Lasix or Aldactone with no kidneys?

My mother had a heart/kidney transplant in 2010. Her new kidney eventually failed and because of very high blood pressures, they removed it all together. She does dialysis at home 5 nights a week. She was on aldactone and lasix, was taken off the aldactone but has never been taken off the lasix. She does have problems with her heart, such as fluid around her heart, arrhythmias and enlargement and sometimes gets wet lungs, but from what I understand from reading about diuretics, diuretics only work when you have function in your kidneys, and obviously she has no function if she has no kidneys. I don’t find her doctor here in this little town is a good doctor. Is it wrong for her to be on Lasix with no kidneys? She is 65 and is also dealing with cancer. I would appreciate any input. Thanks.

A very good question …

Frusemide (Lasix) is a diuretic, but also has a venodilator action … this is why it works so quickly as a treatment for acute pulmonary oedema in the ER where it has a more immediate venodilator role and only later prompts a diuresis.

So … OK … what is a venodilator? A venodilator is a drug that acts on the central veins to dilate (relax) them and this allows them, in simple terms, to hold more blood … the other major group of venodilator drugs are the nitrates - like GTN, or the longer acting ones like isosorbide mononitrate (Imdur, Monodur), isosorbide dinitrate (Isordil) etc. while some of the newer agents like nicorandil (Ikorel) etc do too.

Using any one of these (and frusemide has a similar action IN ADDITION to its’ diuretic action) relaxes the great veins - in particular, the superior and inferior venacava - and reduce what is called ‘pre-load’.

Pre-load is the waterfall of blood returning to the heart through the venous system and, by relaxing the great veins, allowing ‘pooling’ of blood in the venous system, and reducing the inflow to the right side of the heart, the heart has a better chance of pumping out a flooding set of lungs, improving oxygenation (and thus improving heart function further) and thereby getting on top of an episode of acute left ventricular failure.

Frusemide thus does have an effect that (short term) benefits the heart outside and beyond its’ simple diuretic function.

That said, the use of frusemide for this purpose is almost only valuable in acute left heart failure and pulmonary oedema - the other longer acting nitrates, etc. are better as longer term treatments rather than using frusemide … for THIS particular effect. More usually, frusemide is, as you rightly point out, a diuretic and, in an anephric (no kidneys) situation, frusemide is of no use at all for its diuretic function and although it will continue to have a modest venodilatory effect, this is better provided by other agents.

So … in an anephric patient (your mum), there is little (or nothing) to be gained by using frusemide.

In dialysis patients WITH residual renal function and a urine output, there is something to be said for ongoing frusemide therapy to try to improve (if possible) the urine output - while there IS a urine output. The more urine a dialysis patient can muster and pass, the less severe needs to be any fluid restriction. So, if frusemide is helping to sustain a urine volume, then there is some point in pushing on with it. But even then, industrial doses are usually required to produce any meaningful response from kidneys that have failed to the point where dialysis is needed. This then introduces a weighing up of the potential benefits of frusemide (which become vanishingly small) versus any side effects (skin bullae … like blisters … or hearing risk) that might accrue from industrial strength doses of frusemide.

So … to answer your question: is it wrong for her to be on Lasix with no kidneys?
… there is likely little point at all in its’ use. “Wrong”? … well, not quite as it will be exerting a small venodilatory effect of some possible value - though other drugs are much better at that than frusemide. “Pointless” is maybe a better descriptor as there is no place for its’ use as a diuretic in an anephric situation.

Her volume problems are far better managed by

(1) lowering her post dialysis weight to an appropriate dry weight (which, from your description, she seems far in excess of … she has fluid round her heart and wet lungs)

(2) taking off more fluid

(3) limiting her fluid intake until she has reached dry weight … and this is best and most easily done by removing as much salt from her diet as possible

(4) managing her dialysis volume balance much better then it sounds as if it has been. On 5 nights per week HD at home, it is a little disturbing that she is as overloaded as she sounds she is, and that she is having such trouble.

An echocardiogram might be a good step to assess her cardiac function and to exclude significant pulmonary hypertension.