Effect of a Sciatic Block (SNB) Combined With a Continuous Femoral Block (CFNB) on Pain Scores After Knee Arthroplasty
- Conditions
- Postoperative Pain
- Interventions
- Procedure: CFNBProcedure: SNB plus CFNB
- Registration Number
- NCT01337115
- Lead Sponsor
- Centro Hospitalar do Porto
- Brief Summary
The purpose of this study is to determine if the addition of a sciatic nerve block (SNB) to a continuous femoral nerve block (CFNB) improves post-operative analgesia after knee arthroplasty.
- Detailed Description
Background: Postoperative pain after total knee replacement /arthroplasty (TKA) is a major concern. It is severe pain in 60% of patients and moderate in 30%. Continuous femoral nerve blocks (CFNB) are considered an excellent choice for regional anesthesia for major knee repair but there are some controversies about the need of supplemental obturator or sciatic nerve blocks for achieving better postoperative analgesia. A recent meta-analysis states there is no sufficient evidence to recommend or discharge these associations.
Objectives: We aim to assess the efficacy of the association of a sciatic nerve block (SNB) and a continuous femoral nerve block (CFNB) for reducing postoperative pain in patients submitted to TKA. Methods: A randomized controlled study on 50 patients submitted to TKA. Control group receives a femoral nerve block with a catheter before general anesthesia is induced and the intervention group gets a similar block plus a single shot SNB before general anesthesia. Both groups start a continuous local anesthetic infusion through femoral catheter after the end of surgery and supplemental oral diclofenac and paracetamol. Pain scores are measured until 24h postoperatively, side effects and patient satisfaction are monitored.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 50
- Unilateral total knee replacement
- Contra-indication for general anesthesia
- Infection on puncture site
- Coagulation disorders
- Pre-existent neuropathies
- Allergies to local anesthetics, paracetamol, diclofenac and tramadol
- Severe dyspepsia
- Less than 50kg weigh
- Body Mass Index (BMI) greater than 40
- American Society of Anesthesiologists (ASA) Physical Status 4 or 5
- Absence of capacity to use the Visual Analog Score (VAS) scale
- Refusal to give informed consent
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Continuous femoral nerve block (CFNB) CFNB A continuous femoral nerve block is performed for peri-operative analgesia and a bolus of 30 ml of ropivacaine 0.375% is injected before induction of general anesthesia and surgery starts. An infusion of 8ml/h of ropivacaine 0.2% is started in post anesthesia care unit (PACU) and maintained for 48h Single shot SNB plus CFNB SNB plus CFNB A single shot sciatic nerve block (SNB) is performed before surgery with 25ml of 0.2% ropivacaine in addition to the continuous femoral nerve block (CFNB) performed in the control group before induction of general anesthesia and surgery starts. An infusion of 8ml/h of ropivacaine 0.2% is started in Post anesthesia care unit (PACU) and maintained for 48h
- Primary Outcome Measures
Name Time Method Visual Analogue Scores (VAS) - Pain Scores Measured in mm (0-100) 15-30 min after arrival on post anesthesia care unit (PACU) Pain scores measured by Visual Analogue Score (VAS) scale at 15-30min after Post anesthesia care unit (PACU) arrival VAS is a 100mm scale to measure pain. 0mm - no pain 100mm - worst possible pain
VAS Results - Pain Measured in mm (0-100) 12h after surgery VAS pain scores are measured by blinded investigators 12h after surgery .
VAS scale:
0 - no pain 100 - worst possible painVAS Results - Pain Scores Measured in mm (0-100) 24h after surgery VAS pain scores are measured by blinded investigators 24h after surgery .
VAS scale:
0 - no pain 100 - worst possible pain
- Secondary Outcome Measures
Name Time Method Satisfaction With Anesthesia Technique in Each Arm of the Study 1 month after surgery Satisfaction with the anesthesia technique using a categorical scale with three levels:
Bad Reasonable Good/Very Good A Fisher's Exact test is made to asses any differences in the distribution of patients in each arm to each level of the categorical scale
Trial Locations
- Locations (1)
Centro Hospitalar do Porto, Serviço de Anestesia
🇵🇹Porto, Portugal