BaCPAKS trial In 'BaCPAKS' BaCPAKS trial - How the study worksBaCPAKS trial - Contact UsBaCPAKS Trial Overview BaCPAKS nerve Block for Chronic Pain After Knee replacement Surgery The BaCPAKS Trial was designed in response to an NIHR's Health Technology Assessment (HTA) commissioned call (23/107) to investigate the clinical and cost-effectiveness of nerve blocks for reducing pain after knee replacement surgery. Research question What is the clinical and cost-effectiveness of adding an adductor canal nerve block (ACB) to local infiltration analgesia (LIA) for primary elective knee replacement (KR) surgery? Background Primary knee replacement (KR) is one of the most painful surgical operations, with up to 60% of patients complaining of moderate-to-severe pain during the hospital stay. Unmanaged acute postoperative pain may lead to chronic postsurgical pain (CPSP), a highly debilitating condition affecting up to 44% of patients after KR. Perioperative nerve blocks may reduce the risk of transition from acute to chronic pain. Aim To conduct a multicentre randomised controlled trial, with an internal pilot and economic evaluation, to compare the clinical and cost-effectiveness of ACB plus LIA versus LIA only, in primary elective KR surgical patients. Primary Objectives To determine if there is a difference in the magnitude of chronic pain at 6-months after KR surgery, between the ACB and usual care with LIA To complete a 6-month internal pilot to estimate the feasibility of recruitment To estimate the difference between the intervention and control groups with respect to a range of patient-reported and clinical secondary outcomes To explore the differential effect of nerve block within pre-specified sub-groups To assess the relative cost effectiveness To conduct a ‘Study Within A Trial’ (SWAT) to investigate methods for increasing participants’ understanding of the trial results, by comparing written with animated formats of dissemination Design Multicentre, randomised, double-blind (participants and assessors), sham-controlled trial, with an embedded pilot, a SWAT and an economic evaluation Population Any adult undergoing primary KR surgery for any indication Intervention ACB plus LIA, in addition to general and/or spinal anaesthesia Comparator Sham-ACB plus LIA, in addition to general and/or spinal anaesthesia Primary outcome Pain magnitude at 6 months post-surgery, measured by the “worst pain” item of the Brief Pain Inventory (BPI) Secondary outcomes Patient reported outcomes (acute and chronic pain; quality of life; pain interference, neuropathic pain) Health outcomes (opioid consumption, time to mobilise, complications, secondary procedures) Resource utilisation Follow-up ‘Acute’ phase: days 0-3 post-surgery ‘Chronic’ phase: 3-, 6- and 12-months post-surgery Timelines for delivery Months 1-9 (9 months): Trial preparation and start-up Months 10-15 (6 months): Internal pilot Months 16-33 (18 months): Main trial recruitment Months 34-45 (12 months): Follow-up Month 46-51 (6 months): Analyses and publication of results Month 49-57 (9 months): SWAT Duration 57 months (from 1st April 2025 until 31st December 2029) Chief Investigator Dr Ciro Morgese Consultant Anaesthetist at University Hospitals Birmingham (Queen Elizabeth Hospital) and Honorary Associate Professor at University of Birmingham Sponsor University of Birmingham Contact bacpaks@trials.bham.ac.uk