A bellows suction device is described for draining wounds that is similar to the Hemovac, but has certain advantages. These include valves to avoid contamination via back flow through the inlet and loss of suction via the outlet, and a calibrated reservoir to measure drainage.
Landes RR, Melnick I. An Improved Suction Device for Draining Wounds. Arch Surg. 1972;104(5):707. doi:10.1001/archsurg.1972.04180050081019