Flow switching device for catheterization with a three way catheter comprising: - a housing (7) having four opening (11, 12, 13, 14)； - a first, second and third distal hydraulic conduit (1, 2, 3), originating at the first, second and third opening (11, 12, 13), respectively； - switching means 20 engaging with the housing from obtaining a first operative configuration, wherein the first and third opening (11,13) are in communication； a second operative configuration, wherein the second and fourth opening (12, 14) are in communication； a third operative configuration, wherein the first and second opening (11, 12) are in communication； a fourth operative configuration wherein the second and third opening (12,13) are in communication； and - hydraulic bifurcation (17) comprising: a respective proximal hydraulic branch (6) originating from said fourth opening (14), a fourth and fifth distal hydraulic conduit (4, 5) originating distally from said proximal hydraulic branch and which are fluid dynamically communicating with respect to each other.
