- Email: [email protected]
A wearable haemodialysis device – Authors' reply
Correspondence
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Many observational studies with corrections for case-mix4 and also one randomised controlled trial5 have shown that survival on peritoneal dialysis is superior to that on haemodialysis, at least during the first years of treatment, probably because of better preservation of residual renal function and fewer hypovolaemic episodes. Therefore, I consider it inappropriate to discuss the potential future role of the wearable haemodialysis device without even mentioning peritoneal dialysis and to publish (twice) a photograph of a happy-looking patient wearing a 5 kg girdle. Each dialysis modality can provide similar pictures and the patient involved does not necessarily receive the best dialysis treatment. Any modification of haemodialysis to make it more continuous should be welcomed, but such modifications should take the excellent results of modern peritoneal dialysis into account. I declare that I have no conflict of interest.
Raymond T Krediet [email protected] Division of Nephrology, Department of Medicine, Academic Medical Centre, University of Amsterdam, PO Box 22700, 1100 DE Amsterdam, Netherlands 1
2 3
4
5
Davenport A, Gura V, Ronco C, Beizai M, Ezon C, Rambod E. A wearable haemodialysis device for patients with end-stage renal failure: a pilot study. Lancet 2007; 370: 2005–10. Eknoyan G. Artificial kidneys: progress and promise. Lancet 2007; 370: 1977–78. European Best Practice Guidelines Working Group on Peritoneal Dialysis. European best practice guidelines for peritoneal dialysis. Nephrol Dial Transplant 2005; 20 (suppl 9): 1–27. Krediet RT, Boeschoten EW, Dekker FW. Why is the evidence favouring hemodialysis over peritoneal dialysis misleading? Semin Dial 2007; 20: 205–08. Korevaar JC, Feith GW, Dekker FW, et al. Effect of starting hemodialysis compared with peritoneal dialysis in patients new on dialysis treatment: a randomized controlled trial. Kidney Int 2002; 62: 1046–53.
Authors’ reply Stanley Shaldon and Rosemarie Baillod started a home haemodialysis programme based at the Royal Free Hospital in the UK, which grew and provided treatment to more than 90 patients at its peak in the 1970s. However, over time, the number 1164
of home haemodialysis patients treated by the Royal Free steadily declined to a nadir of just 11 last year. This is not because home haemodialysis is by any means an inferior treatment. It reflects changes, not only in patient demographics and increasing comorbidities, but also the development and provision of both main and satellite haemodialysis facilities within the UK. This downward trend in home haemodialysis is despite a policy statement from the National Institute for Health and Clinical Excellence (NICE) in 2002, which advocated home haemodialysis as an important treatment option for patients with chronic kidney disease (CKD).1 Although more than 100 000 patients are treated by peritoneal dialysis worldwide, there similarly has been a decline in the proportion of patients with CKD treated by peritoneal dialysis, particularly in the USA. Indeed, there is now a Canadian Government initiative to try to increase the proportion of patients treated by peritoneal dialysis in Ontario, where numbers have slipped down to around 18%, despite Toronto being one of the major pioneering centres behind the development of peritoneal dialysis.2 Thus, in both North America and Europe, most patients with CKD are treated by intermittent thrice weekly haemodialysis in a main hospital, and an ever-increasing number of satellite dialysis centres. Thus, as currently practised, haemodialysis is a very expensive treatment. In addition, owing to time constraints, and the intermittent nature of the therapy, several kilos of fluid often have to be removed over a relatively short period of time, potentially resulting in hypotension. A UK audit3 reported that some 15% or so of outpatient haemodialysis treatments were complicated by hypotension, requiring active fluid resuscitation. Furthermore, there is mounting evidence to show the benefits of daily haemodialysis. Unfortunately, there is currently no
logistical, practical, or economically feasible way to provide such therapy to most patients with CKD. To try to improve not only the quality of care delivered, but also patients’ quality of life, we have been working to develop wearable devices that would allow for an outpatientbased treatment for both chronic heart failure4 and end-stage kidney disease.5 As such we have recently reported our first pilot studies. Our pilot trial of the wearable artificial haemodialysis device was approved by the UK Medicines Health Regulatory Authority (MHRA), and as such the design of the trial, in terms of the number of patients, duration of therapy, and safety assessments was stipulated by the MHRA. Samples were analysed in the routine laboratories at the Royal Free Hospital, and as such the data were collected by the hospital laboratory data management system. Data were analysed by AD, who wrote the initial drafts. We wish to thank our sponsors, XCorporeal Inc and the Special Trustees of the Royal Free Hospital, who made this study possible. VG is chief medical and scientific officer to Xcorporeal Inc, Los Angeles, CA, USA.
*Andrew Davenport, Claudio Ronco, Victor Gura [email protected] Royal Free and University College Medical School, London NW3 2PF, UK (AD); Divisione de Nefrologia, Ospedale San Bortolo, Vicenza, Italy (CR); and Cedars Sinai Medical Center, University of California Los Angeles, Los Angeles, CA, USA (VG) 1
2
3
4
5
National Institute for Clinical Excellence. Guidance on home versus hospital haemodialysis for patients with end-stage renal failure. London: NICE, 2002. http://www. nice.org.uk/nicemedia/pdf/HvH_full_ guidance.pdf (accessed March 10, 2008). Oreopoulos DG, Coleman S, Doyle E. Reversing the decreasing peritoneal dialysis (PD) trend in Ontario: a government initiative to increase PD use in Ontario to 30% by 2010. Perit Dial Int 2007; 27: 489–95. Davenport A, Cox C, Thuraisingham R. Achieving blood pressure targets during dialysis improves control but increases intradialytic hypotension. Kidney Int 2008; 73: 759–64. Gura V, Ronco C, Nalesso F, et al. A wearable hemofilter for continuous ambulatory ultrafiltration. Kidney Int 2008; 73: 497–502. Davenport A, Gura V, Ronco C, Beizai M, Ezon C, Rambod E. A wearable haemodialysis device for patients with end-stage renal failure: a pilot study. Lancet 2007; 370: 2005–10.
www.thelancet.com Vol 371 April 5, 2008
Science Photo Library
Many observational studies with corrections for case-mix4 and also one randomised controlled trial5 have shown that survival on peritoneal dialysis is superior to that on haemodialysis, at least during the first years of treatment, probably because of better preservation of residual renal function and fewer hypovolaemic episodes. Therefore, I consider it inappropriate to discuss the potential future role of the wearable haemodialysis device without even mentioning peritoneal dialysis and to publish (twice) a photograph of a happy-looking patient wearing a 5 kg girdle. Each dialysis modality can provide similar pictures and the patient involved does not necessarily receive the best dialysis treatment. Any modification of haemodialysis to make it more continuous should be welcomed, but such modifications should take the excellent results of modern peritoneal dialysis into account. I declare that I have no conflict of interest.
Raymond T Krediet [email protected] Division of Nephrology, Department of Medicine, Academic Medical Centre, University of Amsterdam, PO Box 22700, 1100 DE Amsterdam, Netherlands 1
2 3
4
5
Davenport A, Gura V, Ronco C, Beizai M, Ezon C, Rambod E. A wearable haemodialysis device for patients with end-stage renal failure: a pilot study. Lancet 2007; 370: 2005–10. Eknoyan G. Artificial kidneys: progress and promise. Lancet 2007; 370: 1977–78. European Best Practice Guidelines Working Group on Peritoneal Dialysis. European best practice guidelines for peritoneal dialysis. Nephrol Dial Transplant 2005; 20 (suppl 9): 1–27. Krediet RT, Boeschoten EW, Dekker FW. Why is the evidence favouring hemodialysis over peritoneal dialysis misleading? Semin Dial 2007; 20: 205–08. Korevaar JC, Feith GW, Dekker FW, et al. Effect of starting hemodialysis compared with peritoneal dialysis in patients new on dialysis treatment: a randomized controlled trial. Kidney Int 2002; 62: 1046–53.
Authors’ reply Stanley Shaldon and Rosemarie Baillod started a home haemodialysis programme based at the Royal Free Hospital in the UK, which grew and provided treatment to more than 90 patients at its peak in the 1970s. However, over time, the number 1164
of home haemodialysis patients treated by the Royal Free steadily declined to a nadir of just 11 last year. This is not because home haemodialysis is by any means an inferior treatment. It reflects changes, not only in patient demographics and increasing comorbidities, but also the development and provision of both main and satellite haemodialysis facilities within the UK. This downward trend in home haemodialysis is despite a policy statement from the National Institute for Health and Clinical Excellence (NICE) in 2002, which advocated home haemodialysis as an important treatment option for patients with chronic kidney disease (CKD).1 Although more than 100 000 patients are treated by peritoneal dialysis worldwide, there similarly has been a decline in the proportion of patients with CKD treated by peritoneal dialysis, particularly in the USA. Indeed, there is now a Canadian Government initiative to try to increase the proportion of patients treated by peritoneal dialysis in Ontario, where numbers have slipped down to around 18%, despite Toronto being one of the major pioneering centres behind the development of peritoneal dialysis.2 Thus, in both North America and Europe, most patients with CKD are treated by intermittent thrice weekly haemodialysis in a main hospital, and an ever-increasing number of satellite dialysis centres. Thus, as currently practised, haemodialysis is a very expensive treatment. In addition, owing to time constraints, and the intermittent nature of the therapy, several kilos of fluid often have to be removed over a relatively short period of time, potentially resulting in hypotension. A UK audit3 reported that some 15% or so of outpatient haemodialysis treatments were complicated by hypotension, requiring active fluid resuscitation. Furthermore, there is mounting evidence to show the benefits of daily haemodialysis. Unfortunately, there is currently no
logistical, practical, or economically feasible way to provide such therapy to most patients with CKD. To try to improve not only the quality of care delivered, but also patients’ quality of life, we have been working to develop wearable devices that would allow for an outpatientbased treatment for both chronic heart failure4 and end-stage kidney disease.5 As such we have recently reported our first pilot studies. Our pilot trial of the wearable artificial haemodialysis device was approved by the UK Medicines Health Regulatory Authority (MHRA), and as such the design of the trial, in terms of the number of patients, duration of therapy, and safety assessments was stipulated by the MHRA. Samples were analysed in the routine laboratories at the Royal Free Hospital, and as such the data were collected by the hospital laboratory data management system. Data were analysed by AD, who wrote the initial drafts. We wish to thank our sponsors, XCorporeal Inc and the Special Trustees of the Royal Free Hospital, who made this study possible. VG is chief medical and scientific officer to Xcorporeal Inc, Los Angeles, CA, USA.
*Andrew Davenport, Claudio Ronco, Victor Gura [email protected] Royal Free and University College Medical School, London NW3 2PF, UK (AD); Divisione de Nefrologia, Ospedale San Bortolo, Vicenza, Italy (CR); and Cedars Sinai Medical Center, University of California Los Angeles, Los Angeles, CA, USA (VG) 1
2
3
4
5
National Institute for Clinical Excellence. Guidance on home versus hospital haemodialysis for patients with end-stage renal failure. London: NICE, 2002. http://www. nice.org.uk/nicemedia/pdf/HvH_full_ guidance.pdf (accessed March 10, 2008). Oreopoulos DG, Coleman S, Doyle E. Reversing the decreasing peritoneal dialysis (PD) trend in Ontario: a government initiative to increase PD use in Ontario to 30% by 2010. Perit Dial Int 2007; 27: 489–95. Davenport A, Cox C, Thuraisingham R. Achieving blood pressure targets during dialysis improves control but increases intradialytic hypotension. Kidney Int 2008; 73: 759–64. Gura V, Ronco C, Nalesso F, et al. A wearable hemofilter for continuous ambulatory ultrafiltration. Kidney Int 2008; 73: 497–502. Davenport A, Gura V, Ronco C, Beizai M, Ezon C, Rambod E. A wearable haemodialysis device for patients with end-stage renal failure: a pilot study. Lancet 2007; 370: 2005–10.
www.thelancet.com Vol 371 April 5, 2008