A medical apparatus for local application of a fluid, comprising a flexibly deformable outer tube (1, 21, 41, 61) having a tube wall, the outer tube (1, 21, 41, 61) having a plurality of continuous openings (2, 22, 42, 62) in the tube wall, at least one of the plurality of continuous openings (2, 22, 42, 62) being arranged in the region of a first end (3, 23, 43, 63) of the outer tube (1, 21, 41, 61), a flexible inner tube, the inner tube being arranged at least in regions inside the outer tube (1, 21, 41, 61), the inner tube, in an expanded state, having an outer diameter which is at least as large as the inner diameter of the outer tube (1, 21, 41, 61), such that the inner tube closes the continuous openings (2, 22, 42, 62) in the outer tube (1, 21, 41, 61) in the expanded state on the inside of the outer tube (1, 21, 41, 61), the outer diameter of the inner tube being transferable from the expanded state to a radially contracted state with a smaller outer diameter of the inner tube, such that the openings (2, 22, 42, 62) are exposed, a connection (5, 25, 45, 65) rigidly interconnecting and fluid-tightly closing the outer tube (1, 21, 41, 61) and the inner tube at the first end (3, 23, 43, 63) of the outer tube (1, 21, 41, 61), and a connector (6, 26, 46, 66) for feeding the fluid into the space between the inside of the outer tube (1, 21, 41, 61) and the outside of the inner tube, the connector (6, 26, 46, 66) being arranged in the region of a second end of the outer tube (1, 21, 41, 61), the second end of the outer tube (1, 21, 41, 61) being arranged opposite the first end (3, 23, 43, 63) of the outer tube (1, 21, 41, 61), characterized in that the expanded state is the relaxed state of the inner tube and can be transferred to the radially contracted state by means of application of force. a flexibly deformable outer tube (1, 21, 41, 61) having a tube wall, the outer tube (1, 21, 41, 61) having a plurality of continuous openings (2, 22, 42, 62) in the tube wall, at least one of the plurality of continuous openings (2, 22, 42, 62) being arranged in the region of a first end (3, 23, 43, 63) of the outer tube (1, 21, 41, 61), a flexible inner tube, the inner tube being arranged at least in regions inside the outer tube (1, 21, 41, 61), the inner tube, in an expanded state, having an outer diameter which is at least as large as the inner diameter of the outer tube (1, 21, 41, 61), such that the inner tube closes the continuous openings (2, 22, 42, 62) in the outer tube (1, 21, 41, 61) in the expanded state on the inside of the outer tube (1, 21, 41, 61), the outer diameter of the inner tube being transferable from the expanded state to a radially contracted state with a smaller outer diameter of the inner tube, such that the openings (2, 22, 42, 62) are exposed, a connection (5, 25, 45, 65) rigidly interconnecting and fluid-tightly closing the outer tube (1, 21, 41, 61) and the inner tube at the first end (3, 23, 43, 63) of the outer tube (1, 21, 41, 61), and a connector (6, 26, 46, 66) for feeding the fluid into the space between the inside of the outer tube (1, 21, 41, 61) and the outside of the inner tube, the connector (6, 26, 46, 66) being arranged in the region of a second end of the outer tube (1, 21, 41, 61), the second end of the outer tube (1, 21, 41, 61) being arranged opposite the first end (3, 23, 43, 63) of the outer tube (1, 21, 41, 61), characterized in that the expanded state is the relaxed state of the inner tube and can be transferred to the radially contracted state by means of application of force.