Lower-extremity amputation is a critical surgical procedure performed when the tissues of the leg and foot become nonviable or dysfunctional due to various reasons, such as ischemia, infection, trauma, or malignancy. Despite advancements in pain management, postoperative pain after major lower limb amputation remains a significant challenge for both clinicians and patients. The postoperative pain plays a crucial role in determining overall patient satisfaction with their surgical experience.

The use of opioids for pain relief is common, but they come with side effects and potential complications, such as, respiratory depression, pruritus, nausea, vomiting, hemodynamic changesbradycardia, hypotension, to name a few, leading to increased hospital costs and prolonged stay. To improve postoperative pain management, the American Society of Anaesthesiologists(ASA) recommends the use of peripheral wound catheters (PWCs) with local anesthetics. Perineural catheters (PNCs) are a type of PWC specifically placed near major nerves to allow continuous infusion of local anesthetics directly into the perineural space. The study aims to investigate the analgesic advantage of surgically placed PNCs for Below-Knee Amputation (BKA), providing valuable insights into the efficacy and feasibility of this postoperative analgesic technique.

All patients fulfilling the eligible criteria will be recruited into the study after obtaining informed consent on the day before the surgery. PNC will be placed surgically intraoperatively. As per the current protocol, they will be administered intermittent boluses of local anaesthetics (via the catheter), either with an automated bolus pump or manually injections. The postoperative pain assessment will be carried out using the Numerical Rating Scale (NRS) score by the pain team.