Intravenous liquid administration by pump - with external pressure sensing cartridge regulating discharge pressure

摘要

A pump for delivering an intravenous liquid to a patient includes an integral sensor for detecting the pressure of the outlet stream. The outlet passes through a disposable cartridge which has a diaphragm responsive to the liquid pressure. This cartridge is retained by detents within a cavity in the pump housing so that the diaphragm movement activates a plunger rod. The plunger rod is spring-loaded and operates a pivoted lever. When the pressure in the cartridge exceeds a predetermined value the lever causes a light beam to be broken. This stops the pump until the normal operating pressure is attained. The apparatus delivers an intravenous liquid at a controlled pressure.