Technical Advances in Home Hemodialysis

Various home dialysis systems available for consumer use.

In 1972, when the Medicare Act provided people in the United States with coverage for renal replacement therapy, 40 percent of patients were doing home hemodialysis (HHD). In 2003, only 0.7 percent of the dialysis population in this country were doing HHD. The Aksys Company was founded in January 1991 to develop an HHD machine that would be patient friendly; reduce the labor of setting up, putting on, and tearing down; provide ultrapure water; and reuse the dialyzer and blood tubing to reduce cost. Since then, the following advances in HHD devices have continued to evolve.

The Baxter VIVIA hemodialysis system is designed to deliver high-dose hemodialysis in the home. The machine provides reuse of the dialyzer and blood lines by means of heat disinfection and automatic prime and rinseback; an integrated access disconnect system; an animated, patient-friendly, graphic user interface; wireless connectivity to the clinic; an integrated heparin pump; an integrated water treatment source; and online dialysate generation. The device provides all types of hemodialysis. It is not portable and does not have an integrated blood pressure monitor system. The device received approval from the European Community in December 2013, initially to be used in selected European clinics in 2014, with the ultimate goal of coming to North America in 2015 or 2016.

The 2008K@Home machine, developed from the Fresenius Medical Care 2008 in-center series, was introduced as the Baby K@Home in 2004, withdrawn from the market in 2008, and reintroduced in 2010 with approval from the U.S. Food and Drug Administration (FDA) for home therapy. This machine, which provides all types of hemodialysis, has a standard platform as used in a center, is reliable and easy to maintain, provides ultrapure water, and uses standard supplies. It has automated prime and rinseback, and a blood pressure monitor and a heparin pump are integrated in the device. The dialysate concentration can be adjusted in a manner similar to that used by in-center machines. A patient interface assists patients with setup and interacts with alarms. Remote real-time monitoring is provided by iCare connectivity. WetAlert, a wireless wetness monitor at the needle site, will stop the blood pump if the alarm is activated. The machine is not portable and requires an external water treatment source and significant home remodeling.

NxStage Medical, Inc., was founded in December 1998. The NxStage System One was approved for hemodialysis in July 2003 and for HHD in June 2005. NxStage System One is being used by more than 6000 patients in the United States (i.e., 95 percent of HHD patients in this country) and has performed more than 6 million short daily treatments with low-dialysate-flow hemodialysis at home.

The machine is a cycler (similar to the peritoneal dialysis cycler platform) and has a disposable drop-in cartridge with blood and dialysate lines and dialyzer attached. There is no blood or dialysate interface with the device; thus, disinfection involves removing the disposable cartridge and wiping down the machine. Ultrapure dialysate is provided in sterile 5-L bags, by the Pure Flow system, or by both. The Pure Flow, approved by the FDA in 2008, is a compact, self-contained, disposable deionization water filtration system with a simple faucet or an under-sink connection with a standard electric outlet; thus, it requires no significant home remodeling. The Pure Flow makes a 60-L sack of lactate base dialysate in 7 hours that can be used for as long as 96 hours from the time of preparation. Maintenance of the cycler and Pure Flow is provided through FedEx exchange by the patient of the cycler and Pure Flow components. The device provides short daily low-dialysate-flow hemodialysis five or more times per week. The maximum dialysate flow rate is 200 mL/min. The cycler is portable, weighing 72 pounds. The patient can travel only with sterile bags. There is no integrated heparin pump or automated blood pressure monitor.

The NxStage System One S, approved by the FDA in November 2013, increased the maximum dialysate flow to 300 mL/min, allowing more flexibility in the dialysis prescription. The Nx2me Connected Health, approved by the FDA in October 2013, created a wireless connectivity to the clinic that uses an iPad app for patient entry and transfer of secure patient and treatment data. NxStage is working with the FDA to receive approval for nocturnal HHD.

The PAK Sorbent Hemodialysis System makes use of old technology to provide a portable HHD device that requires only 9 L of tap water per treatment; sorbent technology is used to regenerate the spent dialysate. The REDY (Recirculating Dialysis System) was developed in 1975 and has been used for more than 6 million treatments. This sorbent technology was purchased by Renal Solutions, which developed the Allient machine and had it approved for hemodialysis in June 2005. Renal Solutions was purchased by Fresenius in November 2007, and the intellectual rights of Xcorporeal were purchased by Fresenius in 2009 to facilitate the development of the PAK.

The PAK Sorbent system is designed for traditional, every-other-day and short daily HHD. The machine is separated into two sections, making it portable, and requires no home remodeling. It has a cartridge setup, automated prime and rinseback, touch-screen patient interface, wireless connectivity to the clinic for transmission of treatment and patient data, and a WetAlert similar to the device in the K@Home system, which detects moisture at the needle site. It has no integrated heparin pump or automated blood pressure monitor. The goal is to have the device to market in the United States in 2015 or 2016.

Professor Jules Traeger, MD, developed the concept of the four-cylinder balance chamber technology to push sterile dialysate through the dialyzer, eliminating the proportionate pumps and thus reducing the size of the device to make it portable. This technology was validated with VALEMONT in animal and human trials in 2004 and 2005.

The Physidia S3 device was created from Professor Traeger’s proven concept. The machine is designed for short daily and every-other-day low-dialysate-flow HHD. The balance chamber technology is able to provide hemodiafiltration. The device has a cartridge setup, automated prime, touch-screen patient interface, and the ability to store and transmit treatment data to the clinic in real time or after the treatment. The device is portable and weighs 44 pounds. All dialysate is made in sterile bags and delivered to the patient. It has an integrated automated blood pressure monitor but no integrated heparin pump. Clinical trials continue, and the goal is to have it to market in France in 2015 or 2016.

The Tablo System from Silicon Valley–based HDPlus was designed with smart technology and consumer product simplicity, to significantly improve the patient’s experience and increase the efficiencies of providing dialysis care. This new HHD system was designed with input from dialysis nurses, physicians, and patients currently using HHD. It has single-pass dialysate, a touch-screen patient interface to shorten putting it on and taking it off, alarm interaction, and wireless automatic treatment data transfer. Ultrapure water is produced in real time with Microfluidic Heat Exchange flash pasteurization of incoming tap water and wide-ranging rates of blood and dialysate flow for treatment flexibility. The device is portable and has an integrated water source. Its projected time to market in the United States is unknown.

Quanta SelfCare+ is being developed by Quanta, a company based in Warwickshire, England. Its disposable pumping system, unique to this device, allows it to provide a high-performance hemodialysis system that weighs 64 pounds and is portable. The machine is designed for HHD and in-center self-care, with cartridge setup, automated prime and rinseback, and touch-screen patient interface. It can store and transmit treatment data to the clinic in real time or after the treatment. Standard supplies are used for this machine. The patient can travel only with sterile bags. The machine must have a separate water treatment source for home setup. It has no integrated heparin pump or automated blood pressure monitor. The goal is to market it first in the United Kingdom in 2015 or 2016.

The wearable artificial kidney, whether using blood access or peritoneal access, has unique problems. In February 2014, the FDA approved the start of the first human clinical trials in the United States for the wearable artificial kidney, designed by Blood Purification Technologies, Inc., based in Beverly Hills, California. The results of this trial will be critical in the advancement of this device in the United States.