Retroclavicular Approach to Infraclavicular Block

Minimum Effective Volume of Bupivacaine 0.5% for Ultrasound-guided Retroclavicular Approach to Infraclavicular Brachial Plexus Block

Status

Completed

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT03472911

Enrollment

Registered

2018-03-21

Start date

2018-01-08

Completion date

2018-03-15

Last updated

2018-05-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Bupivacaine

Brief summary

In this study, the primary objective was to estimate the minimum effective volume of bupivacaine 0.5% resulting in successful block in 50% of patients (MEV50) for ultrasound-guided retroclavicular approach to infraclavicular brachial plexus block.

Detailed description

Two rules were used to stop the study. First stopping rule was a fixed-sample-size. The investigators used an up-and-down method to estimate the threshold for an all-or-none response for present study design. Therefore, for sample size calculation, the investigators applied the formula by Dixon and Massey, n=2(SD/SEM)2 (SD: standard deviation and SEM: standard error of mean). Second stopping rule included demonstration of minimum of five consecutive up-and-down sequences. On the basis of previous studies with similar binary outcomes, the investigators estimated that a priori a minimum of five negative-positive up-and down deflections was required to calculate MEV50.

Interventions

OTHERminimum effective volume

The determination of MEV50 and its 95% confidence interval (CI) was based on the staircase up-and-down method by Dixon and Massey.

Study design

Observational model

CASE_ONLY

Time perspective

PROSPECTIVE

Eligibility

Sex/Gender

ALL

Age

18 Years to 65 Years

Healthy volunteers

Inclusion criteria

* patients who received infraclavicular brachial plexus block for elective elbow, forearm, wrist, or hand surgery * American Society of Anesthesiologists class I, II or III

Exclusion criteria

* patients \<18 years old * \>65 years old * body mass index (BMI) \<20 or \>35 kg/m2 * inability to provide written informed consent * refusal of regional anesthesia * pregnancy * contraindication for regional anesthesia

Design outcomes

Primary

Measure	Time frame	Description
The minimum effective volume of bupivacaine 0.5% resulting in successful block in 50% of patients (MEV50)	30 minutes	The determination of MEV50 and its 95% confidence interval (CI) was based on the staircase up-and-down method by Dixon and Massey

Secondary

Measure	Time frame	Description
estimate the minimum effective volume in 95% of patients (MEV95).	30 minutes	To calculate the MEV95, data were analyzed using probit transformation and logistic regression.

Countries

Turkey (Türkiye)

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026