A dialysis machine is a complex piece of equipment built for a very demanding task. Behind this complexity, you will very often find Schweinfurt – a small city in central Germany that is home to the largest production facility for dialysis machines in the world. And it is here that the hallmark of Fresenius Medical Care – its expertise – can be found, even in the smallest detail.
When a customer of Fresenius Medical Care places an order for a dialysis machine, a sales employee enters the desired
configuration data into a computer. Each region of the world has its own preferences and practices, and therapies must be precisely tailored to patients’ needs. Going by the customer’s requests, the sales employee selects individual settings and modules by mouse click, from the right voltage and plug for the country to software in the local language. Every day, large numbers of these virtual order forms arrive at the Fresenius Medical Care plant in Schweinfurt. Thus begins the life of every second dialysis machine in the world.
Schweinfurt, early in the morning. The factory floor is bathed in light. We gaze out over a sea of dialysis machines, lined up in their dozens at the various production points. From a distance, they almost seem like robots at rest, while busy people work all around them. Yet it’s noticeably quiet. People have been hard at work here since 5 a.m., when flextime starts. Many of the more than 1,000 employees at the plant like to get an early start to their day. Some of them are working hard at assembly benches lined up in rows, pulling white plastic tubes through a perforated panel. Tubing is everywhere.
What looks to the uninitiated like a confusing tangle is actually a clear layout which an expert instantly recognizes, like a tailor reading a pattern. “This is the hydraulic system for our 4008 series,” plant manager Dr. Christoph Sahm says. “We make it in 50 different versions, depending on customer requirements.” The people who work here have all these variants in their heads. “After about two years, you’ve built every version we make at least once,” says one of the assemblers. Sometimes you simply need this level of expertise.
TUBING TO BE TRUSTED The proper attachment of tubing is anything but a trivial matter. The safety and reliability of dialysis treatment depends on these tubes and on the pumps and valves they are connected up with. During just one treatment session, up to 120 liters of blood are pumped through a filter, known as the dialyzer. The dialyzer is attached to the outside of the machine, and is connected by tubes to both the patient’s circulatory system and to the machine. During treatment, the patient’s entire blood supply flows through the dialyzer several times. At the same time, the dialysis machine prepares dialysis solution from ultra-pure water and a concentrate, and pumps it in the opposite direction through the dialyzer, where it picks up the substances filtered out of the blood.
Each minute, about half a liter of dialysis solution passes through the dialysis machine to remove from the blood the filtrate substances and excess water which, due to kidney insufficiency, the patient cannot excrete in urine like healthy people can. The dialysis solution flows through the many meters of tubing and passes through valves and pumps in precisely controlled amounts.
All these minutely adjusted components must work reliably, even on their one-millionth use. These machines often remain in service for a decade or more. This demands a great deal from the machines – and from the people who develop and produce them. Here again, the expertise at the Schweinfurt plant plays an important role.
OF BALANCES AND BUDGETS Bearing proud witness to this expertise is a glass case right next to the entrance. Plant manager Christoph Sahm always stops here when he is giving visitors guided tours of the facility. The showcase holds the first generations of various dialysis machine components, each a pioneering achievement of Schweinfurt dialysis technology. By comparison with their successors from this state-of-the-art production facility, they almost seem antique. Among the items on display are two dark red concave plastic discs. Sahm picks them up. “This was one of our first balancing chambers. It is now over 30 years old,” he says. “And it’s still a key component, even in our latest dialysis machines. Over the years, we have continually developed it, and we still manufacture it ourselves.” Sahm also explains the origin of the name “balancing chamber”. “It’s a module that regulates the volume of fluid moving through the machine. It balances the amount of fresh dialysis solution flowing through the dialyzer and picking up harmful substances in the blood with the amount of used dialysis solution. Put simply, the balancing chamber makes sure that the right amount of dialysis solution is pumped to the filter and back to the dialysis machine – for the right ‘balance’ after treatment.”