A stab in the dark…

Fluid therapy by cannula

One of the most common procedures in veterinary medicine is placing an IV cannula – a little plastic tube with a needle in the middle that can be removed after it is placed that goes into a vein to allow us to give drugs straight into the blood.  It is something that looks so easy, yet can be the most frustrating thing in the world when it just doesn’t seem to want to go where it should.

Now I’ve been given a chance to try a few times, and sometimes it has worked first time, sometimes the second time, however I believe in the 3 strike rule so if I cannot get it on my third attempt it is time for someone else to step in. It’s not just the physical act, but the frustration that comes from something so simple being such a pain – and I am not alone – from what I’ve seen everyone that does it struggles at some point.

Sometimes patients can be extremely difficult if they won’t stop moving… Or if they are sick (duh!) and the blood pressure is low because of things like dehydration. In humans in this case they have intraosseous needle drills where they can drill a cannula straight into the bone – the blood vessels in the bone are good as the bone gives them structure. However here it is rarely used, and especially not for routine patients that are not in life threatening situations.

Today however I did something different, to this point I’ve made sure that all my attempts have been where I can physically see the vein I want to get into. However after shaving the patients leg today I realised that I could not see the vein – and there was only 1 doctor working busy with another patient. I know the anatomy so knew where it should, and I thought I could feel the bounce of the vein in relation to the firmness of the muscle. So I tried, and I got nothing. Pulling back on the cannula slightly I redirected the needle a fraction of a mm and saw a flash of blood in the hub – I pulled the stylet (middle needle that is used to place the cannula) back and slide the cannula all the way in. I then flushed it to make sure it really was in the vein and not just under the skin and that being good fixed it into place.

It would never be that simple however as the next patient up was a cat that had trauma. Though I could see a massive big vein it took me 3 attempts to get the cannula into place…

My first cat cannulation… (Day 531)

Today’s Diary Entry is sponsored by Rabbit Feeds

So today started badly as because of the Norwegian program my Falconry and Wildlife Rehab lecture was cancelled leaving me with just patho physiology and parasitology lectures followed by my general surgery practical. Well so though I have seen plenty placed, I’ve never actually got to place a cannula into a cat before. Something about my first ever attempt being in front of a owner, on a sick (and very stressed) cat, with the associated pressure always kinda gave me pause. Not to mention the claws and teeth that cats possess!

Today’s general surgery class was all about how and where to give different injections using various techniques (on cadavers). A few of the group were then allowed to attempt cannulation – basically inserting a port into the vein which is then kept there as long as needed. Now someone in my group tried the vein lower down and failed, which caused a hematoma (bruise). So my attempt was a little higher than I would normally like – you are supposed to try to avoid joints etc – however as no one else jumped forward I decided to give it a go.

Now I found blood straight away (meaning I found the vein), however trying to get the cannula into place I lost it. Basically this part is really fiddly as a cannula is basically a silicone tube over a metal stylet, once you are in the vein you need to push the tube in further whilst taking out the stylet… This is a lot more difficult then it sounds one handed. So after going a little wonky beside the vein with some fiddling I managed to get it into the vein properly. Now this meant I then had to fix it in, so using the sticky tape I had prepared I attempted to do this, so I found that this is also more difficult than I expected – added to the fact I think I cut the tape strips too long – so it didn’t look as pretty as it could have, however it worked.