Abstract: A plurality of flow sensors are fabricated on a single substrate. The substrate is laid out to provide the proper physical relationship of the individual sensors. The resulting multiple sensor structure may be effectively used as respiration detector by positioning a different sensor element at each of the airflow orifices (i.e., two nostrils and mouth) of a patient. In the preferred embodiment, the sensors are thermoresistive elements, which are screened on the substrate using conductive ink. The change in temperature of the air flow in relation to the ambient at each orifice provides an indication of the flow and may be used to determine the extent of the flow. The substrate is packaged in a single piece adhesive strip which provides ease of proper attachment by the patient.

Abstract: A fiber-optic data-link used to interface a remote process variable sensor/transmitter to a local process control system includes a local light source module and a remote interface module interconnected by one or more optical fibers. Energy for operating the remote interface module and its associated process variable sensor/transmitter is provided by light energy transmitted from the local site to the remote site and converted at the remote site to an electrical signal. The local light source module and the remote interface module each may include a microcontroller.

Abstract: An apparatus for and method of monitoring respiration of a patient using impedance changes of the body to indicate respiration events. Cardiac related artifacts are suppressed by separately processing an EKG signal. Transient artifacts are accommodated by modifying the pass band of the respiration monitoring circuitry to selectively attenuate the signal within the frequency range of the transient artifact.

Abstract: A breathing sensor comprising a thin flexible compliant film transducer exhibiting piezoelectric and pyroelectric properties. The transducer preferably comprises a thin film of polyvinylidene fluoride (PVDF) having a pattern of metallization on the opposed surfaces thereof defining electrodes. The transducer is designed to be affixed proximate a person's airway such that the tidal flow of inspired and expired air will impinge upon the transducer. It is adapted to be coupled to electronic circuitry for indicating normal breathing, for providing an alarm in the event of sleep apnea and for providing an indication when sound related to respiratory distress is present.

Abstract: A plurality of flow sensors are fabricated on a single substrate. The substrate is laid out to provide the proper physical relationship of the individual sensors. The resulting multiple sensor structure may be effectively used as a respiration detector by positioning a different sensor element at each of the airflow orifices (i.e., two nostrils and mouth) of a patient. In the preferred embodiment, the sensors are thermoresistive elements, which are screened on the substrate using conductive ink. The change in temperature of the air flow in relation to the ambient at each orifice provides an indication of the flow and may be used to determine the extent of the flow. The substrate is packaged in a single piece adhesive strip which provides ease of proper attachment by the patient.

Abstract: A RF ablation catheter for removing athero-stenotic lesions or modifying the tissue characteristics of the interior walls of selected blood vessels is described. The catheter is characterized in having a tip member which during the initial placement of the catheter within the vascular system so that the distal tip member is disposed in a working relation with the lesion to be removed, means are provided for increasing the cross-sectional profile of the tip members to thereby cause it to move into engagement with the lesion to be excised. The application of an RF voltage across a pair of bipolar electrodes is used to create an electric arc for effecting the cutting action, or alternatively, just sufficient RF energy to sear or otherwise alter the tissue surfaces engaged by the distal tip member.

Abstract: A RF ablation catheter for removing athero-stenotic lesions or modifying the tissue characteristics of the interior walls of selected blood vessels is described. The catheter has a distal tip member which is disposed in a working relation with the lesion to be removed during the initial placement of the catheter within the vascular system. Means are provided for increasing the cross-sectional profile of the tip member to thereby cause it to move into engagement with the lesion to be excised. The application of an RF voltage across a pair of bipolar electrodes is used to create an electric arc for effecting the cutting action, or alternatively, just sufficient RF energy to sear or otherwise alter the tissue surfaces engaged by the distal tip member.

Abstract: A RF ablation catheter for removing athero-stenotic lesions or modifying the tissue characteristics of the interior walls of selected blood vessels is described. The catheter is characterized in having a tip member which during the initial placement of the catheter within the vascular system so that the distal tip member is disposed in a working relation with the lesion to be removed, means are provided for increasing the cross-sectional profile of the tip members to thereby cause it to move into engagement with the lesion to be excised. The application of an RF voltage across a pair of bipolar electrodes is used to create an electric arc for effecting the cutting action, or alternatively, just sufficient RF energy to sear or otherwise alter the tissue surfaces engaged by the distal tip member.

Abstract: A RF ablation catheter for removing athero-stenotic lesions or modifying the tissue characteristics of the interior walls of selected blood vessels is described. The catheter is characterized in having a tip member which during the initial placement of the catheter within the vascular system so that the distal tip member is disposed in a working relation with the lesion to be removed, means are provided for increasing the cross-sectional profile of the tip members to thereby cause it to move into engagement with the lesion to be excised. The application of an RF voltage across a pair of bipolar electrodes is used to create an electric arc for effecting the cutting action, or alternatively, just sufficient RF energy to sear or otherwise alter the tissue surfaces engaged by the distal tip member.

Abstract: A surgical cutting blade for use in an electrosurgical scalpel includes a thin flat ceramic substrate having a rounded tip where the edge portion of the substrate on the opposed major surfaces thereof are beveled. A pattern of metallization is provided on the opposed major surfaces of the blade substrate with the metallization extending over the tapered portions. The substrate is then back-ground to form a blunt edge extending between the tapered surfaces at the edge of the substrate. The metallization pattern further includes traces extending from the conductors along the blunt working edge of the blade to the handle receiving portion thereof and provide a means whereby RF energy may be conducted to the metallized working edge of the blade.

Abstract: An electrosurgical angioplasty catheter with ultrasonic enhancement is described. It comprises an elongated, flexible plastic tubular body having located at its distal tip an electrode structure for effecting rf cutting along with a transducer for ultrasonically driving the rf cutting electrodes and the support thereof. The electronics module for driving the cutting electrodes and the ultrasonic transducer also includes means for receiving echo signals picked up by the transducer whereby Doppler flow readings and ultrasound imaging of the blood vessel being worked upon can be obtained.

Abstract: An electro-surgical implement with an improved handle having a cutting mode of operation and a coagulating mode of operation. The implement includes a blade member having an electrically conductive pad area, and a predetermined pattern of electrical conductors. Electrical switch apparatus is contained in the handle member for altering the mode of operation between the cutting mode and coagulating mode when the handle member is in a locked disposition. Apparatus is also contained within the handle member for vibrating the blade member at a predetermined frequency and amplitude sufficient to create cavitation to prevent buildup of tissue and debris, and apparatus for energizing the blade for cutting and coagulating including apparatus for forcing the electrically conductive pad area against the vibration apparatus when the handle member is in a locked disposition. Mechanical switch apparatus is included to allow safe removal of the blade.

Abstract: An electrosurgical generator for driving one or more separate electrosurgical implements, e.g., an electrosurgical scalpel and an electrosurgical forceps, over separate output channels. Bipolar electrodes on the scalpel blade are energized by a radio frequency (rf) power source which, by proper manipulation of push-button switches on the scalpel handle, can be made to operate selectively in a CUT and in a COAG (coagulate) mode. In the CUT mode, the rf energy is applied to the tissue, via electrodes which are closely spaced, yielding a high current density. In the COAG mode, the energy is applied to electrodes which are spaced relatively far apart so as to produce heating sufficient to cauterize, but not to the point where the tissue is rent. The generator also provides circuitry for energizing an ultrasonic transducer mechanically coupled to one of the surgical implements whereby vibratory energy is simultaneously applied to the implement along with the rf CUT/COAG energy.

Abstract: A surgical cutting blade for use in an electrosurgical scalpel includes a thin flat ceramic substrate having a rounded tip where the edge portion of the substrate on the opposed major surfaces thereof are beveled. A pattern of metallization is provided on the opposed major surfaces of the blade substrate with the metallization extending over the tapered portions. The substrate is then back-ground to form a blunt edge extending between the tapered surfaces at the edge of the substrate. The metallization pattern further includes traces extending from the conductors along the blunt working edge of the blade to the handle receiving portion thereof and provide a means whereby RF energy may be conducted to the metallized working edge of the blade.

Abstract: An electrosurgical blade having a silicon nitride ceramic substrate having a beveled working edge with first and second conductive metal traces adhered to opposed side surfaces of the substrate along the working edge so as to be closely spaced relative to one another across the thickness dimension of the beveled working edge. Further conductive traces are formed on opposed sides of the substrate along the other edge of the substrate. In use, when a high RF voltage is applied between the traces extending along the working edge and the surgical blade is brought into contact with tissue, the relatively high current density causes relatively high heating to take place, bursting the cells and creating an incision. When a high RF voltage is applied between the traces separated by the width dimension of the substrate, the current density therebetween is significantly lower but sufficient to create enough heat to dehydrate tissue and blood cells whereby coagulation is achieved.

Abstract: Described is a surgical tool having a unique blade comprised of a blank made of electrically conductive material, a first insulative member, a plurality of electrically conductive members laminated to the first and insulative member and a second insulative coating. The blade acts as a capacitive device or as a resistive device depending upon the precise configuration of the second insulative coating.

Abstract: An electro surgical instrument comprising a handle and a replaceable blade. The handle includes a blade receiving slot and means for clamping the proximal portion of the blade within the slot. Also formed internally of the handle and within the slot is a cavity for containing an electrical-to-mechanical transducer and a plurality of conductive terminal pad areas. The blade is provided with a pattern of conductors which are insulated from one another and which lead to contact pad areas on the distal portion of the blade. When the blade is appropriately inserted into the handle and clamped in place, the transducer abuts the blade and electrical contact is established to energize the conductors and the transducer whereby the blade may be vibrated at a frequency and amplitude to limit the build-up of tissue debris on the blade during an electro surgery procedure.

Abstract: Apparatus for monitoring respiration and heartbeat and for processing electrical signals representative thereof, including circuits for developing a phase-shifted and amplitude-offset respiration signal for comparison with an original respiration signal for compensating for signal drift, and circuits for logically combining signals representative of the presence of respiration and heartbeat for eliminating certain false indications which may occur when only heartbeat exists.

Abstract: A proportioning system for preparing hemodialysis or hemofiltration solutions. The apparatus of the system is a specially plumbed tank containing a flexible plastic container which holds solution concentrate. Introduction of pressurized water into the tank outside the bag discharges concentrate and water through separate paths into a mixing chamber at a rate determined by the size ratio of narrow orifices in the respective paths.