Advantages and challenges of increasing the duration and frequency of dialysis

Nature Clinical Practice Nephrology
Published online: 25 November 2008 | doi:10.1038/ncpneph0979
Received 3 July 2008 | Accepted 12 September 2008

The advantages and challenges of increasing the duration and frequency of maintenance dialysis sessions

Charles Chazot* and Guillaume Jean About the authors

Correspondence *Centre de Rein Artificiel, 42 Avenue du 8 Mai 1945, 69160 Tassin, France

Email chchazot@wanadoo.fr

Home > Advance online publication > Review > Full Text
Review

Continuing Medical EducationNature Clinical Practice Nephrology
Published online: 25 November 2008 | doi:10.1038/ncpneph0979
Received 3 July 2008 | Accepted 12 September 2008

The advantages and challenges of increasing the duration and frequency of maintenance dialysis sessions

Charles Chazot* and Guillaume Jean About the authors

Correspondence *Centre de Rein Artificiel, 42 Avenue du 8 Mai 1945, 69160 Tassin, France

Email chchazot@wanadoo.fr
Medscape logo

Medscape Continuing Medical Education online
Medscape, LLC is pleased to provide online continuing medical education (CME) for this journal article, allowing clinicians the opportunity to earn CME credit. Medscape, LLC is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide CME for physicians. Medscape, LLC designates this educational activity for a maximum of 1.0 AMA PRA Category 1 Credits™. Physicians should only claim credit commensurate with the extent of their participation in the activity. All other clinicians completing this activity will be issued a certificate of participation. To receive credit, please complete the post-test.

Learning objectives

Upon completion of this activity, participants should be able to:

1. List the alternative options to conventional hemodialysis.
2. List the adverse effects of dialysis associated with a high ultrafiltration rate.
3. Describe the main benefits associated with increasing the frequency and duration of dialysis.
4. Identify the dialysis approach associated with more effective phosphate removal.
5. Describe the survival advantage associated with greater dialysis frequency and duration.

Competing interests

The authors have declared an association with the following company: Fresenius Medical Care. See the article online for full details of the relationships. The Locum Journal Editor C Harman and the CME questions author D Lie declared no competing interests.

To complete the questions online and earn continuing education credits, you must be a registered user on Medscape.com. If you are not registered on Medscape.com please click on the New Users: Free Registration link on the top left-hand side of the website to register. Registration is free. For questions regarding the content of this activity, contact the accredited provider for this CME activity: CME@medscape.net. For technical assistance, contact CME@webmd.net.
Summary

The duration and frequency of hemodialysis was determined empirically when this therapy first came into use, and treatment was commonly three 8 h sessions per week by the end of the 1960s. Subsequently, however, the growing number of patients who required this therapy had to be reconciled with the shortage of equipment; therefore, dialysis time was decreased to three 4 h sessions per week. At the same time, on the basis of data from the first randomized controlled trial of dialysis—the National Cooperative Dialysis Study—Kt/Vurea was devised as the optimum measure of dialysis adequacy. Nowadays, although Kt/Vurea targets are fulfilled in an increasing number of patients, observational studies show that individuals on hemodialysis continue to experience a high rate of complications, including hypertension, left ventricular hypertrophy, cardiac failure, hyperphosphatemia, malnutrition and death. Although no randomized controlled trial has yet been published, observational data indicate that increasing hemodialysis time and/or frequency improves a number of these complications, especially the death rate. This Review outlines the advantages of longer and/or more frequent dialysis sessions and highlights the barriers to adoption of such regimens, which largely relate to economics, patient willingness, and organization of dialysis units.
Review criteria

Data for this Review were obtained from peer-reviewed articles, reviews and letters indexed on PubMed. Search terms included "dialysis", "daily", "frequency", "long", "short" and "nocturnal". No date or language restriction was placed on the search.
Keywords:

extracellular volume, frequency, hemodialysis, phosphate, time
Top of page
Introduction

Since the early 1960s, patients with end-stage renal disease (ESRD) have benefited from hemodialysis, which prolongs their survival. The usual hemodialysis prescription is currently thrice-weekly sessions of 3–4 h each (conventional hemodialysis [CHD]); this regimen was gradually defined after the introduction of hemodialysis. The first dialysis session for Clyde Shields, who was the first patient to be treated with this modality, lasted for 76 h!1 At the end of the 1960s, chronic hemodialysis usually involved three 8–12 h sessions per week.2, 3, 4, 5 As the demand for therapy became overwhelming, the treatment time was shortened to three 4 h sessions per week, since the clinical outcomes of this regimen were considered to be acceptable.6 However, a registry analysis by Degoulet et al.7 in 1982 revealed a high incidence of intradialytic adverse effects and a high rate of cardiovascular mortality in patients on hemodialysis, although no direct relationship between hemodialysis practice and patient outcome was identified. Patients on dialysis are now known to have a significantly increased rate of death, mainly of a cardiovascular cause, compared with the general population,8 and nephrologists who care for these individuals are actively looking for ways to improve their patients' outcomes. To this end, a number of alternative dialysis strategies, such as short daily hemodialysis (SDHD), long nocturnal daily hemodialysis (LNDHD), long conventional hemodialysis (LHD) and hemodiafiltration, are currently being investigated. This Review summarizes the benefits of and barriers to adoption of these regimens.

Read entire article here: http://www.nature.com/ncpneph/journal/vaop/ncurrent/full/ncpneph0979.html