My friend Max often says to me, “You should write about dry weight. It’s a great way to track your dialysis and your health.” I used to think that it was a bit more complex than that, but over the last month or so I have come around.
Dry weight is the weight you should be if you had normal kidneys and you just had your morning pee. So in dialysis, it’s the weight you aim to be just after you come off the machine.
When you first hook up to the machine, you will often be carrying extra fluid, which makes your heart work harder and drives up your blood pressure (BP). The more fluid, the higher the BP. The more damage you are doing to your heart.
During the run, the machine not only cleans your blood, it also removes the extra fluid (the amount it takes off is usually agreed between you and your nurse) When you come off the machine, if you are at your correct dry weight, and are otherwise healthy, you will also have good BP (somewhere near 120/70).
It’s a pretty simple equation.
But sometimes it takes a while to sink in, especially if you are concentrating on something else. I had a virus over the last month. I couldn’t exercise and unconsciously ate less. After just a few days, my BP was very high at the start of the run and it stayed high. I was convinced that it was the virus working some BP mischief. I was sure my dry weight hadn’t changed. But when I finally shook off the virus, my BP was still too high. I discussed this with Chris (Unit Manager) and as an experiment, took my base weight down a kilo (from 78kg to77kg). My BP went down, though not to my 120/70 ideal. The next day, I moved my base weight down another .5kg to 76.5kg. Success! My dry weight BP was 121/70. I had lost 1.5 kg during the month and I had masked the loss by drinking more and not taking enough off.
It all seems pretty obvious now: right dry weight = right blood pressure. I was convinced it wasn’t that simple, but it was.
From now on, I will do like Max does: quietly monitor my BP and dry weight over each run. Keep an open mind. If my BP is high, I’ll, experiment with a lower dry weight. If my BP is low, I’ll add a .5kg; I may have gained dry weight.
Dry weight is of course not the only answer to a healthy blood pressure and a healthy heart. But it is often the answer, it’s simple to monitor and it’s DIY: no doctors needed.
What’s your dry weight (this week)?