Abstract: The combined sensor with a thermostatted heating device (7, 23) for the simultaneous and continuous transcutaneous measurement of oxygen (O.sub.2) and of carbon dioxide (CO.sub.2) in the blood contains a measuring device (1) for the partial pressure of CO.sub.2 (pCO.sub.2), in which there is pure optical/spectrometric operation or which operates on the principle of pH measurement in a electrolyte (8), and which is separated from the measuring site on the skin by a membrane (13) which is permeable to both CO.sub.2 and light, and contains another measuring device (24, 25, 26) for the spectrometric measurement of the blood oxygen saturation (sO.sub.2). The advantage over a known pO.sub.2 /pCO.sub.2 combined sensor is that the combined sensor according to the invention can be operated at a low operating temperature of, for example, 42.degree. C.

Abstract: The combined sensor with a thermostatted heating device (7, 23) for the simultaneous and continuous transcutaneous measurement of oxygen (O.sub.2) and of carbon dioxide (CO.sub.2) in the blood contains a measuring device (1) for the partial pressure of CO.sub.2 (pCO.sub.2), in which there is pure optical/spectrometric operation or which operates on the principle of pH measurement in an electrolyte (8), and which is separated from the measuring site on the skin by a membrane (13) which is permeable to both CO.sub.2 and light, and contains another measuring device (24, 25, 26) for the spectrometric measurement of the blood oxygen saturation (sO.sub.2). The advantage over a known pO.sub.2 /pCO.sub.2 combined sensor is that the combined sensor according to the invention can be operated at a low operating temperature of, for example, 42.degree. C.

Abstract: Disclosed is an adapter assembly for accurately positioning a removable biosensor implanted in the cranium or skull cap. The assembly comprises an outer sleeve member insertable into a hole bored through the skull cap and an inner sleeve member coaxial with the outer sleeve. The sleeve members are constructed so as to permit slidable insertion and removal of the biosensor and to ensure accurate, tilt-free alignment thereof, thus enabling precise, error-free measurement.

Abstract: Disclosed herein is a retainer arrangement for applying a membrane to a physiological sensing unit for the transcutaneous determination of the magnitude of physiological quantitites, particularly for measuring the partial pressure of gases in blood or the like. The arrangement constitutes a preassembly of a membrane, with a clamping ring accommodating the membrane and having an annular recess receiving the rim of the membrane. The clamping ring has a lip in the form of an inwardly protruding annular edge for removably securing the clamping ring together with the membrane to the sensing unit by virtue of the lip resiliently snapping into a peripheral groove of the sensing unit, the lip defining the periphery of the annular recess. In accordance with the invention, an auxiliary retainer element, is provided for temporarily and removably assembling the membrane with the clamping ring prior to assembly with the sensing unit.

Abstract: Disclosed herein is a method for the calibration of a sensing unit for determining the partial pressure of oxygen in contact with the sensing unit. The method is of the type using a zero-calibration solution in which the partial pressure of oxygen is maintained at zero by virtue of a binding agent present in the solution for chemically combining with the oxygen. The essential steps of the method include adding to the solution a color indicator for indicating that the zero-calibration solution contains unspent binding agent, contacting the sensing unit with the zero-calibration solution containing the unspent binding agent and the color indicator, energizing the sensing unit, and adjusting the sensing unit until it indicates zero concentration.The invention also compasses within its scope a calibration agent for use in the performance of the method for supplying the zero-calibration solution upon dissolution in water, as well as a container for storing the zero-calibration solution.

Abstract: A sensor for transcutaneous measurement of physiological phenomena of living tissues is provided with a thermostatically-controlled electric heater. The purpose of the heater is to induce local hyperemia to enable operation of the sensor. The heater is thermostatically controlled. An independent temperature sensor is provided to disable the heater in the event of catastrophic failure of the thermostat circuit.

Abstract: A spring lancet holder for creating accurate standardized, reproducible puncture wounds in the skin for medical diagnostic purposes is disclosed in which accuracy and reproducibility is improved by minimizing the recoil transmitted to the lancet holder by actuation of the drive mechanism which pushes the lancet into the skin. In a preferred embodiment, a mass is shown which is caused to move in opposition to the motion of the lancet caused by a striker spring which is mounted between the lancet and the mass.

Abstract: A device is disclosed for applying a gas permeable membrane to an electrode. A collar is used to hold the membrane on the electrode. The device includes a guide bushing for forcing the collar over the membrane onto the electrode and includes a soft surface for maintaining a constant pressure against the membrane surface during the application.