BO or not

[spearheads]

OK here is my story.
I'm not sure if i have blackout today or not, early on i was laying down when i got up to get a drink downstairs, i stop up and held my breath ( for no reason) and began to walk after 5 steps my vision went completely fuzzy and black, i then woke up on the floor with a very sore hip and could not remember what had just happened.

SO do you think this was a blackout or not , I'm also worried their is going to be some sort of mental barrier when i next dive which will prevent me from relaxing in the water.

[Jorg]

Yeah, if you lost time and forgot how you got on the floor then you had a blackout. And you didn't voluntarily hold your breath? It just happened automatically?

[spearheads]

Well i held my breath intentionally but not for a training reason.
I thought it could of been because i had been laying down the sudden rush of blood from standing up could of caused it.

[fogish]

The fact that you mention things get fuzzy and black and that you lost time, then it was a BO. My wife has low blood pressure and if she stands up too quickly after laying down for a long time she has trouble moving and gets very light headed with blurred vision. Now she gets up very slowly, and if she gets up too quickly she has to sit back down until it passes.

I am not sure it has to do with blood pressure, I just assume her blood rushes out of her brain with gravity and her low blood pressure has trouble fighting the initial effects of rising too quickly. I don't think holding your breath for 5 sec. would have much effect, but someone who actually knows what they are talking about could answer this better.

[spearheads]

I just found out i have a very low blood pressure and that it runs in the family, Also i have done some research on low blood pressure.

When i take a deep inhale on land i fell dizzy but when in the water this never happens, i think its got something to do with blood rushing out my brain when standing up.
So today when i held my breath and stop up this triggered a bo.
More salt for me then.



Low BP:
- Reduces oxygen consumption (extending apnea)
- Increases risk of BO from packing or deep inhales
- Increases susceptibility to dizziness from hyperventilating
- Increases risk of BO at end of apnea

High BP:
- Increases rate of O2 consumption (decreasing apnea length)
- Decreases risk of BO from packing
- Decreases susceptibility to dizziness from hyperventilating
- Decreases risk of BO at end of apnea

[naiad]

I also have low blood pressure. I am not very susceptible to packing or hyperventilation blackouts, but I would not stand up suddenly while holding my breath, as this could cause a blackout. That is one reason why I always do dry statics lying down.

Lucia

[joe123321]

I also have low blood pressure, standing up to fast, completly lose vision, get dizy and stuff, manage to stay on my feet until my vision comes back.

[spearheads]

My theories, when you dive your veins constrict and blood pressure increases, so my low blood pressure should not be a problem.
But if that's wrong and I'm on the bottom and make a sudden turn to the surface will the blood rush from my brain and cause similar problems to when in normal atmospheric pressure ,or will the difference in pressure stop this from happening.
Hope that makes sense.

[joe123321]

Originally Posted by spearheads

My theories, when you dive your veins constrict and blood pressure increases, so my low blood pressure should not be a problem.
But if that's wrong and I'm on the bottom and make a sudden turn to the surface will the blood rush from my brain and cause similar problems to when in normal atmospheric pressure ,or will the difference in pressure stop this from happening.
Hope that makes sense.

That is a good question, Id like to know. Someone get trux in here

[trux]

Yes, that's right. Unlike at seals where the diving reflex has no significant influence on blood pressure, at humans the blood pressure raises because the vasoconstriction effect is greater than that of the bradycardia (slower heart rate). At seals those two effects are about the same and compensate each other. So theoretically, freediving may be more dangerous for people with high pressure, because it may rise to dangerous levels. However, the effects may differ at individuals, so you always do better consulting a specialized physician.

[joe123321]

Originally Posted by trux

Yes, that's right. Unlike at seals where the diving reflex has no significant influence on blood pressure, at humans the blood pressure raises because the vasoconstriction effect is greater than that of the bradycardia (slower heart rate). At seals those two effects are about the same and compensate each other. So theoretically, freediving may be more dangerous for people with high pressure, because it may rise to dangerous levels. However, the effects may differ at individuals, so you always do better consulting a specialized physician.

Thanks for clearing that up, You know everything