Dialysis Access, or What You Need To Be On Hemodialysis

Kidney failure that is permanent is called chronic renal insufficiency.  There are 6 stages to kidney failure,.  When you get to stage 5, you are much closer to ending dialysis. Your kidney doctor (nephrologist) will decide with you when its time to start dialysis.  When to start dialysis really depends on a constellation of your symptoms (shortness of breath, nausea and loss of appetite, leg swelling) as well as the lab work.  In general, when you kidney function is heading down below 10-12%, you are getting close to needing dialysis.

There are two ways of dialyzing, namely hemodialysis (blood dialysis) and peritoneal dialysis (dialyzing with a catheter that is placed in your abdominal cavity).  We are going to deal with hemodialysis today.  In order to have hemodialysis, you have to have a way to take the “dirty” blood out, pass it through the kidney machine, and then put the “clean” blood back into your circulation.  This can be achieved by wants called an arteriovenous graft (AVG) or an arteriovenous fistula (AVF).  Simply defined, an AVG is where we put a prosthetic material to connect an artery to a vein, and an AVG is when we connect one of your veins directly to an artery.  Essentially, we are creating a high flow conduit that can accessed for pulling blood out of the circulation, and retiring it after putting the blood through the kidney machine.

An AVF is the best way of creating a dialysis access.  When we create an AVG, we don’t put any prosthetic material into your body.  We connect a vein in your arm to an artery, and create a low resistance pathway for blood to flow.  Remember arteries bring blood down to the hand and veins take blood back up.  When we sew a vein onto an artery, part of the blood flow that is going down the artery goes immediately back up the vein. In time, the vein gets bigger, and develops a stronger thrill (a “buzzing” feeling or vibration that you feel when you put your fingers over that area due to the rapid flow of blood in an elastic vessel).  Fistulas can be created in the forearm at the wrist or in the upper arm.  We always perform a preoperative ultrasound evaluation of the veins to assess the ideal site for creating the AVF, and I usually repeat the ultrasound at the time of surgery to conform the preoperative evaluation.  The surgery itself takes about an hour to perform as an outpatient, and is not particularly painful. Once you recover from the surgery discomfort, you can use your arm like normal, including weight lifting and exercising.  The advantage of the fistula is that is tends to last longer without clotting, and has a very low risk of getting an infection.  The downside of an AVF is that is takes 6-8 weeks to “mature” or get ready to use, and sometimes needs a revision because of narrowing in the fistula, or development of large side branches that steal blood from the main body of the fistula.

If your veins are small or scared up from previous blood draws or I.V’s we sometimes will use prosthetic material to create the connection between the artery and vein.  The most commonly used prosthetic material is polytetrafluoroethelene (PTFE).  In essence, we create a pathway for dialysis by tunneling the PTFE under the skin in a straight line o a loop to connect an artery that supplies blood to the vein that takes blood back.  The surgical site has to heal for 2-3 weeks before it can the used.  In this situation, blood is taken out of the PTFE on the “arterial side” and returned after passing through the dialysis machine on the “venous side”.  The advantage of an AVG is that is can be used within 2-3 weeks.  the disadvantage is that it tends to clot more often and may have to  be declotted, and it has a higher risk for infection.

The reason your nephrologist refers you to us as vascular surgeons before you might need to start dialysis is so that we can create an AVF or AVG well ahead of time. If you don’t have an AVF or AVG ready to use, and you need to start dialysis, we have to place tunneled catheters that hang out of your skin to use for dialysis immediately.  It has 2 openings or ports, one to pull blood out and put it into the kidney machine, and the other to return the cleaned blood back to the circulation.  Remember, there is nothing hanging out of you with an AVG or AVF.  Tunneled catheters are what we would like to avoid if at all possible.  First of all, its a nuisance having a piece of plastic tubing having out of your chest area.  you can’t shower properly, and it hangs up on your clothes, and can sometimes be accidentally pulled out.  But the bigger concern is that it is a piece of plastic tubing that is tunneled under your skin that ultimately ends up inside one of the main veins that drains towards the heart.  It is an invitation to getting an infection. If we place these tunneled catheters (sometimes called permacaths), we would like to remove them as soon as possible to avoid the potential complications.  That why it is far better to have an AVF created way ahead of time, even if you don’t need dialysis for 6 months, so that it will be ready for you when you need to start hemodialysis.

One final word on hemodialysis.  Typically, you need to go to the dialysis center 3 times a week for 4 hour sessions of dialysis.  However, more and more patients are able now to get dialysis machines at home, and so home hemodialysis is becoming a good option. I will discuss peritoneal dialysis at a later time.

Maktub-Air of Resignation or Sound Advice?

One of the words that really interested me in The Alchemist by Paulo Cuehlo was the Arabic word “Maktub” which apparently means “so it is written.”  I think it really loses it full flavor when translated from the Arabic.  Even the pronunciation of the word gives it more meaning than you can get by literal translation, but I guess thats what you lose when you translate one language to another.  All the pronunciations of the word I can find on the internet sound like an American or European reading the word MACK-TUB.  I would love to hear it from an Arabic speaking person to get the full flavor.

Does the word mean “so it is written” as in “there’s nothing you can do about it” or does it imply “young man or women, take life one step at a time.”  I would prefer it to imply the latter, but thats probably my own personal bias.  Life seems much more hectic than it used to be.  Every event and statement has taken on an air of so much importance and relevance.  But perhaps as Charlie Munger might ask “what is the incentive for these peoples motivation and behavior?” I tell my kids there are only 3 or 4 really important things or events in life, kind of like the 10X inflection points that Andy Grove wrote about.  These include controlling your mind and thinking, when and to whom you get married, and when and if you have children.  A loving atmosphere at home is the foundation for your life.  The rest of it is probably nonsense.  The other thing I tell my kids is what my Dad told me years ago, and it has always stuck in my mind.  He said “I can tell you about a man by the people he hangs out with.”  Thanks Dad, that was good advice.

Carotid Artery Disease and Strokes

The carotid arteries are the main blood supply to most of the brain.  The right carotid artery supplies the right side of the brain.  A right sided stroke  symptom will include loss of vision in the right eye, kid of like those old movie theaters where a curtain comes down over part of the eye or all of it.  This event is called Amaurosis Fugax.  Another potential symptom of a right brain stroke is loss of motor control of the left side of your body.  You may be stirring a cup of coffee with your left hand, and all of a sudden you can lift your hand.  There is no pain associated with these events.  A left brain stroke will cause the opposite event to the right side, namely amaurosis fugax of the left eye and loss of right sided motor control.  In addition, most peoples speech centers are on the left side of the brain, so you may lose your ability to speak even though you know what you want to say, or it may come out as a string of non-sense words.

Carotid artery blockages are one of the many potential reasons for a stroke.  The risk factors for carotid artery disease are the same as the risk factors for other cardiovascular diseases.  These include   1.  Cigarette smoking

2.  Diabetes

3.  High blood pressure

4.  High cholesterol or triglycerides

5.  Age

6.  Family history of circulation problems

Most people with carotid artery narrowing do not know they have it.  If you have had a heart attack or has peripheral vascular disease, then you have a higher risk for carotid artery narrowing.  Most patients with carotid artery stenosis do not need surgery.  Age and family history you are stuck with!  Our goal is to prevent the narrowing becoming worse but making sure that your blood pressure, blood sugars, and cholesterol levels are well controlled, and that you stop smoking.

If you have been diagnosed as having carotid artery narrowing, the prognosis is really quite good.  Most people will never need their carotid artery repaired.  Th old standard for treatment of carotid artery narrowing that was 60% or greater was surgical intervention based on a study published in the New England Journal of Medicine.  However, this study was prior to the current era where we have Plavix which is like a super aspirin, and statin drugs.  Therefore, the management of carotid artery disease has changed somewhat to a more conservative approach, as outlined by the writings of Dr. Frank Veith, one of the most thoughtful and smart vascular surgeons who has been around a long time and seen  it all.  I personally discuss surgery in patients who have had a TIA or ministroke and carotid artery narrowing on the side of the TIA.  A TIA is a stroke like symptom, but by definition, you recover function within 24 hours.  If you have a TIA, and have severe carotid artery narrowing on the side that caused the TIA, then you have a high risk for a full blown stroke, and really should have intervention for the carotid artery narrowing.

In terms of treatment for carotid artery stenosis, as I mentioned most people do not need intervention, and can be managed with anti-platelet agents that thin out the blood such as aspirin or Plavix, as well as control of their cardiovascular risk factors, statin drugs as necessary, and smoking cessation.  Why not fix all carotid artery narrowing when it’s present?  Because the intervention itself carries a risk for stroke and even heart problems.  This business is all about balancing the risks versus benefits of everything we do.  If the risk of stroke is low with carotid artery narrowing, then it is better managed conservatively.  If intervention is required, the options are to either have a surgical intervention or a carotid artery stent.  There are advantages and disadvantages of both. I personally do not do carotid artery stenting; I think that is better left to someone who has experience in doing the procedure, but also in fixing problems that may arise both during and after the procedure.  If I think a patient is better served by a carotid artery stent rather than surgery, I will ask them to see a friend of mine who is a neurointerventional radiologist, basically a specialist in all things related to the blood flow to the brain.  He might come back and tell me “no, I think this case would be better served by surgery, or yes I think carotid artery stenting would be a good option.”  Remember the old adage “if your only tool is a hammer, the whole world looks like a nail.”

 

High Intensity Intervals For Old People Like Me Part II

Monday was my leg day, and after testing the out limits of my quadriceps weight bearing abilities, the last thing I wanted to do was to get on the stair stepper or treadmill and run.  So I experimented with the incline and speed on the treadmill.  I took my baseline heart both with a stop watch and the machine and it correlated well at around 68 beats per minutes (bpm).  Then I started off at 3 degrees incline and at 2.5 miles per hour (mph) on the treadmill.  With each change in the variables, I correlated the machine readout of my heart rate with my stopwatch, and they were actually quite comparable.  I increased my incline sequentially by a few degrees, and increased my walking rate to 3 mph.  at 15 degrees incline and 3 mph, my heart rate was persistently in the 130+ range.  At 10 degrees, it was in the 120 range.  So I varied the incline every 2-3 minutes, and kept the speed at a comfortable constant 3 mph for 40 minutes.  At the end, my legs did not hurt, and I had a good cardio workout.  It also did not seem as onerous as pushing myself hard on the treadmill or stair stepper for 30 minutes, and I achieved the same calculated calorie goal.  For those who say that they don’t have 40 minutes to do this type of experiment, you can split it up into 2 20 minute sessions, one in the morning and the second at night.  In fact, there is research that suggests splitting up cardio into 2 shorter sessions rather than 1 long session boosts your metabolic rate higher than just one session.

Principles of Life

I looked through my old notes that I had taken on my laptop this morning, as I thought about what I was grateful for.  I try and start out the day by spending a few minutes being grateful, it really does change something inside me, no matter how I feel when the alarm rings at 5 am.  I found some old notes that I forgot I had made.  Instead of writing something about medicine, I have copied them down here.  My apologies if they are plagiarized from someone, I don’t know what I was reading or thinking or even when exactly I made these notes, but they are just listed below

THE FOUR OVER-RIDING PRINCIPLES TO LIFE

  1. There is only one important time, and that time is NOW. The present moment is the only time over which we have dominion
  2. The most important person is always the person you are with, who is right there before you (including yourself if you are alone), for who knows if you will have dealings with any other person in the future
  3. The most important pursuit is making the person standing at your side happy, for that alone is the meaning of life
  4. In whatever situation you are in, whether good or bad, have fun and be happy. That is a conscious decision we all make, for in between any stimulus and response there is an infinite time period; it is up to us and us alone to decide that response

When To Consider An Aggressive Treatment for Venous Reflux and Varicose Veins

A young lady who saw my previous article of compression hose asked me to discuss the topic of when to treat vein issues more aggressively.  To recap, venous reflux that can lead to varicose veins, pain, swelling and and a generalized uncomfortable sensation in the legs, particularly in the calf area.  Sometimes, so called restless legs syndrome may be due to venous reflux.  The goal of management is to move the vein blood out of your legs.   Conservative management includes an exercising program, anything that uses the calf muscles like walking 20-30 minutes a day, which promotes movement of the vein blood back up the legs.  Remember, venous reflux leads to vein blood sitting in your legs veins, and there is no medications currently FDA approved to treat these symptoms except for pain medications (although there are some herbal and European products that have been reported as helping).  In addition, prop your legs up, be careful about your weight (the more weight you carry the harder your veins have to work), and wear compression hose.  If that does not help with your symptoms, then consider an aggressive approach to the problem

The vein system is made of the Deep Veins, and the Superficial Veins.  There are also connections between the two called Perforator Veins.  There are one way valves in both the deep and superficial venous systems, that normally allow blood to go up the vein. These valves snap shut and prevent the backward flow of vein blood, particularly when you sit or stand.  By the way, leg vein valve issues are completely unrelated to heart valve issues.  As gravity tries to pull the blood back down, if the valves are not competent, then blood tends to accumulate in the leg veins. In time, the veins tend to swell and lose their structural integrity.  Veins have an elastic component to them, and as they overstretch, the elastic component is damaged, and they act more like plastic bags, rather than elastic structures. This leads to varicose veins and many of the symptoms  associated with venous reflux.

A venous Doppler test is performed to make sure there are no issues with the deep vein valves or evidence for previous blood clots.  In addition, the superficial system is assessed to check the competency of the superficial valves, and to measure the size of the vein both when lying down and when standing.  Most people with varicose veins have problems with their superficial venous system, which includes the Greater Saphenous Vein (GSV) which runs from the groin down to the ankle on the inside part of the leg, and the Lesser Saphenous Vein (LSV) that runs from behind the knee to the outer ankle.

For patient who doe not get relief of their symptoms with conservative management, we will discuss a more aggressive approach with why we call ablation of the saphenous vein.  Essentially, the goal of the ablation procedure is to shut down the GSV or LSV.  People usually ask me at this point, “don’t I need this vein?”  The answer is yes, normally you do need that vein, but right now it is hurting you rather than helping you.  The blood in the faulty vein is flowing backwards down the leg rather than up towards the body, and thats why you get the symptoms of pain, swelling an varicose veins.  Their are essentially 2 technologies that are currently popular for ablating the GSV or LSV, but there are others being developed.  The first technology is radio frequency ablation (RF), and the second is laser ablation (EVLT).  I prefer the RF but they essentially both do the same thing, which is damage the inner lining of the vein and shut down the backward flow of vein blood.  The procedure takes about 30-45 minutes to do in the physicians office using local anesthesia, and either oral sedation or I.V. sedation. The inside of the vein has no sensation, its the outside surrounding tissue that has pain fibers.  We used whats called tumescence anesthesia where we infiltrate dilute numbing medication all around the vein under ultrasound guidance.  If this is done properly and with some patience, the procedure itself should not be painful.  If you have pain during the procedure, its because the numbing was not done completely.  Most people return to work within a could of days after the procedure, because the recovery is so much better than we used to see when we stripped veins.  There are other techniques that are being developed with injection of whats known as a sclerosing agent into the vein to close the fault vein down, but we can talk about that at another session if anyone is interested, because RF and EVLT dominate the current treatment market.

So the question becomes, do I need to have the aggressive approach with ablation of the vein done?  It really depends on the severity of your symptoms, and how much your veins and leg swelling are bothering you.  Its not like an artery problems like coronary artery disease where you might have a heart attack if you are not treated for chest pain.  Vein issues are more of a lifestyle problem.  “How much are my veins and swelling bothering me, and am I ready to have a more aggressive vein treatment?”  Some patients will have huge varicose veins, but they have mild symptoms and prefer to just leave the vein issues alone; that is a perfectly reasonable approach.  Other patients will have a lot of symptoms of pain and swelling, and will want to have the ablation procedure for relief of their symptoms.  In general, insurance companies will cover the ablation procedure if you have worn grade 20-30 mmHg compression hose for over 3 months, and have significant symptoms that limit your work or lifestyle such as performing your normal activities of daily living or exercising.  Some insurances (especially Cigna) can have a rider on your policy that does not allow ablation procedures no matter what.

There are certain circumstances I do recommend strongly that patients have an ablation procedure performed.  If you have a venous stasis ulcer, either healed or open, then an ablation procedure really works well to close the ulcer.  You can look up venous stasis ulcers on the internet, but these are painful sores that form on the inside or outside ankle and take a long time to heal.  The ablation  procedure performed properly and for the right reason not only helps to close the ulcer, but also reduces the risk for recurrent ulcers.  Once you have a venous stasis ulcer, the risk for recurrent ulcers is about 50%.  If you have the ablation procedure performed, the risk for recurrent ulcers falls to 9%.  I had a patient with a 20 year history of a venous stasis ulcer on his right ankle who healed his wound within 4 weeks after the ablation. Interesting side note, he had Cigna insurance, and despite the fact that we had pre-approval for the procedure, after the ablation Cigna refused to pay because they said it was not in his policy or some other BS like that, so I ate the cost of the RF ablation kit which is about $625.  Oh well, at least his wound finally healed up.

Other situation where I recommend strongly that you have an ablation procedure is if you have had bleeding from varicose veins.  If anyone has experience this event, it is very scary for patients.  It looks like you cut an artery because blood comes out at high pressure due to the venous reflux.  It is a painless event, and usually leads to a picture of blood all over the place (hog slaughter is how one patient described it…well we live in Texas).  Its actually simple to control if this ever happens to you.  Just wrap the bleeding area with compressive dressings snugly, get your butt on the ground and your feet propped up on the wall, and don’t unwrap anything for 30 minutes.  When you get your legs up straight, the vein blood drains back into the body and reduces the vein pressure in the bleeding vein.  Ablation needs to be performed for bleeding veins to prevent further bleeding.  What we usually do it inject the offending vein with clerking agent to scar it up and clot it, and then set the patient up for the ablation procedure as soon as possible.

Other situations when I recommend ablation is for patients who have a lot of venous stasis changes (brown discoloration of the skin), or repeated bouts of cellulitis.  Essentially, the reason some patients get this problem is that with venous reflux, the skin becomes permanently damaged due to the chronic high vein pressures.  This can lead to a permanent staining of the skin (venous stasis discoloration) as well as possibly recurrent skin infections (cellulitis).  I think I will address this issues at a later session.  Time to go to work

The Alchemist

I like to read books.  I don’t read novels, but like books that make me think.  I recently read a quote that was in the Farnam Street Blog that got me re-reading The Alchemist by Paulo Cuelho, a book that I have read at least 8 times over the past 2 years.  Before I talk about the book, I do highly recommend that you at least take a look at the Farnam Street Blog.  It is an intelligent summary of books and articles that challenge thinking.  The quote was from Joseph Tussman, who was a Professor of Philosophy at Cal Berkeley.  It states “What the pupil must learn,  if he learns anything at all, is that the world will do most of the work for you, provided you cooperate with it by identifying how it really works and aligning with those realities.  If we do not let the world teach us, it teaches us a lesson.”

I first read the Alchemist at the recommendation of a new friend Peter Stickney.  I found out we share a lot of interests, and we have become really good friends.  The first time I read the Alchemist, I initially thought I was reading a simplistic children’s book.  But as I kept reading it, I started to reflect more on some of the message that seemed to spring up to me from someone in my submerged sub-conscious.  Every time I re-read the book, I get something new out of it.  Its one of those things, kind of like watching The Shawshank Redemption that you never get tired of seeing it over and over again.  Here is the link to that Farnam Street Blog page