The Port-a-Cath

Category: Daily Thought





What is a Port-a-Cath?


I’m glad you asked.  I accessed one  today.


A Port-a-Cath, or "port" for short is an implanted central line or IV access device whose access end is buried beneath the skin.  These access devices are usually in the chest wall but could be found in the groin or abdomen also, though I’ve only seen them in the chest.  They are usually installed in  people who need long term medication given by the IV route, often cancer patients on chemotherapy or someone who has a chronic infection that must be on long  term, frequent doses of antibiotics will have one installed by their doctor.  It's an outpatient procedure done under local anesthesia and perhaps a light sedation. The port looks like the priming  bulb on my lawn mower with a tube attached to it.   The tube enters into the large vein entering the heart, the Vena Cava and  stops just short of entering the heart’s atrium, the top most  chamber.

At the other end of the tube is the little port.  It consists of a silicone  diaphragm over a small volume, flat backed chamber that is sutured to the muscles beneath the skin of the upper chest.  It is palpable just under the skin.  The better you can palpate it, the easier it is to access.  On obese people, accessing the small port can be a hit or miss  affair.  However, if you need a Port-a-Cath installed, you are probably pretty skinny  from being sick.  Having the port  buried under the skin decreases the incidence of infection.  When not being used, the port is  safely tucked away, unlike a regular IV or central line, whose access end is out in  the air being vomited on and rubbed in poo and everything else.


A special needle is used to access the port; a Huber needle.  The needle is non-coring,  meaning it will not pull any material out of the diaphragm.  If the diaphragm gets a hole in it, it would be ruined and allow medicine to escape the port into the tissues of the chest.  Having chemotherapy toxins leek into your chest wall would probably kill you.  The port is accessed in a sterile fashion since introducing bacteria into the device would defeat the purpose of having it installed in the first place.  Huber needles are shaped like an L.  They come in various sizes to suit the patient.  They can be of different lumen sizes as well as length.  The usual size is similar to a 20 guage IV needle bent at a 90 degree angle.  This angle probably also makes it difficult to over penetrate and puncture the lung.


We frequently access ports in the ER to draw blood and give medicine.  Accessing a port is kind of fun to me.  You get to make a big production with sterile gloves and masks and all.  After carefully palpating the device to locate it and thoroughly disinfecting the skin above it, you firmly push the needle into the port until it hits bottom.  Until you’ve jammed a big needle into someone’s chest, you just can’t know what it feels like… It was kind of scary the first time, to be honest.  I really felt like I was hurting the patient and of course that upset me a little.  However, after a few times it gets really easy.  The hard part is getting all the equipment together and getting everything set up.  Once that happens, the actual accessing is a cinch.  The last one I accessed the person said, ”You’ve sure done this a lot.” Which I took as a compliment. Being thorough in my preparation and sure in my actions sends a sense of competence to the patient and keeps them from being worried during an unpleasant procedure.  Let's face it, if you have a port, you need all the competence you can get out of your healthcare providers.  I got the idea that for this person, the care providers weren't actually gowning up and putting on masks and stuff.  I was taught to use gloves, gown, and mask.  The patient gets a mask also if they can tolerate it so no one is blowing their breath down on the site while it's being accessed.


There are several different kinds of ports and Port-a-Cath is just one of them. Some require flushing with a heparin solution when de-accessing and some only need saline.  De-accessing them consists of flushing them out, clamping them off and simply pulling the needle out of the diaphragm.  Just a bandaid is applied. It’s important to flush them out or a blood clot will form in the tip, making them useless.  Never apply pressure to flush out a clotted off catheter.  By pushing out the blood clot into the patient’s circulation, you are playing Russian roulette with that person’s life.  Like throwing a yard  dart up in the air as high as you can…you never know where it’s going to land, but where it does, there’s going to be trouble.


Here are two pictures.  The  first one shows the front view and the second one shows the side view.  The tube can clearly be seen going up to just below the collar bone, entering into the vein and then threading down to the tip of the atrium.  Disregard the yellow arrow in the top picture. There is also an electrode lead on the patient.  Can you see it?


     


www.EmergencyDpt.com



What do you do when your patient's catheter won't give blood?  This is a frequent problem.  Basically, I've found three things that cause a port not to give blood.  Either it is up against the vessel wall or "positional": It's got  small fibrin cap on the end acting as a valve, or it's clotted off.  The first thing I do is ask the patient if his or her cath normally gives blood.  Sometimes they don't and the person knows it.  So if it normally gives blood but it's not today, then I get them to reposition themselves to see if the tip is against the vessel wall.  You can try raising the arm over their head.  This often works well.  You can also ask them to flex thier shoulders in and out like they are flying.  You can ask them to lie on the non affected side if they can tolerate it.  If none of those things works and it is still flushing ok, then there is probably a fibrin cap or small clot over the end acting like a valve.  It will soon clot off the rest of the way.  Make sure you flush it according to protocol and make sure the patient follows up with their doctor.  If it clots off all the way, it can sometimes be salvaged with a small dose of TPA or tissue plasminogen activator.  This is the same drug they give to heart attack victims, the 'clot buster' that opens up blocked arteries.  It's just given in a very small dose to clean the catheter.

I haven't used this yet.  At Kaiser, they give the ER nurses a 15 minute inservice on how to use the clot buster in this application.  I took the inservice and it looked very simple.  You apply some suction to the port, then work to instill a very small amount of the drug to replace the volume you sucked out.  Then you wait.  Repeat until the catheter flushes.  Simple as pie and a lot easier on the patient than having the device replaced, that's for sure.

So that's the skinny on ports.  I hope it is of some use to you.  If you have any questions about this or any other article on this blog, you are welcome to ask.  I am here to serve.

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Posted by Emergencydpt at 4/17/2008 1:40 AM
Categories: Daily Thought
 

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  • 5/27/2009 12:04 AM rachel wrote:
    Hi! My 18-yr old son had a terrible experience when his portacath was accessed. After an hour and without the IV line yet, he started getting chills, had a high fever, and a blood pressure of 150/90, his lips started turning blue. This went on for about 3 hours before he returned to normal. The doctor said it was probably due to a clot that didn't dissolve when it was flushed and that the flushing should have been done more slowly. Another doctor said that the clot was left-over from the last time and shouldn't have formed if enough heparin was given when the needle was removed.

    Can you tell me what caused this and how could it be prevented?
    Reply to this
  • 7/17/2009 3:07 PM Maria wrote:
    I'm having a problem with blood coming from my port I have had in for 5 years....He said I may have to have an xray. They said there may be a veil forming around it. Great--I don't have enough problems.
    Reply to this
    1. 7/17/2009 6:23 PM Emergencydpt wrote:
      Hi.
      Thanks for your comment.  I'm sorry you are having trouble with your port.

      There are several species of problem that can cause a port not to give blood.  A sheath, a flap, a clot, or malposition.  The first three can often be fixed with a short procedure where a small amount of clot lysing medicine is instilled into the port.  The last one is more problematic.

      A sheath can form around the tip of the catheter, blocking it.  A flap or veil can form and act like a one-way valve over the tip.  A clot can form within the lumen of the catheter when blood enters it, either through poor technique during use or simply through the process of diffusion.

      Malposition of the catheter tip happens when the tip migrates; either up against the vessel wall or in some cases it can actually penetrate the vessel wall and end up outside the circulatory system all together.  This is obviously a serius problem.

      The first thing to do is to try changing your body position during syringe withdrawl to see if the tip of the catheter, if malpositioned, can be encouraged to move to a better position.  Sometimes laying on your side or raising your arm on the cather side, moving your shoulder back and forth can cause the tip to move away from the vessel wall.

      In any case, instiling anything into a catheter that does not give a blood return is against reccomendations.  Pushing fluid into a clotted catheter can dislodge the clot, causing it to travel into the lungs which can be fatal.

      At our hospital, the protocol for flushing the port after use is to flush with ten cc syringes of saline, twice, using a pulsitile method (stopping and starting) to create turbulance within the lumen.  That is followed by five cc's of 100 units per cc heparin flush, locking the clamp on the down stroke so there is not a back flow as the syringe is withdrawn.  We also use a positive pressure needleless syringe clave; also stopping negative pressure from causing inflow of blood.

      It must be remembered that heparin does not break up clots.  It only keeps them from forming.  A TPA product called "Cathflow" is used to break up clots in ports and other central venuous access devices.

      The fact of the matter is that the body does not take kindly to implanted devices.  They are frought with risks that must be wieghed against the benifits recieved.  You've gotten five years and been saved many minor injuries from peripherial IV starts with your port.  Even regular IV starts can and sometimes do cause serious complications.

      The department head at one ER I worked at caused a woman to loose part of her hand when he injected a routine but harsh medicine into a blown peripheral IV.  This caused vasoconstriction, and blocked the blood supply to her hand.  Her care was already incredibly complicated and the pain and suffering she went through during the ordeal and the physical and mental scarring she sustained as a result wieghed heavily on the moral of the department and of course her own.  We soon put together new protocols for injecting this medicine that have since been adopted in many other facilities.

      I'm glad you are researching your care and hope this problem is resolved safely.

      Be well,
      Spencer Miller RN

      Reply to this
  • 7/18/2009 11:39 AM Maria wrote:
    Dear Spencer Miller RN.
    I can't tell you how much I appreciate the information you have given me. This information is very valuable to me since I am completely lost and in the dark. Thank you for spending your precious time to inform me of my serious problem. I know I have great nurses and Drs. but sometimes want to blame them. I'm going this Wednesday for the procedure and pray it will be fine. They do use Heprin or something they inject into it which within a half hour allows them to draw blood. It's just a very scary procedure.
    Again, I can't thank you enough for your response.
    Sincerely,
    Maria
    Reply to this
  • 9/24/2009 12:53 PM Maria wrote:
    Please help again. They are telling me my port does have a sheath over it and to go to have the sheath removed by using a wire going to the groin area which I really would rather not take the chance of doing. I have some appts. with General Surgeons to discuss some of my questions but was wondering if you ever heard of them just removing the old port and using a new one. Like I told you in the past this one has been in for 5 years and I read they usually only last 2-5 years. Wouldn't you think it would be better just to replace it instead of going through that risky surgery with a wire in my groin. For some reason the Drs. seem they don't want to replace it. If I have them do the wire I have a feeling it will have to be replaced anyway in a short period of time since it has been there for several yrs for my Chemo treatments. Please help
    Thank you in advance,
    Maria
    Reply to this
    1. 9/25/2009 5:55 PM Emergencydpt wrote:
      Hi Maria,
      Thanks for your email.  I'm sorry you are having trouble with your port.
      Please remember that as an ER nurse, I am not really qualified to give you advice on how to proceed.  My expertise involves accessing ports only.  That being said, I think I can discuss some of the ins and outs of your choices.

      The first thing to do is see if the sheath will respond to Alteplace or Tissue Plasminogen Activator, the clot busters.  This is usually the first step in fixing a clotted off port.  Think of it as Draino for the port.  The procedure is simple and no more invasive than your usual port accessing.

      Having done that, the next less invasive procedure would probably be what your doctors have suggested.  It is much easier than replacing the port.  I will have to ask someone about the exact mechanism for removing the sheath from the distal end of the tube but I would imagine that any  danger revolves around having the clot break free and travel to the lungs.  This danger would probably be higher if you simply tried to remove the port altogether.  Pulling it out of the vein would tend to strip the clot off, allowing it to float free and travel.  That would be bad news.

      The only other danger I can think of for the IR (interventional radiology) procedure with the wire in the groin would be accidentally perforating the blood vessel.  I would think that would be extremely rare; a very small risk.  It's done using a fluoroscope so the wire and the catheter are visualized all the time.  You will be lightly sedated and the groin area will be numbed up first.  Then a needle, really not much bigger than a regular IV needle will be inserted in the large, straight blood vessel in the groin.  It's a very small hole.  You have no sensation of the wire moving through your body.  I would assume the clot is vacuumed off the catheter or otherwise destroyed.  Once again, I'm not exactly sure of the procedure but it's much less invasive and less risky than replacing the port; less scarring also.   Of course, post operative bleeding and infection are always possible problems, but they can happen just by accessing the port.

      If that fails, then another port may have to be installed.  You always want to go with the most conservative treatment first because all procedures have risks associated with them.  The more invasive, the more risk.  Pulling out the old port, possibly dislodging the sheath, then putting another one in, tunneling the catheter and the diaphragm assembly under the skin, sewing it all down under an area already with scar tissue over it adds risk.  And of course it could easily develop a sheath again.  It would be easier to just periodically strip off the sheath then to keep replacing the whole port.

      While no choice is without risk, only one choice will be right for you, for your level of comfort with the procedure and with your treatment goals.  So a careful consideration of the risk of each procedure vs the benefit will bring you to the correct conclusion.  I hope this helps.

      Wishing you health,
      Spencer

      Reply to this
  • 1/4/2010 9:28 AM Web developers wrote:
    That was an inspiring post,

    I have never ever heard of one of these portacath's before...

    I dont quite understand how it would work... and how does an L shaped needle work... it just brings pain to mind tbh...

    Thanks
    Reply to this
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