Abstract: The hematocrit of blood (i.e., the percentage of whole blood volume occupied by red blood cells) perfusing a finger is determined by stimulating the finger with two current frequencies, one relatively high (e.g., 10 MHZ) and the other relatively low (e.g., 100 KHz). Voltages induced in the finger in response to the two current frequencies are then captured and separated into baseline and pulsatile components. The hematocrit is determined as a function of the ratio of the high frequency pulsatile component to the low frequency pulsatile component, multiplied by the ratio of the square of the low frequency baseline component to the square of the high frequency baseline component. The volume of blood perfusing the body part at which hematocrit is to be measured may be increased on each pulse by the application of external pressure to the finger, such as by applying a pressure cuff to the finger. Assemblages including two pairs of electrodes are used to effect the determination of hematocrit.

Abstract: An apparatus for sampling blood through an intravenous or intraarterial tube which does not interfere with normal operation of an infusion operation or a direct pressure monitoring operation. A needleless sampling site at which fluid can be removed is connected to the tube. A chamber is provided which is connected to the tube such that fluid can be interchanged between the tube and the chamber. A plunger is provided for drawing the fluid from the tube into the chamber and for expelling the fluid from the chamber into the tube. In its normal position, the plunger blocks the interconnection between the tube and the chamber. When in its sampling position, the plunger creates a vacuum in the chamber causing the fluid in the tube to be aspirated into the chamber. The aspirating action causes fluid in the patient to be drawn up to the sampling site. An actuator, which can be operated by a single hand of a medical practitioner, imparts an appropriate feel to the system operation.

Abstract: The hematocrit of blood (i.e., the percentage of whole blood volume occupied by red blood cells) perfusing a finger is determined by stimulating the finger with two current frequencies, one relatively high (e.g., 10 MHZ) and the other relatively low (e.g., 100 KHz). Voltages induced in the finger in response to the two current frequencies are then captured and separated into baseline and pulsatile components. The hematocrit is determined as a function of the ratio of the high frequency pulsatile component to the low frequency pulsatile component, multiplied by the ratio of the square of the low frequency baseline component to the square of the high frequency baseline component. The signal-to-noise ratio of the captured voltages can be enhanced by the application of external pressure to the finger, such as by applying a pressure cuff to the finger.

Abstract: The present invention provides an efficient and cost effective device for applying electrical stimulation to a body cavity. Preferred embodiments of the invention also provide the function of measuring the pressure exerted by the body cavity. The present invention is particularly useful when treating urinary incontinence in females. By providing electrical stimulation to the vagina, the present invention strengthens the pelvic floor muscles to improve urinary continence. The preferred embodiments of the invention which provide the function of measuring the pressure exerted by the body cavity convey to a user in a humanly perceptible manner the pressure exerted by the body cavity in order to provide feedback on the strengthening of the pelvic floor muscles. Most advantageously, a carrier structure which is inserted into the body cavity is fabricated from a low cost material, such as an injection molded thermoplastic material.

Abstract: A subcutaneous radiation reflection probe for measuring oxygen saturation in living tissue includes an elongate drive shaft on one end of which is detachably coupled a mounting cup. The mounting cup includes a hollow for receiving and holding a base element on which is mounted a spiral needle which coils outwardly from the mounting cup to terminate in a pointed end. A window is formed in the spiral needle near the pointed end thereof for receiving and holding a radiation emitter, such as a light emitting diode. A radiation detector is disposed on the base element within the coil of the spiral needle. The probe may be used to measure oxygen saturation in living tissue, such as a fetal scalp, by inserting the mounting cup and drive shaft through an introducer into a woman's vagina until the spiral needle contacts the fetal scalp.

Abstract: An apparatus for sampling blood through an intravenous or intraarterial tube which does not interfere with normal operation of an infusion operation or a direct pressure monitoring operation. A needleless sampling site at which fluid can be removed is connected to the tube. A chamber is provided which is connected to the tube such that fluid can be interchanged between the tube and the chamber. A plunger is provided for drawing the fluid from the tube into the chamber and for expelling the fluid from the chamber into the tube. In its normal position, the plunger blocks the interconnection between the tube and the chamber. When in its sampling position, the plunger creates a vacuum in the chamber causing the fluid in the tube to be aspirated into the chamber. The aspirating action causes fluid in the patient to be drawn up to the sampling site. An actuator, which can be operated by a single hand of a medical practitioner, imparts an appropriate feel to the system operation.

Abstract: A subcutaneous radiation reflection probe for measuring oxygen saturation in living tissue includes an elongate drive shaft on one end of which is detachably coupled a mounting cup. The mounting cup includes a hollow for receiving and holding a base element on which is mounted a spiral needle which coils outwardly from the mounting cup to terminate in a pointed end. A window is formed in the spiral needle near the pointed end thereof for receiving and holding a radiation emitter, such as a light emitting diode. A radiation detector is disposed on the base element within the coil of the spiral needle. The probe may be used to measure oxygen saturation in living tissue, such as a fetal scalp, by inserting the mounting cup and drive shaft through an introducer into a woman's vagina until the spiral needle contacts the fetal scalp.

Abstract: A subcutaneous radiation reflection probe for measuring oxygen saturation in living tissue includes an elongate drive shaft on one end of which is detachably coupled a mounting cup. The mounting cup includes a hollow for receiving and holding a base element on which is mounted a spiral needle which coils outwardly from the mounting cup to terminate in a pointed end. A window is formed in the spiral needle near the pointed end thereof for receiving and holding a radiation emitter, such as a light emitting diode. A radiation detector is disposed on the base element within the coil of the spiral needle. The probe may be used to measure oxygen saturation in living tissue, such as a fetal scalp, by inserting the mounting cup and drive shaft through an introducer into a woman's vagina until the spiral needle contacts the fetal scalp.

Abstract: A system and method for multiplexing two lumens of a catheter to a single pressure transducer and monitor setup such that the pressure found in either of the two lumens may be alternately monitored. Included in the present invention is a pressure multiplexing valve provided with a four-port body and a rotor which may be selectively rotated to either of two monitoring positions. The rotor is provided with passageways that interconnect the ports. In one embodiment both catheter lumens are always connected to a medical infusion device regardless of which lumen is connected to the transducer. In another embodiment, one lumen is shut off when not connected to the transducer. The present invention provides a compact system removably mounted on a single carrier.

Abstract: A system and method for muliplexing two lumens of a catheter to a single pressure transducer and monitor setup such that the pressure found in either of the two lumens may be alternately monitored. Included in the present invention is a pressure mulitplexing valve provided with a four-port body and a rotor which may be selectively rotated to either of two monitoring positions. The rotor is privided with passageways that interconnect the ports. In one embodiment both catheter lumens are always connected to a medical infusion device regardless of which lumen is connected to the transducer. In another embodiment, one lumen is shut off when not connected to the transducer. The present invention provides a compact system removably mounted on a single carrier.