The invention relates to an assembly for treating wounds and to a hand held unit for treating wounds. The assembly and the hand held unit comprise a device for producing a plasma and/or an excited gas or gas mixture by means of a piezoelectric transformer, which is housed together with a circuit board in a housing of the device, and the assembly comprises an expansion element. A control circuit, to which the piezoelectric transformer is electrically connected, is realized on the circuit board. A second end of the expansion element surrounds a wound region to be treated. A first end of the expansion element is detachably connected to the housing of the device at the opening of the housing. The produced plasma and/or excited gas or gas mixture thus enters the expansion element from the opening of the housing.
