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Upper Limb InjuryNCT06428461

Evaluation of Supraclavicular Brachial Plexus Blocks at Various Volumes: Impact on Optic Nerve Sheath Diameter

A study testing Supraclavicular brachial plexus block, Measurement of Optic Nerve Sheath Diameter (ONSD) Using B-Mode Ultrasound and Assessment of Peripheral Nerve Block Success Using Perfusion Index Measurement in people with Upper Limb Injury and Intracranial Pressure Increase, run by Pamukkale University at 1 site in Turkey (Türkiye).

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial summary

This study aimed to evaluate the anesthesia adequacy, side effects, and complication rates, as well as the postoperative pain relief effectiveness of supraclavicular brachial plexus blocks administered at different volumes under ultrasound guidance. Read more about this study

Who is it for?
Ages 18 to 50 years
What is being tested?
Supraclavicular brachial plexus block, Measurement of Optic Nerve Sheath Diameter (ONSD) Using B-Mode Ultrasound and Assessment of Peripheral Nerve Block Success Using Perfusion Index Measurement
Could I receive a placebo?
No, everyone receives an active treatment
How many people
64 participants
Where
1 siteTurkey (Türkiye)
Study dates
20 May 2024to 10 Apr 2025
Phase
Interventional
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 to 50 years
  • All sexes
  • No healthy volunteers
  • Adult

Who may be able to join

  • Patients aged between 18 and 50, of both genders, with planned surgery on the finger, wrist, elbow joint, and distal region, and classified as ASA I-II, will be included in the study. In this study, patients will be informed about the anesthesia method and the tests to be conducted, and those who consent will be asked to sign an informed consent form as voluntary participants.

Who cannot join

  • Patients who do not accept the procedures and tests
  • Those with diseases that may cause increased intracranial pressure
  • Patients with severe heart failure
  • Patients with second or third degree atrioventricular block
  • Patients with unstable angina history
  • Patients with COPD and chronic asthma
Show all 15Show fewer
  • Patients with a history of myocardial infarction (MI) within the last 6 weeks
  • Patients with a heart rate below 50 beats/min
  • Patients with systolic blood pressure below 90 mmHg
  • Patients with liver failure
  • Patients with kidney failure
  • Patients for whom supraclavicular block anatomically cannot be performed
  • Those with neurological or psychological diseases that make it difficult to assess the tests
  • Patients allergic to any of the study drugs
  • Pregnant women

Trial locations and contacts

1 site in 1 country.

Turkey (Türkiye)1 site

  • Pamukkale University

    Denizli, Pamukkale, 20020

Other trials in Turkey (Türkiye)

About this study

Official title: Evaluation of Supraclavicular Brachial Plexus Blocks at Different Volumes Under Ultrasound Guidance in Upper Extremity Surgery and Their Impact on Optic Nerve Sheath Diameter

This study aimed to evaluate the anesthesia adequacy, side effects, and complication rates, as well as the postoperative pain relief effectiveness of supraclavicular brachial plexus blocks administered at different volumes under ultrasound guidance. Additionally, the investigators utilized ultrasound to measure optic nerve sheath diameters and investigated their relationship with intracranial pressure across varying block volumes.

Read the detailed description

Regional anesthesia involves temporarily blocking nerve transmission and pain sensation in specific areas of the body without causing loss of consciousness. Regional anesthesia techniques include peripheral nerve blocks (PNB), topical anesthesia, infiltration anesthesia, regional intravenous anesthesia (RIVA), and neuroaxial blocks (spinal and epidural anesthesia).

Brachial plexus blocks are among the most commonly used regional anesthesia methods within peripheral nerve block applications. Peripheral nerve blocks of the upper extremity can be used either alone for surgical anesthesia or added to general anesthesia for postoperative pain control. Brachial plexus blocks can be performed using various approaches including interscalene, supraclavicular, infraclavicular, and axillary approaches.

The supraclavicular block aims to effectively control pain through a procedure targeting the shoulder and upper extremity nerves known as the brachial plexus. Complications of supraclavicular blocks may include pneumothorax secondary to lung trauma, hoarseness due to ipsilateral recurrent laryngeal nerve blockade, Horner syndrome due to stellate ganglion blockade, and hemidiaphragmatic paralysis due to phrenic nerve blockade. The incidence and severity of these complications are reduced with the use of ultrasound (USG) guidance and low-volume techniques.

Intracranial pressure (ICP) refers to the pressure formed by the brain and spinal fluid, tissues, and blood surrounding the brain and spinal cord. Normally ranging between 5-15 mmHg, this pressure is critical for brain function and circulation. Abnormal increases in intracranial pressure can lead to intracranial hypertension, with main causes including brain tumors, edema, head trauma, brain aneurysms, intracranial hemorrhage, and issues related to the production and drainage of cerebrospinal fluid. External ventricular drainage (EVD) catheterization is the gold standard method for evaluating increased intracranial pressure. Measurement of optic nerve sheath diameter (ONSD) has been described as a valuable diagnostic method in clinical applications for evaluating intracranial pressure.

Observational studies have shown that in cervical sympathetic blocks and interscalene blocks, indirect increases in intracranial pressure can be demonstrated through ultrasound (USG) measurements of optic nerve sheath diameter. It has been shown that hemidiaphragmatic paralysis due to ipsilateral phrenic nerve involvement, which is frequently seen in interscalene brachial plexus blocks, also occurs in supraclavicular brachial plexus blocks in a volume-dependent manner. There are studies in the literature on supraclavicular block applications with different volumes and doses. However, the investigators have not come across a study evaluating the clinical outcomes of optic nerve sheath diameter measurement along with anesthesia quality, side effects, and complications in ultrasound-guided supraclavicular blocks at different volumes.

In this study, the investigators aimed to evaluate the anesthesia adequacy, side effects, and complication rates, as well as the postoperative analgesic efficacy of supraclavicular brachial plexus blocks performed at different volumes in our clinical practice under ultrasound guidance. Additionally, the investigators aimed to measure optic nerve sheath diameters with ultrasound and establish their relationship with intracranial pressure according to these different volumes.

Being tested
Supraclavicular brachial plexus block, Measurement of Optic Nerve Sheath Diameter (ONSD) Using B-Mode Ultrasound, Assessment of Peripheral Nerve Block Success Using Perfusion Index Measurement, End-Tidal Carbon Dioxide (EtCO2) Measurement
Keywords
Supraclavicular brachial plexus block, Intracranial pressure, Optic nerve sheath diameter
Medical subject headings
Arm Injuries, Intracranial Hypertension

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Supraclavicular brachial plexus blockProcedure or surgery

    A supraclavicular brachial plexus block will be performed under ultrasound guidance. The patient will be taken to the preoperative block room, positioned supine with the bed elevated at a 30° angle, and the head turned away from the arm being blocked. To avoid intraneural injection, the block will use both ultrasound and a nerve stimulator (Plexygon, Vygon-Italy) with a 22G 50 mm 20° stimulating needle (Echoplex, Braun-France). A low-frequency ultrasound probe will be placed above the clavicle to visualize the subclavian artery and vein. Using an in-plane approach, the needle will be inserted laterally to medially from the mid-clavicular point through the skin and subcutaneous tissue. Under ultrasound guidance, the needle will be advanced towards the anatomical corner where the brachial plexus and subclavian artery are adjacent (corner pocket), and a local anesthetic agent will be injected to perform the block.

  • Measurement of Optic Nerve Sheath Diameter (ONSD) Using B-Mode UltrasoundDevice

    Before the block, both eyes will be measured for optic nerve sheath diameter (ONSD) using B-mode ultrasound (USG) with a GE LOGIQ E device. The patient will be supine with the bed elevated at a 30° angle, eyes closed, and a protective barrier applied. Both globes will be filled with water-soluble ultrasound gel, and imaging will be done with a 7.5 MHz linear probe at a 7 cm depth. For transverse ONSD measurement, the probe will be placed transversely in the coronal plane, with the marker notch pointing right. When the optic nerve entry into the globe is clear, transverse ONSD will be measured 3 mm below. For sagittal measurement, the probe will be placed sagittally in the coronal plane, with the marker notch pointing towards the body. Sagittal ONSD will be measured 3 mm below the entry point. Both internal and external diameters of the optic nerve sheath will be measured in transverse and sagittal planes, and the transverse diameter of the globe will also be measured.

  • Assessment of Peripheral Nerve Block Success Using Perfusion Index MeasurementDevice

    Investigator plan to measure the Perfusion Index (PI) as an objective method for determining the success of peripheral nerve blocks, different from traditional tests. PI is an indicator of peripheral perfusion that can be continuously measured non-invasively with a pulse oximeter. PI represents the ratio of pulsatile blood flow to non-pulsatile blood flow in peripheral tissue. The Mindray uMEC 12 device will be used for this measurement.

  • End-Tidal Carbon Dioxide (EtCO2) MeasurementDevice

    End-tidal carbon dioxide (EtCO2) measurement: The Medtronic Capnostream 35 device will be used for EtCO2 measurements. All patients will receive oxygen support at a rate of 1-2 L/min. If peripheral oxygen saturation falls below 95%, oxygen support will be increased to 3-6 L/min via nasal cannula.

Study groups in NCT06428461
Study groupRoleWhat they receive
Total of 15 mL.Active comparatorFor the control group, we plan to use a mixture of 7.5 mL of 0.5% bupivacaine (BUVİCAİNE®) and 7.5 mL of 2% prilocaine (PRİLOC®) for a total of 15 mL. single shot supraclavicular brachial plexus block.
Receives: Procedure: Supraclavicular brachial plexus block; Device: Measurement of Optic Nerve Sheath Diameter (ONSD) Using B-Mode Ultrasound; Device: Assessment of Peripheral Nerve Block Success Using Perfusion Index Measurement; Device: End-Tidal Carbon Dioxide (EtCO2) Measurement
Total of 20 mL.Active comparatorFor the research group, we plan to use a mixture of 10 mL of 0.5% bupivacaine (BUVİCAİNE®) and 10 mL of 2% prilocaine (PRİLOC®) for a total of 20 mL.
Receives: Procedure: Supraclavicular brachial plexus block; Device: Measurement of Optic Nerve Sheath Diameter (ONSD) Using B-Mode Ultrasound; Device: Assessment of Peripheral Nerve Block Success Using Perfusion Index Measurement; Device: End-Tidal Carbon Dioxide (EtCO2) Measurement
Total of 25 mL.Active comparatorFor the research group, we plan to use a mixture of 12.5 mL of 0.5% bupivacaine (BUVİCAİNE®) and 12.5 mL of 2% prilocaine (PRİLOC®) for a total of 25 mL.
Receives: Procedure: Supraclavicular brachial plexus block; Device: Measurement of Optic Nerve Sheath Diameter (ONSD) Using B-Mode Ultrasound; Device: Assessment of Peripheral Nerve Block Success Using Perfusion Index Measurement; Device: End-Tidal Carbon Dioxide (EtCO2) Measurement
Total of 30 mL.Active comparatorFor the research group, we plan to use a mixture of 15 mL of 0.5% bupivacaine (BUVİCAİNE®) and 15 mL of 2% prilocaine (PRİLOC®) for a total of 30 mL.
Receives: Procedure: Supraclavicular brachial plexus block; Device: Measurement of Optic Nerve Sheath Diameter (ONSD) Using B-Mode Ultrasound; Device: Assessment of Peripheral Nerve Block Success Using Perfusion Index Measurement; Device: End-Tidal Carbon Dioxide (EtCO2) Measurement

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Optic nerve sheath diameter measured by ultrasonography

    Optic nerve sheath diameter will be measured using B-mode ultrasonography.

    Measured: Before block, After block 20 minutes, After block 60 minutes

Secondary outcomes (5)

  1. Perfusion index (PI)

    PI, an objective method different from traditional tests, to determine the success of peripheral nerve block. PI is an indicator of peripheral perfusion that can be measured continuously and non-invasively with a pulse oximeter. PI is the ratio of pulsatile blood flow to non-pulsatile blood flow in peripheral tissue. Its normal value ranges from 0.02 to 20. After peripheral nerve block, vasodilation occurs in the vessels due to sympathetic blockade, resulting in an increase in PI values, which occurs earlier than motor and sensory block. PI monitoring provides more objective results for evaluating the onset of the block. The cut-off value indicating that the block is successful is a PI increase to 3.03 times the baseline value 10 minutes after the block is administered.

    Measured: The PI values will be measured and recorded at 0, 2, 4, 6, 8, 10, 15, 20, and 25 minutes in both arms.

  2. Non-invazive end-tidal carbon dioxide (EtCO2)

    Non-invasive EtCO2 measurement is a method used to monitor the concentration of carbon dioxide (CO2) at the end of expiration.

    Measured: EtCO2 will be measured and recorded at 0, 10, 20, 30, 60 minutes, and at the end of surgery after the block is performed.

  3. Pinprick test

    The pinprick test is a clinical procedure used to evaluate sensory nerve function. A small, sharp object, such as a pin or needle, is gently pressed against the skin to assess the patient's ability to feel pain.

    Measured: The pinprick test will be evaluated 5 minutes after the block is performed and subsequently at 5-minute intervals, up to a maximum of 30 minutes. The results will be recorded throughout these evaluations.

  4. Modified Bromage Scale

    The Modified Bromage Scale is a clinical tool used to assess the degree of motor block in patients who have received regional anesthesia. The scale ranges from 0 to 3, with each level indicating a different degree of motor impairment:

    • 0: No motor block; full flexion of knees and feet.
    • 1: Partial motor block; able to move knees but not feet.
    • 2: Almost complete motor block; able to move feet only.
    • 3: Complete motor block; unable to move knees or feet.

    Measured: The Modified Bromage Scale will be evaluated 5 minutes after the block is performed and subsequently at 5-minute intervals, up to a maximum of 30 minutes. The results will be recorded throughout these evaluations.

  5. Verbal Pain Score

    The Verbal Pain Score is a subjective measure used to assess a patient's level of pain. Patients are asked to rate their pain on a scale from 0 to 10, where 0 indicates no pain and 10 represents the worst pain imaginable.

    Measured: The Verbal Pain Score will be assessed at the following intervals after surgery: immediately in the recovery room, at 1 hour, 2 hours, 4 hours, 6 hours, 12 hours, and 24 hours postoperatively.

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted24 May 2024
  2. Study start20 May 2024
  3. Primary completion3 Aug 2024
  4. Study completion10 Apr 2025

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Screening
Allocation
Randomised
Intervention model
Parallel groups
Model description
Four different volumes will be administered for the supraclavicular block: 1. For the control group, we plan to use a mixture of 7.5 mL of 0.5% bupivacaine (BUVICAINE-POLIFARMA-TEKIRDAG) and 7.5 mL of 2% prilocaine (PRILOC-VEM İlaç San. ve Tic. A.Ş. Kapaklı/TEKIRDAĞ) for a total of 15 mL. 2. For the research group, we plan to use a mixture of 10 mL of 0.5% bupivacaine and 10 mL of 2% prilocaine for a total of 20 mL. 3. For the research group, we plan to use a mixture of 12.5 mL of 0.5% bupivacaine and 12.5 mL of 2% prilocaine for a total of 25 mL. 4. For the research group, we plan to use a mixture of 15 mL of 0.5% bupivacaine and 15 mL of 2% prilocaine for a total of 30 mL. Glob axis and optic nerve sheath diameter measurements for both eyes will be re-measured and recorded using B-mode ultrasound at 20 and 60 minutes after the supraclavicular block.
Masking
Triple blind
Who is masked
Participant, Care provider, Outcomes assessor
Enrolment
64 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT06428461
Sponsor's protocol ID
PAU-ANEST-RHE-IC-01
Status last verified
Feb 2026
First submitted
14 May 2024
Last updated
3 Mar 2026
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No

Publications

  • Gundogdu O, Avci O. Evaluation of the Effect of Interscalene Brachial Plexus Block on Intracranial Pressure Using Optic Nerve Sheath Diameter and Internal Jugular vein Collapsibility Index. J Coll Physicians Surg Pak. 2022 Oct;32(10):1249-1254. doi: 10.29271/jcpsp.2022.10.1249.

    PubMed 36205266

  • Pansell J, Bell M, Rudberg P, Friman O, Cooray C. Optic nerve sheath diameter measurement by ultrasound: Evaluation of a standardized protocol. J Neuroimaging. 2022 Jan;32(1):104-110. doi: 10.1111/jon.12936. Epub 2021 Sep 23.

    PubMed 34555223

  • Hylkema C. Optic Nerve Sheath Diameter Ultrasound and the Diagnosis of Increased Intracranial Pressure. Crit Care Nurs Clin North Am. 2016 Mar;28(1):95-9. doi: 10.1016/j.cnc.2015.10.005. Epub 2015 Dec 23.

    PubMed 26873762

Questions about this trial

What is this clinical trial studying?

A study testing Supraclavicular brachial plexus block, Measurement of Optic Nerve Sheath Diameter (ONSD) Using B-Mode Ultrasound and Assessment of Peripheral Nerve Block Success Using Perfusion Index Measurement in people with Upper Limb Injury and Intracranial Pressure Increase, run by Pamukkale University at 1 site in Turkey (Türkiye).

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 1 inclusion and 15 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 3 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Turkey (Türkiye). Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Optic nerve sheath diameter measured by ultrasonography (time frame: Before block, After block 20 minutes, After block 60 minutes). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT06428461, which also lists 3 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 3 Mar 2026.

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