Dialysis and Renal Replacement Therapy

Dialysis and renal replacement therapy are the treatments that take over the kidney's filtering role when kidney failure becomes life-threatening. They include hemodialysis, peritoneal dialysis, continuous therapies used in critical care, and kidney transplantation, each of which carries distinctive nursing responsibilities for access care, monitoring, and patient education.

Definition

Renal replacement therapy is any treatment that substitutes for lost kidney function in kidney failure; dialysis achieves this by moving solutes and water across a semipermeable membrane (the artificial membrane of a hemodialyser or the patient's own peritoneum), while kidney transplantation replaces the function with a donor organ.

Scope

This topic orients the reader to the principal modalities of renal replacement, the principle of dialysis that they share, the patient population that depends on them, and the nursing-relevant themes of access, complications, and self-management. It is reference material on the modalities, not a procedure manual or a guide to prescribing dialysis.

Key concepts

• Diffusion and ultrafiltration across a semipermeable membrane
• Hemodialysis
• Peritoneal dialysis
• Continuous renal replacement therapy
• Kidney transplantation as a modality
• Vascular and peritoneal access
• Dialysis adequacy and complications
• Self-management and modality choice

Mechanisms

Dialysis removes accumulated waste and excess water that the failed kidney can no longer clear, relieving the uremic state (Meyer & Hostetter, 2007). In hemodialysis, blood is circulated past a semipermeable membrane against a dialysate so that solutes diffuse down their concentration gradients and excess fluid is removed by ultrafiltration; in peritoneal dialysis the peritoneal membrane serves the same function with dialysate instilled into the abdominal cavity. Continuous therapies apply the same principles more slowly in critically ill patients. Each modality requires reliable access — a vascular access for hemodialysis or a peritoneal catheter — the care of which is a central nursing role (Robinson et al., 2016).

Clinical relevance

Renal replacement therapy sustains a large, long-term patient population, and nurses are closely involved in access surveillance, monitoring during and between treatments, managing complications, and supporting self-care and modality decisions. This entry describes the modalities and their principles as reference knowledge; it does not specify dialysis prescriptions, schedules, or eligibility for any individual, which rest with the treating service.

Epidemiology

Large numbers of people worldwide live with treated end-stage kidney disease, but access to renal replacement therapy, the choice of modality, and outcomes vary widely between and within countries (Robinson et al., 2016). Demand reflects the rising prevalence of chronic kidney disease driven by diabetes, hypertension, and ageing populations (Webster et al., 2017).

History

Practical hemodialysis emerged in the mid-twentieth century and, with the later development of durable vascular access and of peritoneal dialysis and kidney transplantation, turned previously fatal kidney failure into a treatable long-term condition. This created a sustained dialysis population and, with it, the specialised nursing roles of access care and chronic-disease support; nutrition and conservative management remain integral to caring for this group (Kalantar-Zadeh & Fouque, 2017).

Seminal works

• meyer-2007
• robinson-2016

Frequently asked questions

What is the difference between hemodialysis and peritoneal dialysis?

Hemodialysis filters blood outside the body across an artificial membrane in a dialyser, while peritoneal dialysis uses the patient's own peritoneal membrane with dialysate instilled into the abdomen; both rely on the same principles of diffusion and ultrafiltration.

Is kidney transplantation a form of renal replacement therapy?

Yes. Renal replacement therapy includes dialysis and kidney transplantation; transplantation replaces lost kidney function with a donor organ rather than substituting for it mechanically.