The MEV of 0.5% Ropivacaine in Ultrasound-guided SASIS-FICB

Study Overview
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Brief Summary
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The Aim of This Study is to Determine the Minimum Effective Volume of Local Anesthetic (Ropivacaine 0.5%) Required to Produce an Effective Ultrasound-guided Supra-anterior Superior Iliac Spine Fascia Iliaca Compartment Block（SASIS-FICB） for Surgical Anesthesia in 90% of Patients Scheduled for Elective Surgery of One Lower Limbs.

Detailed Description
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The study is based on biased coin design, and the volume of Local Anesthetic (Ropivacaine 0.5%) for the next patient is determined by the result of the last one. In the case of block failure, the volume will be increased by 2.5ml. Conversely, block success will result in either a reduction in volume by 2.5ml (probability 11%) or no change in volume (probability 89%). A blinded assistant will assess sensory and motor blockade in each nerve territory ( the femoral, obturator and lateral femoral cutaneous nerves) at 5-min intervals up to 30 min after completion of the block. Finally, MEV90 is calculated by isotonic regression.

Official Title
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The Minimum Effective Volume (MEV) of 0.5% Ropivacaine in Ultrasound-guided Supra-anterior Superior Iliac Spine Fascia Iliaca Compartment Block (SASIS-FICB)

Conditions
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Nerve Block

Intervention / Treatment
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* Procedure: Ultrasound-guided Supra-anterior Superior Iliac Spine Fascia Iliaca Compartment Block (SASIS-FICB) with 0.5% ropivacaine
* Drug: different volume of 0.5% ropivacaine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients undergoing hip/knee surgery Exclusion Criteria: age <18 years body mass index >35 inability to consent to the study allergy to local anesthetics a history of liver or renal insufficiency, coagulopathy clinical evidence of peripheral neuropathies, abnormalities of sensory or motor function of the FN, ON or LFCN.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Interventional Model Description: This is a dosing exploratory study.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: SASIS-FICB<br>All subjects will be enrolled in the experimental group and receive an Ultrasound-guided Supra-anterior Superior Iliac Spine Fascia Iliaca Compartment Block (SASIS-FICB) | Procedure: Ultrasound-guided Supra-anterior Superior Iliac Spine Fascia Iliaca Compartment Block (SASIS-FICB) with 0.5% ropivacaine<br>* all the patients received Ultrasound-guided Supra-anterior Superior Iliac Spine Fascia Iliaca Compartment Block (SASIS-FICB)<br>Drug: different volume of 0.5% ropivacaine<br>* According to the subject's response to the injection dose, the next subject will be injected with a different volume of the drug according to the preset rules<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The MEV90 of 0.5%Ropivacaine in Ultrasound-guided SASIS-FICBS | We prospectively recruited patients to receive different volumes of SASIS-FICB in accordance with the sequential trial rules of biased coins until 45 successful SASIS-FICB attempts were completed. MEV90 was calculated by isometric regression. | up to 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Minimum Effective volume, Ropivacaine, Fascia Iliaca Compartment Block