You know when they take blood with those “reusable” needles? Not that the needle is reused, but they stick you once then switch out the glass part several times.
Are those glass parts vacuumed? The blood seems to really ‘squirt’ into them and they don’t seem to have a problem with air being displaced.
And you should know that most of these tubes are not sterile on the inside. It is important to avoid reflux of blood back into the vein. This is why the tournequet is released before the blood draw is complete, and the arm must not be raised…otherwise backflow may occur.
All the vacutainer blood collection tubes used at our facility are sterile. Lavender top, gray, red, blue, speckled red/green, red/gray, etc., all of them. And we use the standard collection tubes like every other hospital I’ve ever been in.
Could be you might not want the additive inside some of the tubes to flow out, but they’re very small amounts. I’ve never heard of this doing any harm to anyone. The tourniquet has to be released before you withdraw the needle or else you get a nice blood trail oozing out down the patient’s arm. This doesn’t make them very happy. (I only did it once, I swear.)
The inside of most of these collection tubes are NOT guaranteed to be sterile, and the recommendations to avoid reflux during collection are primarilly because of that fact. Even the Merck Manual mentions this fact in their Hematology section.
All our tubes used with the vacutainer system are Monoject brand and they all have “Sterile” imprinted upon the label. I’m inches away from a pile of them as I type.
'Scuse me. I just checked supplies and it appears we use three different types- Monoject, Corvac and Vacutainer. But all the boxes and apparently all the tubes (I didn’t look at each one) are labeled Sterile.
And as some of them are used for blood cultures they better not be lying to us.
All I can say is that this information seems pretty out-of-date as neither I nor any Medical Technologist I know have used, or seen for that matter, blood collection tubes that weren’t sterilized. For what it’s worth, in my case that means for the past eleven years.