Patent ID: 11938258
Assignee: FRESENIUS MEDICAL CARE HOLDINGS, INC.
Field: Medical technology (Instruments)
Classification: CPC A | IPC A

Claim 0:
1. An extracorporeal blood treatment device comprising:
a dialyzer comprising a blood chamber, a dialysate chamber, a dialysate inlet, a dialysate outlet, and a semipermeable membrane, the blood chamber and the dialysate chamber being divided from one another by the semipermeable membrane;
a dialyzer feed line that leads to the dialysate inlet and is configured to supply dialysate to the dialysate chamber;
a dialyzer discharge line that leads away from the dialysate outlet and is configured to carry dialysate away from the dialysate chamber;
a dialysate pump configured to pump dialysate through the dialyzer feed line to the dialysate chamber and from the dialysate chamber out through the dialyzer discharge line;
a dialysate outlet valve;
a blood pump configured to pump blood through the dialyzer to the blood chamber;
a processor and a sensor in communication with the processor and configured to generate sensor data; and
a balancing device comprising a balancing chamber, a balancing feed line that leads to the balancing chamber and is configured to supply dialysate from a dialysate source into the balancing chamber, a balancing discharge line that leads away from the balancing chamber and is configured to carry dialysate away from the balancing chamber into a drain, wherein
the dialyzer feed line runs from the balancing chamber and is configured to supply dialysate from the balancing chamber to the dialysate chamber, and the dialyzer discharge line leads to the balancing chamber and is configured to supply dialysate from the dialysate chamber into the balancing chamber,
the dialysate pump, the blood pump, or both, are configured to operate in a first operating mode of the extracorporeal blood treatment device and a second operating mode of the extracorporeal blood treatment device,
the first operating mode operates in a configuration wherein the dialysate outlet valve is open such that dialysate flows through the dialyzer feed line, through the dialysate chamber, and into and through the dialyzer discharge line,
the second operating mode operates in a configuration wherein the dialysate outlet valve is closed for a duration of time, dialysate is prevented from flowing through the dialyzer discharge line, and a volume of dialysate passes from the dialysate chamber through the semipermeable membrane and into the blood chamber,
the processor is configured to process the sensor data and to switch the extracorporeal blood treatment device to the second operating mode from the first operating mode, for a time frame, based on the sensor data processed,
the processor is configured to run an initial first operating mode phase for a primary operating time frame, the initial first operating mode phase starting at a beginning of treatment,
the processor is configured to switch the extracorporeal blood treatment device from first operating mode to the second operating mode once the operating time frame expires, and
the processor is programmed to switch from the first operating mode to a second operating mode upon the expiration of a time interval calculated according to Equation I:

Ti=TB·Rn·Qs·Quf·Qb·Xd·Pv·Ptm  Equation I, wherein Ti is the time interval before a backflush, TB is the base time, Rn is the run number coefficient of modification (cm), Qs is the cm based on the substitution fluid rate and whether the substitution fluid is introduced to the blood before the dialyzer or after the dialyzer, Quf is the cm based on the UF rate, Qb is the cm based on the blood flow rate, Xd is the cm based on the type of dialyzer, Pv is the cm based on venous pressure, and Ptm is the cm based on the transmembrane pressure.