The application relates to a drainage device (20) comprising an aspiration pouch (22) supported by a sheet-like element (25) which is constituted by a hydrocolloid substance, the sheet-like element (25) being arranged on a bottom side of the aspiration pouch (22) and overlapping at least partially the aspiration pouch (22), the aspiration pouch (22) comprises a least one draining layer (26) encapsulated by a gas- and fluid tight foil (27) such that the aspiration pouch (22) and the draining layer (26) form an integral part, and the aspiration pouch (22) is connectable to aspiration means by way of a connecting element (24) which is provided on the top of the draining layer (26) such that, in use, the draining layer (26) is arranged between a cavitary lesion and the connecting element (24),and the draining layer (26) is formed of a porous material.
