Over the last ten days I have had high Venus pressures and pain in the Venus portion of my fistula while dialyzing, and pain in my fistula after completing dialysis. Some days the pain would subside and my Venus pressures were lower, although still elevated. When I ran last Friday I had a higher level of pain than I had before, and pain in my fistula after I finished running.

I called the vascular care office and they were able to get me in this morning (Monday). After using a scope on my fistula the doctor told me there was some narrowing in my fistula, and that scar tissue was also contributing to my problems. He said the scar tissue was causing the pain I was having during dialysis.

I questioned how I was getting scar tissue in my fistula. He replied that when you run at pump speed 500, the blood sprays out of the two openings in the fistula a needle, and this hard spray inside your fistula can cause scar tissue. I have been running on this fistula for over five years and this is the first time I have had an issue with scar tissue.

I asked the doctor how the scar tissue can be dealt with, then I got the bad news, nothing can be done to repair damaged scar tissue. He advised dialyzing at a lower pump speed to lower the chances of causing more scar tissue and to protect my fistula from further damage.

The doctor performed an angioplasty, he made a small incision just below and to the right of my arterial button-hole, and used a balloon-shaped catheter to enlarge the Venus portion of my fistula. Since the surgery, my Venus pressure has been reduced while dialyzing this evening, and my pain during dialysis is gone.

My dialysis center has always advised using the highest pump speed possible, for me that was 500. The arterial doctor advised me to use a lower pump speed as long as I was getting adequate clearance. He advised using a pump speed of 350-400. I’m not sure that I can put up with the increased run time using this slow of run speed. When I started tonight, I set the pump speed at 400, and my total run time to remove 1.6L would have been 2 hours and 50 minutes. My normal run time were less than 2 hours and 15 minutes.

I plan to start reducing my run speed, but am cautious to reduce it from 500 to 400 without ensuring that I will continue to get adequate clearance at the lower pump speed. My plan is to use the lower pump speed of 400 the day I draw blood for my monthly labs, so I can find out what the reduced pump speed does to my clearance, before making the final decision on what run speed I will be using.

My next blood draw will be in another in two and a half weeks, in the mean time I plan to use a maximum pump speed of 450. I’ll post a follow-up blog entry to advise how this works for me, and how the lower pump speed affected my clearance value.

02/18/16 Update – I have been running with a pump speed of 450, and it has added about ten more minutes to my run time and my clearenace stayed the same.  My concern with reduced clearenace at the lower pump speed was unfounded.  The NxStage System One is automatically calculating your run time based on Dialysate Rate.  Dialysate Rate is based on a combination of UF Goal (amount of liquid to be removed) and pump speed.  When I run at a lower pump speed, the total time to remove the liquid actually stays the same, but the length of time to use all the Dialysate lenghthens by about 10 minutes.  The great new is that on a NxStage you can lower the pump speed and never affect your clearenace, the NxStage System One is always providing the same amount of cleareance by lengthening the run time.  The reason cleareance would be an issue based on lower run speed is only when you are dialyzing in-center, you are limited to a specific amount of time so they can the next dialysuis patient on and started.