I popped the stopper off of a red topped tube on an equine sample I was processing after being spun down, only to find the clot was stuck to it and pulled out as well, flinging blood all over the table.  I may have uttered a few choice words at that point and then went about cleaning up the mess and resetting the sample to be spun again…  There was plenty for sampling left, but situations like this happen all to regularly in the lab and are easily avoided.

I recently switched from working in the office to the serology lab at the animal disease diagnostic lab.  It may not be my life’s calling, but it has been a valuable learning experience, and those of you who know me know I promote owner submitted sampling for herd health checks.  Prior to this shift, I thought blood tubes were blood tubes, yes, different colored stopper lids indicate use for different testing, but lets go more basic than that and focus on Red Topped serum collection vacuum tubes.  These are the most commonly used and necessary for many animal health tests.  Basic tube construction, size, stopper, and label.  That’s about all they’re made up of.  You may ask, “So what?”, but the varieties of these components can help or hinder your sample quality as well as how the sample is collected.

1) Tube size.  This is pretty simple to figure out, look at the test to be done and the amount of blood/serum needed to complete it.  Multiple tests may need more, but usually in a very minuscule amount.  There is really no use in adding further stress to an animal and taking more of your time to bleed excessive amounts or fill multiple tubes that will not even be used for sampling.  Ensure you do take the minimum amount to properly mix with the additive, though.  Besides, at some point you have to put that sample in the mail, and less weight = lower shipping costs.

2) Tube type.  There are very few options, but glass and plastic.  Plastic can be more resilient if dropped or handled roughly, but in my opinion the clot does not from as well in plastic and that can raise the red cell count in a serum sample which can affect the end results.

3) Labels.  This is important and often forgotten, most tubes come with labels already adhered to them.  Before you leave the barn, and more importantly before you ever send it on it’s way, ensure it is properly and legibly labeled.  If you should have a positive, you’re going to want to be 100% sure you know where that sample came from.

4) Stopper.  There are several different styles of stopper, and they all seem to work as well as the next- as long as they are not removed prior to use.  The vacuum is lost at that point and the tube will not work properly.

5) Clotting. After sample collection, ensure lid is well seated and gently invert the sample 4-5 times for plastic (none for glass) to ensure good coverage of additive.  Let the sample sit for a minimum of 30 minutes up to an hour to allow for good clot formation.

6) Shipping.  As I touched on above there are a few points to consider when shipping and in addition to these, pay close attention to packaging.  A glass tube in a standard envelope will probably not make it to it’s destination in one piece.  Keep in mind, your name and address are on that package and any fines incurred for leaky specimens will be easily forwarded.   Ice packs are recommended in the hotter months, but generally not required other times of the year.  Use proper padding, bubble wrap or foam works well, but 25 layers of toilet paper really does not.

These are some pointers I have learned firsthand from being on the other side of the process from the producer, hopefully they can help you streamline your own testing processes.

For more information on different types of collection tubes and other helpful information, as well as products available, please visit: http://www.bd.com/vacutainer/faqs/