If you can drive it the vet's office, that would be ideal. Its not the refrigeration that is the critical step; its the separation of the blood's components by spinning the sample in a centrifuge that is. The separation has to be done no later than 4 hrs after blood is drawn from the horse. So, if your vet has add'l appts after yours, or gets an emergency call he/she must take, the blood wont get spun in time.
After spinning the tubes, the separated sections of blood have to be carefully extracted by hand and placed into a different type of blood tube and (ideally) frozen until shipment. All of this is delicate, tedious work that should be done within the 4-hr recommended window to have the most accurate results. So while refrigeration is important, its not the only part of the handling--the bulk of the work in prepping the blood sample happens in the vet's clinic, usually by his/her vet techs ;)
As for the initial transport of the tubes after drawing--the "purple tops" w the purple stopper have an additive that prevents the blood from clotting so you want the blood in those tubes to stay gently mixed together (ie, doesnt matter if theyre flat on side, standing up, etc). This is the sample for testing the ACTH (PPID status) and the one that must stay cooled.
Usually another tube is drawn with a red stopper; this one does not contain an anti-coagulant so the blood is supposed to form a big yucky clot in the bottom and a yellow liquid will separate itself out on top of the clot. Thats exactly what you want to happen. Yes, ideally, the tubes should stand upright but its not crucial for the results--you just dont want to disturb the clot in the tube once its formed (usually w/in 10 mins of draw) so if the tube accidentally falls on its side, no big deal, just leave it that way until you get to the vet's office. You should keep these red-top tubes chilled also but its not as critical as it is for the purple top tubes.
The red tops will be spun and serum will be extracted similarly to the purple tops.
-Blood tubes need to be cooled, centrifuged, & separated within 4 hrs of drawing from horse. So unless yr vet brings his centrifuge with him (usually they do not) then yes, you should drive the blood tubes to vets office.
-Purple tops must be kept cool. These samples can be gently mixed or ride to the clinic on their sides; no big deal. They are not supposed to clot
-Red top tubes ARE supposed to form a clot on their own and ideally stand upright & remain undisturbed during transport. Its not a problem if the tubes fall over; they're going to be spun at a high rate of speed to separate the cells anyway so no real damage is done if the blood mixes/clot moves. You might see a remark about hemolysis in results (means some red blood cells ruptured but its not going to effect the leptin or insulin results; if you're running a blood chemistry to check on body-wide organ system function then possible hemolysis would potentially interfere with results). Best to keep the red tubes cooled also.
Im not going to get into the glucose part of the Cornell panel. If your vet is requesting the glucose test & you handle the blood tubes as Ive described above, the glucose results will be fairly accurate.
Kerry in NY
Licensed Vet Tech