You must first understand the purpose of the torniquet.
When you tie the tourniquet for IV, you're tying a Veinous
Torniquet;means you tie just enough to stop the blood from flowing
back to the heart. Therefore, veinous blood from the tip of your
fingers to the point where you tie the torniquet, will flow slowly
through to the point it will stop flowing.
As you know blood flows from the heart to other parts of body via
Arteries and from other part of body to the heart via Veins.
So, when the body detects that one of the vein does not have blood
flowing back to the heart as fast as it should (due to the
torniquet), it will adjust the blood flow by redirecting the blood
to another vein with a much faster flowrate, thus causing the vein
with the slow rate of blood flow will have less blood passing
through it. Eventually, the vein will collapse.
That is why, you are not advised to tie the torniquet too long. And
do not tie your buddy's arm, and wait for your SGT to come and
watch you do. Only tie when he is ready and sitting beside
you.
So. identify the vein first, then tie torniquet, swap and carry on
IVing, don't waste time.
"Topo"ing is not an overnight skill to learn. It comes with
experience. Usually, whenever people have "one-Shot-One-Kill"
during IV Practice session in BMC, I don't usually give them that
much credit. I prefer trainees to miss, then able to find back the
vein and manage to get backflow; Now that's how you guys should
learn IV. Always vary your buddies with each IV session, ranging
from visible veins to barely visible to can't-be-seen veins.
Basically, topo-ing is when you can't hit the vein the first time
you poke, and then with the needle still in the arm, try to find
the vein with your other free fingers and guiding the needle to
that vein. Sometimes you just need to turn the needle a few mm to
the left/right; sometimes you need to lower/increase the angle of
needle to the skin. But do realise that once you start to topo, you
better find the vein fast as the the vein may collapse very fast
due to prolonged torniquet tying.
Always remember, even if you managed to get "one-Shot-One-Kill" for
all 10 IV practices in BMC, if does not mean you will get it again
during your first IV to a real-life casualty.
--> I feel like I was giving IV lesson at Training Shed 702..
lol
