Casette for use with an i.v. infusion controller

Abstract

A casette employing a stretchable elastomeric membrane used with an intravenous infusion controller to limit the field flow to a patient. The casette includes two sections of rigid plastic fused together with the membrane between them. The membrane and one section of the plastic form the channel through which the intravenous solution passes. The other section of plastic limits the expansion of the membrane to a predetermined size in order to provide the casette with a chamber of known volume. A valving configuration in the inlet and outlet to the chamber controls the fluid flowing through the casette and, thus, to the patient. Each valve includes a section of the elastomeric membrane in proximity to a configured portion of the piece of plastic forming the channel with the membrane. To close the valve, the controller extends a shaped elongated member through the other section of plastic to stretch the membrane and force it into contact with the configured plastic. Alternately opening and closing the inlet and the outlet ports at appropriate time intervals limit the fluid that can pass through the casette. The plastic forming the chamber with the membrane may also include a groove to allow the passage of fluid through the casette when outside the controller. Small circular grooves allow for the removal of air bubbles in the chamber when first priming it for use with the intravenous solution.