Saturday 7 July 2012

What are cannulas, PICC lines, femoral lines and hickman lines?

In order to administer drugs intravenously (via IV) you need to have some kind of thin tube inserted into a vein, so that the port(s) on the other end of that tube can be connected to a syringe/drip, thereby allowing the drugs to be inserted into the vein; It is also possible (sometimes at least) to use the same tube to remove fluids from the vein, e.g. to extract a sample of blood for testing purposes.



This is the simplest and most common method used, and typically involves inserting a small needle into a vein in one of your hands (on the back) or forearms (underneath - usually near the elbow).  If the veins are not very good there, then it is also possible to put them in your feet.  Once the needle is in a vein, a thin tube is slid into the vein and the needle removed.  The thin tube is connected to a small plastic port (at the other end) with what looks like a wing on both sides; The wings lay against your skin, and help with dressing the cannula, as thin strips of sticky tape can be placed over them to hold it in place.  Once secured, a dressing is placed over the area (leaving just the port(s) exposed) to keep it clean and help prevent infection.  It may feel a bit odd at first, but you soon forget about it.

If the idea of having a cannula inserted in your foot freaks you out a bit, then it may comfort you to know that despite the veins in my hands and forearms being hard to find these days, after all of the treatments that I've had, and that I've long lost track of how many cannulas I have had inserted in my hands and forearms, I've yet to actually have a nurse/doctor try to insert one in my foot; They have looked at my feet on a couple of occasions, but never went any further - I must admit, I was quite glad about that, as I don't really like the idea myself, and I have heard they're not very nice.

There are different sized cannulas for different sized veins too, so even if you have quite thin veins, it is still possible to have one inserted.  In case you are wondering, they are inserted without any anaesthetic, as you don't really feel it (certainly not enough to warrant local anaesthetic) and what you do feel tends to be over in less than a second.  As the nurse/doctor inserts the cannula, they will most likely warn you that the needle is about to go in by saying something about a "sharp scratch".

Cannulas are intended to be temporary, and will probably only stay in for anywhere between a few minutes and several days, depending on for what they are being used; The longest I've probably had one in my arm is around five days, after which it was starting to not work very well, so if it hadn't been for my treatment finishing at that point it would have likely been removed and another inserted.

Removing a cannula simply involves taking off the dressing, and pulling out the thin tube whilst covering the area with a small piece of gauze and applying some pressure to help it stop bleeding.  The gauze is then usually swapped for a clean piece and sticky taped down for a bit - It can be removed not long afterwards, e.g. normally you will be asked to take it off in fifteen minutes or so.



I have had a couple of PICC lines in the last few years; although they are intended to have much longer life spans than cannulas, in both cases mine were removed after about a week.  The first was removed due to getting infected, and the second was removed as it was only ever intended to be a temporary measure until a hickman line could be inserted.  When the PICC line got infected, you could see a kind of red line on my upper arm (following the path of the vein), and my upper arm felt quite hard; It didn't really hurt or anything, so at first I just assumed that was normal - I was wrong.

PICC actually stands for peripherally inserted central catheter, so it may come as no surprise that it is inserted in your arm (peripherally), but the thin tube for the line actually goes all the way up your arm and back down into a big vein near your heart (central); In both cases, mine were inserted on the underneath of my forearm near the elbow, which is fine except that it does tend to limit your arm movement, so it can be a bit awkward - Had mine stayed in longer, I might have got used to that.

Inserting a PICC line involves first using a cream that numbs the area where the line will be inserted; it is similar to having a local anaesthetic only it takes about thirty minutes to kick-in and you don't get any kind of stinging sensation.  Once the area is numb, you will lay down on a bed (if you have been admitted to a hospital ward, then probably just the bed you sleep in), your arm will be draped in those blue sheets you have probably seen in the movies, the area will be cleaned, the actual PICC line itself will be inserted, the area will probably be cleaned again (it tends to bleed a bit), and finally a transparent dressing will be placed over the top to keep it clean and help prevent infection.

The nurse/doctor inserting the PICC line does have to guess a bit whether the line is in the right position when inserting it, so an x-ray is necessary afterwards just to make sure it is positioned correctly.  Essentially, the line may need pulling out or pushing in a bit, or it may have taken the wrong path, e.g. gone up towards the brain instead of down towards the heart - A doctor did once tell me that you can kind of feel whether the latter is the case.  In terms of guessing the line length, it is calculated based on your height.  In the vast majority of cases, the x-ray will show the line is fine.

The PICC line itself looks like a tube going into your arm, which connects to a sticky plaster with the port(s) attached to it; I assume the sticky plaster is intended to prevent you from accidentally pulling on the tube going into your arm.  It does feel a bit odd on your arm at first, but you do start to forget it is there, and the white sock they give you to cover it all over does help take your mind off it too.

With the veins in my arm not being very good, it did actually take three separate attempts from different medical staff before my first PICC line was successfully inserted.  The first nurse tried in both arms, one of which was without the cream for numbing the area (it hardly felt any different), but was unsuccessful in both and was pretty gutted about it; to be honest, I almost had to console her!  The second nurse tried for quite some time (my arm must have been going blue), only this time with the aid of an ultrasound scanner, but she was also unsuccessful; to be fair, I think she had only just trained to do it, as a more senior colleague was helping her.  In the end, a doctor inserted the line without much fuss really; whether it was skill or luck, I guess I'll never know, but it was the same doctor that inserted the second PICC line several months later, and that went in first time too.

Removing a PICC line is a very similar process to removing a cannula, as it really involves the same steps, it is just that the tube is a lot longer (you will be surprised how long), and the dressing placed on afterwards needs to stay on for a while longer, just to give it a bit more time to stop bleeding.

Femoral Line


The femoral line is probably the most uncomfortable line that I have had, which is perhaps not too surprising given that it is inserted in the groin, but the actual insertion itself is a fairly straight forward procedure, and can just be done on a hospital bed, i.e. you don't need to go into theatre or anything.  I have had a couple of femoral lines in the last few years, and I have to say that the first one was much more uncomfortable than the second; With the first one, I kept managing to knock/pull on the line/stitches, which hurt a little (not much) and tended to make the line bleed.  To be honest, the second one was much better and didn't really bother me at all; It was positioned slightly higher-up, which probably meant that I was much less likely to keep catching it when walking etc.

Inserting a femoral line essentially involves draping the area with those blue sheets mentioned earlier, cleaning it to reduce the chances of infection, administrating the local anaesthetic, inserting the actual femoral line itself, and finally a couple of stitches to hold it in place.  The only thing that you feel is the local anaesthetic going in, which is just a slight stinging sensation.  With the femoral vein being somewhat bigger than those in your arm, it does tend to bleed when inserted, so the area needs cleaning before the dressing goes on, and you will likely need to clean around the dressing afterwards too.  You are covered over during the procedure, so only the top of your leg is exposed, hence you do get to maintain your modesty, so to speak; It is probably a good thing, as if you have had a fair bit of treatment, you may know the doctor quite well, so that avoids it being a bit awkward.  One thing I would say though is that it is definitely worth getting the area shaved (if necessary) before starting, as otherwise when the dressing comes off later on you are in for a not so pleasant waxing!

Removing the femoral line is similar to removing the PICC line, only: the stitches need to be removed before the thin tube can be pulled out; the gauze needs to be held on for a bit longer and with more pressure, so that the bleeding stops; and the dressing placed on afterwards is a bit more substantial, as it needs to stay on for longer due to the greater chance of some bleeding later on.

Hickman Line

I have had a couple of hickman lines inserted, one after my first relapse and the other just a few days ago after my second relapse, and whilst it does involve going into theatre for a minor procedure, which may make you feel a bit more anxious, I would much rather have my treatment this way than any of the other methods; the hickman line is neither uncomfy nor awkward, and it avoids the need for nurses/doctors to struggle to find my veins for retrieving blood samples or giving treatment.

The hickman line is a type of skin-tunnelled central catheter, and is in some ways similar to that of a PICC line, in that a thin tube is inserted and the end of it is in a big vein near your heart; The main difference is that instead of it being inserted in your arm it is inserted in your chest (just below the shoulder) - It is sometimes inserted in the lower neck, if it proves tricky inserting in the chest.

The procedure does take place in a theatre, but it is still only done under local anaesthetic, which is all it really needs, as other than feeling the local anaesthetic go in, and some prodding/tugging, you don't really feel anything - It is by no means painful.  With the procedure taking place in a theatre, due to the potential (albeit low) risks involved, you do have to sign a consent form before it can take place; one of the doctors will talk you through the potential risks to make sure you understand them, but it is really just a formality, as complications are rare, so you should try not to over think it.

The procedure begins with you laying on a bed (in a not so flattering hospital gown) that is tilted such that your feet are higher than your head, as this ensures that the blood is more in your upper body than lower body and consequently when any incisions are made the blood is more likely to come out of the incision, rather than air go into it.  Once in the correct position, the area is thoroughly cleaned with the yellowy brown fluid you have probably seen in the movies, and the area is draped with the blue sheets mentioned earlier; The blue sheets completely obscure your vision of what happens from here on in.  After the local anaesthetic has been administered, the insertion of the hickman line involves making two small incisions, one in your chest (just below the shoulder) or perhaps in your neck, and another a few inches further down your chest; the thin tube is tunnelled under your skin such that it comes out of the latter incision, and the former incision is ultimately stitched-up once the line is successfully in place.  The area can then be cleaned, have two dressings applied: one over the stitched-up area, and the other over where the line comes out of your chest.

Once the procedure is complete, you are taken to a post theatre room for maybe half an hour, where nurses can closely monitor your blood pressure, heart rate and oxygen saturation to ensure that you remain fine.  Also, just like with the PICC line, an x-ray needs to be taken to ensure that the line is positioned correctly; Again, in the vast majority of cases, the line position is fine, so you are soon on your way home (if you're an out-patient) or back to the hospital ward (if you are currently admitted).

About a day after having the line inserted, you do need to get the dressing that is over where the line comes out replaced, as it is does tend to bleed ever so slightly, or perhaps a bit more if you do anything too strenuous (you should try not to do much).  Also, after about seven to ten days, the other dressing and any stitches should be removed.  After that, any aching/tenderness should have long worn off, but you may still be able to see some bruising caused by all of the prodding/tugging etc.

No comments:

Post a Comment