Technology Background: Hemodialysis Units

Here's background information on hemodialysis units, outlining the key considerations for making wise purchasing decisions. Learn how the technology is used and which specs are important. Also review ECRI Institute's data describing hospitals' interest in each vendor.

Hemodialysis units replace the main activity of the kidneys in patients with impaired renal function, such as those with end-stage renal disease. They remove large amounts of retained water, metabolic wastes, ions, and organic salts from the blood while it is outside the patient's body. This process restores a reasonable state of health by partially performing renal functions, thereby minimizing further damage to other organs and physiologic systems.

Though fairly mature and widely adopted, the technology continues to evolve. Vendors are taking steps to better link their hemodialysis units to electronic medical records (EMRs) and hospital information systems. In addition, some manufacturers offer variable and programmable systems, which allow individualized patient therapy. And some use removable smart cards with their units, enabling clinicians to download patient treatment data and the treatment protocol for that patient.

Also, smaller, lighter, battery-powered units are being designed that can dialyze almost as effectively as the currently used standard dialysis units described here. Wearable hemodialysis units and implantable artificial kidneys are currently under development.

Furthermore, researchers are working to create more efficient and more biocompatible dialyzer membranes. One technology involves the incorporation of cultured renal tubular cells and glomerular cells layered onto a synthetic membrane to allow hemodialysis units not only to filter toxins and excess fluid out of blood, but also to replace some of the kidney's metabolic and endocrine functions.

The major components of hemodialysis machines are:

1. Extracorporeal blood-delivery circuit—Circulates a portion of the patient's blood through the dialyzer and returns it to the patient.

2. Dialyzer—A disposable component in which...