Abstract: Volumetric pump for use in the parenteral perfusion of solutions without the need for the substitution or inclusion of additional elements in traditionally used dropper systems. The pump consists of a rigid chamber (1) containing a bag (2) with the solution to be perfused and is set up in a common volume formed by a liquid or gaseous interface with another chamber (3) to which it is connected, acting as a pump or pumping agent, and equipped with a distendable membrane (4), which acts on the walls of the bag (2), extracting the residual air by means of suction through the duct (8) which has a valve (5). The solution then passes through a connection tube (6) and is perfused. There is a stopcock (7) in the passage connecting the compartments (1) and (3), and the system is equipped with timers (9) which enable the selected flow to be determined and a servomechanism (10) to ensure greater precision.