moisture sensing device for use with a device to monitor a patient's access. The invention relates to a moisture sensing device (40) for use with a device B for monitoring a patient's access to equipment with which, through a conductive tube, fluid is supplied to a patient and / or a fluid is withdrawn from the patient especially into a device for treating extracopore blood a. The device according to the invention for detecting moisture is formed as a flat structure to be placed on the patient's skin which, as a moisture sensor, has an electrically conductive structure. The device is noteworthy in that the flat structure is a flat textile structure, which is formed from both non-conductive warp and weft yarns as well as conductive warp and weft yarns as well as warp and weft yarns. conductors (50,60). the conductive and nonconductive warp and weft threads are arranged such that the electrically conductive structure is produced. Through spatial separation of the warp and weft threads, a defined electrically conductive structure is produced in the tissue. A decisive advantage of using both conductive warp and conductive weft yarns is that an electrically conductive structure can be formed which has sections extending in different directions. With such a structure, it can be produced in humidity sensor, which has a particularly high sensitivity. the electrically conductive structure is preferably closed with a terminating resistor r, which preferably is not a component of the device for detecting moisture, but rather a connecting piece for the device, so that production is simplified.dispositivo para detectar umidade para usar com um dispositivo para monitorar o acesso um paciente. a invenção se refere a um dispositivo (40) para detectar umidade para usar com um dispositivo b para monitorar o acesso a um paciente para um equipamento, com o qual, através de um tubo condutor, um fluido é fornecido a um paciente e/ou um fluido é retirado do paciente especialmente para um