MEV 90 of 0.5% Ropivacaine In Infraclavicular Blocks (MEV90ROPI)

Minimum Effective Volume of 0.5% Ropivacaine for Ultrasound-Guided Infraclavicular Block

Nerve blocks are routinely performed perioperatively to provide anesthesia and analgesia for various surgical procedures on the upper limb. These blocks are performed with the aid of an ultrasound machine to improve the success rate. Below the clavicle approach to these nerves is used for surgeries below the elbow, forearm and hand efficiently.

Ultrasound guidance for such blocks allows direct visualisation of the needle and the spread of the freezing medication (local anesthetic) in real-time therefore reducing complications and improving success rates of blocks. It may be possible that a smaller volume of local anesthetic in this setting may allow effective anesthesia while lowering the adverse effects. The aim of this study is to find out the lowest volume of the local anesthetic that will be effective in blocking the nerves adequately.

Study Overview

• Status: Unknown
• Conditions: Infraclavicular Brachial Plexus Block
• Intervention / Treatment: Drug: Dose of ropivacaine

Detailed Description

This is a dose finding study. Volume assignment of ropivacaine will be carried out using a Biased Coin Design up and down method. In this method, the volume of local anesthetic (ropivacaine) administered to each patient will depends on the response of the previous patient. In the event of block failure, the next subject will receive an additional 2 mL of volume compared with the previous patient. In the event of block success, the next patient will receive either the same volume as the last patient or a 2 mL reduction in volume (per the biased coin design with a probability of the same volume being 0.9 and lower volume being 0.1). The first patient in the study will receive 30 mL and depending on the block success, the volume of the next block will be increased or decreased. The biased coin design is well described and established in other minimum volume studies.

All patients will have the block in the block room with standard monitoring (non-invasive blood pressure, pulse-oximetry, electrocardiogram) and mild sedation with midazolam and fentanyl. All blocks will be performed by staff anesthesiologists with a subspecialty in regional anesthesia and who work routinely in the block room or by a resident or fellow who is directly supervised by one of these staff anesthesiologist.

There will be two follow up telephone call to all patients enrolled in this study 24 hours post block insertion and one at 7 days to discuss length of block duration, any postoperative nausea/vomiting, any ongoing numbness or tingling, and overall satisfaction with the block. The participants will be informed of this phone call as part of the consent process and their telephone number will be confirmed.

• Study Type: Interventional
• Enrollment (Anticipated): 55
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Shalini Dhir, MD, FRCPC; Phone Number: 64219 +1 519 646 6000; Email: shalini.dhir@sjhc.london.on.ca

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Adults aged 18 to 80 years
• Amercian Society of Anesthesia physical status I, II, III
• Patients undergoing upper limb surgeries (with/without sedation)
• Ability to provide written informed consent

Exclusion Criteria:

• Patient refusal
• Known history of sensitivity or contraindications to study drugs
• Pregnant patients
• Infection at the site of administration of block
• Significant blood coagulation disorders
• Neurological deficits involving brachial plexus
• Patients on any medication which is known to have drug interactions with the study drugs
• Patients who receive general anesthesia/ narcotic supplements

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Ropivacaine dosage; Dose finding study - The volume of 0.5% ropivacaine used to achieve surgical anesthesia in infraclavicular brachial plexus block	Drug: Dose of ropivacaine; Biased coin design up and down dose finding study of 0.5% ropivacaine to achieve a successful infraclavicular brachial plexus block

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
ED90 of 0.5% Ropivacaine	Volume used to achieve sensory and motor blockade (surgical anesthesia)	30 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Surgical anesthesia	Sensory and motor blockade tested using pin prick sensation ( 0 - normal sensation and can feel pin-prick, 1 - touch only, 2 - no sensation of touch or pinprick) and motor function of the ulnar, radial and median nerves.	30 minutes

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Duration of sensory anesthesia	Duration of analgesia - time from administration of block to Visual analogue scale score more than 4 or patient request for first analgesic dose	8 to 10 hours
Complications during block placement	Incidence of paresthesia during needle insertion, vascular or pleural puncture	30 minutes
Postoperative complications 24 hours and 7 days	Presence or absence of tingling, numbness, weakness of limb will be noted. Patient satisfaction as satisfied or unsatisfied will be noted.	24 hours and 7 days

Collaborators and Investigators

• Sponsor: Lawson Health Research Institute

Study record dates

Study Major Dates

• Study Start (Anticipated): January 1, 2019
• Primary Completion (Anticipated): June 1, 2020
• Study Completion (Anticipated): June 1, 2020

Study Registration Dates

• First Submitted: January 9, 2019
• First Submitted That Met QC Criteria: January 29, 2019
• First Posted (Actual): January 31, 2019

Study Record Updates

• Last Update Posted (Actual): January 31, 2019
• Last Update Submitted That Met QC Criteria: January 29, 2019
• Last Verified: January 1, 2019

More Information

Terms related to this study

• Keywords: Ropivacaine; Infraclavicular block; Brachial plexus block
• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Central Nervous System Depressants; Peripheral Nervous System Agents; Sensory System Agents; Anesthetics; Anesthetics, Local; Ropivacaine
• Other Study ID Numbers: 112062

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No