Clinical trial NCT01337115: Effect of a Sciatic Block (SNB) Combined With a Continuous Femoral Block (CFNB) on Pain Scores After Knee Arthroplasty
Official title: Effect of a Single Shot Sciatic Nerve Block (SNB) Combined With a Continuous Femoral Block (CFNB) on Pain Scores After Knee Arthroplasty. A Randomized Controlled Trial
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Postoperative Pain
Keywords: Postoperative pain
Knee arthroplasty
Peripheral nerve blocks
Sciatic nerve block
Femoral nerve block
Lead sponsor: Centro Hospitalar do Porto
Sponsor class: OTHER
Collaborators: name: Universidade do Porto
First posted: 2011-04-18
Enrollment: 50
Sex: ALL
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

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.

Eligibility criteria: Inclusion Criteria:

* Unilateral total knee replacement

Exclusion Criteria:

* 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

Primary outcomes:
measure: Visual Analogue Scores (VAS) - Pain Scores Measured in mm (0-100)
timeFrame: 15-30 min after arrival on post anesthesia care unit (PACU)
measure: VAS Results - Pain Measured in mm (0-100)
timeFrame: 12h after surgery
measure: VAS Results - Pain Scores Measured in mm (0-100)
timeFrame: 24h after surgery
Secondary outcomes:
measure: Satisfaction With Anesthesia Technique in Each Arm of the Study
timeFrame: 1 month after surgery
Other outcomes:
Locations:
city: Porto
country: Portugal
facility: Centro Hospitalar do Porto, Serviço de Anestesia
Study officials:
affiliation: Centro Hospitalar do Porto
name: Raul MS Carvalho, MD
role: PRINCIPAL_INVESTIGATOR
References: