The Effect of Continuous Femoral Nerve Block With Modulation of Depth of Anesthesia on Prognosis of Patients Receiving Total Knee Arthroplasty

Min Su

Status: Unknown

Conditions: Peripheral Nerve Block; Pain Management; Sedation; Total Knee Arthroplasty

Treatments: Procedure: post-operative continuous femoral nerve block; Drug: ropivacaine; Procedure: peri-operative continuous femoral nerve block with light sedation; Device: insulated needle (Contiplex B Braun, Melsungen, Germany); Device: ultrasound; Drug: saline; Drug: lidocaine

Study type: Interventional

Funder types: Other

Identifiers

NCT02576015

CYYYMZK-07

Details and patient eligibility

About

The interaction of analgesia and sedation ot their effect on the prognosis of surgical patients still need to be elucidated.Currently, how to optimize intra-operative Analgesia and sedation to improve the prognosis of surgical patients is still a mystery.Intra-operative nerve block provided regional analgesia of the operated knee, which reduced the dosages of sedatives and analgesics.Based on a pilot study,the investigators found a decrease of post-operative adverse composite outcomes with the use of continuous femoral nerve block (2% versus 7%) ,therefore, the investigators postulate that general analgesia with lighter sedation in combination with peripheral nerve block could reduce the post-operative morbidity compared with deeper sedation.This randomized controlled trial is designed to test this hypothesis in patients receiving unilateral knee arthroplasty.

Full description

This study was approved by the institutional review board of the First Affiliated Hospital of Chongqing Medical University. The protocol design is in accordance with Consolidated Standards of Reporting Trials (CONSORT) statement.This study is designed as a randomized controlled trial to compare intra-operative continuous femoral nerve block combined with lighter anesthetic depth (group L) with deeper anesthetic depth (group D) monitored by bispectral index (BIS). All potentially eligible participants will be asked to give written informed consent before they are enrolled in this study.The following outcomes will be assessed:post-operative major complications (post-operative pulmonary infection,need of mechanical respiratory support,myocardio-infarction,deep venous thrombosis, pulmonary embolism, stroke, poor wound healing,all-cause post-operative death within 30 days).Secondary Outcomes included :acute post-operative pain assessed by visual analogue scale and dosages of rescue medications;Dosages of intra-operative vasopressors,anesthetics and analgesics;Life quality measured by EQ-5D questionnaire 3 months post-operatively;adverse events associated with the femoral catheter (displacement, infection, hematoma,drop-out of catheter).

Enrollment: 380 estimated patients

Sex: All

Ages: 18 to 80 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Men and women over the 18 years and younger than 80 years old
• Scheduled to receive selective unilateral knee replacement.

Exclusion criteria

• Bilateral knee replacement
• The secondary knee revision and knee surgery not interfering with articular joint cavity (wound debridement and suture)
• American Society of Anesthesiology (ASA) classification of anesthesia risk IV and V grade
• Body mass index higher than 35
• Coagulation dysfunction, which is assessed by activated partial thromboplastin time (APTT) higher than the upper limit by 10s; prothrombin time (PT) higher than the upper limit by 5s; International Normalized Ratio (INR) higher than 1.3, or any of criteria met above;
• Pre-operative hypoxia (SpO2< 90% or PO2<60 mmHg)
• Pre-operative hypercapnia (PCO2> 50 mmHg)
• Local infection of puncture sites
• Neurological diseases and pre-operative psychological disorders
• Uncontrolled general infection
• Intra-operative cardiac arrest.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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380 participants in 2 patient groups

Group L

Experimental group

Description:

Participants in group L will receive a single injection for femoral nerve block combined with continuous femoral nerve block intra-operatively. The femoral nerve block will be performed before the induction of anesthesia on the leg to be operated. Then the patients were given the 2% lidocaine 10 ml and 1% ropivacaine 10 ml as initial dose,then,the patients will receive a continuous infusion of 0.15% ropivacaine at 15 ml/h.Intra-operatively, bispectral index score (BIS) was titrated with the adjusting of desflurane to maintain the index between 50-60.After the surgery,these patients will receive continuous femoral nerve analgesia till 3 days post-operatively( the loading dose was set at 5 ml of 0.15% ropivacaine followed by an infusion of 0.15% ropivacaine at 5 ml/h, with bolus of 5 ml and the lock time of 30 min).

Treatment:

Procedure: peri-operative continuous femoral nerve block with light sedation

Device: insulated needle (Contiplex B Braun, Melsungen, Germany)

Drug: lidocaine

Device: ultrasound

Drug: ropivacaine

Group D

Sham Comparator group

Description:

Participants in group D will receive the placement of femoral nerve catheter preoperatively. The same dose of 0.9% saline was injected and infused as group L intra-operatively. Bispectral index score (BIS) was titrated with the adjusting of desflurane to maintain the index between 30-40.After the surgery,these patients will receive continuous femoral nerve analgesia till 3 days post-operatively( the loading dose was set at 5 ml of 0.15% ropivacaine followed by an infusion of 0.15% ropivacaine at 5 ml/h, with bolus of 5 ml and the lock time of 30 min).

Treatment:

Drug: saline

Device: ultrasound

Drug: ropivacaine

Procedure: post-operative continuous femoral nerve block