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I am in orientation as a traveler at an urban hospital and they have just told me they run blood through #22's and #24's. Ok, I know I'm getting old, but when did that start? I was always taught that it would lyse if you used one that small. I'm very uncomfortable with it. Are there new studies that say it's ok? Am I that out of date? Any input would be appreciated.
It is not a size thing but a pressure thing. The filter on most blood tubing is between 170-210 microns (much smaller than a 24 gauge). Blood cells fit through that without damage, the capillaries in your finger tip or smaller still.....
The issue is when you go from something the size of blood tubing down to a 24 gauge cannula, the pressure is what damages the cell. If the blood will flow to gravity you are OK. You may have to dilute with NSS in some cases. Most pumps are set at a pressure limit that, if it does not alarm, you are OK to pump blood. I agree with the idea BIGGER is better when pumping blood or fluid resuscitation but sometimes we take what we can get.
And please don't restick the little old lady with a good 22 gauge unless absolutely necessary.
Originally posted by Wendy Psych RNI graduated last year and nothing was ever said about running blood thru that small of a catheter. The blood cells would lyse if squeezed thru that small of a lumen.
Studies have been done regarding that matter and have found that there is little to no lysing unless the blood is being giving very fast/under excessive force.
Check with Am. Red Cross, but I believe they have stated it is ok to use 22 g., which I have done on elderly or any hard stick. ER and OR probably need faster infusion, however. Also depends on volume---4 pints would probably be stretching it. Have done 24 g with Bard pump (med infusion pump) for infants. Lysing is not as much a problem with fluids continually being infused.
OMG I can't believe this debate is still going on!
Blood cells will not lyse through a 24, or even smaller. They get through the snout of a mosquitoe, which is smaller than a hair. The problem comes when you go at a fast rate and the pressure required to get that amount of blood through a small opening will damage the cells. However if you just run it slowly there is no problem. Soemthing to do with Boyle's law, that connects pressure, diameter, and rate.
cab631
27 Posts
I've used 22's when I can't get anything else--doesn't seem to cause a problem. Most other nurses don't like it cuz of all the "hooey" out there, but it works just fine.