Nephrology clinical outcomes

Clinical outcomes are broadly agreed, measurable changes in health or quality of life that result from our care. Constant review of our clinical outcomes establishes standards against which to continuously improve all aspects of our practice.

About the Nephrology Service

The Renal Unit at Great Ormond Street Hospital (GOSH) provides a comprehensive diagnostic and treatment service for children with diseases affecting the kidneys. It is the largest unit in the UK. Each year there are approximately 300–350 admissions to the renal ward, 100 admissions to outlying wards, over 7,000 outpatient attendances, 30 new renal transplants, and 70 patients on dialysis (a treatment that helps to remove toxins from the blood and helps maintain salt and water balance).

The renal team provides expert care for a number of general kidney conditions and rare, very specialist conditions such as congenital renal anomalies; nephrotic syndrome; hypertension, renovascular disease and vasculitis; and tubular, metabolic and stone disorders. In addition, we support a number of District General Hospitals by running joint outreach clinics with their local teams.

Our service is unique in the fact that we have the first fully established home haemodialysis programme for children in the UK. Dialysis is a life-saving treatment necessary for children whose kidneys have failed.

We have strong links with the UCL Institute of Child Health, our overall mission being to improve the diagnosis, treatment and prognosis of children with kidney and urinary tract diseases through high-quality basic science and clinical research. There are extensive laboratory facilities for molecular and cellular biology within the unit, and strong links to affiliated laboratories.

Clinical outcome measures

Summary:

1. Renal transplant recipient mortality

2. Renal transplant survival

3. Peritoneal dialysis

4. Home dialysis

5. Vascular access for haemodialysis

1. Renal transplant recipient mortality

The best (gold standard) therapy for children with severe irreversible kidney failure (end-stage kidney disease) is kidney transplantation. Internationally, the best outcomes are achieved if the kidney is donated by living donors who are related to the child (as opposed to deceased donors) and if transplantation occurs before the child requires kidney replacement therapy with dialysis.

This is not always possible as some patients require surgery to have their kidneys removed prior to transplantation. Others may present suddenly with end-stage kidney disease and we have no option but to initiate dialysis therapy to stabilise them, as it takes up to six months to prepare for transplantation. Many children will have other conditions that occur alongside their kidney failure. These are called co-morbidities and can pose medical and surgical problems when looking after children with kidney transplants. The renal team at GOSH receive a number of referrals from national and international centres for complex patients requiring kidney transplantation. These patients tend to be at higher risk and are associated with increased morbidity and mortality risks. We record the survival of both children themselves (patient survival) as well as their kidney transplant (renal allograft survival). 

1.1 One year patient survival in children receiving renal transplants

Definition

Percentage of paediatric patients aged between 1 and 18 years undergoing a renal transplant who were alive at one year after transplantation.

In these charts, we compare our results against the combined results from the other nine paediatric transplant centres in the UK for the years 2012 to 2014. 

 
 

1.2 Five year patient survival in children receiving renal transplants

Definition

Percentage of paediatric patients aged between 1 and 18 years undergoing a renal transplant who were alive at five years after transplantation.

In these charts, we compare our results against the combined results from the other nine paediatric transplant centres in the UK for the years 2012 to 2014.

 
 

2. Renal transplant survival

In addition to the survival of the children themselves (patient survival), we continuously monitor the kidney transplant or renal allograft survival rate. If the transplant does not survive, the child will need to be recommenced on dialysis.

2.1 One year kidney transplant (renal allograft) survival in children receiving renal transplants

Definition

Percentage of paediatric patients between 1 and 18 years undergoing a renal transplant who were alive with a functioning kidney transplant (not requiring dialysis) at one year after transplantation.

In these charts, we are compare our results against the combined results from the other nine paediatric transplant centres in the UK for the years 2012 to 2014. 

 
 

2.2 Five year kidney transplant (renal allograft) survival in children receiving renal transplants

Definition

Percentage of paediatric patients aged between 1 and 18 years undergoing a renal transplant who were alive with a functioning kidney transplant (not requiring dialysis) at five years after transplantation.

In these charts, we compare our results against the combined results from the other nine paediatric transplant centres in the UK for the years 2012 to 2014. 

 
 

3. Peritoneal Dialysis

Children with renal failure have a number of factors that in combination can have a negative impact on growth. For example, children report feeling nauseated and many vomit frequently; their taste sensation is altered; their blood hormone levels that influence appetite and growth are abnormal; and they often have strict fluid and dietary restrictions limiting access to foods they enjoy. Peritoneal dialysis treats children with kidney failure by removing toxins and excess water.

One of the key objectives of the service is to actively monitor a child’s height and weight, utilising the expertise of a renal dietician to intervene early to optimise the growth potential. Here at GOSH, we consider that for the vast majority of children, nutritional intake has the greatest potential to influence growth (through maximising calories from the foods children eat, providing additional supplements to drinks, or using nasogastric tubes or gastrostomies). This has to be balanced against the possibility of introducing excessive calories and causing obesity. In contrast, many centres internationally use growth hormone injections to promote growth with a smaller emphasis on nutrition.

We report our weight, BMI (body mass index) and growth data to an international registry that compares the height and weight standard deviation of 100 Paediatric Peritoneal Centres worldwide. The BMI gives us a surrogate marker of obesity. The standard deviation score (SDS) tells us how different the patient’s measurement is against population averages. For example, a height SDS value of 0 means that the patient’s height is the same as the population average. The more positive a number, the taller the patient is compared to population averages and the more negative the number, the shorter the patient is compared to population averages.

3.1 Height standard deviation score

Definition

For paediatric patients aged between 1 and 18 years, who are treated with peritoneal dialysis, we calculated the height SDS when they began peritoneal dialysis and at the time of reporting to the registry at the end of 2012 and at the end of 2014. This is compared with the combined results from approximately 2,000 patients from 100 centres in 38 countries. 

 

The children at GOSH starting peritoneal dialysis are taller than children across the world. At GOSH, we maintain this height advantage after the children start peritoneal dialysis.

3.2 BMI standard deviation score

Definition

For paediatric patients aged between 1 and 18 years, who are treated with peritoneal dialysis, we calculated the BMI SDS when they began peritoneal dialysis and at the time of reporting to the registry at the end of 2012 and at the end of 2014. This is compared with the combined results from approximately 2,000 patients from 100 centres in 38 countries.

 
BMI standard deviation score for children receiving peritoneal dialysis 2014

3.3  Feed supplementation

Definition

For paediatric patients aged between 1 and 18 years who are treated with peritoneal dialysis, we report the number of patients on food supplements at the end of each year. The figures below are for 2014. This is compared with the combined results from approximately 2,000 patients from 100 centres in 38 countries.

A significantly higher percentage of peritoneal dialysis patients at GOSH are on nutritional supplements than those treated elsewhere in the world.

4. Home dialysis

All groups representing the renal community, such as NICE, the Renal Association, and the Government, are recommending home dialysis. That is, either peritoneal dialysis (PD), which is delivered at home, or home haemodialysis (HD), in preference to in-centre dialysis. This is particularly important for children because there are only 10 dedicated paediatric haemodialysis units in England and therefore some children have to travel up to three hours to get to hospital, three times per week for their haemodialysis treatment. As a consequence, they cannot attend school full-time and their social and family time is severely disrupted. Therefore, we at GOSH firmly believe that wherever possible children should be dialysed at home.

There has been a growing trend towards home HD internationally. This has been partly driven by the increasing demand on in-centre dialysis beds, but also by research that indicates superior clinical outcomes compared with all other dialysis modalities.

When selecting between PD and HD, many factors need to be considered. As a rule of thumb, home PD is the treatment of choice in babies and infants. In older children and adults, home HD may be the preferred option.

4.1 Dialysis modality

Definition

For paediatric dialysis patients aged between 0 and 18 years, we report the number of children on in-centre HD, PD, and home HD. 

To date, we are the only paediatric dialysis unit in Europe offering home HD using a mobile dialysis machine: the NxStage™. This machine is specifically designed for home use and is thus more user-friendly. It is a mobile system that does not require a home water conversion to supply dialysate. Instead, it uses pre-prepared, ultrapure dialysate bags. This allows children to travel between homes and, importantly, offers opportunities for holidays.

Input from psychology, social work and family therapy services is integral to the support provided to families preparing for home HD.

This chart shows that Great Ormond Street Hospital’s home HD provision has increased year-on-year since 2010.

4.2 Home dialysis

Definition

For paediatric patients aged between 0 and 18 years, who are on long-term dialysis, we report the percentage of children on home dialysis (peritoneal dialysis and home HD).

In most adult centres, only a small percentage of patients are on home dialysis – in-centre HD dominates. In paediatric centres, home dialysis figures are better as babies and infants typically start on PD.

Here at GOSH, we offer both home PD and HD and therefore the percentage of our patients on home dialysis therapies exceeds 50 per cent. The drop in the percentage of children on home dialysis in 2012 was due to a larger proportion of infants on HD than in previous years and equipment restrictions that meant children weighing less than 20kg could not be offered the NxStage dialysis machine.

Adaptations in late 2012 have addressed these restrictions for children up to 12kg, and the percentage of children on home dialysis for 2013 and 2014 is more than 50 per cent.

5. Vascular access for haemodialysis

Good vascular access is essential for haemodialysis. With children, we have two options, a tunnelled, central venous catheter or 'line' (CVC/CVL) or a surgically formed arteriovenous fistula (AVF). Internationally, there is a consensus opinion that AVF is the ‘gold standard’ approach for haemodialysis access. However, despite our good intentions AVF is not always possible for children. The smaller blood vessels pose technical surgical challenges and are associated with a higher primary failure rate, namely that the fistula doesn’t work. Fistulae have to be needled before each dialysis session. In practical terms, this equates to two needles, at least three times per week. Understandably, for the vast majority of children, an active desensitisation and educational programme is necessary for them to even consider and then accept an AVF as a realistic option.

5.1 Paediatric haemodialysis patients with functioning AVF

Definition

For paediatric haemodialysis patients between 1 and 18 years, we report the number of patients with a functioning AVF and a CVL.

At GOSH, we take a proactive approach to fistulae. Since 2009, the number of patients with fistulae has been rising. In 2012, the numbers appear to fall marginally, but this reflects the larger proportion of babies and infants on HD in 2012 compared with the previous years.

Our greatest success to date has been successfully creating and needling a fistula in a three-year-old child. This reflects the dedication and commitment from our multi-professional team including surgeons, medical staff, play therapists and the psychosocial team.

This information was published in July 2016, and will be updated annually.