Analgesic Efficacy of Saphenous Nerve Block in Total Knee Replacement

Phase 4

Completed

• Conditions: Post Operative Pain

• Registration Number: NCT01991288
• Lead Sponsor: Cork University Hospital

Brief Summary

We hypothesize that preoperative saphenous nerve block (SNB) in combination with periarticular local infiltration provides better post operative pain relief (POPR) profile as compared to local infiltration alone

Detailed Description

Introduction:

Local infiltration analgesia (LIA) is considered acceptable after total knee replacements (TKR) in terms of analgesia, ease of performance, early mobilization and early hospital discharge . Continuous femoral nerve block has been used to enhance post op pain relief (POPR) for TKR but at the expense of motor blockade . A Sub sartorial approach to saphenous nerve block (SNB) spares the motor block . To date the role of saphenous nerve block for POPR in TKR has not been evaluated.

Methodology:

In order to test this hypothesis, we proposed to carry out a prospective randomized controlled double blinded (surgeon and assessor) trial study. With institutional ethics approval and having obtained written informed consent from each patient, 20 ASA 1 - 3 patients scheduled to undergo TKR under spinal anesthesia +/- sedation were allocated to one of two groups i.e. Group (SNB): patients receiving SNB sub sartorial approach and Group (NSNB): patients not receiving SNB.

Group allocation was determined using computer generated random number tables. Sealed envelopes were opened on the day of the surgery by the attending anesthetist responsible for the care of the recruited patient.

Postoperative period:

Patients were then assessed for pain at rest and on movement on arrival in recovery and then at 6 , 12 and 24 hrs. Visual analogue scale on a 10 cm straight line was used to assess postoperative pain scores as predictive value of post operative analgesia on rest and movement i.e passive flexion of knee to 30 degree . Patients were assessed for any motor block by using maximum tolerable range of active knee flexion (MKF) and maximum range of straight leg raise(MSLR) on arrival in recovery and at 6, 12 and 24 hrs. All patients received regular paracetamol 1g 6 hourly, diclofenac 75 mg 12 hourly, oxycontin 10-20 mg ( depending on age) 12 hourly and oxynorm 10 mg as rescue analgesia.

Study Timeline

• Study Start: 2012-11
• Primary Completion: 2013-05
• Study Completion: 2013-07
• Status Verified: 2013-11
• Study First Submitted: 2013-11-17
• Study First Submitted QC: 2013-11-21
• Last Update Submitted: 2013-11-21
• Study First Posted: 2013-11-25
• Last Update Posted: 2013-11-25

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 20

Inclusion Criteria

American Society of Anaesthesia (ASA) Grade I-lll patients Undergoing elective Total Knee Arthroplasty Patients able to consent and understand all the components of the study.

Exclusion Criteria

Demented patients Patients having bilateral Knee Replacements Patients unable to comprehend the use of pain scales Allergy to any of the medications used in the study Renal dysfunction Coagulation disorders Peptic ulcer disease precluding use of non-steroidal anti-inflammatory drugs (NSAIDs) Patients unable to use regular opioid medication Any chronic pain condition other than osteoarthritis of the knee.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Pain on movement at 24 hours time point post operatively	24 hours hours time point

Secondary Outcome Measures

Name	Time	Method
6 Minute walk test	At 24 hours Post block Conduction
pain on movement at 6 and 12 hour time point	6 and 12 hours time points
pain at rest at 6, 12 and 24 hours time points	6, 12 and 24 hours time points
Maximum Knee Flexion at 6, 12 and 24 hours time points	6, 12 and 24 hours time points
Maximum Straight Leg Raise Test at 6, 12 and 24 hours time points	6, 12 and 24 hours time points
Time to First request for rescue analgesia	24 hours
Cumulative Opioid consumption in 24 hours	24 hours
Cumulative opioid consumption till discharge	till discharge time

Trial Locations

Locations (1)

Dept. of Anaesthesia & Intensive Care Unit, Cork University Hospital; 🇮🇪 Cork, Ireland