Abstract: A sensor assembly for monitoring the respiration pattern of a subject is disclosed, the sensor comprising a sensor element for exposing to a gas stream exhaled by the subject comprising a first electrode, a second electrode and an active layer extending between the first and second electrodes to provide an electrical path therebetween, the sensor element being responsive to the concentration of water vapour in the gas stream exhaled by the subject, whereby the conductivity of the path between the electrodes varies in response to changes in the concentration of water vapour; a processor for determining the pattern of respiration of the subject; and means for displaying information relating to the determined respiration pattern to a user. The sensor assembly is particular suitable for measuring the respiration rate and/or depth of respiration of the subject. The sensor and method find particular application in the diagnosis and treatment of sleep apnea.

Abstract: An electrochemical sensor (40) is provided, the sensor comprising a working electrode (44); a counter electrode (46); and an ionic liquid medium extending between the working electrode and the counter electrode, the ionic liquid medium comprising an ionic liquid retained in a support material. The ionic liquid may comprise a cation selected from 1-alkyl-3-methylimidazolium ([CnMIM]), N-alkylpyridinium, tetraalkylammonium or tetraalkylphosphonium cations and an anion selected from hexafluorophosphate [PF6]; tetrafluoroborate [BF4]; trifluoromethylsulfonate [CF3SO3]; bis[(trifluoromethyl)sulfonyl]amide [(CF3SO2)2N]; trifluoroethanoate [CF3CO2]; acetate [CH3CO2]; nitrate, and halides, including fluoride [F] 1 chloride [Cl], and bromide [Br]. The sensor is particularly useful in the detection of gaseous components in the exhaled breath of a subject and for use in monitoring the lung function of the subject, for example to identify the onset of asthma and/or COPD.

Abstract: A method for the determination of the carbon dioxide content of an exhaled gas stream is provided, the method comprising measuring the water vapour content of the exhaled gas stream, and determining the concentration of carbon dioxide in the exhaled gas stream from the measured water vapour content. A particular method comprises causing the gas stream to impinge on a sensing element comprising a working electrode and a counter electrode; applying an electric potential across the working electrode and counter electrode; measuring the current flowing between the working electrode and counter electrode as a result of the applied potential; and determining from the measured current flow an indication of the concentration of the water vapour in the gas stream. A sensor is also described.

Abstract: An apparatus for monitoring the respiration of a subject, the apparatus comprises means for detecting the concentration of each of oxygen, carbon dioxide and nitric oxide in an inspired and/or exhaled gaseous stream of a subject; and a display for displaying the concentration of each of oxygen, carbon dioxide and nitric oxide. A method for monitoring the respiration of a subject comprises analysing the composition of the inspired and/or exhaled gas of the subject and determining the concentration of carbon dioxide, oxygen and nitric oxide in the gas; and displaying the results of the analysis on a display to provide an indication of the respiratory state of the subject. A method of determining the extent of resuscitation of a patient comprises measuring the concentration of carbon dioxide, oxygen and nitric oxide in the inspired gas stream and/or exhaled gas stream of the subject.