Hi everyone, this is Lahiru from ABCs of anaesthesia.
And today, we are gonna go through vein selection.
As a general rule, you can really choose any vein you want, it’s just that some veins
has certain advantages, and other veins have certain challenges.
I would always go to the most distal site, that still satisfies the purpose.
For example, I’ve got this really long cephalic vein over here, now if I was to attempt cannulation
here and I messed up, then you would get a haematoma here and potentially clot inside
the vein, so I wouldn’t be able to use all of this segment here for any further cannulation,
and I would limit the options for future; whereas if I went here, even though if I miss,
I’d still have each of these other points of insertion, so I always say go for the most
distal site that still satisfies the purpose.
Now there’s broadly speaking, 3 main areas that you can cannulate on the arm, not counting
other parts of the body, these area are the antecubital fossa, the forearm, and the hand,
and on occasion I would also look at the arm as well.
Now if I look at the hand, these are one of the most common sites of cannulation, and
as you can see, my friend here who is very gifted with the amounts of veins he has, there’s
a lot of options with the hand, there’s also very easy sites to go into, you can get
a nice low angle with this site, lots of options, and you can get some big veins and small vein,
so very common site to go for.
Now the challenges are that often the veins aren’t big enough for the big resuscitation
cannula, and if the patient is in hospital for a few days, they are not gonna be able
to use their hand to full extend because the cannula probably impede that.
Now the forearm is a really great site, often there’s really big veins that you can put
really large cannulas for resuscitation into, and it’s also very comfortable for the patient,
for example the patient can still move their hand, and also move their elbow without blocking
the flow of any fluid or medications.
It’s kind of an advance area because you can’t always get the low angle that you
require to get those really cannulas in.
Finally one of the most common sites of blood taking and cannulation, is the antecubital
fossa.
Now, this is probably one of the first places you will learn to cannulate, as the veins
are superficial, and they are quite large, and so it’s quite an easy way to start out.
Now those are great reasons to try the cubital fossa, but unfortunately there’s also some
challenges.
There’s a lot of structures there such as nerves, arteries and tendon that you might
accidentally impinge on, and that is something you really want to avoid.
For the patient, after being in the hospital for a while, they will be really annoyed not
being able to bend their elbow as well, bending the elbow with cubital fossa vein means they
might not be able to get flow of that fluid and medications that they need.
Now the next thing I wanna go through is whether to choose the left, or the right hand.
There’s a few factors that are influence this, including patient preference, logistics
of theatre, and also the surgical access.
So with patient that are right-handed, I generally want to put the cannula in the left hand,
that means with their dominant hand, they are able to use it freely without much hassle.
I’m always thinking about the logistics of my anaesthesia induction.
For example, in my theatre setup, the anaesthesia machine is on the right hand side of the patient,
which means there’s a whole lot of stuff there, including my assistant.
Often I’ll be standing here on the left hand side, while my trainee or my assistant
is doing the airway management.
So I want to be able to give medication easily without having to reach over the patient,
so left handed cannula is great depending on your anaesthetic setup.
Finally I’m always thinking about surgical access to their case.
For example, in Lap Chole, both arms are out, they are not against the body, they are outwards.
This means that I can really have access and observe where my cannula is for the whole
surgery.
However some cases like Lap Appendicectomy, they want the left hand in, and the right
arm out, in that case I might opt to have the right arm as my cannulation arm.
Then there’s other procedures like gynae surgery where both arms are in, and in that
setting, I just leave the cannula in the left arm anyway.
So hope you enjoy that, there’s all the things I go through my mind when I try to
choose a vein, I’m trying to choose which site I’m gonna put it in, whether there’s
left or right hand, I’m trying to think of the logistic for the theatre and for my
anaesthetic induction, and also what the surgical preference will be, and thereby make my decision.
What you’ll find is that you’ll be able to go through these and see certain patterns
and trends, and always get your supervisor to assist you in deciding as well.
Thanks very much.