Posted by Kendall Raine on November 01, 2000 at 16:12:53:
In Reply to: Re: Now where getting somewhere... posted by Frank, AADIVER, Farmer on October 31, 2000 at 21:45:51:
Frank;
Two issues in Dopplering yourself: 1) equipment 2) training.
Equipment. Hand held Dopplers can be had for $400-$600 w/probe from medical supply houses. I have a Huntleigh hand held unit which is used primarily to monitor fetal heart sounds and blood flow. I use a 5Mhz probe.
DAN and Karl Huggins use a fancier model they say is designed specifically for ultrasonic venous bubble detection. It's made by Teckno Scientific in Canada and sells for about $3500 with the probe. Karl says my model is ok for checking bubbles in the subclavian and proplteal sites but probably not precise enough to get consistent readings from the precordial site-at least not good enough for research or publication purposes.
Training. First of all I don't have formal training. I started checking myself years ago when I starting diving with Wings a lot and between that and studying the literature on Doppler grading systems, I know enough to tell which dives and deco schedules produce lots of bubbles and which produce few and whether the bubbles are helium or nitrogen. I would never advise someone else on deco based upon my own studies, but it keeps me amused. Sometimes I'll get bubble grades above 2 at which point I jump on the surface O2 for 30 minutes. That has always brought the grade level to 1 or less. Cheap insurance.
I asked Karl to teach me formally and he said he's not teaching now, but would give me some pointers sometime when he has the time.