Abstract: An arrangement for introducing a liquid into the body of a patient or for withdrawing a liquid from the body of a patient, including a first structural part carrying a cannula for positioning in the body of the patient, and a second structural part with a connection port for detachably coupling a conduit for supplying or withdrawing a liquid, wherein the first and second structural parts are connected, can be rotated relative to each another and in relative rotational positions form a channel for introducing a liquid from the conduit to the cannula or for withdrawing a liquid from the cannula to the conduit, and whereby movement of the conduit for coupling and uncoupling is transverse to the longitudinal axis of the cannula.

Abstract: According to one embodiment, a cannula assembly may include a cannula module and an inserter module. In the pre-operational state the cannula is retracted with respect to the skin-contacting surface. In operational state the cannula projects beyond the skin-contacting surface. The inserter module may include an energy store and an activation mechanism. When the energy store is at least partially discharged, the stored potential energy is transformed to kinetic energy that moves the cannula from the pre-operational state to the operational state. The activation mechanism is triggerable from outside the cannula assembly with a trigger device. The activation mechanism prevents the energy store from being discharged before it is triggered by the trigger device, and enables the energy store to be discharge after it is triggered by the trigger device to force the cannula from the pre-operational state into the operational state.