Tag Archives: Dialysis

A vision of kiwi kidneys

Sick of writing boring text reports.  Take a leaf out of Christchurch nephrologist Dr Suetonia Palmer’s (@SuetoniaPalmer) book and make a visual abstract report.  Here are two she has created recently based on data collected about organ donation and end stage renal failure by ANZDATA (@ANZDATARegistry). Enjoy.

Suetonia C-18RfJXUAApRcU

Suetonia C-16lBZXsAERoeM

ps. The featured image is of the Kidney Brothers.  Check out the great educational resources at The OrganWiseGuys.

Send them home

New Zealand is the home of Home Haemodialysis and Christchurch the hub. Sending people home to dialyse is not only more convenient for them and more cost effective, but also has been shown to reduce mortality.  However, is this reduction in mortality sustained across changes in dialysis medicine over time?  This is an important question as Home Haemodialysis is now being considered seriously in many jurisdictions across the world.  The question was recently addressed by Dr Mark Marshall and colleagues across New Zealand and Australia in an article which appeared online ahead of print a couple of weeks back in the American Journal of Kidney Disease (see here, sadly behind a paywall).

What they did

Step 1 was to extract data from 1998 to 2012 from the Australia New Zealand Dialysis & Transplant Registry which prospectively collects information for all long term renal replacement therapy patients. This is a very important registry and the study highlights the importance of keeping data in this way.

Step 2 Placed patients into one of three time periods according to when they started their dialysis: 1998-2002, 2003-2007, 2008-2012.

Step 3: Identified the exposure of the patients to one of: Facility lead haemodialysis (facility HD), Home haemodialysis (home HD), or Peritoneal dialysis (PD).

Step 4: Compared rates of death for patients starting in each time period for each of the dialysis modalities after accounting for age, sex, ethnicity, primary kidney disease, and glomerular filtration rate at the start of therapy (ie how well the kidney was functioning).

What they found (with my commentary)

there is demonstrable survival benefit associated with recent era irrespective of the landmark initiation time.

Indeed, it was a 25% lower (adjusted) mortality for those starting dialysis in  2008-2012 compared to the 1998-2002.

Well done kidney docs – they are getting better and keeping people alive.

There is significant effect modification by modality [type of dialysis] (P <0.001), and separate models were developed in each subgroup: there is a 23% corresponding reduction for those on facility HD therapy, a 29% reduction for those on PD therapy, and a 46% reduction for those on home HD therapy

In other words, all things being equal, survival was improved more on home haemodialysis than either of the other types.

Hazard ratios for death according to era and mode of dialysis.  Lower numbers are better!  From: Marshall, M. R., Polkinghorne, K. R., Kerr, P. G., Agar, J. W. M., Hawley, C. M., & McDonald, S. P. (2015). Temporal Changes in Mortality Risk by Dialysis Modality in the Australian and New Zealand Dialysis Population. American Journal of Kidney Diseases : the Official Journal of the National Kidney Foundation. doi:10.1053/j.ajkd.2015.03.014

Hazard ratios for death according to era and mode of dialysis. Lower numbers are better! From: Marshall, M. R., Polkinghorne, K. R., Kerr, P. G., Agar, J. W. M., Hawley, C. M., & McDonald, S. P. (2015). Temporal Changes in Mortality Risk by Dialysis Modality in the Australian and New Zealand Dialysis Population. American Journal of Kidney Diseases : the Official Journal of the National Kidney Foundation. doi:10.1053/j.ajkd.2015.03.014

I note patients were only around 60 years old on average when they first initiated dialysis, yet 37% died before the end of the study period or could receive a transplant.  Folks – do your damnedest to avoid kidney disease – starting with avoiding diabetes.

Conclusions

  1. Survival has increased during the past 15 years
  2. Survival of peritoneal dialysis patients has increased more than facility haemodialysis patients
  3. The relative survival of home haemodialysis patients has improved the most

Has home haemodialysis caused people to survive longer?  This study can’t say, because it is an association study not one set out to demonstrate causation. However, it is evidence that supports the continued use and possibly even expansion of home dialysis in New Zealand and Australia.

For further reading, refer to the paper itself:

Marshall, M. R., Polkinghorne, K. R., Kerr, P. G., Agar, J. W. M., Hawley, C. M., & McDonald, S. P. (2015). Temporal Changes in Mortality Risk by Dialysis Modality in the Australian and New Zealand Dialysis Population. American Journal of Kidney Diseases : the Official Journal of the National Kidney Foundation. doi:10.1053/j.ajkd.2015.03.014

Cheesecake files: Just how deadly is it?

Everyone said it did, but how did they know and by how much?  Statements like

“The development of AKI [Acute Kidney Injury] after CPB [Cardiopulmonary Bypass Surgery] is associated with a significant increase in infectious complications, an increase in length of hospital stay, and greater mortality.” (Kumar & Suneja, Anaesthesiology 2011 14(4):964)

are common place in the acute kidney injury literature.  When I started to look at the references for such statements I realised that they were all to individual, normally single centre, studies and that the estimates of the increased risk associated with AKI after CPB varied considerably.  Furthermore, the way AKI is defined in these studies is quite varied. This lead to two questions?

  1. Just how deadly is getting AKI after CPB?
  2. Does it matter how we define AKI in this case?

These questions are important as the answer to them helps a surgeon and patient to better assess the risk associated with choosing to have cardiopulmonary bypass surgery and what the importance is in monitoring kidney function after such a surgery.  To answer these questions required a meta-analysis the results of which I have just published (a.k.a earned a cheesecake).  A meta-analysis involves systematically searching through the literature, a sentence which takes seconds to write but months to serve, for all articles reporting an association between AKI and mortality after CPB.  Then there is learning how to put all the, sometimes disparate, data together (I had to learn a lot of R for this one) and to report on it.  As this was my first meta-analysis, I was fortunate to have the assistance of two highly competent scientists & nephrologists with meta-analysis experience, namely Dr’s Matt James of Calgary, and Suetonia Palmer of my own department in the University of Otago Christchurch.

So – what did we find?

  1. If you get AKI after CPB you about 4 time more likely to die compared to if you do not get AKI after CPB even after accounting for things like age, diabetes, and other risk factors.
  2. Somewhere between 37 and 118 lives per 10,000 CPB operations could be saved if we could find a way to eliminate AKI.
  3. How AKI was measured did not make any difference to the results.
  4. AKI after CPB was also associated with increased risk of stroke.
Figure 1 from Pickering et al, AJKD 2014

A teaser of a figure from Pickering et al, AJKD 2014

Pickering, J. W., James, M. T., & Palmer, S. C. (2014). Acute Kidney Injury and Prognosis after Cardiopulmonary Bypass: A Meta-analysis of Cohort Studies. American Journal of Kidney Diseases : the Official Journal of the National Kidney Foundation. doi:10.1053/j.ajkd.2014.09.008

ps. Sorry about the paywall folks, but as I’ve said before, if we want to put this data in front of the people it is most relevant to we haven’t the budget to always make them Open Access.

 

Can Doctors and Nurses help Dialysis patients recover?

In the case of dialysis dependent acute kidney injury patients this is a question which Dr Dinna Cruz  and colleagues (University of California San Diego) are asking and seeking opinions from both nephrologists and non-nephrologist doctors and nurses involved in care of dialysis patients.  It was a question which arose out of discussions at this year’s Continuous Renal Replacement Therapies conference (CRRT 2014). Personally, I think it is a brilliant starting point for research to go out and seek the opinion of those “at the coal face” actually treating patients. If that includes you, please take a moment to complete the survey. If it includes someone you know, please pass this request to participate on.  Here is Dr Cruz’s request:

Currently there is much interest regarding the recovery aspect of AKI. A specific area of interest is how to enhance recovery in patients who remain dialysis-dependent at the time of discharge. It is hypothesized that patients with potential for renal recovery may require a different care plan than the “usual” ESRD patient.

Therefore we are asking your opinion regarding the post-discharge care of such patients, using this short survey. It will take only a few minutes of your time, and represents a starting point for developing potential strategies for these patients. We think it is very important to have the input of specialists from different healthcare settings and countries to give a more balanced view.

Kindly complete the survey appropriate for your specialty, then please share both these links with other colleagues so we get more responses from around the world

For nephrologists:

https://www.surveymonkey.com/s/postdischAKIcare_neph

For non-nephrologists, including acute and chronic dialysis nurses:

https://www.surveymonkey.com/s/postdischAKIcare

Thank you very much for your help!

Source: Anna Frodesiak-Wikimedia Commons

Source: Anna Frodesiak-Wikimedia Commons

Cheesecake files: Of bathtubs and kidneys

Sitting in the bathtub you notice that there is a slow leak around the plug.  You adjust the taps to maintain a flow of water that exactly counteracts the loss due to the leak; the water level stays constant.  This is called a steady state and the same thing happens with out kidneys and the molecule used to assess their function.  Our bodies generate creatinine at a constant rate which finds its way into the blood.  Under normal circumstances our kidneys excrete that creatinine into the urine at the same constant

rate.  The creatinine concentration in the blood, therefore, stays constant.  When our kidneys get injured (as they very often do in hospitalised patients) this is like plugging the leak.  Just as the water level in the bathtub would rise slowly – undetectable at first – so too does the creatinine concentration rise slowly.  It normally takes a couple of days to be noticed.  Most of my work has been about trying to detect this injury to the kidney early.  However, if the kidneys start to recover then excess creatinine is only slowly cleared from the blood by the kidney – a process that similarly can take a day or two before it is detected.  Just as not knowing if the kidneys have been harmed makes treatment and drug dosing difficult for the nephrologists and intensivists, so too is not knowing if they have recovered.  My latest publication (aka a cheesecake file) that has appeared in press presents a simple tool for the physicians to try and determine if kidney function has recovered after having been compromised.

This particular piece of work began when a St Louis Nephrologists (a kidney doc), Dr John Mellas, contacted me to say that although a manuscript of his had been rejected by reviewers, he thought there was merit and could I help him (he found me through a search of the literature).  I confessed to being one of the reviewers who had rejected the manuscript!  Fortunately, John was forgiving.  His problem was that he was called in to the intensive care unit to look at a patient with high blood creatinine concentration.  Should he put the patient on dialysis or should he wait?  If he knew if the kidney was already recovering, then he would be less likely to put on dialysis. We talked about the issue for a while and eventually settled on a possible tool which we could test by looking at the behaviour of creatinine over time in abut 500 patients in the ICU.  The tool is quite simple.  It is the ratio of the creatinine that is excreted to the creatinine that is generated.  If more creatinine is being generated than excreted then probably the kidney function is still below normal, however, if more is excreted than generated then probably the kidney is recovering.  The difficulty is that there is no way to measure in an individual what the creatinine generation is.  We ended up using equations based on age, sex, and weight to estimate creatinine generation.  This is a bit like using an equation which takes into account pipe diameter, mains water pressure, and how many turns of the screw the tap has had to determine the rate of water flow.  Creatinine excretion, though, can be easily measured by recording total urine production over several hours (we suggest 4h) and multiplying this by the concentration of creatinine in the urine.

We discovered that by using the ratio between estimated creatinine generation and creatinine excretion we were able to tell in most patients if the kidney was recovering or not.  My hope is that physicians will test this out for themselves.  The good thing is that it requires only minimal additional measurements (and costs) beyond what are already made in ICUs, yet may save many from expensive and invasive dialysis.

Pickering, J. W., & Mellas, J. (2014). A Simple Method to Detect Recovery of Glomerular Filtration Rate following Acute Kidney Injury. BioMed Research International, 2014. doi:10.1155/2014/542069

 

A day to celebrate

If it weren’t for your kidneys where would you be?

You’d be in the hospital or infirmary,

If you didn’t have two functioning kidneys.

(with apologies to John Clarke aka Fred Dagg)

Happy World Kidney Day everyone.

This blog started off life as $100 Dialysis because I believe that if we can make a computer for $100 then surely we can do the same for dialysis!  Dialysis is a life saver, yet its cost kills as so many can not afford the treatment.

There’s some good news in the dialysis world.

Schematics of the zeolite nanonfibres and how they may look in practice

Schematics of the zeolite nanonfibres and how they may look in practice

Just last week the MANA – International Centre for Materials NanoArchitectionics announced  they have developed a method to remove waste from the blood using an easy-to-produce nanofibre mesh.  Importantly, they claim it is cheap to produce.  Details were published in Biomaterials Science (free access).  Despite the photograph, there have been no human studies yet, but I expect that won’t be too long in the future.

Dr Victor Gura and the Wearable Artificial Kidney (WAK)

Dr Victor Gura and the Wearable Artificial Kidney (WAK)

In the meantime, the FDA gave approval last month for human trials of a wearable dialysis device produced by Blood Purification Technologies Inc (the WAK).

New Zealand, and Dunedin and Christchurch in particular, lead the way in Home Dialysis.  One Dunedin tradesman has even taken Home Dialysis a step further and turned it into portable dialysis by dialysing in his work van during his lunch hour. Of course, those needing a holiday may go on the road in specially equipped camper vans (http://www.kidneys.co.nz/Kidney-Disease/Holiday-Dialysis/).

Cause for celebration in the New Zealand kidney community was the gong (Office of the New Zealand Order of Merit) given to Adrian Buttimore who for 40 years managed Christchurch’s dialysis service.

These are just a few pieces of good news as doctors and scientists work around the world to improve the lives of dialysis patients.

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Hot off the Press… I couldn’t resist adding this…. Pee, the answer to the world’s energy problems. http://www.bbc.com/future/story/20140312-is-pee-power-really-possible

 

A taste of success

Some recent successes of University of Otago Christchurch researchers:

Chlorine bleach key in disease?

Professor Tony Kettle from the Centre for Free Radical Research has won a prestigious Marsden Fund grant to better understand a ‘Jekyll and Hyde’ chemical with a role in heart disease, cancer, cystic fibrosis, and rheumatoid arthritis.

Professor Kettle will investigate chlorine bleach’s role in strengthening collagen by linking to form a resilient mesh. Without this mesh people can develop cataracts and an autoimmune disease that destroys the kidneys and causes the lungs to hemorrhage. However bleach can also have negative effects.

“Chlorine bleach should be viewed as a natural chemical with a Jekyll and Hyde personality. It helps us to fight infections and form strong connective tissue but also endangers our health during uncontrolled inflammation.”

Professor Kettle and his team will work with researchers from Vienna and Budapest on the project.

Improving the treatment and experience for dialysis patients

Chronic kidney disease is common, affecting about 500,000 New Zealanders. It is important because it increases chances of heart disease and death and may lead to needing treatment with dialysis or a kidney transplant. Dialysis therapy is a heavy and costly burden for patients and their families and the health system. However, there is a lack of reliable evidence to improve patient outcomes.

Dr Suetonia Palmer has just been awarded a prestigious Rutherford Discovery Fellowship valued at $800,000 over five years for research project called: “Improving evidence for decision-makers in chronic kidney disease.”

Dr Palmer’s research aims to to provide rigorous overviews of existing research and participant-led enquiry to provide better and more useable information for clinicians, consumers and policy-makers in the field of chronic kidney disease.

Recovering from food addiction

Professor Doug Sellman and his team from the National Addiction Centre have just been granted funding to trial a new treatment for those with obesity called Kia Akina.

“There is a serious need to develop new non-surgical ways of treating obesity because obesity-related diseases are expensive for New Zealand, traditional non-surgical methods are not working, and surgery is very costly,” says Professor Sellman.

Kia Akina uses a ‘food addiction’ approach to obesity. Professor Sellman says the project will test the feasibility, short-term effectiveness and participant satisfaction ofKia Akina within a primary health care setting.

If shown to be effective, Kia Akina will be developed as a non-commercial, low cost network for obesity recovery throughout New Zealand.

Innovation in Indigenous Health

Christchurch’s Maori/Indigenous Health Institute (MIHI) recently won the Australasian award for ‘innovation in Indigenous health curriculum implementation’ at the Leaders in Indigenous Medical Education (LIME) conference.

The LIME conference brings together all 20 medical schools throughout Australia and New Zealand, and hosts attendees from the United States and Canada.

Staff and students of the University of Otago, Christchurch, in Darwin at the Leaders in Indigenous Medical Education (LIME) conference

Staff and students of the University of Otago, Christchurch, in Darwin at the Leaders in Indigenous Medical Education (LIME) conference

MIHI director Suzanne Pitama says she and her team were thrilled to receive the award. As there is much collaboration between indigenous teaching teams at University of Otago’s Christchurch, Wellington and Dunedin campuses, the award recognises the innovation of all these teams.  It also recognised the systemic support within the University of Otago to prioritise indigenous health within the curriculum.

MIHI oversees the Maori health component of the medical curriculum at the University of Otago, Christchurch.

Award nominees are judged on how well their teaching programmes demonstrate their commitment and experience to understanding and furthering the health of Maori and Indigenous peoples.

The award has been presented for four years, says Pitama. MIHI also won it in the inaugural year.

A review panel of academic peers and members of indigenous medical doctors associations judge the award, Pitama says.

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This guest post was written by Kim Thomas,  Senior Communications Advisor, University of Otago, Christchurch, www.uoc.otago.ac.nz.