The present invention relates to the negative pressure devices for the lower part for treating the body of a patient, it include: a pressure chamber, including be configured to introduce patient body lower part to pressure chamber inside first be open, -- in the closure element of the periphery setting of the first opening, wherein closure element is configured to supply the body that an airtight sealing surrounds a patient, -- bed and second element including first element with the first couch surface, it has the second couch surface in the case where a gap between them allows closure element between first element and second element by movement. Bed is at least partly moveable between a treatment position, wherein outside of first element in pressure chamber, and second element is in pressure chamber, and one in on-position, wherein first element is further spaced from pressure chamber, and second element is at least partially disengaged from the inside of pressure chamber by the first opening, bed includes a frame element, wherein frame element is fixedly attached to first element and second element, and frame element extends through the inside that the second opening enters pressure chamber from the outside.
