Alternate Hemodialysis Prescriptions in Children

What Is the Optimal Dialysis Dose?

In the Hemodialysis (HEMO) Study comparing high-dose HD versus standard-dose HD, the relative risk of death was 0.96. In a secondary analysis, the HD dose showed a significant correlation with body mass index (BMI) and mortality. This raised the possibility of a survival advantage from increasing HD dose in low-BMI patients such as children.

The Dialysis Outcomes and Practical Pattern Study (DOPPS) review of 22,000 adult HD patients from seven countries found that a higher dialysis dose was an independent predictor of lower mortality on HD with a synergistic survival advantage with treatment time. Therefore, survival was most pronounced by combining a higher Kt/V with a longer treatment time, such that for every 30 minutes longer on HD, the relative risk of mortality was reduced by 7%. An Australian and New Zealand Dialysis and Transplantation (ANZDATA) analysis of 4193 patients found that the optimal dialysis dose for survival was a Kt/V greater than or equal to 1.3 and a dialysis session greater than or equal to 4.5 hours.

Such research set the scene for “quotidian” dialysis programs, namely a move away from conventional 4-hour, three-times-per-week dialysis to more frequent or more prolonged dialysis sessions, on the whole, located at home.

Adult Quotidian Hemodialysis Experience

The adult literature on quotidian dialysis practices is consistently positive. Compared with conventional dialysis, increasing frequency, time, or convective clearance is beneficial to the patient. For patients switching to short-daily HD, 33% survived at 6 years and demonstrated reduced hospitalization, fewer vascular access problems, reduced antihypertensive medication burden, lower incidence of left ventricular hypertrophy, improved anemia control, and a reduction in the use of phosphate binders as a consequence of the improved phosphorous clearance.

Nocturnal HD offers superiority over all other quotidian dialysis regimens. It is associated with a significant reduction in the risk for mortality or major morbid events compared with conventional HD. During a matched cohort study comparing survival between nocturnal HD and deceased and living donor kidney transplantation, there was no difference in the adjusted survival between nocturnal HD and deceased donor renal transplantation. The proportion of deaths among the three was 14.7% for nocturnal HD, 14.3% for deceased donor transplantation, and 8.5% for live donor transplantation. This is very reassuring for patients who are not eligible for transplantation or those waiting for a transplant. In a comparison with peritoneal dialysis (PD), patients reported a similar perception of control over their kidney disease and did not consider home HD as a more intrusive treatment.

Some adult units wishing to build on the success of extended HD prescriptions at home have started a wider range of in-hospital HD prescriptions. Graham-Brown et al. have shown improved plasma phosphate levels, left ventricle (LV) mass and favorable LV remodeling, reduction in dialysis-related symptoms, and sleep quality in adults on thrice-weekly, nocturnal HD, in-center compared to adult patients on conventional HD.

Pediatric Quotidian Hemodialysis Experience

Literature on pediatric quotidian HD is scarce and largely single-center home HD experiences. In-center quotidian prescriptions are often short-term, forming a bridging therapy to home HD. Available results are similar to adult data and include pertinent pediatric-specific metrics, such as growth.

Tom et al. demonstrated improved growth in children without the requirement for growth hormone by dialyzing for 5 hours, three times per week, to yield a single pool Kt/V of 2.0 in combination with a caloric intake at 150% of the recommended daily allowance for age. Goldstein et al. delivered six-times-weekly HD at home using the NxStage system in four patients for 16 weeks. All of the children demonstrated progressive reductions in blood pressure (BP) load with concomitant discontinuation of antihypertensive medications in two patients. Serum phosphate levels improved without changes in phosphorus binder medication requirement.

Simonsen et al. first described the outcomes for nocturnal HD in four children aged 10 to 19 years who were treated with HD for 7 to 8 hours, 6 nights each week, for a period of 5 to 55 months. Achieving a weekly Kt/V of 7.2 to 13.6, these children had no fluid or dietary restrictions and required phosphate supplements to avoid hypophosphatemia. Catch-up growth was achieved, and quality of life improved markedly. Subsequently, Geary et al. reported on six children aged 11 to 17 years on nocturnal home HD. One patient developed a fistula aneurysm from repeated use in the absence of steal syndrome, and no line disconnections were reported. BP control was variable, with two patients with native kidneys still requiring antihypertensives, and three patients became hypotensive, requiring prophylactic midodrine to support their BP during ultrafiltration (UF). All patients were completely free from fluid and dietary restrictions, phosphate binders were discontinued, and all patients required supplementation with phosphate in the dialysate in combination with a higher calcium dialysate to prevent a net negative calcium balance. Appetite, well-being, school attendance, and physical and psychological health-related quality of life scores improved in all patients. However, caregivers' feedback did highlight the perceived “burden” of dialyzing at home. Many reflected on the increased intensity of workload that necessitated establishing a new routine within the home. The additional responsibilities evoked anxiety. The mother of one patient was psychologically and emotionally worn out after 1 year and moved to a hybrid program when the patient refused to revert back to in-center dialysis.

Perhaps one of the most exciting promises of extended home HD prescriptions is the ability to influence the outcomes and prognosis of a child positively. We describe the case of a 10-year-old with presumed severe, irreversible cardiomyopathy whose cardiac function normalized after 6 months of extended home HD.

Infrastructure

In a cost analysis of daily home nocturnal HD compared with conventional in-center HD, a 27% saving was seen for each patient dialyzed at home despite the increased “disposable” costs of more frequent dialysis sessions. However, this needs to be balanced against the resource commitment of providing safe and effective home therapy. It requires careful planning, resources, dedicated staff, and an appreciation of risk and governance issues. Programs need to decide on the type of dialysis offered, for example, nocturnal versus short daily treatments, long daily treatments, or hybrid prescriptions. They also need to decide on the type of dialysis machine and water source.