I have a new Fresenius 2008k. When I tested the bicarb(38) I recieved results back indicating the bicarb was only 29. I calibrated the acid and bicarb pumps two times and still get the same result. Any solutions out there? P.S. I am a rookie, lol.

Where are you getting the sample from? Make sure the machine has been running for a good amount of time up in conductivity. Also make sure you using good bicarb and not some that has been in a jug for a week.

I get the sample from the hanson. I do bring the machine up in conduct. and let it run for 10 minutes. The bicarb is fresh.

As far as I know bicarb is measured by measuring the CO2 in solution and the CO2 will degas. IMHO, the only way to accurately get a level is to test it on-site some way. Also the "bicarb" of 38 is actually the sodium contribution to the dialysate and not the amount of bicarbonate which if I remember correctly is listed seperately on the bag/carton.

Chuck

Had this same problem this month. We are on a central bicarb loop. I finally got a good result
after 3rd draw. I think it was inconsistant mixing of the bicarb by the PCT's. I would check the bicarb in the holding tank for correct specific gravity and/or conductivity depending on what kind of insterment you use at your clinic, before you draw your sample. It worked for me and I quit chasing my tail. LOL

Make sure the person mixing the bicarb isn't letting it mix for 30 minutes. This will cause a de-gassing of the mix and your bicarbs will be wrong all the time. Also, I don't know how you send off your samples. When I had to inject a vacutaner with solution, I would always push a little more in to make it positive pressure in the tube. Now that I am putting it in a screw off tube, I fill it all the way so there is no room for off gassing in the tube. Remember you have a very small sample. There is pleanty of room in an half filled tube to off gas and give you low results. I hope this helped.

I also had a problem this month. Sent 3 samples taken at 38 bicarb. I recieved results at 30. All the other electorlytes were good.
tbear what lab are you using?

Careful Biomed Dude, just a little more positive pressure and the rubber stopper blows out and OH! what a mess.

I am curious if you are mixing one bag Naturlyte bicarb powder with 25 gallons of water. Technically, the water level should be 25 gallons after the Naturalyte has been added to the water. I have the same problem with my bicarb, and I believe the bicarb is diluted approximately 4% when it is mixed this way.

Who do you use for your labs? I use Nationwide and just last week, I got back my labs from 5 machines and everyone of them is way low.

I use Spectra Labs. Turns out it was the factory calibration of the balancing chamber. Like I said, I'm a rookie. Thanks for all of your help!