Inventors:
Peter S. Colley - Seattle WA
Roy W. Martin - Redmond WA
Assignee:
The Board of Regents of the University of Washington - Seattle WA
International Classification:
A61B 1000
Abstract:
A system for detecting and quantifying air emboli in blood vessels which uses either an intravascular catheter 22 or an esophageal catheter 50. In a preferred embodiment, the intravascular catheter includes an elongated cylindrical tube of flexible material, the tube having a tip 22A and having formed therein an axial aspiration lumen 26 and a second axial lumen 28. An ultrasonic transducer 24, comprising an annular, cylindrical ring of piezoelectric material, is fitted over and secured to the tube adjacent its tip. A microcoaxial cable passes through lumen 28 and is electrically interconnected with the ultrasonic transducer. In a preferred embodiment, the esophageal catheter includes a substantially cylindrical member 54 on which is fitted an ultrasonic transducer 52 comprising an annular, cylindrical ring of piezoelectric material. An elongated tube 58 is secured to the substantially cylindrical member, and a microcoaxial cable 62 passes through tube 58 and the substantially cylindrical member and is electrically connected to the ultrasonic transducer. In use, the intravascular catheter is positioned within a desired blood vessel after percutaneous insertion, and the esophageal catheter is positioned within the esophagus below the bifurcation of the trachea.