A collection of sterile devices intended to be used in a clinical setting for continuous localized infusion of a single dose of analgesic medication (e.g., ropivacaine), using a non-electric/non-elastic mechanical infusion pump, for regional anaesthesia and postoperative pain management. It consists of a mechanical infusion pump prefilled with medication, and additional medication administration devices (e.g., infusion catheter). The infusion catheter is intended to be inserted during surgery and connected to the tubing line of the prefilled infusion pump for infusion of the drug into the operative site. The device can be worn by the patient during ambulation. This is a single-use device.