An apparatus for delivery of fluids to a patient includes an inlet tube and an outlet tube connected to each other at an angular joint. A rotary valve and a piston are fitted to the angular joint forming a chamber. The rotary valve is provided with a priming channel notch and a pumping notch. For priming operation with the fluid delivery apparatus, a user sets the rotary valve to a priming position. During pumping operation, the rotary valve rotates in coordination with the piston to transfer a quantum of fluid from the inlet tube to the outlet tube via the chamber. A second piston is optionally provided on the outlet tube for smoothing out flow rate pulsations.