resp rate drops. I've only had 1 headache after diving and that was with a lot of exertion on a shore dive. Yes breathing underwater is not at all normal, as all my friends who think I'm crazy will say.