Update on 'Mysterious Hypotension'

I received an email from Dr. Agar regarding his unofficial speculations about the cause of my low blood pressure. I just wanted to share the response here since it pretty much summarizes the situation. The only thing I didn’t really detail is the depth of the abysses I have been to these last couple of months. The way I have been feeling has prompted me to actually get my affairs in order, beginning with making sure Andy has all the information he will need as far as insurance, paperwork, internet passwords, etc, and a rough draft of my living will. It has really been bad.

Dear Dr. Agar -

I’m so sorry I have not updated you before now; things got much worse before they started getting any better and I still haven’t quite stabilized. I’ve spent several months unable to do even the most basic tasks, so I do hope you will forgive the delay.

My doctor ordered the new (3.0 CA) bath in May and I had my first treatment with it on May 9th. However, I only had two treatments of the 3.0 before leaving for New Jersey on vacation and the center where I dialyzed only had the 2.5 CA bath. At that point my BP was in the 70/40 range - where it had been for about six weeks - and it only got worse. After returning home I resumed the 3.0 bath but my BP kept dropping until finally one evening I lost consciousness immediately after going on the machine. When I regained consciousness my BP was 57/33. That was May 26th.

By the middle of June - three weeks on the 3.0 bath - my BP was up to 110/70 - a tad lower than my normal, but normal. Normal! My serum calcium at that point was 10.7 and my phosphorus and PTH were 2.2 and 45, respectively. By the end of June my calcium was 10.2 and my BP had dropped back down to the 90/50 range.

At this point I had rounds with my doctor. She insisted that I continue with the Midodrine, even though it had had no effect and I’d been on it for two months with no liver enzyme tests. She also wanted to start me on Flourinef (sp?). She had prescribed it two months earlier but told me not to take it until my cortisol levels came back. This time she denied ever saying that and told me to take it with the Midodrine.

I went home and thought about it and came up with the following conclusion: if I wanted to discover the root cause of the problem I couldn’t throw three different solutions at it at one time, because if the problem resolved there would be no way of knowing which had been the solution. My aim was to prove that the calcium was the solution, so the calcium should be the ONLY changed variable. I emailed my nurse and told her that I politely declined to take the Flourinef and that I would be discontinuing the Midodrine, as well.

My phosphorus then dropped to 1.6 and PTH to 22 and my doctor told me to start eating as much phosphorus as I wanted, which I did. My BP promptly plummeted back to the 80/40 range within two days of the increase in phosphorus.

(A side note: It seems as though my diastolic BP is struggling to come up more so than my systolic.)

That seemed like proof-positive to me that the calcium was doing the trick so I took it upon myself two weeks ago to increase my calcitriol to .75 mcg per day and also started taking 500 mg of OTC calcium. When I did so my BP went back up to the 100/70 range. The problem is, I can’t tell my center I did that because it wasn’t ordered, but there you have it.

So here’s where things stand now: I’ve stopped the OTC calcium and the extra calcitriol and BP has dropped accordingly (80s/50s). I stated to my center that I wanted to increase my bath to 3.2 CA and my calcitriol to .75 mcg, but the doctor will make no changes until after I draw labs again this month (the reason I stopped the extra calcium and calcitriol), which I suppose is fair enough.

I’m convinced the calcium is doing the trick but I don’t think it’s enough calcium. Here’s my problem: the doctor and the dietician are FREAKED OUT about the slight hypercalcemia and she wants to drop me back down to a 2.5 bath. I don’t think there’s any way in hell she’ll increase the calcium OR the calcitriol (she’s only prescribed .5 mcg per day). They refuse to believe the parathyroidectomy has anything to do with anything even though the problem started almost immediately after the surgery. She wants me to see a neurologist because she thinks it’s neurological even though there is NOTHING to indicate that. She flat-out stated that’s she’s shooting in the dark on this. I am the ONLY one bringing any possible solutions to the table and they are going out of their way to pooh-pooh every study I bring them; I’m quite certain they’ll find a way to dismiss the increase in BP corresponding to the increased calcium, or the dropped BP in response to the lower calcium. They are completely focused on the hypercalcemia to the exclusion of everything else, notwithstanding that I felt 1000% better when my calcium was high.

I asked my doctor, “How many nocturnal patients have you had in your career?” She and the dietician gave each other a blank look and responded, “Well, um, there’s you… um, there was one other before you… and when we had the clinic there were eight, so uh… ten.” A grand total of ten nocturnal patients over the combined course of their careers and I am currently the only nocturnal patient in the entire state of Arizona. So even if I wanted to consult with another neprhologist here - officially - for a second opinion, there’s no one I can consult with because there’s no one who knows anything about nocturnal, no one to back me up. Here’s a funny thing: when I was in-center in NJ the nephrologist there did rounds with me. (Everyone in the clinic made their way to my chair, as a self-care nocturnal patient I was a real curiosity.) He sat and chatted with me for a while and I explained what had been going on with my BP. HE AGREED WITH YOU 100%. So that is not one, but TWO unsolicited second opinions that agree with each other and neither agree with my doctor. She doesn’t want to hear it.

So now I am at the end of my rope and I’m not sure what to do. I KNOW the increased calcium is resolving the problem AND I can demonstrate it but they will not listen. I am afraid they are going to insist on decreasing my bath again and I just can’t do that. I can’t. There is absolutely no point in doing dialysis if the low BP is going to rob me of any semblance of a life. I understand the implications and consequences of hypercalcemia but I am only asking for MILD hypercalcemia. I know the risks but there are risks either way and - if it were up to me - I would rather risk a bit of hypercalcemia and have my life back. They are more concerned with covering their asses than they are about my quality of life and every word out of their mouths has confirmed it.

So, short answer: yes, the calcium was/is the problem. My heart - and the cold, hard numbers on my flowsheets - tell me you are 100% right. Getting my doctor to see it, however, is another matter entirely.

Any more good advice?

Dear Desert Dancer

Thank you so much for your reply, and I am so sorry for the troubled times you have so clearly had over all this.

While I am pleased that you have seen some benefit from my earlier response, I am also saddened that you have had so much trouble implementing what seemed to me like a much needed calcium repletion program.

You will find several papers and abstracts on dialysate calcium … and within those papers, many other refernces as well … to the need for a higher than usual dialysate calcium in nocturnal dialysis.

While our service at Barwon Health is really quite a small dialysis service … we only have about 140 total dialysis patients with currently only 36 at home on home NHD and a further 25 at home on PD (mainly on APD) … our home patient numbers run (usually) at about 40-45% of our patient population and our home NHD have historically ranged between 25-33% of all our HD patients? Over the last decadeamd a half, my team have trained and managed about 80-90 home nocturnal patients, many subsequently’lost’ to successful transplantation as the most frequent pathway out of the NHD program.






As regards calcium … our normal range in SI units is 2.15 - 2.55 … in our home NHD program, we aim to keep our pre-dialysis calcium levels around 2.4-2.45 mmol/l with our post dialysis calciums running up to ~2.65 … the upper limit of our normal being 2.55 … knowing (and we have studied this) that within 4 hrs, the calcium is back down to under 2.55.

What must be understood (and often isnt by those unfamiliar with NHD) is that NHD is a different beast to conventional 3 x 4.5-5 hr facility dialysis. I, and other NHD-familiar, dialysis-nutty nephrologists (like your Bob Lockridge in Virginia) learned about this very early on from our Canadian NHD mentor, Andreas Pierratos … and these differences nowhere better apply than to calcium management.

What can often be forgotten is the reciprocal and unfamiliar normality of … no, more than that … the quite foreign but parallel HYPO-phosphataemia that occurs during NHD. Phosphate removal is so efficient that, as the calcium rises, the phosphate so beautifully falls that the calcium x phosphate product (the much-feared risk factor for vascular calcification) remains firmly fixed well under 3 and usually around 2.5 (our national CARI guidelines recommend it should be kept under 4.0 in CKD and conventional HD to avoid extrosseous calcification) … so, always under 3 and mainle at or under 2.5 is a very nice and low product!


As before, I struggle with unit conversion and do not know what a corresponding US product to 3, 4.5 and 5 might be … Maybe Dori can add later. Again, I apologise for using mmol/l throughout … only the US persists in using the old outmoded mg/dl nomenclature for reasons I have never understood … and it is a major international problem (and danger) that it is so!

Your calcium defecit has clearly been profound. Yes, profound.

Sadly, my guess is that it still is, though you have made up some ground. The need for (and dimension of) aggressive calcium replacement - especially in younger dialysis patients - after parathyroidectomy is both common and, in amount, astounding.

Un-met, and post-operatively, the calcium deficit becomes ‘flattening’ … both at a cardiovascular level and, interestingly enough, at a psychological level too, where depression (sometimes severe) is common if calcium is not maintained through aggressive replacement.

In our NHDs, we routinely use a 1.6 calcium bath for the majority of our current 36 NHDs with a couple being routinely on a 1.75 bath and a few being on a 1.5 bath … aiming for the pre- and post- calcium levels I gave earlier.

Regarding phosphate … our normal range in SI units is 0.75 - 1.4 … our pre- PO4 levels run at +/- 1.3 (max) and post- PO4 levels are +/- 0.65-0.7 with, at any one moment (start to finish) a calcium x phosphate product mean of 2.5-2.75 and never >3.

NB: again please note this calcium x phosphate product is an SI unit - i have no idea what the relevant number is in the US!

As for your bath calcium (dialysate calcium) … i am an ‘old’ codger and come from an age where we actually bathed coils in a bath-like solution - hence the term ‘bath’ … as for your bath calcium, I wouldnt be disturbed to run you against a 1.75 mmol/l dialysate calcium for a short while … maybe for +/- 4 weeks … watching your post dialysis calcium now and then (maybe once a week) to be sure it doesnt exceed 2.75, then dropping back then to a routine 1.6 mmol/l baseline maintenance dialysate calcium bath … ongoing.

I know you feel tee’d off but do try not to be too hard on your nephrologist for she is, likely, in unfamiliar territory.

It’s a bit like starting to work with a NxStage machine (NB: we still use single pass system Fresenius here) … as, with the NxStage, one has to completely rethink and reposition time-honored concepts of how the blood and dialysate interact across the membrane. Similarly, in NHD, there has to be a quite different mindset to the dialysate calcium - a mindset that can be quite difficult to get ones’ head around.

As for the literature, while Nigel Toussaint when he worked with us as our Fellow, wrote quite a bit about this topic, none of this is new or unique to ‘us’ … others have written on this as well … see some of the Canadian work from Pierratos, Chan, Lindsay, and others.

Nigel’s papers are all in the literature: … see our publications on dialysate calcium at http://www.nocturnaldialysis.org in the section buttoned as ‘Papers’ on the home page.

Nb: Our home NHD website is still being upgraded … once you see a button ‘New Technologies’, you will know the upgrade is complete though i apologise that we are having some trouble getting some of New Technology pictures to be visible on Mac computers (no idea why) … so it may take a few more days.

As for you … you need that calcium … so, get it where and as you can. Your team do mean well, but perhaps they are not yet quite as familiar as we are with the different parameters that NHD brings with it.

Do not be afraid of mild hypercalcaemia at the end of your run … especially when it is (as it is) accompanied in NHD by relative and paralleling hypophosphataemia.

In my humble opinion, you NEED that calcium … and badly.

Dr. Agar, thank you so much - again - for taking the time to offer your (unofficial) guidance on this.

In converting your post-dialysis calcium numbers I see that you keep your patients at around 10.6 (US). That corresponds perfectly to my experience; my calcium at its highest was 10.7 and that was also the only time I had normal BP. As soon as my calcium dropped below that number my BP dropped accordingly.

It is my intention to ask my nephrologist to raise my bath to a 3.2 (your 1.6) and my calcitriol to .75 mcg. I do not have any hope she will allow this and in fact, I’m not sure a 3.2 bath is a standard formulation here anyway; I do not see it in my machine’s prescription parameters screen for acid. The next one up from the 3.0 is the 3.5 and I very much doubt she’d consider that, even short-term.

I hope you do not mind if I re-post here my response to MooseMom and others on IHD; I think it rather gets to the real problem:

[i]I wish there were someone to go to for a second opinion but there is not. I am the only nocturnal patient in the state.

Research? I’ve printed out every single paper to which Dr. Agar directed me and printed out copies for the doctor and the dietician. They have found a way to dismiss or counter every paper I’ve brought them with papers of their own trumpeting the dangers of hypercalcemia. I find it interesting that they can expend the effort to shoot down my hypothesis but won’t expend the effort to offer any hypothoses of their own.

The problem with the med changes is this: my clinic told me that they could be shut down if the records are audited and what I am taking does not match what is ordered. If I make any medication changes at all they have to be told immediately so the orders can be changed. With the extra OTC calcium and extra calcitriol I actually did ask first and was answered with a resounding NO! Problem is, the only way I could test the calcium hypothesis and see if my BP came up was to do it, so I did and it worked. However, if I go back to them and say, “See, it worked” it’s the same as saying, “I ignored you, did it anyway and didn’t tell you”. My concern is they will use that as a reason to involuntarily discharge me, since they could say I am endangering my own safety and their jobs.

You know, it might not be a bad idea to volunteer to sign an ‘AMA’ form in exchange for higher calcium. I may certainly end up doing that but what if she refuses even then? What are my options? Can I even GO to a different doctor for my dialysis prescription, one not affiliated with my center?

As for flogging my team, MM: while I like to think I am far more circumspect with my words there than I am here, the naked truth is I am the least tactful person I know and I generally speak my mind with minimal filters. I know this is a problem and believe me, I have struggled mightily to soften my ‘rough edges’ but I have just never, ever been successful in the long term. I’m not nasty or angry and I don’t ridicule. I do state my case aggressively (not loudly), particularly when there is a lack of trust and that could certainly be construed as an attack. I just don’t beat around the bush; why pussyfoot around and take fifteen minutes to say what could have been said in one? It still completely baffles me that people find that offensive but there you have it. I guess it’s an unrealistic expectation for two or more adults to have a conversation where everyone just gets to the point.

Sorry, I got way off track there although the above paragraph does demonstrate a self-created dimension to this whole problem.

Anyway, here is the core problem:

They DO NOT believe the parathyroidectomy is in any way relevant. To them my BP issues are just a coincidence.

They DO NOT believe calcium is the problem. To quote my doctor, they view this increased calcium as “this little experiment of yours”.

They DO NOT believe there is any difference whatsoever between conventional dialysis and nocturnal, calcium-wise. If I can’t convince them of this then where does that leave me? When I explained the communication I was having with Dr. Agar, do you think it helped my case? No, they heard “patient roaming the internets” and shut down.

They DO NOT believe they’re out of their depth with NHHD. They give me the distinct impression that they believe I’m inventing differences just to get my way.

Now tell me: how does someone like me find a way to tactfully say, “You’re out of your depth, here, let me educate you”?!?!? (No, I have not actually said those words. I do have some filters!)

This is a marketing issue on my end and calcium-colored blinders on their end. What I really need is an in-person advocate they would respect. I may be at an impasse.[/i]

Dear Desert Dancer

Just a note re calcitriol and calcium maitenance via a bath calcium of 1.6.

I think the problem is that you didnt get repleted post parathyroidectomy. You are playing late-catch-up football here … a bit like my team, the Cats, tried to do last night!!!

Most of our NHD patients do not need calcitriol … nor binders … nor cinacalcet … just a stable bath calcium of 1.6. But then, far fewer NHD patients ever go on to parathroidectomy when compared with the conventional dialysis group and, as the calcium requirements in NHD are greater too, it suggests that the deficit you neede to make up was even greater than for most.

We have learned - a little by trial and error, too - that, for most on NHD, a 1.5 bath isnt enough and, for most, a 1.75 bath was too much. i think I can safely say that this was the broad experience across most units in Australia and New Zealand … where home dialysis and nocturnal HD are common, ubiquitous therapies.

NB: note my word of caution, though, 3 para’s on …

Originally, we had only 1.5 and 1.75 baths commercially available here, too. But, the ever-helpful team at Fresenius Medical Care (Aust) - at our request - willingly assisted us and has now, for some years, manufactured a specific concentrate for nocturnal dialysis in Australia with a 1.6 bath calcium after a number of NHD units found, like we did, that a 1.6 bath seemed pretty much on the money for most NHD patients.

For a while, we tried alternating 1.5 with 1.75 … which, while it worked OK, was messy and lacked the stability we sought. A 1.6 bath calcium is a very nice solution for NHD.

One word of warning and difference though that may be important … in our unit, as I have oftern noted at this site, we use a 5 night/week, 8-9 hour/treatment regimen in most of our patients and use single pass (not NxStage) systems. Those who are on alternate night (some, though a lesser number of our patients) are, mainly, those who are on 1.5. It seems that, maybe, those that do more hours may need a higher bath calcium.

These differences need to be understood, and programs need to be flexible enough, to individually prescribe and alter, as needed. And we do. We change stuff around, from time to time. No-one is static, all the time. Flexibility is vital. Individuality matters. We cannot, nor should, try to shoe-horn all patients into one mould. Yet, sadly, many seem to try to.

As I said, you are not in a steady state, yet. We have a protocol for post parathyroidectomy calcium repletion - as do all Australian units - that celebrates flexibility by acknowledging the individual variability of post-operative calcium need … some modest, others profound. i suspect you fell into the latter group and are still playing repletion catch-up.

While you may still need calcitriol now (i cant tell exactly, and one needs to know more of any individual patient than one can ever appreciate from the Internet to make such judgements) … once replete, you likely will not.

Indeed, if you are currentl taking 0.75 calcitriol daily, this dose will likely need thoughtful paring back as your calcium stores fill … to 0.5, then 0.25, then off. I cannot tell from the Internet, no matter what numbers are thrown around, when that (those) moment(s) might arrive. So, in my view, it will be your calcitriol dose, and not your bath calcium that will need altering - over time. Your bath, likely, will sit at 1.6.

I know that it sounds like I am dodging the issue, but Internet thoughts are simply that … Internet thoughts. Nothing replaces office consultation, face to face, with all the computerised data, graphs etc. on screen before you and a patient to work with. Your nephrologist is right. Advice from the Internet has huge risks and major limitations. I hope and trust that this site is one where - while always remembering that last sentence - some depth of (hopefuly sensible) clinical experience has been chosen by Dori and her team … whether in HD, PD, access, social work or dietetics.

Your problem is a difficult one. It would be a challenge for any physician and patient pair. It clearly is, for you. Good luck. Keep us in touch with how things pan out. Dont be too harsh on your team … I have yet to meet a physician who doest mean well - though sometimes meaning well doesnt get everyone over the line and sometimes patients fall outside all our normal parameters.

Desert Dancer, the key phrase you said, in my mind, is, “I wish there were someone to go to for a second opinion but there is not. I am the only nocturnal patient in the state.”

You are not the only nocturnal patient in the U.S., though! If your nephrologist is as stymied as she seems, SHE should be reaching out for expertise outside of your clinic and state. I HIGHLY recommend that she contact Bob Lockridge in Lynchburg, VA. He has been mentoring nephrologists across the U.S. and I’m certain that he would want to help you. I’m sure she can Google him to get his phone number, or PM me and I’ll give it to you. You may also want to post this question to our expert dietitian, Leanne Smith, who has worked with all types of dialysis and should have a good grasp of your calcium dilemma.

Dori, yes, PLEASE pass on Bob Lockridge’s contact information! Do you think he would speak to me?

Here is my primary problem: my nephrologist doesn’t believe she’s stymied. She believes I need to go to a neurologist and/or take all the drugs she’s tried to throw at me. My concern is that if I provide her with the number of an expert NHD doctor here in the States, all she is going to hear me say is, “You don’t know what you’re doing so please consult with someone who does” and if that’s the case I don’t know what to do. I can’t force her to consult with anyone but herself. She admits she is “shooting in the dark” (her words) but will not give my/Dr. Agar’s theory any credence.

Thank you for the suggestion that I bring Leanne into the conversation. I would be particularly interested in her thoughts since most of the fear driving the clinical decisions here seems to be emanating from my dietician. I think it’s possible my doctor MAY have considered going further than she has if it weren’t for the dietician having a conniption over just the current changes.

It would probably be easiest to provide Leanne with the link to this conversation rather than trying to start from scratch. I’ll go do that now.

Thank you!