Continuous Renal Replacement Therapy Machines

Continuous renal replacement therapy (CRRT) is used to treat patients suffering from acute kidney injury (AKI), a critical condition characterized by sudden temporary loss of normal kidney function. CRRT machines replace impaired renal function continuously over an extended period of time (e.g., 24 hours a day for several days) until the kidneys can resume their usual function. They do this by removing blood from the patient, filtering it to remove excess fluid and metabolic wastes as the kidney would, and returning the blood to the patient. Typically used on critically ill patients, CRRT machines are usually found in the intensive care setting.

CRRT has come a long way from the early days when therapy was delivered without blood pumps (e.g., simply relying on the patient’s heart to drive the blood through the extracorporeal circuit). Even so, today’s technology leaves much room for improvement. While human factors design has progressed, future designs need to incorporate better alarm management and more intelligent and/or responsive algorithms for measuring and reporting fluid administration and/or ultrafiltrate removal from the patient.

In this Evaluation, we tested two pumps from two suppliers: B. Braun’s Diapact and Gambro’s Prismaflex. Our Evaluation focuses on three main criteria: performance, alarm management, and human factors design.

We also provide judgment and key selection factors for the remaining CRRT devices on the U.S. market: Edwards Lifesciences’ Aquarius (distributed by Baxter Healthcare in the United States), Fresenius’s 2008K, and NxStage’s System One.

ECRI Institute recommends that users carefully consider each of the products in this Evaluation, regardless of whether we tested its performance. We also strongly recommend prepurchase trials to determine whether the CRRT machines under consideration are appropriate for your facility’s intended use and typical blood and therapy-fluid flow rates (e.g., pediatric low-flow applications, high-flow treatments for septic patients). In addition to conducting the prepurchase trial, you should carefully assess your workflow processes and your clinical needs and preferences, along with the machine’s capabilities, specifications, and costs, when making a purchasing decision.

Both the Diapact and the Prismaflex are rated Acceptable. Each product has different strengths and weaknesses.

The Diapact is an older-generation CRRT machine that provides average capabilities and features but has only limited capacity for upgrades to enhance its flexibility or functionality. It offers excellent fluid balance accuracy that never exceeded a ±4% error during testing (falling well within our criterion of ±10%). It can provide slow continuous ultrafiltration (SCUF), continuous venovenous hemodialysis (CVVHD), and continuous venovenous hemofiltration (CVVH) with administration of replacement fluid predilution or postdilution. (See the glossary for a list of common abbreviations. )

However, the Diapact has several key drawbacks: It has poor human factors design, its labeling is not intuitive, and although its alarm management is adequate, we would prefer that it provide more detailed and descriptive onscreen messages regarding possible causes of an alarm and/or methods to address the alarm. It also cannot provide replacement-fluid flow rates above 6,000 mL/hr, which are typically used for high-flow-rate treatment of septic patients. And the machine can be operated without tubing in the blood leak detector; although a scenario in...