Effect of a Sciatic Block (SNB) Combined With a Continuous Femoral Block (CFNB) on Pain Scores After Knee Arthroplasty

NCT ID: NCT01337115

Last Updated: 2012-06-19

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 50 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2011-04-30
• Study Completion Date: 2012-03-31

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.

Conditions

Postoperative Pain

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: DOUBLE

Study Groups

Continuous femoral nerve block (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

Group Type: ACTIVE_COMPARATOR

CFNB

Intervention Type: PROCEDURE

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

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

Group Type: EXPERIMENTAL

SNB plus CFNB

Intervention Type: PROCEDURE

A single shot sciatic nerve block (SNB) is performed with 25 ml of 0.2% ropivacaine before surgery in addition to an isolated continuous femoral nerve block (CFNB) in the control group

Interventions

SNB plus CFNB

A single shot sciatic nerve block (SNB) is performed with 25 ml of 0.2% ropivacaine before surgery in addition to an isolated continuous femoral nerve block (CFNB) in the control group

Intervention Type: PROCEDURE

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

Intervention Type: PROCEDURE

Other Intervention Names

Peripheral nerve blocks; Local anesthetics; Ropivacaine; Femoral nerve block; Sciatic nerve block; Peripheral nerve blocks; Local anesthetics; Ropivacaine; Femoral nerve block

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

• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Universidade do Porto

OTHER

Sponsor Role: collaborator

Centro Hospitalar do Porto

OTHER

Sponsor Role: lead

Responsible Party

Raul Carvalho

Anesthesiology Consultant

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Raul MS Carvalho, MD

Role: PRINCIPAL_INVESTIGATOR

Centro Hospitalar do Porto

Locations

Centro Hospitalar do Porto, Serviço de Anestesia

Porto, Porto District, Portugal

Countries

Portugal

Other Identifiers

TA 007/11(004-DEFI/007-CES)

Identifier Type: -

Identifier Source: org_study_id