A vascular clamp, has an operating mechanism, and an actuating tool. The vascular clamp is grasped using a detachable operating mechanism, wherein an actuating tool that can be slid in and out is able to open and close the jaws of the grasped vascular clamp. The vascular clamp includes a coupling arrangement and a continuously adjustable adjustment mechanism for this purpose. In order to grasp the vascular clamp, the operating mechanism includes a gripping mechanism and is equipped with a locking mechanism, which are used to create a detachable connection between the vascular clamp and the operating mechanism. For stepless opening and closing, the actuating tool engages in the adjustment mechanism of the vascular clamp and opens and closes the jaws of the vascular clamp by corresponding rotation of the actuating tool. The surgical instrument according to the invention is disassemblable and reassemblable, and can advantageously be disassembled into its three constituent parts during an operation, thus keeping the access opening in the chest free from obstructing instruments.