Patent ID: 6974438

Claim:
A device for detecting malfunction of a gravity fed intravenous delivery system that includes a fluid reservoir, a fluid flow-rate valve, and tubing for delivery of the fluid from the container to a catheter, the catheter being inserted intravenously in a patient, the device comprising: (a) a conduit body including: (i) a housing configured for interconnection with the tubing, fluid flowing through an interior flow passage in said housing, said housing including at least one pressure release passage to allow the fluid to pass between said interior passage and a pressure-sensing region; and (ii) an elastic non-permeable sheath deployed so as to circumscribe said housing such that said pressure-sensing region is located between an exterior wall of said housing and said sheath, wherein said sheath is configured such that, when a fluid pressure within said interior flow passage is less than atmospheric pressure, said sheath is pressed against said housing and, when a fluid pressure within said interior flow passage rises above atmospheric pressure, said sheath expands; (b) a sensing mechanism deployed around said conduit body, said sensing mechanism including at least one sensor configured to discern the expansion of said sheath; and (c) an indication system coupled to said sensor.