I know Halloween has come and gone, but I couldn’t resist evoking vampire imagery for this entry on phlebotomy, the art and science of collecting blood for laboratory testing. It’s simply too apropos — perhaps even more so when it comes to the vet version of this practice. I mean, when your work starts to look more like an episode of Dexter than a medical procedure, allusion to a little Halloween gore is probably acceptable.

That's not to say that veterinary phlebotomy is always messy. Indeed, it’s normally an uncomplicated affair unmarred by drama. The bloodletting usually runs smoothly — even with pets who'd prefer you didn't pierce their skin with a needle.



The process is simple:

  • Place pressure on the vein upstream from the site you plan to puncture to limit its flow and thereby make it plumper and juicier (by placing a tourniquet or applying manual pressure).
  • Wet the area with alcohol or disinfectant (shaving is optional, unless an indwelling catheter is required).
  • Find the vein by sight and/or by feel (palpate the vein with your finger to make sure it’s full and straight at the site you plan to puncture).
  • Puncture the skin and vein with one easy movement (it’s a Zen thing), and slowly pull back on the plunger.

Sounds easy, right?

Venipuncture, or phlebotomy (roughly interchangeable terms), is one of veterinary medicine's more basic procedures. But it's not necessarily an easy one. It takes months — sometimes years — of practice to learn to do it right. The goal is to harvest the minimum quantity of blood required in a painless and efficient manner.
 
Of course, it doesn’t always go according to plan. Like the time I was drawing a couple of teaspoons of blood for a feline allergy screen. The syringe malfunctioned and blood poured onto the floor. (It really was a freak accident that I’m sure I couldn’t repeat if I tried.)

Although 10 milliliters isn’t much, it appeared (to the uninitiated) as if I'd just exsanguinated this poor cat. Meanwhile, the slack-jawed owner stared, silent and ashen, as the blood pooled by her $500 Tod’s loafers. Needless to say, I didn’t make a good impression on her that day. And it’s no shock that I haven’t seen her since. 

This horror show experience was an exception, of course.

I can't say the same about my next example, which I’ve unfortunately suffered on multiple occasions. It sometimes happens that owners will become extremely nervous during venipuncture (and sometimes with any event that requires the use of a syringe –– with or without a needle attached to it). Although I do let everyone know when I’m about to perform a needle procedure, it’s been the case that owners have exclaimed, screamed and even passed out.

Of these, the screamers are the most unsettling. It’s happened twice to me — and both times I did not prepare an extremely sensitive owner for the reality of a jugular “stick.” Dogs in particular seem to react less to this approach than to the more common cephalic (forelimb) vein technique, but owners are not normally inclined to accept this fact. To them, putting a needle in the neck is just not pretty. However less painful, speedy and expedient it may be, plenty of owners are shocked by such an apparently violent clinical act.

Early in my career (before I knew how to identify and effectively mollify these special types of people), one owner even threatened to report me to the Board of Veterinary Medicine for animal cruelty. She swore she’d owned dozens of dogs and she'd never seen a veterinarian perform such an atrocity. The most irksome part of this experience was that the dog was a perfect angel, but he acted up whenever his legs were touched. I was really only doing what was best for my patient. I simply failed to properly consider the owner.

Then there are the common complications:

  • The vein sometimes does not reveal itself. Even with the pressure of a tourniquet, sick, dehydrated, fat or geriatric pets might have veins that don't lend themselves to easy discovery. Hiding in fat or depleted of pressure, these are the nemeses of phlebotomists.
  • In dog breeds with crooked legs (such as Dachshunds and Basset Hounds), the vein twists and turns, so that the needle bangs against the walls of the vein instead of staying in the middle, where the blood lives.
  • The vein is so teeny tiny and/or weak that pressure exerted by the syringe as it draws in the blood causes it to collapse (like when you try to suck up a thick shake through a straw).
  • Some veins just “roll.” These veins manage to move away every time you poke them. Plumper pets, in particular, are predisposed to this problem.
  • When it's the pet who's difficult to control, you have a moving target issue. Ever try to knit lace on an airplane during heavy turbulence? Even if you haven’t, you get the idea.


And then there are the anomalies, like my syringe malfunction. I’ll never live that one down. But, hey, life is a crazy ride you just have to roll with, right?