Dexmedetomidine as Adjuvant for FNB in TKA

Sun Yat-sen University

Status: Completed

Conditions: Dexmedetomidine; Nerve Block

Treatments: Drug: Dexmedetomidine; Procedure: ultrasound-guided femoral nerve block; Procedure: Continuous femoral nerve block; Device: intravenous patient-controlled analgesia pump with morphine

Study type: Interventional

Funder types: Other

Identifiers

NCT03658421

[2018]45

Details and patient eligibility

About

The aim of the study was to find out whether addition of dexmedetomidine to lower concentration of ropivacaine preoperatively in femoral nerve block (FNB) would intensify analgesia and preserve quadriceps muscle strength after TKA.

Full description

We designed this study to evaluate whether dexmedetomidine added to lower concentration of ropivacaine for FNB can intensify analgesic effect and meanwhile reduce the possibility of lower limb (or quadriceps) weakness. Three groups were compared: 0.2% ropivacaine (H group), 0.1% ropivacaine (L group) and ropivacaine 0.1% added with 2 μg/kg dexmedetomidine (LD group).

Enrollment: 90 patients

Sex: All

Ages: 50 to 80 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• ASA I-II
• scheduled for total knee arthroplasty

Exclusion criteria

• refusal to participate in this study
• unicompartmental knee arthroplasty
• BMI > 35 kg/m2
• congnitive or phychiatric history
• refusal of general anesthesia
• contraindication to laryngeal mask airway insertion
• contraindication to peripheral nerve block (localized infections, sepsis, coagulopathy, bleeding diathesis or preexisting lower extremity neurological abnormality)
• allergy to the drugs used

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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90 participants in 3 patient groups

H group

Experimental group

Description:

H group stands for High concentration group. A single bolous of 20 ml ropivacaine 0.2% in ultrasound-guided femoral nerve block (FNB) before the TKA surgery, followed by continuous femoral nerve block (CFNB) using ropivacaine 0.2% (5 ml/h) for postoperative analgesia which started right after surgery. After surgery, all patients received multimodal analgesia of 200mg celecoxib every 12 hours. All subjects received anothother intravenous patient-controlled analgesia pump (IV-PCA pump), which included 50 mg morphine in 50 ml saline: bolus 2 mg; lock out time, 15 minutes.

Treatment:

Device: intravenous patient-controlled analgesia pump with morphine

Procedure: Continuous femoral nerve block

Procedure: ultrasound-guided femoral nerve block

L group

Experimental group

Description:

L group stands for low concentration group. A single bolous of 20 ml ropivacaine 0.1% in ultrasound-guided femoral nerve block (FNB) before the TKA surgery, followed by continuous femoral nerve block (CFNB) using ropivacaine 0.1% (5 ml/h) for postoperative analgesia which started right after surgery. All subjects received anothother intravenous patient-controlled analgesia pump (IV-PCA pump), which included 50 mg morphine in 50 ml saline: bolus 2 mg; lock out time, 15 minutes.

Treatment:

Device: intravenous patient-controlled analgesia pump with morphine

Procedure: Continuous femoral nerve block

Procedure: ultrasound-guided femoral nerve block

LD group

Experimental group

Description:

LD group stands for low concentration group with dexmedetomidine. A single bolous of 20 ml ropivacaine 0.1% plus 2 μg/kg dexmedetomidine in ultrasound-guided femoral nerve block (FNB) before the TKA surgery, followed by continuous femoral nerve block (CFNB) using ropivacaine 0.1% (5 ml/h) for postoperative analgesia which started right after surgery. All subjects received anothother intravenous patient-controlled analgesia pump (IV-PCA pump), which included 50 mg morphine in 50 ml saline: bolus 2 mg; lock out time, 15 minutes.

Treatment:

Drug: Dexmedetomidine

Device: intravenous patient-controlled analgesia pump with morphine

Procedure: Continuous femoral nerve block

Procedure: ultrasound-guided femoral nerve block