A catheter arrangement including a catheter having a proximal end and a distal end and at least one continuous fluid channel, at the proximal end of which a fluid connection and at the distal end of which a nozzle is arranged, which has a cross section that can be varied by a force applied to the distal catheter end a liquid feed unit, connected to the proximal fluid connection of the catheter feeds liquid into the at least one fluid channel at a predetermined operating pressure. A flow sensor measures, during operation of the catheter arrangement, a pressure drop at the fluid channel. A pressure evaluation unit, connected on the input side in a signal-based manner to the flow sensor, determines a force applied to the distal end of the catheter from the measured pressure drop at the fluid channel and from predetermined deformation characteristics of the associated nozzle.
