crazy headache and nitrox?

[Rred]

Incidentally-
If anyone thinks "Oh, I can use one of those $25 fingertip blood oxymeters they sell online to measure the oxygen saturation of my blood" that won't work. The oxymeter doesn't know if your hemoglobin is dancing with oxygen or carbon monoxide, it all registers pretty much the same. So, no easy well to check this in the field, short of "Does this guy look blue to you?" and by then things are kinda extreme.

 

[GJC]

Incidentally-
If anyone thinks "Oh, I can use one of those $25 fingertip blood oxymeters they sell online to measure the oxygen saturation of my blood" that won't work. The oxymeter doesn't know if your hemoglobin is dancing with oxygen or carbon monoxide, it all registers pretty much the same. So, no easy well to check this in the field, short of "Does this guy look blue to you?" and by then things are kinda extreme.

People don't get the blue skin coloring with CO poisoning. In some extreme cases skin appears very red. CO binding with hemaglobin causes the red coloring and prevents the blue coloring normally seen in O2 desaturated blood.

 

[Dr Simon Mitchell]

I am also aware that in an ideal world you would do a double blind study.

Hello Gareth,

Dry dives with exercise, but no difference.

Simon M

 

[Dr Simon Mitchell]

Hello,

Elevated CO2 levels are almost certainly the most common cause of headache during and after diving. In the context of this thread, the question then becomes, is there any way that breathing an elevated PO2 could result in higher levels of CO2? The answer is "possibly".

As someone esle has pointed out, it is not that breathing more oxygen causes production of more CO2 per se but rather that breathing a higher PO2 can depress the response of our breathing control system to rising levels of CO2 so that we don't breathe enough to keep the CO2 at normal levels. In other words, we retain CO2. At inspired PO2s relevant to nitrox diving the effect seems relatively subtle, but some people are almost certainly more vulnerable to this than others, and so CO2 retention enhanced by nitrox (in addition to all the other diving-related factors that tend to cause us to retain CO2) is certainly a possible answer to the OP's question.

The evidence for CO2 retention during breathing of higher PO2s is discussed on page 172 of the uploaded pdf (see below), which itself is a very comprehensive review of diving-related respiratory physiology and those other factors that cause CO2 retention.

Simon M

 

[MaxBottomtime]

Hello Gareth,

Dry dives with exercise, but no difference.

Simon M

And a later study involving multiple wet dives to 18 meters.
http://scholarworks.sjsu.edu/cgi/viewcontent.cgi?article=4472&context=etd_theses
"Divers did tend to be more fatigued after diving; however, breathing gas mixture exhibited no statistically significant effect."

 

[Gareth J]

Hello Gareth,

Dry dives with exercise, but no difference.

Simon M

Thanks Simon.

 

[KentB]

As your headache seemed to come and go pretty quickly, could it have been a reverse sinus block?

I had zero issues equalizing on any dive. I havent even got around to checking for CO
Im really leaning toward I was just stressed and not really "into it"
i will check tomorrow and i have plans for 2 dives sat and 2 dives sunday, Ive managed to fill a couple tanks which i drained down to a couple hundred PSI and refilled with just air so ill check in tomorrow or monday with CO results and weekend dive results on air. if i get around to checking for CO before tomorrow il bring the tank with 32% in it and report back as well.
Im far less stressed this week than I was on the weekend in question!!!!

 

[KentB]

didn't get around to checking the tank for CO one of my guys had my CO detector on his truck.
I did 3 dives this weekend all on air in tanks I filled
dive 1 sat 48' max depth 56 min
dive 2 sat 73 min SI 93 feet max depth 70 min
dive 3 sun 22 hr SI 108 feet max depth 61 min
absolutely fine no issues at all.

 

[DandyDon]

I start carrying my Sensorcon CO detector & test the CO level in the tank before use.

FYI: I think we overlooked flow rate pressure affecting the Sensorcon readings. If you drop the unit into a gallon ziplock, then fill the bag from the tank, you should get a good reading. However directing tank gas into the unit seems to give false positive readings. Still a good, economical choice, but not under any pressure.

 

[BoltSnap]

FYI: I think we overlooked flow rate pressure affecting the Sensorcon readings. If you drop the unit into a gallon ziplock, then fill the bag from the tank, you should get a good reading. However directing tank gas into the unit seems to give false positive readings. Still a good, economical choice, but not under any pressure.

Are there adapters for the Sensorcon unit to use directly with the Tank instead of ziplock bag?