Device and method for monitoring an extracorporeal blood circuit for the detection of air bubbles

摘要

A device for monitoring an extracorporeal blood circuit of an extracorporeal blood treatment device for detection of air bubbles in blood that is conveyed in the extracorporeal circuit by a blood pump, and a method for monitoring an extracorporeal blood circuit for detection of air bubbles, together with a device for monitoring the extracorporeal blood circuit are described. The device and method are based on monitoring the negative pressure in the extracorporeal blood circuit upstream of the blood pump, to allow differentiation between the occurrence of microbubbles which are attributable to cavitation and an entry of air not due to cavitation. When the negative pressure is above a predetermined limit value and microbubbles are detected in the extracorporeal blood circuit, it is deduced that the microbubbles are produced by cavitation and the mechanisms for dissolving the microbubbles are insufficient to remove the microbubbles again before they could reach the patient.

主权项

1. A device for monitoring an extracorporeal blood circuit in which a blood pump is disposed to convey blood, comprising:
an apparatus adapted to detect an occurrence of air bubbles in blood that flows in the extracorporeal blood circuit, an apparatus adapted to measure a negative pressure in the extracorporeal blood circuit upstream of the blood pump, and a processing unit programmed to deduce a first defective condition when the apparatus adapted to detect the occurrence of air bubbles in the extracorporeal blood circuit detects air bubbles and the measured negative pressure is above a predetermined limit value for the negative pressure, and/or a second defective condition when the apparatus adapted to detect the occurrence of air bubbles in the extracorporeal blood circuit detects air bubbles and the measured negative pressure is below the predetermined limit value for the negative pressure, wherein the first defective condition differs from the second defective condition.