i think he may be referring to the mammalian diving reflex, which is a
significant reduction of pulse and breathing rate when a person gets
immersed suddenly in cold water. you can try this yourself by filling
the sink with icewater, monitoring your pulse, then putting your face
in the water for 10 seconds or so. not sure i've heard of death
resulting from this, tho it could happen i suppose. more commonly,
this reflex can keep people alive for upwards of an hour underwater.
there have been cases of people recovered from icy ponds , who were
under water for extended periods of time, but had no residual bran
damage from it.

the vagus nerve is the 9th cranial nerve, that leaves the brain and
controls a whole range of activities. i'm not sure how getting water up
the nose per se would have much of an effect, but it is hard to imagine
getting water up the nose w/o getting one's face wet as well.

Rob wrote:
You're the physician - see mine earlier - what IS the "vagus" nerve? And
does the source Huthison cites have any credibility? (Keatinge, W.R -
Survival in cold water - Blackwell Scientific Publishers (1969)


"Steven" wrote in message
ups.com...
well, as i said, it could happen. and as a physician, i have seen cases
of aspiration pneumonia where people die pretty quickly. however, as a
paddler, i have had water up my nose constantly, and i have never even
come close to this. I suspect in order for this to be a reality, it
would be necessary for water to go much further than your nose. the
original claim that water up the nose can be fatal, IMHO, is wrong.