I’ve only been doing this since the end of February, but, in my opinion, on short daily, the biggest risk on a daily basis is a significant air embolism. Proper attention to setup and to connecting the lines should prevent it though, unless there’s a serious machine malfunction. I don’t know how it works on the NxStage, but on my more conventional baby K Fresenius, the air detector and clamp on the veinous bloodline is the last thing on the machine before the blood comes back to me. It would detect any air bubbles that managed to get past the two air chambers and clamp down instantly. There are many safeguards on the machine before this would happen without an alarm stopping the machine though (and the metal clamp on the veinous bloodline closing). I’m sure there must be something equivalent on every dialysis machine. On a daily basis, the biggest risk for an embolism would be from something I might do, like an improper connection of the veinous bloodline with the veinous needle line, or having a lot of air in the veinous bloodline before even starting treatment (it’s just a matter of checking it, really). Because of that, I’m extremely careful about this. Whereas air on the arterial side would have to go through the whole blood circuit, any air that’s in the veinous line will go directly into me, so, I check the whole veinous bloodline very carefully before I even connect. When connecting it to the veinous needle line, I find that it’s sometimes virtually impossible not to end up with some very tiny air bubbles at the connection after the connection is made - even with the utmost care in squeezing both tubes so that saline come directly into contact with blood. This doesn’t seem to have been a problem so far. During training, I forgot to close the clamp on veinous bloodline at the end of priming/recirculation once, and as I was connecting the bloodline to the needle line, my nurse stopped me to show me that there veinous bloodline was full of air. So, I felt stupid for the rest of that day, but I learned my lesson. I know the symptoms of an air embolism, and I’ve been taught to lie on my left side with my head down and my feet elevated if I suspect one, and call the paramedics. Lying like this prevents the air from getting to the brain or the lungs.
I guess hemolyzed blood would be the next thing. There are many safeguards against this, and all would have to fail, but it could happen, just as it could in a dialysis centre. The machine would alarm and stop if either the conductivity or the dialysate temperature were to go beyond the established limits, but, I keep an eye on them to spot any trend ahead of time. It would also stop if there were a kink in the lines somewhere. So, as far as hemolysis goes, you just have to trust the machine and know how to recognize it by appearance in the veinous line. You also have to be careful about checking the quality of the water supply post carbon filter before each treatment (for chloramine, in my case, from the city water), but I gather that doesn’t apply to the NxStage.
A blood leak in the dialyzer would stop the machine, but my biggest fear, really, would be one of my needles coming out when I’m sleeping. I’m fully awake and aware when doing 2 hours short daily, so, even if it happened, I would simply do the same thing I did when it happened to me in the dialysis centre twice: put my finger on the hole! If it happened while on nocturnal, it could be a problem though. I have a detector on my veinous needle for that, but, I would have to be sure I woke up. This is why I was taught to use a large Tegaderm to tape my needles. It’s taped at the needle with the Tegaderm, and the needle line is again taped at my wrist, over a burn net. It seems pretty secure. At the dialysis centre, they only use paper tape at the needle, in case they have to reposition the needle a bit after treatment has started. I don’t have that concern since I use the buttonhole technique and dull needles. As long as the needle is in, it’s in the same place as it always is, so, it’s predictable.
I was on hemo for 2 and half years in centre before switching to home hemo. The only difference between now and then is that now, I’m the one who has to be aware of the risks, rather than a nurse.
Pierre