PRESSURE-VOLUME RELATIONS OF WOUND SUCTIO N DRAINAGE CONTAINERS AND SUCTION CAPACITY OF DRAINS

Four low-vacuum systems and eight high-vacuum systems were examined wi th special reference to the pressure-volume relations. The maximum fil ling volume for adequate transport of wound secretion was determined f or each type. The use of a synthetic wound fluid instead of water resu lted in a smaller aspiration volume. Enlargement of the tube diameter resulted in a reduced initial vacuum for the low-vacuum systems, where as the high-vacuum systems were not affected. Normal drain tubes were compared with ''Ulm drains'' and silicon tubes for suction capacity. T he suction maximum of normal tubes and silicon tubes was located at th e proximal holes of the perforated tubes. The ''Ulm drain,'' with perf oration diameter increasing continuously to the distal end of the tube , was found to exert suction even at the more distal part of the tube. It is estimated that this tube allows locally more balanced vacuum in the wound.