I am presently providing life-saving hemodialysis treatments to my wife 4 1/2 hours a day, four times a week. Dialysate preparation is done two other days per week. Each treatment consists of a prep time (20 min), patient on (20 min), treatment (3.25 hours), patient off (15 min), teardown (10 min) and equipment sanitation (10 min).
In order to perform these relatively complex medical treatments, one must receive several weeks of full-time training in both operational and emergency procedures, pass both a written and an oral exam and do an internship. I had to take time off work for training and I receive no compensation for performing these treatments.
We are required to do the treatments with no more than a one day gap in between. I am obligated to be on duty, remain on the premises, and do the treatments during normal daytime hours because small mistakes, while less than fully alert, can have grave consequences. Here are some of the medical risks with hemodialysis:
- Air embolisms. This can happen if an air bubble gets trapped in a blood line during treatment preparation and the bubble is allowed to enter the patient’s body which can lead to a fatal stroke.
- Dehydration. This can occur if too much fluid is removed because the machine is malfunctioning or incorrectly programmed which causes intradialytic hypotension with low blood pressure, a high pulse rate, fainting, muscular cramps and, in extreme cases, heart failure.
- Exsanguinations. This can occur if one of the blood lines between the patient and machine comes loose allowing blood to escape while the machine is pumping at the normal treatment rate of 400 ml/min. The rapid blood loss can lead to life-threatening hypovolemic shock and heart failure.
- Hemolysis. This can happen if a blood line becomes pinched, a clot forms in the blood circuit restricting flow or, when the dialyser membrane ruptures allowing dialysate to enter the bloodstream. When blood pressures increase to the point that blood cells rupture or when dialysate contamination occurs, hemolytic anemia will result eventually leading to cardiac arrest or stroke.
- Stagnant hypoxia. This can happen because of sudden equipment failure or power outages. If the 300 ml’s of blood outside the patient’s body is not returned within 5 minutes those blood cells will die of oxygen deprivation.
- Septic infections. If proper antiseptic procedures are not followed to the letter, serious systemic infections can occur which leads to high fever, chills, a rapid pulse and hospitalization. Hemodialysis treatments, by their very nature, bypass all normal body defenses.
The emergency procedures to deal with these issues must be carried out quickly and calmly by someone properly trained to do them, such as myself.
If you are curious what equipment we use for home hemodialysis, here is a rundown. Hemodialysis machines are complex beasts as shown in this humorous greeting card:
The photo below shows a typical hemodialysis machine (and, yes, they are huge and weight more than 50 Kg or 110 lbs). The Heparin pump (unlabeled) is between the two peristaltic pumps. The IV pole has four hooks (cut off in the photo). We use all four hooks when using premixed dialysate bags but normally we mix our own dialysate with the help of a diafiltration machine (see below). We use ~30 liters of dialysate per treatment.
A critical part of any dialysis setup is a large supply of sterile water. Our diafiltration machine prepares 60+ liters of dialysate twice a week from treated tap water (with <5 ppb TOC toxicity). The machine contains multiple micron filters, a sediment filter, an ultraviolet irradiation system and a cascade of reverse osmosis filters. I do additional chemical strip testing to verify that the water is sterile on every batch. I also send water samples to a lab for microbe analysis every few months. The filtration modules are replaced every 12 weeks or more often when the water quality decreases, esp. after a series of storms or wildfires.
This ultra-pure water is then mixed with a sterile acid, a bicarbonate and a number of electrolytes (potassium, lactose, sodium, etc.) to produce exactly the right dialysate composition and conductivity specific to the patient's prescription. Fortunately, I don't have to mix everything from scratch as we are supplied with a prescription concentrate. The dialysate is maintained at body temperature to keep the patient from becoming uncomfortably chilled during treatment. The batch must be used within a few days to avoid microbe contamination.
When traveling abroad or on a cruise, bringing both the hemodialysis and diafiltration machines with us is impractical. Whenever possible, dialysis centers are used which requires months of planning and additional blood tests. When dialysis centers are not an option, we take our hemodialysis machine with us in a custom, padded, trade-show-style transport case which is difficult to get onto airlines as carry on. In place of the diafiltration machine, we arrange for our medical provider to cargo ship up to 15 boxes of premixed dialysate to the destination or docks along with several dialyzers and associated sterile tubing just prior to the trip. This takes 2+ months of planning. One week of shipped medical supplies generally weighs around 150 Kg or 300 lbs and fills most of a room closet. The premixed dialysate, in 5-liter bags, are hung on an IV pole for each treatment. The gravity fed dialysate flows through an infusion warmer attached to the side of the dialysis machine to bring the fluid up to body temperature.
Once a month, I do multiple before and after blood draws and specimen labeling. Depending on the type of blood analysis required, my lab work includes blood fractionation (where the plasma, leukocytes and erythrocytes are separated). This is done with the help of a medical centrifuge. (The blood specimens are always counter-balanced with specimen tubes containing an equal amount of water placed in opposing holders.)
Some specimens are refrigerated and some are not. These are then delivered to a lab within 24 hours. The lab results always include a Kt/V assessment based on the difference between the before and after fractionalized blood samples. Kt/V measures the adequacy of urea and fluid removal. The dialysis treatment duration is sometimes adjusted as a result.
Right now, the treatment time is around 3 1/2 hours (not including setup and termination) 4 times a week but the duration also varies with the amount of fluid being removed and/or interruptions due to alarms. The fluid takeoff is determined by comparing the patient's actual weight against their "dry" weight prior to each treatment. Removing too much fluid causes cramping and hypotension which is counteracted by given the patient an intravenous "bolus" of 0.9% saline solution.
I use 7 different sizes of syringes from big 60ml ones for air removal to tiny 1ml ones for Epoetin Alfa [a.k.a. Epogen, Procrit, Amgen] intravenous injections (at ~$500 per injection) and 5 different types of cannulation needles depending on the type of cannulation and whether the needle is being inserted into a vein or artery.
Cannulation is the trickiest part of the dialysis procedure as it is not easy getting both 15 gauge needles properly inserted into the vein or artery with good blood flow. One can miss altogether or partially miss or cause an "infiltration" where the needle passes through the blood vessel and out the other side. This results in a painful hematoma with swelling and discoloration that needs immediate attention with ice packs. I have seen hospital nurses do infiltrations on two occasions. A less common danger is a "blow out" where the blood vessel is so weakened from numerous venipunctures that the blood vessel no longer stays together causing a serious hematoma. I have not caused a "blow out" thus far. In addition to the items already mentioned, there are blood lines, sterile pads, tape, antibiotic creams, examination gloves, masks, forceps, blood pressure cuffs, thermometers, breakers, sharps containers, lab coats and other items too numerous to mention.
All our medical equipment is powered from a 1500 VA, true-sinewave, double-conversion UPS approved for medical use, providing super clean AC from line power, batteries or gasoline generator (during power outages).