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Risking blackout with heavy packing ?

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Fred S.

New Member
Sep 22, 2001
From experience I know that packing the lungs can be very beneficial for static performances.
But analyzing what happens in the body while doing static, I came up with a question about it.

If you pack your lungs heavily, you create a strong artificial overpressure in your chest, leaving less room for the other organs etc. This causes a lot of pressure on the heart and the artery in the chest which in their turn limit the oxygen transport to the brains.

According to some scuba-literature this is quite similar to the case when scuba-divers control their buoyancy with their lungs too much and risk a blackout...

So what do you guys think, is the risk of blacking out bigger due to internally squeezing the artery in the chest??

Fred S. :confused:
blackout from packing...

yes, it can happen..
I saw a film from the WC in Ibiza last year when just that happened
from what I could understand when a medical guy tried to explain it to me, if you pack too much and stay on the surface, the presure inside the lungs prevent the blood from going back into the heart and be pump around. so the bloodpresure drops and you might blackout...did that make sence?..


Hi Fred,
Perhaps you have read from people who have suffered a BO in surface after heavy packing. I have experience near-BO with heavy packing, the reason is the High intrathoracic pressure.
The venous return is the blood that comes from the veins to the right chambers of the heart, and this is pumped to the lungs to get oxygen and leave CO2 mainly, and then it pass to the left chambers of the heart to be pumped to the whole body (Cardiac Output).
When the intrathoracic pressure is very high it affects the venous return (less blood reach the right chambers).
The high pressure also affects the filling of left ventricle, imaging the heart been compressed inward by the pressure, if the left ventricle is not completly full, the Cardiac Output is less than usual.
Puting all together, less venous return and less filling of right ventricle can affect seriously the amount of blood sending to the body (brain included) and predispose to BO.
The immersion can counteract this effect

when doing some statics plus packing at home recently i managed to BO and fall off my chair.
it was quite an experience i have to say. my field of vision immediately shrank and i lost motor control to an extent which was surprising. so down i went. i was mildly aware of what was going on but couldnt manage any reasonable action to prevent my downfall.

yes, i´m rather new to using packing so i do experiment a bit.
this one showed me that until i get more experience i won´t pack anymore for statics. the bump on my head keeps reminding me.:blackeye

at least my girlfriend had a laugh

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