The current version is shown below. Printable files for the current version as well as previous versions can be downloaded from the box to the right. The current version is the final version following a period for feedback. The current version is not likely to be changed until the next formal revision in 2009.

1. Haemodialysis facilities

1.1 The specification of new or refurbished haemodialysis facilities should adhere to the guidelines that are described in the NHS Estates Health Building Note 53: Volumes 1 & 2.

1.2 The haemodialysis facility should have sufficient specialist support staff to fulfill the criteria listed by the Renal Workforce Planning Group 2002.

1.3 Except in remote geographical areas the travel time to a haemodialysis facility should be less than 30 minutes or a haemodialysis facility should be located with 25 miles of the patient’s home. In inner city areas travel times over short distances may exceed 30 minutes at peak traffic flow periods during the day.

1.4 Haemodialysis patients who require transport should be collected from home within 30 minutes of the allotted time and be collected to return home within 30 minutes of finishing dialysis.

1.5 All patients who may be suitable for home dialysis should receive full information and education about home haemodialysis. Home haemodialysis training is not available in all renal units and some patients may need to travel to a sub-regional or regional centre to pursue their choice to train for home haemodialysis.

1.6 Haemodialysis capacity in satellite and main renal units within a geographical area should increase in step with predicted need. To allow for patient choice regarding out of hours haemodialysis schedules, provision of holiday haemodialysis and expansion in patient numbers calculation of the required number of haemodialysis stations should be based on using each station for 2 patients per day three times per week. The national average number of hospital haemodialysis patients per million catchment population reported for the previous year by the UK Renal Registry should be regarded as the minimum capacity for haemodialysis in each geographically based renal service. Alternatively up-to-date regional data may be used. For example the national average provision for 312 hospital haemodialysis patients (78 stations) per million catchment population in Scotland at the end of 2005 may be regarded as a minimum haemodialysis capacity in all regions in 2006. The level of hospital haemodialysis provision will need to be higher in areas with a high ethnic and/or elderly population and increase nationwide over the next 10 years.

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2. Haemodialysis equipment and disposables

2.1 All equipment used in the delivery and monitoring of therapy should comply with the relevant standards for medical electrical equipment. General electrical safety standards are covered by BS EN 60601-1; 2006 and specific dialysis machine requirements are covered by BS-EN 60601-2-16: 1998 (Medical electrical equipment: Particular requirements for the safety of haemodialysis (HD), haemodiafiltration and haemofiltration equipment).

2.2 Disposables such as dialysers and associated devices are classified as medical devices and should display the CE mark. The presence of such a mark signifies compliance with the national and international standards: haemodialysers, haemodiafilters, haemofilters, haemoconcentrators and their extracorporeal circuits (BS-EN 1283: 1996). Plasma filters (BS/150 13960).

2.3 Machines should be replaced after between seven and ten years’ service or after completing between 25,000 and 40,000 hours of use for haemodialysis, depending upon an assessment of machine condition.

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3. Concentrates and water for haemodialysis

3.1 Ready made concentrates are classified as medical devices and should display the CE mark. Concentrates that are manufactured ‘in house’ should meet the requirements of BS EN 13867: 2002 (Concentrates for haemodialysis and related therapies) and Europoean Pharmacopoeia 2003 (Solutions for haemodialysis). (Good practice)

3.2 Water used in the preparation of dialysis fluid should as a minimum meet the requirements stated in Table 1 for chemical and microbiological contaminants. After consultation within the UK the limits for chemical contaminants are derived from AAMI RD-52 2004 (1), ISO 13959:2002 (2) and the European Pharmacopoeia (3), whilst the limits for bacterial counts (100 cfu/ml) and endotoxin (0.25 IU/ml) are based on the European Pharmacopoeia (3) and the European Renal Association Best Practice Guidelines (4). New equipment should be capable of producing ‘ultrapure’ dialysis fluid (bacterial counts <0.1 cfu/ml and endotoxin <0.03 IU/ml) in order to meet the best practice guidelines. Ideally this should be achieved using ultrapure water, however water that meets the minimum standard in Table 1 can be used together with point of use filtration of the dialysis fluid. If routine monitoring demonstrates continuous contamination in excess of the desired levels, a programme to improve this should start immediately. (Good practice)

3.3 A routine testing procedure for water for dialysis should form part of the renal unit policy.

3.4 The dialysate should contain bicarbonate as the buffer.

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4. Haemodialysis membranes

4.1 The balance of evidence supports the use of low flux synthetic and modified cellulose membranes instead of unmodified cellulose membranes. The benefits of low flux synthetic and modified cellulose membranes over unmodified cellulose membranes are limited to advantages arising from different aspects of improved biocompatibility rather than better patient outcomes.

4.2 The balance of evidence supports the use of a dialysis regimen with enhanced removal of middle molecules in incident patients who are predicted to remain on haemodialysis for several years and prevalent patients who have been on haemodialysis for more than 3.7 years. Such patients are at risk of developing symptoms of dialysis-related amyloidosis. Treatments with better clearance of middle molecules include haemodialysis with high flux synthetic membranes and haemodiafiltration. The proven benefits of high flux synthetic membranes in randomized trials are limited to advantages arising from improved biocompatibility and enhanced removal of middle molecules, such as beta-2-microglobulin, rather than better patient survival rates. Chronic high flux dialysis in the HEMO study did not affect the primary outcome of all cause mortality or any of the secondary composite outcome measures including the rates of first cardiac hospitalization or all cause mortality, first infectious hospitalization or all cause mortality, first 15% decrease in serum albumin or all cause mortality, or all non-vascular access-related hospitalizations

4.3 Patients without increased bleeding risk should be given low-dose unfractionated heparin or LMWH during haemodialysis to reduce the risk of clotting of the extracorporeal system. For patients with a risk of bleeding anticoagulation should be avoided or kept to a minimum by using a high blood flow rate and regular flushing of the extracorporeal circuit with saline every 15-30 minutes

4.4 If it is planned to reuse dialysers that are marked ‘for single use only’ the implications of dialyser reuse need to be considered carefully after reading MDA Device Bulletin DB 2000(04) Single-use medical devices: implications and consequences of reuse.

4.5 The use of dialysers sterilized with ethylene oxide should be avoided.

4.6 Haemodialysis patients should not be treated with ACE inhibitor drugs and AN 69 dialyser membranes at the same time.

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5. Haemodialysis dose, frequency and duration

5.1 HD should take place at least three times per week in nearly all patients with end-stage chronic renal failure. Reduction of dialysis frequency to twice per week because of insufficient dialysis facilities is unacceptable.

5.2 Every patient with end-stage chronic renal failure receiving thrice weekly HD should have consistently:

either urea reduction ratio (URR) > 65%
or equilibrated Kt/V of >1.2 (or sp Kt/V of > 1.3) calculated from pre- and post-dialysis urea values, duration of dialysis and weight loss during dialysis.

To achieve a URR above 65% or eKt/V above 1.2 consistently in the vast majority of the haemodialysis population clinicians should aim for a minimum target URR of 70% or minimum eKt/V of 1.4 in individual patients. Aiming for these target doses also addresses the concerns raised by recent data which suggest that women and patients of low body weight may have improved survival rates if the URR is maintained above 70% or eKt/V is at least 1.4.

5.3 The duration of thrice weekly HD in adult patients with minimal residual renal function should not be reduced below 4 hours without careful consideration.

5.4 Patients receiving dialysis twice weekly for reasons of geography should receive a higher sessional dose of dialysis. If this cannot be achieved, then it should be recognised that there is a compromise between the practicalities of dialysis and the patient’s long-term health.

5.5 Measurement of the ‘dose’ or ‘adequacy’ of HD should be performed monthly in all hospital HD patients and may be performed less frequently in home HD patients. All dialysis units should collect and report this data to their regional network and the UK Renal Registry.

5.6 Standardisation of the method of post-dialysis blood sampling is essential since all measurements of dialysis dose require the measurement of the post-dialysis blood urea concentration. Post-dialysis blood samples should be collected either by the stop-dialysate flow method, the slow-flow method or the simplified stop-flow method. The method used should remain consistent within renal units and should be reported to the Registry.

5.7 Patients with acute renal failure should initially receive daily renal replacement therapy. The frequency of renal replacement therapy may be reduced once the metabolic syndrome and fluid status of patients with acute renal failure is stable.

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6. Laboratory and clinical indices of dialysis adequacy other than dialysis dose

6.1 Blood sampling for biochemical and haematological measurements should be performed before a mid-week HD session using a dry needle or syringe.

6.2 Monitoring of pre-dialysis biochemical and haematological parameters should be performed monthly in hospital HD patients and at least 3 monthly in home HD patients.

6.3 Pre-dialysis serum bicarbonate concentrations measured with minimum delay after venepuncture should be between 20 and 26mmol/l.

6.4 Pre-dialysis serum potassium should be between 3.5 and 6.5 mmol/l in HD patients.

6.5 Pre-dialysis serum phosphate should be between 1.1 and 1.8mmol/l.

6.6 Pre-dialysis serum calcium, adjusted for serum albumin, should be within the normal range, preferably below 2.5 mmol/l.

6.7 Pre-dialysis serum albumin corrected calcium x phosphate product should be less than 4.8 mmol²/l².

6.8 Serum PTH levels should be more than twice and less than 4 times the upper limit of normal for the intact PTH assay used. Serum PTH levels do not need to be performed routinely more often than every 3 months

6.9 Serum aluminium concentration should be measured every three months in all patients receiving oral aluminium hydroxide. No patient whose ferritin level is <100 µg/l should have a serum aluminium concentration >60 µg/l (2.2 µmol/l).

6.10 Pre-dialysis haemoglobin concentration should be greater than 10.5-12.5g/dl.

6.11 Data on the frequency of dialysis-related hypotension, defined as an acute symptomatic fall in blood pressure during dialysis requiring immediate intervention to prevent syncope, should be collected and audited.

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7. Vascular access

7.1 To preserve veins for creation of vascular access venepuncture or insertion of peripheral venous cannulae should be avoided in the forearm or arm of all patients with advanced renal failure whenever possible.

7.2 The preferred mode of vascular access for HD patients is a native arteriovenous fistula.

7.3 There should be enough dedicated theatre sessions for access surgery to provide one session per week for every 120 patients on dialysis. With this level of access surgery provision no patient on dialysis, including those patients who present late, should wait more than four weeks for fistula construction.

7.4 Patients should undergo fistula creation between 6 and 12 months before haemodialysis is expected to start to allow time for adequate maturation of the fistula or time for a revision procedure if the fistula fails or is inadequate for use.

7.5 The time to first cannulation of an AVF should be a minimum of 1 month and preferably at least 2 months after creation. First cannulation may be considered between 2 and 4 weeks after creation of an AVF if this is the alternative to insertion of a central venous catheter and a nephrologist or experienced haemodialysis nurse has assessed that the fistula has matured adequately for use for dialysis.

7.6 At least 65% of patients presenting more than three months before initiation of dialysis should start HD with a usable native arteriovenous fistula.

7.7 Investigation of the AVF or graft to assess for evidence of arterial or venous stenoses or access recirculation is required if there is a significant fall in the blood flow rate that can be achieved, a reduction in delivered dialysis dose or a persistent rise in venous pressure in sequential dialysis sessions.

7.8 All patients should be evaluated for a secondary arteriovenous access after each episode of access failure.

7.9 As few HD patients as possible should rely on central venous catheters for vascular access. As an audit measure less than 20% of patients on long-term HD should use tunneled or non-tunneled central venous catheters as the form of vascular access.

7.10 Cuffed, tunneled double-lumen central venous catheters are preferred if temporary vascular access is likely to be needed for more than 3 weeks. Non-cuffed double-lumen catheters may be used if temporary vascular access for haemodialysis is predicted to be required for less than 3 weeks.

7.11 The preferred insertion site for central venous catheters is the internal jugular vein and the catheter should not be placed on the same side as a planned or maturing upper limb arterio-venous access, whenever possible.

7.12 All renal units should use real-time ultrasound to guide insertion of central venous catheters.

7.13 All renal units should have protocols to ensure that full barrier precautions are followed during insertion of temporary and tunneled central venous dialysis catheters.

7.14 All central venous catheter connections and disconnections should be performed under aseptic conditions by trained staff.

7.15 Peripheral and central line blood cultures should be taken prior to starting antibiotics in all cases of suspected catheter-related infection.

7.16 All HD units should collect and audit data on the form of vascular access in use in incident and prevalent haemodialysis patients and the rates of bacteraemia per 1000 patient days using central venous catheters, arterio-venous grafts and arterio-venous fistulae.

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8. Access to and withdrawal from dialysis

8.1 All patients with advanced renal failure (eGFR < 30ml/min), who have a life expectancy of more than 3 months, should be considered for renal replacement therapy and should be referred to a nephrologist.

8.2 If there is no medical contraindication the choice of initial dialysis modality should be based on patient choice.

8.3 After full education and counseling a small proportion of patients may opt for active non-dialytic management of advanced chronic kidney disease, including nutritional, medical and psychological support, rather than plan to initiate dialysis. The numbers of patients not taken on to dialysis and the reasons for this decision should be subject to audit.

8.4 Renal replacement therapy should be commenced when a patient with an eGFR <15ml/min/1.73m² has symptoms or signs of uraemia, fluid overload or malnutrition in spite of medical therapy, and considered carefully when an asymptomatic patient has an eGFR < 6ml/min/1.73m².

8.5 Any decision to discontinue haemodialysis should be made jointly by the patient and the responsible consultant nephrologist after consultation with relatives, the family practitioner and members of the caring team. The decision, and the reasons for it, must be recorded in the patient’s notes. Renal units should develop guidelines for palliative care of such patients, including liaison with community services.

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Summary of audit measures for haemodialysis

The distance and travel time between the patient’s home and the nearest satellite or main haemodialysis unit
The waiting time after arrival before starting dialysis and the waiting time for patient transport after the end of haemodialysis
The proportion of dialysis patients in the main renal unit and its satellite units who are on home haemodialysis
The number of haemodialysis patients and number of haemodialysis stations in the main renal unit and its satellite units expressed per million catchment population
The proportion of patients in the main renal unit and its satellite units who are on twice weekly haemodialysis
Cumulative frequency curves of urea reduction ratio measured using a standard method of post-dialysis sampling
The proportion of patient non-attendances for haemodialysis sessions and the proportion of dialysis sessions shortened at the patient’s request
Cumulative frequency curves of pre-dialysis serum potassium concentration
Cumulative frequency curves of pre-dialysis serum calcium, phosphate calcium x phosphate product and PTH concentrations
Cumulative frequency curves of pre-dialysis haemoglobin concentration
The incidence of symptomatic hypotensive episodes during dialysis sessions
The proportion of prevalent patients on long-term haemodialysis who use an arterio-venous fistula, arterio-venous graft and tunneled or non-tunneled central venous catheters as the mode of vascular access
The number of dedicated renal failure access surgery sessions per 120 dialysis patients
The dates of first referral to nephrology, referral for creation of vascular access and creation of first vascular access and the date and mode of vascular access at the initiation of dialysis should be recorded and audited in all incident chronic haemodialysis patients
The rates of bacteraemia (and specifically the rates of MRSA bacteraemia) observed per 1000 patient days using central venous catheters, arterio-venous grafts and arterio-venous fistulae
The proportion of patients with advanced renal failure (CKD stage 5) who are treated with conservative medical therapy
Record of the serum creatinine, estimated GFR and co-morbidity at initiation of chronic renal replacement therapy (dialysis or transplantation)

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Rationale for clinical practice guidelines for haemodialysis

Introduction

The basis for the management of advanced chronic kidney disease is the seamless integration of renal replacement therapy (HD, peritoneal dialysis, and transplantation) with evidence based medical treatment of its complications. The National Service Framework Part 1: Dialysis and Transplantation has stressed the need for a patient-centred approach in the planning and provision of renal replacement therapy with an emphasis on patient education and choice as well as the provision of adequate resources for elective access surgery, dialysis and transplantation (1). It also identified that a small proportion of patients after counseling may opt for optimal conservative medical therapy without planning to initiate dialysis.

Innovations and changes in HD practice have seldom been underpinned by adequately powered randomised trials. Nevertheless, day-to-day clinical decisions on HD are required and standards need to be set on the best available evidence. Consequently clinical practice guidelines for HD have been developed in Australasia, Canada, Europe and the USA as well as the UK (2-17). These guidelines serve to identify and promote best practice in the delivery of HD and have set clinical standards to allow comparative audit of the key aspects of the HD prescription, laboratory data and patient outcomes. The reports of the UK Renal Registry, Scottish Renal Registry and NHS Quality Improvement Scotland have demonstrated the benefits of performing regular audit to improve clinical standards in HD (2-4).

This module provides an expansion on the 2002 guidelines in HD to incorporate sections on patient-centred HD facilities and initiation of dialysis, an expansion on the section on vascular access and, most importantly, an update on the current guidelines based on evidence from new studies. The USA (NKF-KDOQI) and European (EBPG) guidelines have also been updated recently (9,11,13) and standardisation with these and other international guidelines has been attempted whenever possible. This module promotes the adoption of a range of standardized audit measures in HD and has been designed to permit easy modification on the website to incorporate future changes in practice recommendations based on evidence from new research. The proportions of patients who should achieve clinical and laboratory targets have not been specified for most of the clinical practice guidelines. This approach is designed to allow for greater achievement of audit measures in parallel with improvements in clinical practice.

The National Service Framework for Renal Services Part 1: Dialysis and Transplantation, Department of Health, London, UK, January 2004. (www.doh.gov.uk/nsf/renal/index.htm)

Clinical Standards for Adult Renal Services, NHS Quality Improvement Scotland, March 2003. (www.clinicalstandards.org)

Renal Association Standards & Audit Subcommittee "Treatment of adults & children with renal failure - Standards and audit measures". 3rd Edition, London: Royal College of Physicians 2002. (www.renal.org/Standards/standards.html)

Report of NHS Quality Improvement Scotland (www.nhshealthquality.org)

National Kidney Foundation-K/DOQI Clinical Practice Guidelines for chronic kidney disease: Evaluation, classification and stratification. Am J Kidney Dis 2002; 39: 2 Supplement 1 S1-S266. (www.kidney.org/professionals/kdoqi/guidelines.cfm)

Canadian Society of Nephrology Clinical Practice Guidelines. JASN 1999; 10: Supplement 13 (http://csnscn.ca)

CARI (Caring for Australians with Renal Impairment) Guidelines Part 1 - Dialysis Guidelines. Eds: Knight J and Vimalachandra D, Excerpta Medica Communications, 2000 (www.kidney.org.au/cari/)

National Kidney Foundation-K/DOQI Clinical Practice Guidelines for hemodialysis adequacy, Update 2000. Am J Kidney Dis 2000; 37:1 Supplement 1 S7-S62 (www.kidney.org/professionals/kdoqi/guidelines.cfm)

National Kidney Foundation-K/DOQI Clinical Practice Guidelines and Clinical Practice Recommendations for Haemodialysis Adequacy, 2005 (in press) (www.kidney.org/professionals/kdoqi/guidelines.cfm)

National Kidney Foundation-K/DOQI Clinical Practice Guidelines for vascular access 2000. Am J Kidney Dis 2000; 37: 1 Supplement 1 S137-S180 (www.kidney.org/professionals/kdoqi/guidelines.cfm)

National Kidney Foundation-K/DOQI Clinical Practice Guidelines for vascular access, Update 2005. (in press) (www.kidney.org/professionals/kdoqi/guidelines.cfm)

European Best Practice Guidelines for haemodialysis Part 1. Nephrol Dial Transplant 2002; 17: Supplement 7 S1-S111. (http://ndt.oupjournals.org/content/vol17/suppl_7/index.shtml)

European Best Practice Guidelines for haemodialysis Part 2. Nephrol Dial Transplant 2005;20 (suppl 5) 148-15 (http://ndt.oupjournals.org/content/vol17/suppl_7/index.shtml)

National Kidney Foundation-K/DOQI Clinical Practice Guidelines for bone metabolism and disease in chronic kidney disease. Am J Kidney Dis 2002;39:2 Supplement (www.kidney.org/professionals/kdoqi/guidelines.cfm)

National Kidney Foundation-K/DOQI Clinical Practice Guidelines for managing dyslipidaemias in chronic kidney disease. Am J Kidney Dis 2003; 41: 4 Supplement 3 S1-S92. (www.kidney.org/professionals/kdoqi/guidelines.cfm)

National Kidney Foundation-K/DOQI Clinical Practice Guidelines for nutrition of chronic renal failure. Am J Kidney Dis 2001; 37: 1 Supplement 2 S66-S70. (www.kidney.org/professionals/kdoqi/guidelines.cfm)

National Kidney Foundation-K/DOQI Clinical Practice Guidelines for anaemia of chronic kidney disease. Am J Kidney Dis 2001; 37: 1 Supplement 1 S182-S236. (www.kidney.org/professionals/kdoqi/guidelines.cfm)

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1. Haemodialysis facilities

RATIONALE

1.1 The specification of new or refurbished haemodialysis facilities should adhere to the guidelines that are described in the NHS Estates Health Building Note 53: Volumes 1 & 2. (Good practice)

The specification that is required for a modern haemodialysis (HD) unit has been detailed by NHS Estates and should be followed in all new and refurbished satellite and main renal unit HD facilities (1,2).

1. NHS Estates, Facilities for Renal Services, Health Building Note 53: Volume 1, Satellite dialysis unit & Volume 2, Main renal unit
2. The National Service Framework for Renal Services Part 1: Dialysis and Transplantation, Department of Health, London, UK, January 2004. (www.doh.gov.uk/nsf/renal/index.htm)

1.2 The haemodialysis facility should have sufficient specialist support staff to fulfill the criteria listed by the Renal Workforce Planning Group 2002. (Good practice)

The number of medical, specialist nursing, technical and allied health professionals that are required to provide high quality HD therapy has been standardized by the Renal Workforce Planning Group (1). There should be great emphasis on teamwork, quality assurance and audit, health and safety and continuing professional development for all members of the multidisciplinary team (2).
1. Section 5 Workforce Planning Projections. National Renal Workforce Planning Group Recommendations 2002
2. The National Service Framework for Renal Services Part 1: Dialysis and Transplantation, Department of Health, London, UK, January 2004. (www.doh.gov.uk/nsf/renal/index.htm)

1.3 Except in remote geographical areas the travel time to a haemodialysis facility should be less than 30 minutes or a haemodialysis facility should be located with 25 miles of the patient’s home. In inner city areas travel times over short distances may exceed 30 minutes at peak traffic flow periods during the day. (Good practice)

Equity of access to HD is self evident in a patient-centred service. Lack of local HD provision and the inadequacy of patient transport services are the commonest concerns cited by HD patients and Kidney Patient Associations. The acceptance rate for dialysis declines with increasing distance and travel time from the nearest dialysis unit and patients are less likely to be offered dialysis if the travel time from home to the dialysis unit is more than 37 minutes (1,2). The prevalence rate of HD patients remains significantly lower in the areas of Wales with travel times greater than a 30 minute drive to the nearest current dialysis unit (3). To reverse the inverse relationship between acceptance rates for HD and travel time to the nearest HD facility patients should not need to spend more than 30 minutes traveling to and from dialysis unless they live in a remote geographical area. NHS Quality Improvement Scotland has adopted 30 minutes as the maximum routine travel time to and from HD facilities in Scotland except in remote areas (4) but this guideline may be viewed as impractical in some urban areas because of transport delays due to traffic congestion.

Small satellite units should be established also in rural areas or islands to provide more local access to HD and permit travel distances or times that make thrice weekly HD acceptable to patients. Many of the prevalent HD population are elderly, have diabetes and/or overt cardiovascular disease and have suboptimal vascular access in the form of central venous catheters. Some of these patients therefore may not be medically suitable for treatment at a local satellite HD unit and may need to travel further to a main renal unit for dialysis. A comparison of the costs, quality of dialysis, quality of life and frequency of adverse events of HD in satellite and main renal units in England and Wales showed no major differences except the adequacy of HD, as assessed by measurement of the urea reduction ratio, was better in the patients treated in satellite units (5,6). The provision of dialysis treatment at the 12 renal satellite units in the study potentially saved the HD patients an additional 19 minutes travel time for each dialysis session (5). This study has confirmed that HD in a satellite unit is an effective alternative to treatment in a main renal unit and provides support for a national network of HD facilities with adequate capacity to enable all medically suitable patients to receive chronic HD without having routine travel times in excess of 30 minutes. The location of satellite units should provide maximum geographic access to patients within the local catchment population and a centre of population based approach has been used in the planning of small satellite HD units in some regions of the UK (7).

Better local access to HD can only be achieved if there are improvements in patient transport as well as the development of an extensive network of HD facilities. The Cross Party Group on Kidney Disease Report, 2004 reinforces this point since it identified that 49% of HD patients in Scotland had travel times in excess of 30 minutes even though only 10% patients lived more than a 30 minute drive from the nearest HD facility (8). The development of patient transport services that avoid the need to collect and drop off other patients at the dialysis centre or at other healthcare facilities would help keep travel times to a minimum.

Audit measure 1 - The distance and travel time between the patient’s home and the nearest satellite or main haemodialysis unit

1. Roderick P, Clements S, Stone N et al. What determines geographical variation in rates of acceptance onto renal replacement therapy in England? J Health Service Res Policy 1999; 4:139-146
2. Boyle PJ, Kudlac H, Williams, AJ. Geographical variation in the referral of patients with chronic end-stage renal failure for renal replacement therapy. QJM 1996; 89: 151-157
3. White P, James V, Ansell D et al. Equity of access to dialysis facilities in Wales. QJM 2006; 99:445-452
4. Clinical Standards for Adult Renal Services, NHS Quality Improvement Scotland, March 2003. (www.clinicalstandards.org)
5. Roderick P, Armitage A, Nicholson T et al. A clinical and cost evaluation of haemodialysis in renal satellite units in England and Wales. Am J Kidney Dis 2004; 44: 121-131
6. Roderick P, Nicholson T, Armitage A et al. An evaluation of the costs, effectiveness and quality of renal replacement therapy provision in renal satellite units in England and Wales. Health Technol Assess 7. 2005; 9:1-178MacGregor MS, Campbell J, Bain M et al. Using geographical information systems to plan dialysis facility provision. Nephrol Dial Transplant 2005; 20:1509-1511
8. Cross Party Group on Kidney Disease, April 2004 (www. show.scot.nhs.uk/srr/Publications/Cross party report renal disease in Scotland.pdf)

1.4 Haemodialysis patients who require transport should be collected from home within 30 minutes of the allotted time and be collected to return home within 30 minutes of finishing dialysis. (Good practice)

Patient travel to and from hospital is the main source of complaint of hospital HD patients (1). Reduction in the waiting times before traveling to or from the HD unit would significantly shorten the “dialysis day” for many patients (1). Provision of designated parking adjacent to the dialysis area would encourage patients to organize their own transport to and from dialysis and so reduce the need for hospital provision of patient transport. Specialised, fully funded transport for dialysis patients is the gold standard and should be developed to facilitate timely transport by car or ambulance to meet these guidelines. The provision of dedicated or individualized HD patient transport services, which can avoid the need to collect and drop off other patients, and the use of staggered starting times for HD would help to reduce patient waiting times before starting and after completing dialysis. Audit of this patient-centred index of quality of HD provision has been reported in the Scottish HD population by Quality Improvement Scotland (QIS) (2).

Audit measure 2 - The waiting time after arrival before starting dialysis and the waiting time for patient transport after the end of haemodialysis

1. Clinical Standards for Adult Renal Services, NHS Quality Improvement Scotland, March 2003. (www.clinicalstandards.org)
2. Report of NHS Quality Improvement Scotland (www.nhshealthquality.org)

1.5 All patients who may be suitable for home dialysis should receive full information and education about home haemodialysis. Home haemodialysis training is not available in all renal units and some patients may need to travel to a sub-regional or regional centre to pursue their choice to train for home haemodialysis.(Good practice)

HD may be performed in a variety of settings, including hospital-based units, free-standing units, and in the home. Patient survival and quality of life adjusted for co-morbid risk factors has been reported to be higher on home than hospital HD (1,2). Home HD is more cost-effective than hospital HD if patients remain on dialysis for more than 14 months to offset training and setup costs (3). The choice between home and hospital HD for patients assessed as able to perform dialysis at home should be determined mainly by patient preference rather than economic grounds. Nevertheless the number of patients on home HD in the UK has continued to decline. Not all UK units provide home HD and, based on a review of the clinical-effectiveness and cost-effectiveness of home, satellite and hospital HD, the National Institute of Clinical Excellence (NICE) has recommended that the option to train to perform home HD should be available to all patients (4,5). NICE recommended that more than 10% of dialysis patients should be treated by home HD and, whilst this recommendation is achieved in Australasia (6), very few centres in the UK have more than 5% of dialysis patients on home HD (7). Higher prevalence rates of home HD may be achieved by having a designated home HD training centre serving several renal units within a region akin to current service provision for renal transplantation.

Audit measure 3 - The proportion of dialysis patients in the main renal unit and its satellite units who are on home haemodialysis

1. Woods JD, Stannard D, Blagg CR et al. Comparison of mortality with home hemodialysis and centre hemodialysis: A national study. Kidney Int 1996; 49: 1464- 1470
2. Saner E, Nitsch D, Descourdes C et al. Outcome of home haemodialysis patients: A case-control study. Nephrol Dial Transplant 2005, 20: 604- 610
3. Mackenzie P, Mactier RA. Home haemodialysis in the 1990's. Nephrol Dial Transplant 1998; 13: 1944-1948
4. Mowatt G, Vale L, Perez J et al. Systematic review of the effectiveness and cost-effectiveness and economic evaluation of home versus hospital or satellite haemodialysis for people with end-stage renal failure. Health Technol Assess 2003; 7: 1-174
5. National Institute of Clinical Excellence. Full guidance on home compared with hospital haemodialysis for patients with end-stage renal failure October 2002. (www.nice.org.uk)
6. MacGregor MS, Agar JW, Blagg CR. Home haemodialysis - international trends and variation. Nephrol Dial Transplant 2006; 21: 1934-45
7. The Renal Association UK Renal Registry, The Seventh Annual Report, December 2004. (www.renalreg.com Renal Association Standards & Audit Subcommittee)

1.6 Haemodialysis capacity in satellite and main renal units within a geographical area should increase in step with predicted need. To allow for patient choice regarding out of hours haemodialysis schedules, provision of holiday haemodialysis and expansion in patient numbers calculation of the required number of haemodialysis stations should be based on using each station for 2 patients per day three times per week. The national average number of hospital haemodialysis patients per million catchment population reported for the previous year by the UK Renal Registry should be regarded as the minimum capacity for haemodialysis in each geographically based renal service. Alternatively up-to-date regional data may be used. For example the national average provision for 312 hospital haemodialysis patients (78 stations) per million catchment population in Scotland at the end of 2005 may be regarded as a minimum haemodialysis capacity in all regions in 2006. The level of hospital haemodialysis provision will need to be higher in areas with a high ethnic and/or elderly population and increase nationwide over the next 10 years. (Good Practice)

HD treatment has evolved rapidly since its introduction and HD is the main mode of dialysis in most developed countries. HD was the established mode of dialysis at 90 days in 67.5% of the UK patient cohort in 2003 compared with 59% in 1998 (1). About 40% of patients starting renal replacement therapy (RRT) are referred as late uraemic emergencies with no time for the planning of, or counseling on, the options for dialysis, and such patients are more likely to remain on HD (2,3). HD is also the default therapy for all end stage renal disease (ESRD). Despite the success of transplantation and peritoneal dialysis (PD), HD continues to have the highest rate of growth of all treatment modalities. Many patients are maintained by HD after failure of renal transplants or because they have had to abandon PD. After the first 3 years of dialysis 3% of the 1998-2000 cohort of HD patients in the UK had converted to peritoneal dialysis, mostly within the first year, whereas almost 11% of the PD patients had switched to HD each year (1).

The provision of HD capacity within the UK has tended to lag behind patient demand and this has restricted both patient choice and access to hospital HD (4). UK Registry data from the end of 2004 showed that there were 261 patients per million population on hospital or satellite HD (5). 40.9% of the estimated 638 prevalent end-stage renal failure patients per million population were receiving hospital HD and only 1.2% were on home HD at the end of 2004 (5). Scottish Renal Registry data from the end of 2004 showed that 76% of dialysis patients were receiving hospital HD, 299 patients per million were receiving hospital HD and 725 prevalent patients per million were on chronic RRT (6). At the end of 2005 the Scottish Renal Registry data showed that 77% of dialysis patients were receiving hospital HD, 312 patients per million were receiving hospital HD and 758 prevalent patients per million were on chronic RRT (7). Hospital HD provision in Scotland increased by an average of 18 patients per million population each year between 2000 and 2005. Regional variation in the level of provision of HD within the UK continues and this needs to be addressed to permit equity of access to HD throughout the country (8).

Additional capacity is needed to allow for patient choice of HD schedule, holiday HD and anticipated expansion in patient numbers. For these reasons the calculated number of dialysis stations that are required in each geographical area should be based on using each machine only for two patients per day three days per week. The degree of flexibility in HD capacity and scheduling then depends on the proportion of HD patients who are on a third shift each day. The national average number of hospital HD patients per million catchment population reported for the previous year by the UK Renal Registry may be regarded as the minimum capacity for HD in each geographically based renal service. This approach should drive the provision of HD upwards in the areas with below average HD capacity. For example the provision an average of 312 hospital HD patients (or 78 stations) per million catchment population at the end of 2005 could be regarded as a minimum HD capacity in all regions in 2006. The required capacity for HD will be greater in areas with a high ethnic or elderly population due to their higher prevalence of ESRD and these areas will need proportionately greater HD capacity than the national average. HD capacity will need to expand greatly over the next 10 years as the number of prevalent ESRD patients rises progressively and the proportion of the patients who are elderly and/or have co-morbidity also increases (9). Regional and national audit of HD capacity will highlight if there is inequity of access to HD and provide support for the development of HD facilities in such geographical areas. Meeting the need for HD will be a major challenge and regular audit should be used to raise HD capacity across the UK in step with the projected increase in demand over the next decade.

Audit measure 4 - The number of haemodialysis patients and number of haemodialysis stations in the main renal unit and its satellite units expressed per million catchment population

1. The Renal Association UK Renal Registry, The Seventh Annual Report, December 2004. (www.renalreg.com Renal Association Standards & Audit Subcommittee)
2. Metcalfe W, Khan IH, Prescott GJ et al. Can we improve early mortality in patients receiving renal replacement therapy? Kidney Int 2000; 57: 2539–45
3. Little J, Irwin A, Marshall T et al. Predicting a patient’s choice of dialysis modality: experience in a United Kingdom renal department. Am J Kidney Dis 2001; 37: 981–6
4. Treatment of adults & children with renal failure - Standards and audit measures. 3rd Edition, London: Royal College of Physicians 2002. (www.renal.org/Standards/standards.html)
5. The Renal Association UK Renal Registry, The Eighth Annual Report, December 2005. (www.renalreg.com Renal Association Standards & Audit Subcommittee)
6. Report of the Scottish Renal Registry 2004 (www.show.scot.nhs.uk/srr)
7. Report of the Scottish Renal Registry 2005 (www.show.scot.nhs.uk/srr)
8. Blank L, Peters J, Lumsdon A et al. Regional differences in the provision of adult renal dialysis services in the UK. QJM 2005; 98:183-190
9. Feest TG, Rajamahesh J, Byrne C et al. Trends in adult renal replacement therapy in the UK: 1982-2002. QJM 2005: 98: 21-28

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2. Haemodialysis equipment and disposables

2.1 All equipment used in the delivery and monitoring of therapy should comply with the relevant standards for medical electrical equipment. General safety standards are covered by BS EN 60601-1: 2006 and specific dialysis machine requirements are covered by BS-EN 60601-2-16: 1998 (Medical electrical equipment: Particular requirements for the safety of haemodialysis (HD), haemodiafiltration and haemofiltration equipment. (Good practice)

The equipment used in renal units represents a substantial asset that must be carefully maintained. The selection of equipment should be in accordance with a policy that conforms to the recommendations of the MHRA (MHRA DB2006 (05): - Managing Medical Devices – Guidance for Healthcare & Social Services Organisations – Nov. and National Audit Office (The management of medical equipment in NHS acute trusts in England, National Audit Office, 1999). The above BS-EN 60601-2-16 standard for electrical equipment for renal replacement therapy was defined in 1998, superceded BS5724-2-16:1998 and IEC 60601-2-16:1998 and remains applicable in 2006 (personal communication, Andy Mosson, Association of Renal Technologists).

2.2 Disposables such as dialysers and associated devices are classified as medical devices and should display the CE mark (Good practice)

All disposable equipment such as haemodialysers, blood tubing sets and related devices should display the CE mark. The presence of such a mark signifies compliance with the requirements of the statutory Medical Device Directive and also national and international standards where they exist for new products: BS-EN 1283: 1996 (haemodialysers, haemodiafilters, haemofilters, haemoconcentrators and their extra corporeal circuits), ISO 8638:2004 (Extracorporeal blood circuit for haemodialysers, haemodiafilters and haemofilters) or ISO 13960: 2003 (Plasma filters).

The routine maintenance of the equipment used for renal replacement therapy is essential and the service history of each machine should be documented fully throughout its use-life by the renal unit technicians. Renal units should endeavour to adopt a programme of phased replacement of older HD machines. Although it is possible to keep a dialysis machine operating safely for many years, practical considerations of obsolescence and maintenance costs require a more structured approach. When a particular model of a machine becomes obsolete, companies generally only undertake to supply replacement parts for seven years. Intensive use of HD machines for three 4 hour shifts per day, 6 days per week would complete 26208 hours of use after 7 years. We accept that there is no firm evidence that replacement, as suggested above, is the most cost-effective strategy.

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3. Concentrates and water for haemodialysis

RATIONALE

3.1 Ready made concentrates are classified as medical devices and should display the CE mark. Concentrates that are manufactured ‘in house’ should meet the requirements of BS EN 13867: 2002 (Concentrates for haemodialysis and related therapies). (Good practice)

The presence of the CE mark signifies compliance with the requirements of the statutory Medical Device Directive and also national and international standards where they exist. Dialysis units that manufacture concentrates in-house should ensure that the fluid fulfils the requirements stated in BS EN 13867: 2002 (1).

1. BS EN 13867: 2002 Concentrates for haemodialysis and related therapies (http://www.bsonline.bsi-global.com) Note: A revision of this standard is currently at the Committee Draft stage and should be available by 2008.

3.2 Water used in preparation of dialysis fluid should, as a minimum, meet the requirements stated in Table 1 for chemical and microbiological contaminants. The limits for chemical contaminants are derived from AAMI RD-52 2004 (1), ISO 13959:2002 (2) and the European Pharmacopoeia (3) after consultation within the UK, whilst the limits for bacterial counts (100 cfu/ml) and endotoxin (0.25 IU/ml) are based on the European Pharmacopoeia (3) and the European Renal Association Best Practice Guidelines (4). New equipment should be capable of producing ‘ultrapure’ dialysis fluid (bacterial counts <0.1 cfu/ml and endotoxin <0.03 IU/ml) in order to meet the best practice guidelines. Ideally this should be achieved using ultrapure water, however water that meets the minimum standard in Table 1 can be used together with point of use filtration of the dialysis fluid. If routine monitoring demonstrates continuous contamination in excess programme to improve this should start immediately. (Good practice)

HD exposes the blood of the patient to in excess of 300 litres of water per week through a non-selective membrane, in contrast to an average 12 litres per week through a highly selective membrane (intestinal tract) in healthy individuals. It is essential for the water used to produce dialysis fluid to have appropriate chemical and microbiological purity. Achieving this standard of purity usually requires softening, carbon filtration, reverse osmosis and an effective disinfection programme for the pipework between the treatment plant and the dialysis machines.

The dialysis membrane was regarded as an effective barrier against the passage of bacteria and endotoxin (potent pyrogenic materials arising from the outer layers of bacterial cells) from dialysis fluid to blood. This produced a complacent attitude towards the purity of dialysis fluid. About 10 years ago, several in vitro studies showed that intact membranes used in dialysers are permeable to bacterial contaminants (5-7). The pore size of the membrane appears to be less important than the thickness and the capacity of the membrane to adsorb bacterial products. Consequently low flux (standard) dialysis does not necessarily translate into higher microbiological safety than high flux dialysis or HDF. Patients receiving standard dialysis treatment with low flux cellulose-based membranes (thickness 6–8 microns), may therefore be at greater risk of pyrogenic reactions (see below) than those treated using thicker synthetic membranes which have the capacity to adsorb bacterial endotoxin.

In patients treated with high flux membranes, a risk of pyrogen transfer due to backfiltration (a movement of dialysis fluid into the blood pathway of the device due to an inverted pressure gradient rather than the diffusion gradient discussed above) may exist. Lonneman et al, however, concluded that diffusion rather than convection is the predominant mechanism of transmembrane transport of pyrogens, and backfiltration across pyrogen adsorbing membranes does not necessarily increase their passage (5). It should be emphasised that the adsorption capacity of the synthetic membranes is not infinite and that a breakthrough of pyrogenic substances can occur in the event of excessive water contamination.

A raised C-reactive protein (a sensitive marker of activation of the acute phase response) is associated with a significantly increased risk of death (8, 9), which has led to speculation that impure dialysis fluid may contribute to an increased risk of death in dialysis patients. The use of ultrapure water in a randomized study of 30 incident HD patients was associated with a reduction in CRP levels and a decrease in the rate of loss of residual renal function (10). Impure dialysis fluid has also been implicated in the pathogenesis of dialysis-related amyloidosis (11-13). While this suggestion has not been tested in clinical practice, it would seem prudent to ensure that water is as pure as reasonably possible.

Ultrapure water (< 0.1 cfu/ml and bacterial endotoxins < 0.03 IU/ml) is readily achievable using modern water treatment techniques and should be regarded as the standard for all newly installed water treatment plants (14). The European Best Practice Guidelines recommend the use of ultrapure water for conventional as well as high flux HD (4).

Reinfusion fluid, used in haemofiltration and haemodiafiltration, must be sterile (<1 cfu/1000 litres) and, particularly where large exchange volumes are required, have an endotoxin level of <0.03 IU/ml (15). Even with ultrapure water, this standard of purity can only be achieved with ‘on-line’ fluid production with multiple filtration of the dialysis fluid. Machines designed to produce reinfusion fluid usually require a water supply that meets the microbiological requirements of table 1.

Knowledge of the potentially harmful effects of bacterial products, trace elements and chemicals is still growing, and techniques of water treatment are continuously being developed. The maximum acceptable levels of chemical contaminants in water for dialysis have been established by AAMI (1), ISO 13959 (2) and the European Pharmacopoeia (3). These standards differ in the number and limits of the contaminants specified. Table 1 lists all the contaminants for which a limit is defined for water for dialysis in one or more of the standards. With the exception of nitrate, where the standards differ in their recommendations, the most stringent limit has been adopted. These limits should not be difficult to meet with a correctly specified and maintained water plant. For nitrate, the European Pharmacopoeia specifies a maximum of 2 mg/l nitrate (NO₃) compared to the AAMI standard and ISO 13959 which recommend a limit of 2 mg/l of nitrate as nitrogen (N) which equates to approximately 9 mg/l of NO₃. The more stringent EP limit is often difficult to meet in home HD installations and since the development of the AAMI standard, no new evidence for a lower limit for nitrate has emerged. As the benefits of home HD are well established, the less stringent recommendation has been adopted for nitrate.

Table 1 defines a subset of contaminants that should always be included in routine testing because they occur in relatively high levels and are not restricted in drinking water (chlorine, calcium, magnesium and potassium), or where the drinking water limit (16) is more than five times the recommended limit for water for dialysis. Sodium is included in the ‘mandatory’ group because, although the drinking water limit is 200 mg/l, additional sodium is introduced by softening. Table 1 also defines a group of contaminants for which the drinking water limit is 2 to 5 times the recommended limit for dialysis. In water treated by reverse osmosis, these contaminants will only exceed the limits in table 1 if they occur at relatively high levels in the water supplied to the unit. These contaminants can be omitted from routine tests if data is available to show that the levels in the water supplied to the unit rarely exceed the limit in the table. These data should be obtained from the municipal water supplier, or from tests on the raw water if it is obtained from a private source.

Contaminant	Criteria for inclusion in routine tests	Maximum recommended concentration (mg/l = ppm)	Standards on which limit is based	Initial Test Frequency (if not omitted)
Aluminium	Mandatory	0.01	EP, AAMI, ISO	3 monthly
Calcium	Mandatory	2 (0.05 mmol/l)	EP, AAMI, ISO	3 monthly
Total chlorine	Mandatory	0.1	EP	Not less than weekly
Copper	Mandatory	0.1	AAMI, ISO	3 monthly
Fluoride	Mandatory	0.2	EP, AAMI, ISO	3 monthly
Magnesium	Mandatory	2 (0.08 mmol/l)	EP	3 monthly
Nitrate (as N)	Mandatory	2 (equates to 9 mg/l NO3)	AAMI, ISO	3 monthly
Potassium	Mandatory	2 (0.05 mmol/l)	EP	3 monthly
Sodium	Mandatory	50 (2.2 mmol/l)	EP	3 monthly
Bacteria (TVC)	Mandatory	100 cfu/ml	EP, ISO	Not less than monthly
Endotoxin	Mandatory	0.25 IU/ml	EP	Not less than monthly
Ammonium	Omit if evidence permits	0.2	EP	3 monthly
Arsenic	Omit if evidence permits	0.005	AAMI, ISO	3 monthly
Cadmium	Omit if evidence permits	0.001	AAMI, ISO	3 monthly
Chloride	Omit if evidence permits	50	EP	3 monthly
Chromium	Omit if evidence permits	0.014	AAMI, ISO	3 monthly
Lead	Omit if evidence permits	0.005	AAMI, ISO	3 monthly
Mercury	Omit if evidence permits	0.0002	AAMI, ISO	3 monthly
Sulphate	Omit if evidence permits	50	EP	3 monthly
Barium	Include on indication only	0.1	AAMI, ISO	As indicated
Beryllium	Include on indication only	0.0004	AAMI	As indicated
Silver	Include on indication only	0.005	AAMI, ISO	As indicated
Thallium	Include on indication only	0.002	AAMI	As indicated
Tin	Include on indication only	0.1	ISO	As indicated
Zinc	Include on indication only	0.1	EP, AAMI, ISO	As indicated

Clinical Practice Guidelines

Module 3a - Haemodialysis

Summary of clinical practice guidelines for haemodialysis

1. Haemodialysis facilities

2. Haemodialysis equipment and disposables

3. Concentrates and water for haemodialysis

4. Haemodialysis membranes

5. Haemodialysis dose, frequency and duration

6. Laboratory and clinical indices of dialysis adequacy other than dialysis dose

7. Vascular access

8. Access to and withdrawal from dialysis

Summary of audit measures for haemodialysis

Rationale for clinical practice guidelines for haemodialysis

Introduction

1. Haemodialysis facilities

2. Haemodialysis equipment and disposables

3. Concentrates and water for haemodialysis