Dexmedetomidine as an Adjunct to Periarticular Ropivacaine in Total Knee Replacement: A Pilot Randomised Controlled Trial
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Ropivacaine + saline solution, Ropivacaine + Dexmedetomidine.
- Who it may be relevant to
- Registry conditions: Postoperative Pain Management in Total Knee Arthroplasty. Basic parameters: 18 years — 100 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Malaysia
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
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
Overview
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.
Detailed description
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.
Interventions
- Drug Ropivacaine + saline solution
0.5% ropivacaine (19 mL) + 1 mL normal saline administered intraoperatively via periarticular injection. - Drug Ropivacaine + Dexmedetomidine
0.5% ropivacaine (19 mL) + dexmedetomidine 100 µg in 1 mL administered intraoperatively via periarticular injection.
Primary outcome measures
- 24-hour postoperative pain score (NRS 0-10) at rest and during movement [Time frame: 24 hours postoperatively (from time of skin closure)]
Secondary outcome measures (4)
- Total postoperative opioid consumption (MME) [Time frame: 24 hours postoperatively]
- Patient satisfaction with pain management [Time frame: Postoperative day 1]
- Incidence of adverse effects (sedation, bradycardia, hypotension, PONV) [Time frame: Within 24 hours postoperatively]
- Time to first ambulation [Time frame: From end of surgery to first ambulation (within 24 hours)]
Eligibility criteria
Inclusion criteria
- 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
Exclusion criteria
- Known allergy to study drugs
- Chronic pain or neurological conditions
- Bilateral or revision TKR
- Significant deformity affecting function
- Substance abuse history
- Day-case surgery
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Allocation
- Randomized
- Model
- Single group
- Masking
- Triple blind
- Primary purpose
- Treatment
Study locations
Malaysia · 1 center
- Universiti Malaya Medical Centre — Kuala Lumpur
Identifiers
NCT: NCT07176065 · 2025429-15014