Lidocaine use in ultrasound-guided femoral nerve block: what is the minimum effective anaesthetic concentration (MEAC 90 )? †

Background: Effective pain control in Total knee arthroplasty (TKA) is important for optimizing the rehabilitation process in order to achieve patient satisfaction with a good functional outcome as well as reduce hospitalization duration and costs. Combined use of aesthetic with tramadol has been reported to achieve a longer duration of sensory and motor block. The aim of this study is to evaluate the quality and duration of postoperative analgesia produced by ultrasound guided femoral nerve block (FNB) by bupivacaine versus (bupivacaine & tramadol) in patients undergoing total knee arthroplasty under spinal anesthesia. Methods: This prospective randomized controlled double blinded study was carried out on 60 patients aged above 50 years; American Society of Anesthesiologists physical status (ASA) I-III scheduled for total knee arthroplasty under spinal anesthesia. Patients were randomized to one of two equal groups: Group I control (C): received FNB with 30 ml 0.25% bupivacaine. Group II tramadol (T): received FNB with 30ml 0.25% bupivacaine and 100 mg tramadol. Results: Postoperative heart rate was significantly increased in group C than group T at 8h, 12h, 16h and 24h. Postoperative mean arterial blood pressure was significantly increased in group C than group T at 6h, 8h, 12h, 16h and 24h. There were 30 (100%) patients required rescue analgesia in group C and 19 (63.33%) patients in group T which was increased significantly in group C than group T. The time to first analgesic requirement was significantly decreased in group C than group T. Total morphine consumption was increased significantly in group C than group T. VAS was increased significantly in group C than group T at 6, 8, 12, 16 and 24 hours. Adverse effects were insignificantly different between both groups. Conclusion: Adding tramadol (100 mg) to 0.25% bupivacaine (to a volume of 30 ml) during US guided FNB of TKA under spinal anesthesia was associated with better postoperative analgesia when compared with 0.25% bupivacaine alone.

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Minimum Effective Concentration of Bupivacaine in Ultrasound-Guided Femoral Nerve Block after Arthroscopic Knee Meniscectomy: A Randomized, Double-Blind, Controlled Trial

January 2018 - Pain Physician ◽

10.36076/ppj/2016.19.e79 ◽

2016 ◽

Vol 1;19 (1;1) ◽

pp. E79-E86

Author(s):

Rioko K. Sakata

Keyword(s):

Pain Intensity ◽

Nerve Block ◽

Femoral Nerve Block ◽

Controlled Trial ◽

Femoral Nerve ◽

Pain Intensity Score ◽

Ultrasound Guided ◽

Double Blind ◽

Intensity Score ◽

Arthroscopic Knee

Background: Adequate analgesia is important for early hospital discharge after meniscectomy. A femoral nerve block may reduce the need for systemic analgesics, with fewer side effects; however, motor block can occur. Ultrasound-guided femoral nerve block may reduce the required local anesthetic concentration, preventing motor block. Objective: The primary objective of this study was to determine the lowest effective analgesic concentration of bupivacaine in 50% (EC50) and in 90% (EC90) of patients for a successful ultrasoundguided femoral nerve block in arthroscopic knee meniscectomy. Study Design: This was a prospective, randomized, double-blind, controlled trial. Settings: This study was conducted at Hospital São Domingos. Methods: A total of 52 patients undergoing arthroscopic knee meniscectomy were submitted to ultrasound-guided femoral nerve block using 22 mL bupivacaine. The bupivacaine concentration given to a study patient was determined by the response of the previous patient (a biased-coin design up–down sequential method). If the previous patient had a negative response, the bupivacaine concentration was increased by 0.05% for the next case. If the previous patient had a positive response, the next patient was randomized to receive the same bupivacaine concentration (with a probability of 0.89) or to have a decrease by 0.05% (with a probability of 0.11). A successful block was defined by a numerical pain intensity scale score < 4 (0 = no pain; 10 = worst imaginable pain) in 3 different evaluations. If the pain intensity score was ≥ 4 (moderate or severe pain) at any time, the block was considered failed. General anesthesia was induced with 30 μg/kg alfentanil and 2 mg/ kg propofol, followed by propofol maintanance, plus remifentanil if needed. Postoperative analgesia supplementation was performed with dipyrone; ketoprofen and tramadol were given if needed. Data Measurements: The following parameters were evaluated: numerical pain intensity score, duration of analgesia, supplementary analgesic dose in 24 hours, and need for intraoperative remifentanil. Results: The EC50 was 0.160 (95% CI: 0.150 – 0.189), and EC90 was 0.271 (95% CI: 0.196 – 0.300). There was no difference in numerical pain intensity score for the different concentrations of bupivacaine. A successful block was achieved in 45 patients, with no difference according to bupivacaine concentration. Time to first analgesic supplementation dose was longer for bupivacaine concentrations ≥ 0.3% (543.8 ± 283.8 min.), compared to 0.25% (391.3 ± 177.8 min.) and < 0.25% (302.3 ± 210.1 min.). There were no differences in supplementary analgesic dose in 24 hours nor in the use of intraoperative remifentanil according to bupivacaine concentration. Limitations: The analgesic effect was measured only during the first 2 hours. Conclusions: Bupivacaine EC50 for ultrasound-guided femoral nerve block was 0.160 (95% CI: 0.150 – 0.189), and EC90 was 0.271 (95% CI: 0.196 – 0.300). Key words: Postoperative analgesia, femoral block, ultrasound-guided, bupivacaíne minimum concentration, arthroscopic meniscectomy

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Ultrasound-guided regional anesthesia: feasibility and effectiveness of teaching via telesimulation in Ethiopia

Regional Anesthesia and Pain Medicine ◽

10.1136/rapm-2020-102394 ◽

2021 ◽

pp. rapm-2020-102394

Author(s):

Monica Liu ◽

Margaret Salmon ◽

Rene Zaidi ◽

Arun Nagdev ◽

Finot Debebe ◽

...

Keyword(s):

Regional Anesthesia ◽

Nerve Block ◽

Rating Scale ◽

Femoral Nerve Block ◽

Femoral Nerve ◽

House Staff ◽

Global Rating Scale ◽

Global Rating ◽

Ultrasound Guided ◽

Post Test

BackgroundAcute pain management in resource-poor countries remains a challenge. Ultrasound-guided regional anesthesia is a cost-effective way of delivering analgesia in these settings. However, for financial and logistical reasons, educational workshops are inaccessible to many physicians in these environments. Telesimulation provides a way of teaching across distance by using simulators and video-conferencing software to connect instructors and students worldwide. We conducted a prospective study to determine the feasibility of ultrasound-guided regional anesthesia teaching via telesimulation in Ethiopia.MethodsEighteen Ethiopian orthopedic and emergency medicine house staff participated in telesimulation teaching of ultrasound-guided femoral nerve block. This consisted of four 90-min sessions, once per week. Week 1 consisted of a precourse test and a presentation on aspects of performing a femoral nerve block, weeks 2 and 3 were live teaching sessions on scanning and needling techniques, and in week 4, the house staff undertook a postcourse test. All participants were assessed using a validated Global Rating Scale and Checklist.ResultsParticipants were provided with a validated checklist and global rating scale as a pretest and post-test. The participants showed significant improvement in their test scores, from a total mean of 51% in the pretest to 84% in their post-test.ConclusionsTeaching ultrasound-guided regional anesthesia of the femoral nerve remotely via telesimulation is feasible. Telesimulation can greatly improve the accessibility of ultrasound-guided regional anesthesia teaching to physicians in remote areas.

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Ultrasound-Guided Femoral Nerve Block

Perioperative Diagnostic and Interventional Ultrasound ◽

10.1016/b978-1-4160-3356-1.10018-4 ◽

2008 ◽

pp. 153-158

Author(s):

Brian D. O'Donnell ◽

Dominic Harmon ◽

Henry P. Frizelle

Keyword(s):

Nerve Block ◽

Femoral Nerve Block ◽

Femoral Nerve ◽

Ultrasound Guided

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Ultrasound-Guided Continuous Femoral Nerve Block with Dexmedetomidine Combined with Low Concentrations of Ropivacaine for Postoperative Analgesia in Elderly Knee Arthroplasty

Medical Principles and Practice ◽

10.1159/000500261 ◽

2019 ◽

Vol 28 (5) ◽

pp. 457-462 ◽

Cited By ~ 2

Author(s):

Xiao-Ying Zhao ◽

Er-Fei Zhang ◽

Xiao-Li Bai ◽

Zi-Jian Cheng ◽

Peng-Yun Jia ◽

...

Keyword(s):

Elderly Patients ◽

Nerve Block ◽

Knee Arthroplasty ◽

Postoperative Analgesia ◽

Femoral Nerve Block ◽

Femoral Nerve ◽

Ultrasound Guided ◽

Low Concentrations ◽

Functional Exercise ◽

Continuous Femoral Nerve Block

Objectives: This study aims to investigate the clinical effect of dexmedetomidine (DEX) combined with low concentrations of ropivacaine in ultrasound-guided continuous femoral nerve block for postoperative analgesia in elderly patients with total knee arthroplasty (TKA). Materials and Methods: Patients were divided into three groups: group C, group D1, and group D2. For postoperative analgesia, patients in group C were given 0.15% ropivacaine, patients in group D1 were given 0.15% ropivacaine + 0.02 μg × kg–1 × h–1 DEX, and patients in group D2 were given 0.15% ropivacaine + 0.05 μg × kg–1 × h–1 DEX. The visual analogue scores in the resting state, active state (AVAS), and passive functional exercise state (PVAS), degree of joint bending, and Ramsay scores were recorded. Results: The Ramsay scores were significantly higher, AVAS scores were significantly lower, PVAS scores were significantly decreased, the degree of joint bending was significantly higher, and the time to the first postoperative ambulation was shorter in groups D1 and D2 than group C. Furthermore, the time to the first postoperative ambulation was shorter in group D2 than in group D1, patients in groups D1 and D2 were more satisfied than patients in group C, and patients in group D2 were more satisfied than patients in group D1. Conclusion: The protocol of 0.05 μg × kg–1 × h–1 of DEX combined with 0.15% ropivacaine in ultrasound-guided continuous femoral nerve block for postoperative analgesia in elderly patients with TKA provides a better analgesic effect than without DEX performance.

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