Hello Everyone,
In the Wikipedia Article about Shallow Water Blackout, the author asserts that Shallow Water Blackout is caused mainly by hyperventilation in shallow depth. He mentions something called "Deep water Blackout" which is a condition that takes into account deeper freedives in which pressure changes as one is going up are the main cause of the blackout. In some online references, though, and in my physiology class, the pressure changes are lumped into Shallow Water Blackout. I was wondering if there really is a distinction between these two forms of blackout and if anyone knows of any literature that outlines this difference.
This is what the Wikipedia article says about the two:
Deep water blackout occurs as the surface is approached following a breathe-hold dive of over ten metres and typically involves deep, free-divers practicing dynamic apnoea depth diving usually at sea. The immediate cause of deep water blackout is the rapid drop in the partial pressure of oxygen in the lungs on ascent.
Shallow water blackout only occurs where all phases of the dive have taken place in shallow water where depressurisation is not a factor and typically involves dynamic apnoea distance swimmers, usually in a swimming pool. The primary mechanism for shallow water blackout is hypocapnia brought about by hyperventilation prior to the dive.
Thank you,
Tratish
P.S. I missed a couple of points on a physiology exam about this because of not putting pressure as a common factor and I am curious to see if I missed these points rightly or wrongly
In the Wikipedia Article about Shallow Water Blackout, the author asserts that Shallow Water Blackout is caused mainly by hyperventilation in shallow depth. He mentions something called "Deep water Blackout" which is a condition that takes into account deeper freedives in which pressure changes as one is going up are the main cause of the blackout. In some online references, though, and in my physiology class, the pressure changes are lumped into Shallow Water Blackout. I was wondering if there really is a distinction between these two forms of blackout and if anyone knows of any literature that outlines this difference.
This is what the Wikipedia article says about the two:
Deep water blackout occurs as the surface is approached following a breathe-hold dive of over ten metres and typically involves deep, free-divers practicing dynamic apnoea depth diving usually at sea. The immediate cause of deep water blackout is the rapid drop in the partial pressure of oxygen in the lungs on ascent.
Shallow water blackout only occurs where all phases of the dive have taken place in shallow water where depressurisation is not a factor and typically involves dynamic apnoea distance swimmers, usually in a swimming pool. The primary mechanism for shallow water blackout is hypocapnia brought about by hyperventilation prior to the dive.
Thank you,
Tratish
P.S. I missed a couple of points on a physiology exam about this because of not putting pressure as a common factor and I am curious to see if I missed these points rightly or wrongly