Clinical trial NCT02086643: The Retroclavicular Approach for Regional Anesthesia of the Upper Limb in Obese Patients
Official title: The Retroclavicular Approach for Regional Anesthesia of the Upper Limb in Patients With BMI ≥ 30 kg/m2 : A Descriptive Study
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE4
Conditions: Overweight
Keywords: Infraclavicular block
Brachial Plexus
Retroclavicular Approach
Complications of retroclavicular approach
Success of retroclavicular approach
Obese Patients
Obesity and Anesthesia
Lead sponsor: Université de Sherbrooke
Sponsor class: OTHER
First posted: 2014-03-13
Enrollment: 32
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: SUPPORTIVE_CARE

Brief summary: The goal of this study is to determine the success rate of the retroclavicular approach for the anesthesia of the upper limb in the obese patient population (BMI ≥ 30 kg/m2)

Detailed description: Classic infraclavicular approach of the brachial plexus involves a needle puncture below the clavicle and advancing the needle with a 45-60 degree angle from cephalad to caudad. The aim is to advanced the block needle posterior to the axillary artery and to deposit the local anesthetic at that point, near the posterior cord. A "U" shaped spread around the artery should ensure distribution around all three cords. Ultrasound guidance is highly recommended and neurostimulation is optional.

The retroclavicular approach is a variant to this classical technique. Ultrasound probe is positioned initially below the clavicle in a manner similar to the classic approach but is then rotated in a clockwise fashion (right arm) or counter-clockwise fashion (left arm) for about 25-35 degrees. The puncture site is just behind the clavicle at the most lateral point available. If initial entry point is optimal, needle direction is then parallel to ultrasound probe. The final aim and position of block needle is identical to classical approach. Entry point ensures a parallel alignment of the needle and the ultrasound beam, thus enabling almost perfect visualization of both artery, cords and block needle. This is turn optimizes safety, rapidity of technique, efficiency and efficacy.

It is recognized that regional anesthesia is more difficult to perform in obese patients. Anatomic landmarks are harder to localize in this population and ultrasound guidance is more difficult because of the attenuation of the ultrasound beam by adipose tissue. The complication rate of regional techniques is also reported to be higher in the obese patient population.

Since the retroclavicular variant of the infraclavicular approach for the anesthesia of the brachial plexus offers a better needle visualisation, we believe that this technique can be used successfully in the obese patient population with a low complication rate.

Eligibility criteria: Inclusion Criteria:

* Elective or Urgent Surgery of the hand, wrist or forearm
* 18 years and older
* Ability to consent
* American Society of Anesthesiologists class 1 to 3
* BMI ≥ 30 kg/m2

Exclusion Criteria:

* Infection at the site of infection
* Abnormal anatomy at the site of infection
* Coagulopathy
* Severe Pulmonary Disease
* Preexisting neurological symptom(s) in the operated arm
* Pregnant patients
* Patients weighing less than 50 kg
* Allergy to amide type local anesthetics

Primary outcomes:
measure: Surgery completion under regional block
timeFrame: Success is defined at end of surgery for which block was done, generally within 1 to 3 hours after block is performed
Secondary outcomes:
measure: Sensitive block progression
timeFrame: Assessed 10, 20 and 30 minutes after block completion
measure: Motor Block Progression
timeFrame: Assessed 10, 20, 30 minutes after the block
measure: Technique duration
timeFrame: Time required in seconds for the retroclavicular block technique completion, generally under 15 minutes
measure: Needle visualization
timeFrame: Assessed after study completion, once all 30 patients will have been completed. Assessment will take place in the first 4 weeks after all 30 patients have been recruited
measure: Patient discomfort
timeFrame: Assessed 1 minute after block completion
measure: Patient satisfaction
timeFrame: Assessed 48 hours after the block
measure: Late Complication Rate
timeFrame: Assessed 48 hours after the block
measure: Duration of the Block's Effects
timeFrame: Assessed 48 hours after the block
measure: Use of narcotic for tourniquet pain
timeFrame: Assessed while surgery in under process
measure: Rate of Neurostimulation Usage
timeFrame: Assessed during the block
measure: Failure because of poor ultrasound visualization
timeFrame: Assessed during the performance of the nerve block
measure: Early Complication Rate
timeFrame: Assessed during block performance, throughout surgery and in the PACU. Generally during a period of 4-6 hours after block completion
Other outcomes:
Locations:
city: Sherbrooke
country: Canada
facility: Centre hospitalier universitaire de Sherbrooke (CHUS)
state: Quebec
Study officials:
affiliation: Université de Sherbrooke
name: Pablo Echave, M.D.
role: PRINCIPAL_INVESTIGATOR
References: