A kind of flowing group, the flowing group include check valve and two kinds of fluids successively can be applied to patient from a pair of of container. Predetermined rupture (threshold value) pressure of the check valve is that the inlet pressure of the first flowing instruction occurs, and can be set as predetermined value individually to minimize and/or prevent described two fluids free flows dynamic. A part of the flow path of the flow path and the second fluid that pipeline section is the first fluid is connected, and pumps and may be connected to the connection pipeline section. By inverting the pumping direction of the pump, described two fluids can in turn be pumped out from the pair of container, and be therefore successively applied to patient.
