Method of delivering liquid to a patient via a disposable pumping cassette having a flow control & pressure monitoring member

摘要

A disposable pumping cassette having an integral auxiliary flow control and pressure monitoring member is used for delivering a medicinal fluid to a patient. The pumping cassette includes an elastomeric member mounted in a rigid body having an inlet and an outlet. An inlet valve and an outlet valve on the cassette are opened, and the flow control is positioned to allow the medicinal fluid to flow freely through the cassette, priming it before the outlet is connected to the patient. The cassette is then coupled to an associated pump driver, closing the flow control to disable free fluid flow through the cassette, and the outlet of the cassette is coupled in fluid communication with the patient's body. The medicinal fluid is drawn into a pumping chamber formed in the rigid body as a plunger of the associated pump driver is drawn up from the elastomeric membrane at a recess formed in the rigid body. The plunger is then advanced downwardly, forcing the elastomeric membrane into the pumping chamber to deliver the medicinal fluid to the patient. The pressure of the fluid delivered to the patient is monitored through contact of the auxiliary flow control member with the elastomeric membrane over an outlet channel of the cassette.