Abstract: Apparatus and a method for monitoring a percentage of the oxygen saturation in the hemoglobin of blood flowing through a blood vessel. An optical sensor that detects the percentage oxygen saturation in blood is disposed proximate a proximal end of the catheter. A thermistor is disposed adjacent to the distal end of the catheter and it is employed to detect changes in blood temperature that indicate the position of the catheter's distal end in the blood vessel. Indicia or marks visible at intervals on the outer surface of the catheter enable a medical practitioner to determine the length of the catheter that has been introduced into the blood vessel. A strain relief that is flexible and resists stretching extends along the length of the catheter. For flushing the distal end of the catheter, a fluid supply may be connected to a lumen running through the catheter to provide the flushing fluid.

Abstract: A pressure monitoring apparatus for use in monitoring a physiological fluid pressure in successive patients. Three embodiments of the pressure monitoring apparatus (10, 100, 200) are disclosed, each of which include a disposable portion ( 12, 12', 12") and a reusable portion ( 14, 14', 14"). Fluid flows through the disposable portion and into a cavity (48) that is covered with an elastomeric membrane (46, 46'). When the disposable portion is engaged with the reusable portion, the elastomeric membrane is in contact with a corresponding elastomeric membrane (50, 50'), which covers a pressure sensing cavity (52). A pressure transducer (56) is mounted in the pressure sensing cavity, and the pressure sensing cavity is filled with a fluid and is in fluid communication with a reservoir(38) when not engaged with the disposable portion.

Abstract: A calibration system and method for calibrating a medical sensor (16) that monitors chemical blood gases. A calibrator (12) is used in connection with a tray (14) in which the medical sensor is stored in a sterile environment, both before and during the calibration process. The medical sensor is immersed in a liquid (30) in a tonometry chamber (28) defined in the tray and covered by a membrane (120/122) that is permeable to gas, but impermeable to bacteria. During the calibration process, the tray is inserted into the calibrator, bringing a heated platen (26) into contact with the tonometry chamber, so that the liquid can be heated to a calibration temperature substantially equal to the temperature at which the medical sensor will subsequently be used. A first calibration gas is then bubbled through the liquid until a saturated condition is achieved.

Abstract: An optical distribution system incorporating an improved luminescent based optical fiber sensor incorporating a signal generating component for generating a first optical signal, a signal separating component for delivering said first optical signal to the sensor, delivering said second returned optical signal to an associated signal detector, and including signal interference means to separate said first and second signals and minimize cross-talk therebetween. A sensor optical fiber connects a sensor tip to the signal separating component. The signal detector receives a returned signal from the signal separating component and transmits it to a signal-measuring component of the distribution system.

Abstract: An improved armboard includes receptacles for receiving and holding a medical device to be used in conjunction with the treatment of a patient. The patient's forearm is immobilized on the armboard, a sensor associated with the medical device is inserted into the patient, with a side channel of the armboard holding the medical device and a cable extending from the sensor to a fiber optic connector received in a modular unit stored in a suitable cavity and optical cable channels extending from opposite ends thereof are appropriately sized to prevent misinsertion of the modular unit into the armboard. The armboard is formed from polystyrene foam, and thus is lightweight, disposable after a single use, and the cavities provided therein are appropriately sized to receive and retain the components of the medical device associated therewith.

Abstract: A device for storing and delivering a sensor through a catheter. A sensor delivery device (10, 10') includes an elongate tube (20), which is attached to a rigid housing (22, 22'). A sensor (12), stored within a sterile environment comprising an interior of the sensor delivery device, has an attached signal line (16) that extends along the longitudinal axis of the delivery device and through its proximal end. The proximal end is open when the sensor is in its stored position. An eversible sheath (34) extends between the rigid housing and the signal line, sealingly separating the sterile environment (48) in which the sensor is stored from the open end of the rigid housing. To use the sensor, the signal line is moved into the rigid housing, causing the eversible sheath to turn inside out as the sensor is advanced through the catheter into its use position. The protection afforded by the eversible sheath permits the sensor to be withdrawn through the catheter and then reinserted without introducing contamination.

Abstract: A fiber optic connector in which first and second optical fibers are aligned at a fiber interface of the connector. The first optical fiber has a beveled angle end face, and the second optical fiber has a complementary beveled angle end face. Abutting connector members are joined in a connector enclosure which enables the respective fiber end faces to abut at an angle at the fiber interface. The respective fiber end faces are joined at a vertical aligned position for the connector, also at a horizontal aligned position for the connector. Suitable alignment means provided on the connector members enable alignment of the fiber end faces at the fiber interface. In a fixed aligned position of the assembled connector, the respective fiber end faces are held in abutting and full engagement at the fiber interface, in which the vertical aligned position of the optical fibers in the connector is coincident with the horizontal aligned position thereof.

Abstract: Support apparatus for a fiber optic cable assembly which includes optical fibers having end faces, high tensile strength fibers contiguous with and generally parallel to the optical fibers, and one or more electrical conductors. A main body portion of the apparatus supports the fiber optic cable assembly and includes a central channel and posts therein, for first supporting the cable assembly, then separating the optical fibers from the high tensile strength elements and the electrical conductor, and then aligning the optical fibers on the apparatus so as to precisely position the respective end faces thereof at an outer end of the main body portion of the apparatus.

Abstract: A O.sub.2 /CO.sub.2 /pH compound gas probe comprising a single optical waveguide and a method for making the same. The optical waveguide carries light signals at different wavelengths for monitoring oxygen concentration, carbon dioxide concentration, and pH levels. The probe is designed so that light signals used to monitor carbon dioxide concentration are optically prevented from impinging on the sensor used to monitor the pH level.

Abstract: A device for storing and delivering a sensor through a catheter. A sensor delivery device (10, 10') includes an elongate tube (20), which is attached to a rigid housing (22,22'). A sensor (12), stored within a sterile environment comprising an interior of the sensor delivery device, has an attached signal line (16) that extends along the longitudinal axis of the delivery device and through its proximal end. The proximal end is open when the sensor is in its stored position. An eversible sheath (34) extends between the rigid housing and the signal line, sealingly separating the sterile environment (48) in which the sensor is stored from the open end of the rigid housing. To use the sensor, the signal line is moved into the rigid housing, causing the eversible sheath to turn inside out as the sensor is advanced through the catheter into its use position. The projection afforded by the eversible sheath permits the sensor to be withdrawn through the catheter and then reinsertd without introducing contamination.

Abstract: A CO.sub.2 /O.sub.2 or pH/O.sub.2 gas sensor comprising a single optical fiber and a method for making the same. The optical fiber carries light signals at different wavelengths for monitoring either CO.sub.2 concentration or pH level, in combination with O.sub.2 concentration. Attached to the distal end of the fiber-optic probe is a cylindrical pellet that has one surface covered by a light reflective material (gold foil) and the other surface attached adjacent to the distal end of the optical fiber. Depending on whether the sensor is to monitor either CO.sub.2 or pH, the pellet comprises either a CO.sub.2 analyte indicator molecule or a pH analyte indicator molecule covalently bonded to a polymer matrix material. Also adjacent to the distal end of the optical fiber is disposed a second polymer matrix material which is codissolved with an O.sub.2 analyte reactive indicator molecule.

Abstract: A method for aligning first and second optical fibers of a fiber optic connector at a fiber interface wherein the first optical fiber has a beveled angle end face and the second optical fiber a complementary beveled angle end face, the method including the step of abutting the respective fiber end faces at an angle at the interface, cooperatively engaging a vertical reference surface associated with the first optical fiber with a vertical reference nodule associated with the second optical fiber to align the respective fiber end faces at a vertical aligned position for the connector. Respective horizontal reference surfaces associated with the first optical fiber are also cooperatively engaged with a horizontal reference node and a compressible crush rib associated with the second optical fiber to align the respective fiber end faces at a horizontal aligned position for the connector.

Abstract: A process for flushing clots from an intravascular probe including the steps of positioning a catheter assembly in a blood vessel and then delivering a flushant through the catheter and past the probe at two rates. The flushant is first delivered at a continual rate to maintain the catheter substantially free of blood clots. Periodically, a pulse of flushant is delivered at a second flow rate that is higher than the continual rate that is effective to clear the probe of incipient clots. The hydrodynamic clot flushing system includes a cather insertable within an arterial or venous blood vessel, the cather having an internal axial bore for conducting fluid and in which a probe is slidably received. A valve delivers a flushant through the internal axial bore of the catheter and around the probe at two selected rates.