Dear Jeff
Before the era of dialysis, and kidney failure progressed through a chain of symptoms to inevitable death, a symptom complex (or group of symptoms) commonly described the journey that patients took. It may have been some these that your doctor described. Nowadays, however, with dialysis (or pre-emptive transplantation) as the usual course for most people, we commonly do not like to see a patient becoming particularly unwell or sick as a result of their kidney failure but, rather, we begin dialysis, whether haemodialysis or peritoneal dialysis, before any major or significant symptoms of illness occur.
For most people, this means starting dialysis somewhere around a GFR of 8 to 10 ml/min. We know that at this low level of GFR, more significant symptoms are just around the corner. In addition, biochemical and fluid changes begin to exert ever increasing stresses on the body at low levels of GFR and it is best to try and avoid some of these problems if possible.
There is a study currently being conducted in Australia (indeed has just concluded and its results are soon to be released) called the IDEAL trial. This stands for Initiation of Dialysis EArly or Late. This trial was conducted exactly for the reason that we still do not know whether haemodialysis (and it was a hameodialysis trial) should start earlier or later. Provided they were still well in themselves, half the patients in this trial (intentionally) started dialysis with a GFR between 5 - 8 (= Late). The other half started their dialysis (intentionally) at a GFR of 10 to 12 (= Early). Which is best? Hopefully the trial will help us find out. It is a question that has never really been answered until (hopefully) now.
Particularly for haemodialysis, good, early preparation – and by this I mean not only full (and all) modality choice discussion, education and demonstration but, most importantly of all, AVF creation – is absolutely essential. An AVF needs to be created some months prior to its intended use and should be put in, when haemodialysis is anticipated as the chosen modality, when the eGFR dips below 20. It doesn’t matter if it sits there, for months or even a year or two, unused. It does no harm – at least of any significance – and it has plenty of time to mature so that it is ready to use when needed.
Admittedly,for some patients, if kidney failure is sudden, acute, or unexpected, there may be little or no time to prepare for dialysis. Others, like the ostrich, prefer to keep their head buried deep in the sand and ignore or resist their impending renal replacement therapy. For these patients, one does the best one can with what one has. It often means an unhappy start to dialysis or, certainly, an ill-prepared one, and usually results in catheter access as a last resort. THis is always the lesser choice. Most patients, however, have a predicted and slower course to end-stage kidney failure and full preparation (and decision-making) is therefore possible.
For PD, there clearly is not the same preparation lead-time. A Tenckhoff catheter can be inserted when the time is right, and dialysis begun nearly straight away. We tend to like to put our TC’s in a couple of weeks before we use them to ensure that the catheter ‘beds in’ and the risk of leakage is minimised but, essentially, it is " insert and go".
One thing that I find people do not really well understand is the lack of symptoms. If you have something wrong with your heart, you will likely go to your doctor complaining of pains in the chest, shortness of breath, palpitations or some other feature that draws attention to the heart as the likely cause. If there is something wrong with the lungs, there is cough, breathlessness, the production of sputum – or some other symptoms that alerts both the patient and doctor to the presence of lung disease.
But … if the kidneys fail, nothing much happens.
People may complain of tiredness or lassitude, perhaps easy fatigability – but so do I, commonly, and especially after the staying up late at night to write these responses! These are symptoms that we all complain of from time to time and they hardly draw our attention or the attention of doctors to advancing and near end-stage kidney disease. Pain is uncommon with kidney disease. Itch and night-time cramps or loss of appetite, taste appreciation and the enjoyment of food may occur, but these are often ascribed to other causes – and things like cramp occur in normal people too. Most of the symptoms of kidney failure, prior to the need for dialysis, are those of the associated anaemia. Not much happens on the kidney side.
It can therefore be a surprise and shock to be told that dialysis is imminent. How could that be? I feel fine! There’s nothing wrong with me that a holiday won’t fix. Certainly, not major organ failure! That’s why kidney failure is often called the silent disease or the silent killer. Most people don’t know they have it until it is upon them.
I describe it this way to my patients …
Imagine you are blindfolded. You are walking, ever closer to a cliff. You do not know the cliff is there – but it is. You have little warning and there is nothing to alert you, perhaps apart from a slight breeze in your face. The going is easy. Nothing much is happening. It seems an easy walk … … … until that last step hurtles you over the edge. If that happens, we have to call the SES (State Emergency Service) to haul you back up again with stretchers and guerneys and a helicopter hovering offshore. In other words, a bit of a business!
The art – and there is art left in medicine – is to permit you to get reasonably close to the edge of the cliff but not to allow you to fall off.
There is no need to start dialysis back when you are ‘miles from the edge of that cliff’ – ie: when your eGFR is 50, or 40, or 20, or even (in many) until the eGFR has dropped below 10. You will still be on " flat ground" but by an eGFR of 10(ish), you are indeed getting uncomfortably close to the edge of that cliff. It’s time to turn you around. You’ve managed under your own steam until now but now it is time to intervene. We know from experience that most people begin to risk more significant ill health and/or significant other organs stress (which could be avoided) if the eGFR is allowed to drift too far down.
Here, a word about eGFR. It is not the be all and end all measurement that some think it to be. It’s a fluffy number. It is not all that accurate – though we would like to think it is – and should not be used as the sole determinant of a patient’s progress. It is one measure, but not the only measure.
Having said that, young people (especially) can often tolerate their end stage renal failure symptoms (or lack of them) to eGFR’s of 5 to 8 before really beginning to feel the pinch. I tend to use a combination of numbers – eGFR, creatinine, phosphate, calcium, degree of anaemia, BP control, symptoms of breathing and fluid retention, appetite and weight change (up or down) … a range of things … in combination with a simple " how are you feeling?"
OK, I hear you say that ‘there is little science in that’, but that’s when judgement comes to bear.
So, no, it’s not just numbers. Its numbers, a sense that the patient is beginning to struggle a little, perhaps some symptoms – though relatively mild still – and that old-fashioned non-scientific sense that ‘now is the time’. Experience helps as well.
Finally, either the basic disease or any associated co-morbidities (other things wrong beyond the kidney disease) often play a role. For example, I tend to put diabetics ‘on’ a little earlier than I would somebody with single organ kidney disease and no other problems. People with heart trouble will commonly struggle when the eGFR diminishes down below 10 or 12 (and occasionally even earlier in the course of their renal impairment). They may need earlier dialysis than others. As I continually say at this site, every patient is an individual. Every patient must be assessed on their merits as an individual. What can be left for a while in some, cannot be in others.
I don’t know whether that’s helped you.
John Agar