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D. K. Hothi and C. P. Schmitt

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 etting Up a Paediatric Home HD
S
Program
Patient Selection Criteria
The reasons for selecting a HHD treatment can
be multiple, including medical, social, education
or families exercising their rights to choose a unit
where HHD is an option. At the earlier stages of
a HHD program, it is advisable to set conservative selection criteria until the team’s experiences
and confidence grows. A suggested patient selection criteria are listed in Table 23.2, but the specifics should be determined in the planning stage
of a home HD program by a multidisciplinary
team.
With growing confidence and experiences, the
team at Great Ormond Street Hospital has gradually moved away from a lengthy list of inclusion
criteria to a few exclusion criteria that mainly
comprise (i) a lack of a home or home base to
accommodate the dialysis treatment and (ii) lack
of commitment to deliver the agreed dialysis
schedule reliably and consistently. Failed home
PD does not necessarily preclude the possibility
of HHD.

Table 23.2  Key selection criteria for paediatric home
HD
Patient and family commitment to delivering the
dialysis schedule consistently at home
Patient cut-off weight determined by home dialysis

system
Well-functioning vascular access
Absence of or controlled psychosocial concerns
Sufficient room within the family home to
accommodate the dialysis equipment and 1-month
supply of dialysis consumables
If reverse osmosis dialysis system required,
permission and ability to modify the home water
source
Adequate family household hygiene that does not
increase the patient’s risk of infection
Family home is not located in an area with frequent
and prolonged electricity supply disruptions or an
emergency source of power is not available at all times
Patient is medically stable despite clinical
manifestations of multi-disease or multi-organ
involvement

Infrastructure
Developing a HHD program requires careful
planning, resources, a commitment to safety and
risk management and dedicated staff. The service
delivery model can vary considerably and is
largely influenced by four factors:
• Resources and existing expertise
–– Is the ambition to be fully independent or
will a partnership with a neighbouring paediatric or adult service become necessary?
• Spectrum of dialysis prescriptions to be
offered
–– Will routine prescriptions include daytime

and nocturnal treatments?
–– How many sessions will be routinely prescribed per week?
• Preferred dialysis system
–– What home modifications will be required?
–– How familiar is the in-centre dialysis team
with the home dialysis system?
–– Which dialysis consumables will be delivered to the home and how often?
–– How will the dialysis machines and dialysate system be serviced and maintained?
• Training patients and their carers
–– Will training take place on the dialysis unit
or within a dedicated facility?
–– Is a training program available or will it
need to be designed?

Finances and Business Case
A dialysis team wishing to develop a program
will need to prepare a robust business case for the
hospital board or executive team. A key requirement of a business case is a risk-benefit analysis.
Geary et al. have explored the cost of delivering HHD in children and reported a 27% saving
after comparing the cost of delivering a HD treatment at home compared to a dialysis unit [12].
Cost saving was largely from removing the cost
of the hospital bed and dialysis staff. The latter is
particularly relevant in paediatrics owing to the
recommended 1:1 or 1:2 nurse-to-patient ratio
when delivering HD treatments in hospital. To


23  Home Haemodialysis in Children

establish the potential cost savings for a HHD

program, each unit needs to predict the projected
size of the program and multiply that by an accurate cost-saving calculation when patients transition home. This financial ‘gain’ must then be
offset against the cost pressures of delivering a
home HD program. These include:
• Staffing the multidisciplinary team required to
deliver the program
• Lease, rental or purchase of dialysis machines
alongside service and maintenance costs
• Home conversions or modifications to accommodate the dialysis systems
• Dialysis consumables and drugs cost which
will be proportionally higher as the prescribed
weekly treatment frequency often increases
• Establishing and maintaining a training
facility
• The resultant and unintended bed vacancies as
in-centre patients transition home
In adult programs the potential savings from a
home dialysis program can be significant as the
HD patient pool may be in the hundreds and thousands. In comparison the size of paediatric HD
programs typically range from 4 to 25 patients.
Thus, the potential cost benefit of a paediatric
HHD program will depend on the number of children that transition home and in real terms will be
small. In comparison, the financial risk and investment to establish a HHD program is significant
and probably higher than adult programs owing to
the larger multidisciplinary team requirement.
Thus, in the first few years the financial risk to
benefit analysis of a paediatric HHD program will
feature risk dominance as the program attempts to
establish itself and gain momentum. Further difficulties of convincing policy makers and insurance companies may arise from the fact that for
the majority of children HD is a short-term bridging therapy to transplantation. It is estimated that

HHD with a home conversion only becomes more
cost-effective than in-centre HD when patients
remain on treatment for more than 14  months
[13]. In Europe median waiting time for deceased
donor kidney transplantation in Europe is still
about 15 months [14].

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If one was to broaden the financial case of
paediatric HHD to the health economics related
to the life of a patient, the narrative should be
more favourable. Children on HHD should typically have improved health outcomes and thus a
lower medical burden. Access to school and
education has the potential to improve future
career prospects and the subsequent financial
contribution to society. Truth to be told, similar
to many paediatric case studies, building a
population-­
based financial case for HHD is
challenging and less convincing than the emotive case around the potential gain for an individual child.

Safety
HHD in children remains a relatively new therapy that places a high-risk clinical procedure
directly under the care of patients and their families within their homes. Therefore, safety should
be the central focus point of any program design
with mitigations in place to minimise the potential to cause harm. The greatest sources of risk
fall under four broad categories.

Vascular Access

Children can be dialysed at home through a central venous line or preferably an arteriovenous
fistula (AVF). Whilst training for home dialysis,
families need to develop an understanding of the
common complications related to the vascular
access and the appropriate response. Central line
malfunction and infection risk are attenuated
with weekly alteplase locks [15]. At minimum,
weekly dressing changes are recommended with
monthly surveillance for exit site infections.
Patients with fistulae are advised to check them at
minimum daily. For buttonhole needling, we
encourage needling by the same person, to promote good health of the fistula. At Great Ormond
Street Hospital, where possible we actively promote older children or young adults to become
the primary person who needles their fistulae.
Any major change in blood flow rates and system
pressures should be reported to the centre. We
suggest functional ultrasound surveillance of the


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fistulae every 3  months for early and timely
detection of issues.

Anticoagulation
Clotting in an HD circuit can affect the quality
and quantity of dialysis provided. Children at
home can use unfractionated heparin (UFH),
often as an initial bolus dose and then a continuous infusion [16] in line with in-centre prescribing
practices.

Alternatively,
a
low-molecular-weight heparin (LMWH) can be
prescribed. Lutkin et al. have reported their experience using dalteparin, a LMWH, for children
on home HD. Each child was started on a single
intravenous dose of 50 IU/kg through the arterial
arm of the dialysis circuit within 15 minutes of
the treatment starting. The dose was increased if
clots were repeatedly visible in the circuit and
dialyser and reduced if there was any evidence of
bleeding events or prolonged bleeding from an
AVF in children dialysed in this way. The dalteparin dose was routinely increased if a child was
moving from daytime to nocturnal home HD. The
median dalteparin dose at 12-month follow-up
was 40 IU/kg (range 8–142 IU/kg). Factors associated with higher dalteparin dosing requirements included a younger age of the child
(p < 0.01), a lower blood flow rate (p < 0.01) and
the use of a central venous line for dialysis access
(p = 0.038). No children had evidence of bioaccumulation of dalteparin or inadequate clearance.
No significant bleeding or adverse events were
reported [17]. Therefore, for children on augmented HHD prescriptions, both UFH and
LMWH are feasible options.
 amily Centric Remote Monitoring
F
and Support
The motivation to dialyse at home will differ
amongst families as will the perceived risks and
sources of stress. In the 1970s paediatric HHD
was replaced by in-centre dialysis largely due to
carer burden. Families reported feeling lonely
and struggling to cope with the medical and technical responsibilities [18]. This is not too dissimilar today. Therefore, it is absolutely essential to

be proactive in creating an individualised risk

D. K. Hothi and C. P. Schmitt

management and support system for all families
dialysing at home to minimise their perceived
carer burden as much as possible whilst maximising the family’s positive experiences of dialysing
at home. The key components of this are:
• A home assessment prior to committing to a
home therapy to assess the suitability of the
home environment for dialysis and to align
child and family expectations of HHD.
• Access to clinical and technical support 24/7,
especially if families are dialysing in the evenings after school or overnight.
• Written guidelines for the family describing
normal ranges for dialysis parameters including BP, HR, temperature, UF rates and venous
pressures, with clear instructions on how and
when to seek help if parameters fall out of the
normal range.
Remote monitoring is not universally
employed, but if available can alleviate family
anxieties. A growing plethora of telehealth platforms is making it feasible for the exchange of
treatment data real time between families and
their medical teams. This is another source of
reassurance that also provides the opportunity for
the medical team to intervene earlier and make
adjustments to treatments outside the hospital
clinic reviews. Currently haemodialysis machines
are not equipped with digital telecommunication
devices. Internet-based online functions may be

applied, but require careful consideration of reliability and data safety. For further detail, please
refer to the Chap. 18 on Remote Patient
Monitoring.
Dialysing overnight introduces additional
risks and induces anxiety both in caregivers and
children due to the potential risk of needle dislocation with AV fistulas and AV grafts, central
line disconnection or not hearing machine alarms
whilst everybody is sleeping. It is recommended
to address these additional measures. In our
experience at Great Ormond Street Hospital, a
simple and familiar device such as a baby monitor can be a useful strategy to amplify the sound
of the alarms overnight. Monitoring for


23  Home Haemodialysis in Children

a­ ccess-­related blood leaks is essential and can be
effectively achieved through enuresis alarm
pads; more sophisticated monitors such as
HEMOdialert™ that are sensitive to fluid and
the colour red are now available. For the
NxStage™ system, a cycler base fluid detector is
available to detect any circuit water leaks.

Effective Training and Education
Program
Training programs can vary considerably
between teams and are important for aligning
expectations. Ideally it is advisable to train two
people from the outset and involve the child or

adolescent as much as age appropriate. Families
should be offered repeated opportunities to
enhance their knowledge and skills once they
are home especially following (1) an adverse
event such as a central line infection, (2) a
change in treatment or (3) a change in dialysis
access such as switching from central lines to
fistulae.
Companies supplying the dialysis equipment
often provide considerable teaching materials
and expertise. However, in paediatrics adaptation
is often necessary. To ensure families have totally
understood the content, a trainee’s competency
should be formally assessed and signed off both
by the trainee and trainer. Prior to discharge an
adherence contact signed by the child and their
carers can be extremely important at formalising
and thus reinforcing the decision taken by the
medical team and family to delegate responsibility for providing the dialysis treatment to the
family within their home; any deviation will be
taken very seriously.
Training can take place in the HD unit or
within a separate training facility. Ideally, prior to
going home, families should have the option to
‘step down’ within an environment co-located
within hospital grounds but separate from the
dialysis unit, in order to simulate the home environment as much as possible. Following discharge, it is advisable for one of the HHD nurses
to be present for the first dialysis treatment in the
patient’s home. This provides reassurance and
also provides the opportunity to coordinate and

connect the family with their community teams.

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Regular, four to six weekly outpatient visits are
recommended for detailed history, physical
examination and biochemical work-up.

Staffing
In order to provide safe, effective care, a HHD program needs to be staffed by a skilled multidisciplinary team. The composition of the team can
vary depending on resources and whether you are
operationally independent. At minimum access to
or recruitment of a HD nurse, nephrologist, dietician, dialysis technician, pharmacist and social
worker is necessary. Collaborating with other
allied health professionals such as a psychologist,
community nurses, local paediatricians and general practitioners is desirable for optimal support.
Families at home will be expected to communicate with a number of professionals, but to
ensure their safety and trust, clear communication pathways need to be developed and explicitly laid out to the families. It is important to
establish a reliable communication channel
between the core HHD team and the families for
assurance that all is well. As families become
more confident at home, communication with the
hospital team can become less frequent, but it is
important to invest in maintaining that contact.

Dialysis Equipment
 ialysis Systems Requiring Home
D
Water Conversions
The majority of commercially available HD

machines that are suitable for paediatric HHD
require home water conversions to produce the
large volumes of high-quality dialysate necessary
for the dialysis treatment. This cost can sometimes become a barrier for transitioning children
to HHD, especially when it is a bridging therapy
for a renal transplant. Water conversions can also
be a source of additional work and anxiety for
families as complications such as leaks and
blocked drains can occur and need to be addressed
as a matter of urgency. Dialysate fluid needs to be
tested on a regular basis.


396

Water conversion requires the installation of a
cold water outlet and a drain to allow the carbon
filter, reverse osmosis unit and dialysis machine
to be fitted.
• A system for testing the water quality needs to
be put in place.
• Typically, families test their water for chloride
every session.
• In addition, they bring a sample for advanced
testing to their monthly hospital clinic visit.
The dialysis technician will test for chemicals,
endotoxins and microbiology.

 obile HD System: NxStage™
M

The NxStage System One™ is a portable home
dialysis machine that functions without home
water modifications. Dialysate is prepared from
ordinary tap water in batches of up to 60 litres
using the NxStage PureFlow™ SL integrated
water purification and dialysate production system. Water is mixed with sterile-filtered concentrate, to produce lactate-buffered dialysate.
Premixed bagged dialysate is also available for
home patients in sterile, 5 L bags, with a variety
of fluid configurations.

D. K. Hothi and C. P. Schmitt

per session and thus the spent dialysate is highly
saturated. The prescribed dose is altered by
adjusting the ‘flow fraction’ which is the ratio of
effluent flow (spent dialysate plus ultrafiltration)
divided by blood flow rate and corresponds to the
degree of dialysate saturation. Compared to the
more conventional machines that are also used in
centre, the NxStage™ system offers some advantages in the home setting. It takes 30–40 minutes
to set up from start to finish, with the option to
partially set up the machine for convenience.
Owing to the freedom from home conversions,
families are mobile and thus able to transport the
dialysis machine and consumables between family homes and on holiday. The machine has been
designed to be used by patients; whilst its simplicity means that additional technical capabilities are absent, in the home environment in the
hands of patients this can be an advantage.

Adult Home HD Experience

Experience with HHD is substantially greater in
adults. Data on clinical outcomes and patient
experiences amongst adults is increasing. We can
learn from this experience as we build our paedi• Three different NxStage™ circuits have been atric experience.
used at Great Ormond Street London: CAR-­
Adults on augmented home dialysis regimes
172-­
C is the standard circuit with a pre-­ have demonstrated several health benefits, and
attached
polysulfone
dialyser.
The the effect is the most pronounced with nocturnal
extracorporeal circuit volume is 163 mls.
prescriptions. Patients switching to short-daily
• CAR-124-C, a modified CVVH circuit with 33% survived at 6  years and demonstrated
an extracorporeal volume of 97  mls (minus reduced hospitalisation [19], fewer vascular
dialyser) that can house any appropriately access problems, reduced antihypertensive medisized dialyser.
cation burden, lower incidence of left ventricular
• CAR-125-B, with an extracorporeal circuit hypertrophy, improved anaemia control and a
volume minus the dialyser of 55 mls to treat reduction in the use of phosphate binders as a
children weighing 10 kg and above.
consequence of the improved phosphorus clearance [20]. Nocturnal HD is associated with sigPrescribing dialysis treatment using the nificant reduction in the risk for mortality or
NxStage™ system is different from standard HD major morbid events when compared to convenprescriptions with respect to the volume of dialy- tional HD. During a matched cohort study comsate utilised during each dialysis session. In con- paring survival between nocturnal HHD and
ventional HD dialysate, volumes of 200–500 mls/ deceased and living donor kidney transplantaminute are typically prescribed. In comparison, tion, there was no difference in the adjusted surduring treatment with the NxStage™ system, vival between nocturnal HHD and deceased
dialysate volumes are typically less than 60 litres donor renal transplantation. The proportion of


23  Home Haemodialysis in Children

deaths amongst the three was 14.7% for nocturnal HHD, 14.3% for deceased donor transplantation and 8.5% for live donor transplantation [21].

This is very reassuring for patients who are not
eligible for transplantation or those waiting for a
transplant.
On a more granular level, patients on nocturnal HHD demonstrate improved cardiovascular
outcomes with superior blood pressure control;
regression of left ventricular hypertrophy,
improvement in left ventricular systolic function
and ejection fraction; an overall improvement in
haemodynamic status; a more responsive
endothelial-­mediated vasodilation; an improvement in lower extremity peripheral arterial disease [22, 23]; and a slowing in the rate of
calcification progression [24]. Potential biochemical benefits include normalisation of the
blood urea, serum creatinine, albumin, B2 microglobulin, homocysteine and triglyceride levels
and other nutritional markers. Patients have a
lower medication burden with a reduced dependency on antihypertensives, freedom from phosphate binders, reduced iron supplementation [22]
and a lower dose and occasionally discontinuation of erythropoietin [25]. Quality of life is
improved owing to removal of fluid and dietary
restrictions, the capacity for full-time employment and for women the ability to become pregnant and deliver healthy babies. Despite receiving
treatment overnight, patients report an improved
quality of life and sleep patterns and a resolution
of sleep apnoea [22]. In a comparison with peritoneal dialysis, patients reported a similar perception of control over their kidney disease and
did not consider home HD as a more intrusive
treatment [26].
Despite the positive narrative, a number of
concerns remain. Firstly, dialysis equates to the
non-selective, measured and unmeasured removal
of solutes, minerals and trace elements from the
blood compartment. Thus, unknowingly or unintentionally dialysis may cause deficiencies, the
so-called dialysis deficiency syndrome. This has
already received the attention of dieticians supporting vulnerable groups such as pregnant
women and children. Secondly, owing to the

increased requirement for needling fistulae or

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accessing central lines during augmented HD
prescriptions, there have been concerns that both
the frequency and the home setting may cause
additional access-related complications. The
results however are conflicting, and causality to
the home setting is difficult to prove, as both frequency and expertise are likely to be confounders
applicable to the home and hospital setting.
Finally, concerns remain over the burden placed
on carers for patients dialysing at home. Reports
have repeatedly highlighted the cognitive burden
carers perceive from taking on the responsibility
for a complex treatment normally delivered by
nurses and doctors in hospital on their loved
ones. This concern is real and cannot be obliterated, but steps can be taken to both monitor and
reduce the cumulative impact. Successful interventions include respite care or spreading the
burden by training multiple people to deliver the
treatment at home.

Paediatric Home HD Experience
Literature on paediatric home HD is scarce and
limited to experiences from a handful of specialist centres worldwide. Reassuringly the results
are similar to the larger adult literature.
Simonsen et al. were the first to describe their
experience of HHD in four children, age
10–19 years, who were treated with slow nocturnal HD for 7–8 hours, six nights each week, for a
period of 5–55 months. Achieving a weekly Kt/V

of 7.2–13.6, these children had no fluid or dietary
restrictions, but actually required phosphate supplements orally to avoid hypophosphatemia.
Catch-up growth was achieved and quality of life
improved markedly [27].
Geary et al. reported on six patients on nocturnal HHD aged 11–17 years. The first two patients
were transitioned to an augmented home program after all previous dialysis options had
failed. The following four patients had requested
HHD. One patient switched to a hybrid program
comprised of three consecutive days of home
nocturnal HD combined with one in-centre
4-hour HD session per week after 1 year of dialysing exclusively at home. No dropouts from the