Compression therapy of limb edema using hydrostatic pressure of mercury

A new apparatus for the treatment of edema of the extremities is described. The extremity is placed in a cylindrical vertical tank and isolated by a circumferential synthetic rubber membrane. The equipment is programmed to create a mold of the extremity using a slurry of plastic granules from a reservoir. Mercury is then pumped between the mold and the extremity, thereby exerting a pressure gradient on the extremity equal to the hydrostatic pressure of the mercury column. A computerized program forms the mold and runs several compression cycles for each treatment session. Twelve patients were treated (8 upper extremities, 4 lower extremities) on a weekly or semiweekly basis. Progress was followed with computed axial tomography scans, as well as measurements and photographs. Ten patients experienced significant immediate decrease in edema with each treatment. Wrapping or elastic support was required to prevent the return of edema between treatments. No pain, skin injury, or other complication of treatment was noted. The apparatus can safely provide short-term, immediate, significant improvement of extremity edema. Further studies will be necessary to determine long-term benefit.