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AnalgesiaNCT05165498

Real-time Ultrasound Guidance for Thoracic Epidural Blocks

An observational study of Analgesia and Thoracic Tumors, run by University of Chile at 1 site in Chile.

Withdrawn

Withdrawn. The study stopped before anyone enrolled.

Official record
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Trial summary

Various modalities have been proposed for real-time confirmation of loss of resistance (LOR) for thoracic epidural blocks. With real-time ultrasound (US) guidance, the anesthesiologist attempts to visualize the sonographic advancement of the epidural needle and penetration of the epidural space (as detected by LOR)… Read more about this study

Who is it for?
Ages 18 to 80 years
Conditions the study is for
Analgesia, Thoracic Tumors, Abdomen Tumors
What is being tested?
Real-time ultrasound guidance for thoracic epidural catheter placement.
How many people
0 participants
Where
1 siteChile
Study dates
Jul 2027to Dec 2028
Phase
Observational
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 80 years
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Study population: Patients undergoing elective thoracic surgery, abdominal surgery, or suffering from rib fractures who will have placed a thoracic epidural catheter to manage their perioperative analgesia.

Who may be able to join

  • Age between 18 and 80 years
  • American Society of Anesthesiologists classification 1-3
  • Body mass index between 20 and 35 (kg/m2)

Who cannot join

  • Adults who are unable to give their own consent
  • Sepsis (assessed by history and physical examination and, if deemed clinically necessary, by blood work up i.e. leukocytosis, increased c-reactive protein, increased procalcitonin)
  • Coagulopathy (assessed by history and physical examination and, if deemed clinically necessary, by blood work up i.e. platelets ≤ 100, International Normalized Ratio ≥ 1.4 or prothrombin time ≥ 50)
  • Allergy to local anesthetics (LAs)
  • Prior surgery in the thoracic spine

Trial locations and contacts

1 site in 1 country.

Chile1 site

  • Hospital Clínico Universidad de Chile

    Santiago, Metropolitan, 8380456

Other trials in Chile

About this study

Official title: Reliability of Real-time Ultrasound Guidance as an Adjunct to Loss of Resistance for Thoracic Epidural Blocks

Various modalities have been proposed for real-time confirmation of loss of resistance (LOR) for thoracic epidural blocks. With real-time ultrasound (US) guidance, the anesthesiologist attempts to visualize the sonographic advancement of the epidural needle and penetration of the epidural space (as detected by LOR)

This observational study is set out to confirm the reliability of real-time ultrasound guidance as an adjunct to LOR for thoracic epidural blocks.

Being tested
Real-time ultrasound guidance for thoracic epidural catheter placement.
Keywords
Thoracic peridural, Ultrasound-guided
Medical subject headings
Agnosia, Abdominal Neoplasms, Rib Fractures

What participants receive

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

  • Real-time ultrasound guidance for thoracic epidural catheter placement.Procedure or surgery

    With an US-guided parasagittal oblique approach, the interlaminar space at the union between laminas and spinous processes at the predefined insertion level will be identified. A skin wheal will be raised with 3 mL of lidocaine 1%. Afterward, an 18-gauge Tuohy epidural block needle will be advanced under direct US vision until the tip is insinuated between the laminas and anchored to the flavum ligament. Then the needle will be attached to a low resistance syringe prefilled with saline solution and advanced until LOR to injection is confirmed. Then a 20-Gauge epidural catheter will be inserted 3-5 cm beyond the needle tip inside the epidural space and the needle removed.

Study groups in NCT05165498
Study groupRoleWhat they receive
Patients undergoing elective thoracic surgery, abdominal surgery, or having rib fracturesPatients undergoing elective thoracic surgery, abdominal surgery, or having rib fractures who will have placed a thoracic epidural catheter to manage their perioperative analgesia.
Receives: Procedure: Real-time ultrasound guidance for thoracic epidural catheter placement.

What is being measured

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

  1. Percentage of successful epidural blocks after US-guided insertion of epidural catheters

    After fifteen minutes of local anesthetic administration (4- mL dose of lidocaine 2% with epinephrine 5 μg/mL ), an investigator will apply ice to the T1 to L4 dermatomes bilaterally. The criterion standard for success will be the presence of an epidural block, defined as a block to ice in at least 2 dermatomes bilaterally. If operators could not advance the catheter past the needle tip after 2 attempts despite a 180-degree rotation of the bevel between the first and second attempts, epidural blocks will be considered failures.

    Measured: 15 minutes after the local anesthetic injection through the epidural catheter

Secondary outcomes (7)

  1. Number of blocked dermatomes

    Number of blocked dermatomes after injection of local anesthetics through the epidural catheter.

    Measured: 15 minutes after the local anesthetic injection through the epidural catheter

  2. Localization of blocked dermatomes

    Localization of blocked dermatomes after injection of local anesthetics through the epidural catheter.

    Measured: 15 minutes after the local anesthetic injection through the epidural catheter

  3. Image time

    Needed time (minutes and seconds) to obtain an adequate image of the interlaminar space

    Measured: Up to 30 minutes after skin disinfection

  4. Needle time

    Needed time (minutes and seconds) to insert the Tuohy needle tip in the interlaminar space and confirm a loss of resistance

    Measured: Up to 30 minutes after skin disinfection

  5. Catheter installation time

    Elapsed time (minutes and seconds) from loss of resistance acquisition until the catheter is secured

    Measured: Up to 30 minutes after skin disinfection

  6. Block performance time

    Time (minutes and seconds) between skin disinfection and once the catheter is secured in place.

    Measured: Up to 30 minutes after skin disinfection

  7. Epidural block-related complications

    Incidence of adverse events related to epidural block or local anesthetic injection (i.e. paresthesia, accidental dural puncture, intravascular or subarachnoid position of catheters, intravascular, subarachnoid or subdural injection, local anesthetic systemic toxicity)

    Measured: Up to 30 minutes after skin disinfection

Timeline

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

  1. First posted21 Dec 2021
  2. Study startJul 2027 (estimated)
  3. Primary completionDec 2028 (estimated)
  4. Study completionDec 2028 (estimated)

Why it stopped: COVID pandemic

Resources

More details

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

Study design
Study type
Observational
Observational model
Case only
Time perspective
Prospective
Enrolment
0 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT05165498
Sponsor's protocol ID
OAIC 1037/19
Status last verified
May 2026
First submitted
7 Dec 2021
Last updated
19 May 2026
Results posted
No
Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No

Publications

  • Tran DQ, Van Zundert TC, Aliste J, Engsusophon P, Finlayson RJ. Primary Failure of Thoracic Epidural Analgesia in Training Centers: The Invisible Elephant? Reg Anesth Pain Med. 2016 May-Jun;41(3):309-13. doi: 10.1097/AAP.0000000000000394.

    PubMed 27035462

  • Tran DQ, Gonzalez AP, Bernucci F, Finlayson RJ. Confirmation of loss-of-resistance for epidural analgesia. Reg Anesth Pain Med. 2015 Mar-Apr;40(2):166-73. doi: 10.1097/AAP.0000000000000217. No abstract available.

    PubMed 25642911

  • Leurcharusmee P, Arnuntasupakul V, Chora De La Garza D, Vijitpavan A, Ah-Kye S, Saelao A, Tiyaprasertkul W, Finlayson RJ, Tran DQ. Reliability of Waveform Analysis as an Adjunct to Loss of Resistance for Thoracic Epidural Blocks. Reg Anesth Pain Med. 2015 Nov-Dec;40(6):694-7. doi: 10.1097/AAP.0000000000000313.

    PubMed 26469364

  • Arnuntasupakul V, Van Zundert TC, Vijitpavan A, Aliste J, Engsusophon P, Leurcharusmee P, Ah-Kye S, Finlayson RJ, Tran DQ. A Randomized Comparison Between Conventional and Waveform-Confirmed Loss of Resistance for Thoracic Epidural Blocks. Reg Anesth Pain Med. 2016 May-Jun;41(3):368-73. doi: 10.1097/AAP.0000000000000369.

    PubMed 26894628

  • Elgueta MF, Duong S, Finlayson RJ, Tran DQ. Ultrasonography for neuraxial blocks: a review of the evidence. Minerva Anestesiol. 2017 May;83(5):512-523. doi: 10.23736/S0375-9393.16.11650-5. Epub 2016 Nov 9.

    PubMed 27827521

  • Pak DJ, Gulati A. Real-Time Ultrasound-Assisted Thoracic Epidural Placement: A Feasibility Study of a Novel Technique. Reg Anesth Pain Med. 2018 Aug;43(6):613-615. doi: 10.1097/AAP.0000000000000761.

    PubMed 29553999

  • Yeager MP, Bae EE, Parra MC, Barr PA, Bonham AK, Sites BD. Fluoroscopy-assisted epidural catheter placement: an exploratory analysis of 303 pre-operative epidurograms. Acta Anaesthesiol Scand. 2016 Apr;60(4):513-9. doi: 10.1111/aas.12649. Epub 2015 Oct 28.

    PubMed 26508378

Questions about this trial

What is this clinical trial studying?

An observational study of Analgesia and Thoracic Tumors, run by University of Chile at 1 site in Chile.

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 3 inclusion and 5 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: withdrawn, as of the sponsor's last update on 19 May 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 Chile. 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 was withdrawn before enrolling participants, so there are no results.

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?

Percentage of successful epidural blocks after US-guided insertion of epidural catheters (time frame: 15 minutes after the local anesthetic injection through the epidural catheter). 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 NCT05165498, which also lists 7 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 19 May 2026.

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