john56

Sorry, it's been at least 10 years since I last used the doppler, so I don't remember the brand. I know we listened at the subclavian vein; the sound was like a river, or like wind. The unit came with 3 tips, if I remember, (one was for fetal use?) but we only used the one recommended when I took the course. We used the gel to aid in conductivity.

The big problem for us seemed to be that we would hear the occasional pop when doing our baseline recordings, before we had gotten in the water. I think the worst post-dive incidence we ever got was on the order of 10 pops per minute, and there was disagreement on whether we were actually hearing bubbles or not. I never got the opportunity to use the unit on a diver who had badly violated his or her decompression, so other than a recording in the course I never heard a real case of bubbles in the veins, as far as I know. It sounds like the units may have gotten better if you can easily distinguish bubbles with your unit.

When the doppler guy was well enough to test us, he calculated that, diving to 220' on air he should see 2.3 cases of the bends and bubbling in all divers, or some such. We all wanted to be the .3 guy... He found very few bubbles, and actually called one of the divers a "freak of nature" because he didn't get bent on his profile.

John Yurga