A Pilot Randomized Controlled Trial Assessing the Impact of Dexmedetomidine as an Adjunct to Periarticular Ropivacaine Infiltration on Postoperative Pain and Recovery in Patients Undergoing Total Knee Replacement
试验速览
- 阶段
- 4 期
- 状态
- 尚未招募
- 入组人数
- 60
- 试验地点
- 1
- 主要终点
- 24-hour postoperative pain score (NRS 0-10) at rest and during movement
研究概览
简要总结
This study aims to evaluate whether adding dexmedetomidine to ropivacaine-based periarticular infiltration (PAI) improves postoperative pain control in patients undergoing total knee replacement (TKR). Despite standard pain management, many patients continue to experience moderate-to-severe pain after surgery. Dexmedetomidine, a sedative and analgesic agent, may help prolong the effect of local anaesthetics. A total of 60 patients will be randomly assigned to receive either ropivacaine alone or ropivacaine with dexmedetomidine. Pain scores, opioid use, side effects, and recovery time will be monitored for 24 hours. The goal is to determine if this method is more effective and safer for improving recovery after knee surgery.
详细描述
Total knee replacement is associated with significant postoperative pain despite the use of multimodal analgesia. Periarticular infiltration (PAI) using local anaesthetics such as ropivacaine has become a common component of pain control protocols but offers a limited duration of relief. Dexmedetomidine, a selective α2-adrenergic agonist, has demonstrated analgesic benefits as an adjuvant in peripheral nerve blocks, but its role in PAI remains underexplored.
This double-blind randomised controlled trial will recruit 60 adult patients undergoing unilateral total knee replacement at Universiti Malaya Medical Centre. Patients will be randomly assigned to receive either PAI with 0.5% ropivacaine alone (control group) or ropivacaine combined with 100 µg dexmedetomidine (intervention group). All patients will receive spinal anaesthesia and an adductor canal block before surgery.
Pain scores will be recorded using the Numerical Rating Scale (NRS) at 1, 6, 12, and 24 hours postoperatively. Secondary outcomes include 24-hour opioid consumption (morphine milligram equivalents), patient satisfaction (5-point Likert scale), adverse effects (sedation, bradycardia, hypotension, PONV), and time to first ambulation. This study will provide important feasibility data and inform the design of a future multicentre trial, particularly within the Malaysian population.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Single Group
- 主要目的
- Treatment
- 盲法
- Triple (Participant, Care Provider, Outcomes Assessor)
盲法说明
The study will be conducted in a quadruple-blinded manner. Group allocation will be concealed using computer-generated randomisation and sequentially numbered, opaque, sealed envelopes. A designated research team member, not involved in patient care or outcome assessment, will prepare the study drug (ropivacaine + saline or ropivacaine + dexmedetomidine) in identical, pre-labelled syringes. The operating surgeon, participant, and outcomes assessor will remain blinded to group allocation throughout the study period.
入排标准
- 年龄范围
- 18 Years 至 100 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Aged ≥18 years
- •Undergoing elective unilateral total knee replacement
- •ASA physical status I-III
- •No known allergy to local anaesthetics or dexmedetomidine
- •No opioid use >24 hours preoperatively
- •Provided informed consent
排除标准
- •Known allergy to study drugs
- •Chronic pain or neurological conditions
- •Bilateral or revision TKR
- •Significant deformity affecting function
- •Substance abuse history
- •Day-case surgery
研究组 & 干预措施
Ropivacaine + Saline
Patients will receive 20 mL of periarticular infiltration consisting of 19 mL of 0.5% ropivacaine and 1 mL of normal saline during total knee replacement.
干预措施: Ropivacaine + saline solution (Drug)
Ropivacaine + Dexmedetomidine
Patients will receive 20 mL of periarticular infiltration consisting of 19 mL of 0.5% ropivacaine and 100 µg dexmedetomidine in 1 mL during total knee replacement.
干预措施: Ropivacaine + Dexmedetomidine (Drug)
结局指标
主要结局
24-hour postoperative pain score (NRS 0-10) at rest and during movement
时间窗: 24 hours postoperatively (from time of skin closure)
Pain intensity will be assessed using the Numerical Rating Scale (NRS), where 0 indicates no pain and 10 indicates worst possible pain. Measurements will be taken at rest and during passive knee flexion to 90°, at 1, 6, 12, and 24 hours postoperatively. The primary endpoint is the NRS score at 24 hours.
次要结局
- Incidence of adverse effects (sedation, bradycardia, hypotension, PONV)(Within 24 hours postoperatively)
- Time to first ambulation(From end of surgery to first ambulation (within 24 hours))
- Total postoperative opioid consumption (MME)(24 hours postoperatively)
- Patient satisfaction with pain management(Postoperative day 1)
研究者
Ahmad Fariz Bin Elias
Clinical specialist
University of Malaya