Diaphragm IssuesNCT07338630
Comparison of the Interscalene Block Alone Versus Combined With Superior Truncus Block During Shoulder Surgery in Diaphragmatic Function
A study testing Regional anesthesia in shoulder surgery in people with Diaphragm Issues, run by Sohag University.
Trial summary
Primarily, This study aims to compare between interscalene block alone versus combined with superior truncus block in producing diaphragmatic paralysis and Secondarily aims to evaluate 1. Effect on the pulmonary function. 2. Duration of the sensory and motor block. 3. Postoperative analgesic consumption. 4. Read more about this study
- Who is it for?
- Ages 20 to 65 yearsHealthy volunteers can take part
- Conditions the study is for
- Diaphragm Issues
- What is being tested?
- Regional anesthesia in shoulder surgery
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 60 participants
- Where
- No sites listed yet
- Study dates
- 1 Apr 2026to 1 Jun 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
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 20 to 65 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- ASA (American Society of Anesthesiologists) I, II physical status.
- Aged between 20 and 65 years.
- Male or female.
- Body Mass index (BMI): 18-30 kg/m3.
- Scheduled for shoulder surgery.
Who cannot join
- Allergy to local anesthetics.
- Infection at the injection site.
- Coagulation disorders.
- Respiratory diseases ( Acute or Chronic) or Chest trauma.
- Multiple traumatized patients.
- Phrenic nerve injury
Show all 9Show fewer
- Heart failure, Cardiomyopathy.
- Severe organ dysfunction
- Patient refusal
Trial locations and contacts
No sites are listed yet. Contact the study team or a site near you to ask about taking part.
El hadad Ali Mosa Professor of Anesthesia contact
About this study
Official title: Phrenic Nerve Sparing of the Interscalene Block Alone Versus Combined With Superior Truncus Block During Shoulder Surgery , Prospective Comparative Randomized Study
Primarily, This study aims to compare between interscalene block alone versus combined with superior truncus block in producing diaphragmatic paralysis and Secondarily aims to evaluate
- Effect on the pulmonary function.
- Duration of the sensory and motor block.
- Postoperative analgesic consumption.
- Any complications or side effects during shoulder surgery.
Read the detailed description
Regional anesthesia is central to modern shoulder surgery because it provides excellent perioperative analgesia, reduces opioid consumption, and facilitates early rehabilitation. The interscalene brachial plexus block (ISB) has long been considered the gold-standard single-shot regional technique for shoulder procedures due to its reliable analgesia and surgical anesthesia. However, ISB commonly causes ipsilateral hemidiaphragmatic paresis (HDP) from unintended phrenic nerve blockade, which can produce clinically important declines in pulmonary function and may be poorly tolerated in patients with limited respiratory reserve.
To minimize phrenic involvement while preserving analgesic effectiveness, more selective approaches have been proposed. The superior trunk block (STB) - performed at the level where C5-C6 fibers form the superior trunk - aims to anesthetize the shoulder innervation more distally and thus reduce spread to the phrenic nerve. A landmark randomized trial and subsequent studies reported that STB provides analgesia comparable to ISB while greatly lowering the incidence of HDP (for example, ISB 71% vs STB 5% in one trial). Systematic reviews and meta-analyses since then have reinforced STB as an effective phrenic-sparing alternative for many shoulder procedures.
Despite encouraging data for STB, the literature is not entirely uniform. Some randomized trials and observational reports have found either reduced anesthetic quality with STB or smaller-than-expected reductions in phrenic involvement, particularly when block technique, local anesthetic volume, or patient anatomy differ. Moreover, combining blocks (for example, ISB with selective superior-trunk targeting or other modifications) has been proposed as a strategy to balance surgical anesthesia and respiratory safety, but comparative prospective data examining the effect of ISB alone versus ISB combined with STB on diaphragmatic function are limited. This uncertainty is important because even partial diaphragmatic paresis can degrade postoperative pulmonary mechanics and increase complications in vulnerable patients.
- Conditions
- Diaphragm Issues
- Being tested
- Regional anesthesia in shoulder surgery
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Regional anesthesia in shoulder surgeryOther
Comparison of the interscalene block alone versus combined with superior truncus block during shoulder surgery in diaphragmatic function
| Study group | Role | What they receive |
|---|---|---|
| Interscalene block alone | Active comparator | Interscalene block alone, we will inject 20 mL of 0.5 % bupivacaine plus 10 mL of 0.9 % normal saline around brachial plexus in the interscalene site under ultrasonograhy. Receives: Other: Regional anesthesia in shoulder surgery |
| Interscalene block plus Superior truncus block | Active comparator | 1. We will inject 7 mL of 0.5 % bupivacaine plus 3 mL of 0.9 % normal saline ( Total amount 10 ml) around brachial plexus in the interscalene site under ultrasonograhy.
2. Also we will inject 13 mL of 0.5 % bupivacaine plus 7 mL of 0.9 % normal saline ( Total amount 20 ml) around Superior trunk of brachial plexus under ultrasonagraphy. Receives: Other: Regional anesthesia in shoulder surgery |
What is being measured
The primary outcome is the main question the study is designed to answer.
Comparison between interscalene block alone versus combined with superior truncus block inproducing diaphragmatic paralysis
Assessment of diaphragmatic function by diaphragm excursion (DE) and diaphragm thickening fraction (TF) will be measured both before and 30 minutes post-block. To measure DE, patients will be placed in a supine position, a convex transducer (3.5 ~ 5 MHz) will be used to scan while the right diaphragm through the hepatic window and the left diaphragm through the splenic window, which located near the anterior-axillary line. The craniocaudal movement of the diaphragm will be documented during deep inspiration using M-mode.
- Complete diaphragmatic paralysis was defined as a 75% ~ 100% reduction in DE, including the occurrence of paradoxical movement.
- Partial diaphragmatic paralysis was defined as a 25% ~ 75% reduction in DE.
- No diaphragmatic paralysis was indicated by a DE reduction of less than 25%. To measure TF, patients will be placed in the same position with the head of the bed at 45°degree
Measured: Assessment of diaphragmatic function by diaphragm excursion (DE) and diaphragm thickening fraction (TF) will be measured both before and 30 minutes post-block.
Secondary outcomes (4)
Evaluation of the interscalene block alone versus combined with superior truncus block during shoulder surgery on the pulmonary function
Assessment of pulmonary function by a handheld spirometer to measure forced vital capacity (FVC), forced expiratory volume ( FEV1, FEV2) with patients in an upright-seated position pre-block and 30 minutes post-block as well as 2-hours post-surgery. Spirometry will be performed three times, with the best effort recorded.
Measured: Assessment of pulmonary function by a handheld spirometer to measure forced vital capacity (FVC), forced expiratory volume ( FEV1, FEV2) with patients in an upright-seated position pre-block and 30 minutes post-block as well as 2-hours post-surgery
Duration of the sensory and motor block onset, duration of the interscalene block alone versus combined with superior truncus block during shoulder surgery
Sensory block onset time will be assessed at the time from local anesthetics injection by pinprick test which will be preformed with 22-gauge short beveled needle every minute. Sensory block recovery time will be noted every hour in 1st 6 hours, every 2 hours in 2nd 6 hours till recovery of all pain sensation in all dermatomes performed by pinprick test.
Motor block onset time will be assessed at the time from local anesthetics injection until complete motor block which will be assessed by absence of voluntary movement on asking the patient to elevate his arm every minute. Motor block recovery time will be noted as the time of return of voluntary movement in the arm every hour in 1st 6 hours, every 2 hours in 2nd 6 hours.
Measured: Sensory, motor block onset time every minute. Sensory, Motor block duration every hour in 1st 6 hours , every 2 hours in 2nd 6 hours
Evaluation of postoperative analgesic consumption
Pain will be evaluated Postoperative immediately every hour in 1st 6 hours, every 2 hours in 2nd 6 hours by Visual Analogue Scale ( VAS) by instructing the patient to point to the position on the line to indicate how much pain they are currently feeling(10).
- VAS (zero) indicates no pain.
- VAS ( 1, 2, 3) indicates mild pain.
- VAS ( 4, 5, 6) indicates moderate pain.
- VAS ( 7, 8, 9, 10) : indicates severe pain.
Measured: 12 hours
Evaluation of any complications or side effects during shoulder surgery
Any local or systemic complications or side effects will be recorded every 2 hours post operative for 24 hours such as local anesthetic systemic toxicity (LAST), Horner's syndrome, hypoxia, dyspnea, pneumothorax and post-operative nausea and vomiting (PONV).
Measured: 24 hours
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted14 Jan 2026
- Study start1 Apr 2026 (estimated)
- Primary completion1 Apr 2027 (estimated)
- Study completion1 Jun 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Diaphragm IssuesStudies of the same condition, open and under way.
- More trials run by Sohag UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
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
- Diagnosis
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- The patients will be allocated to two groups : * Group I (30 patients) : Interscalene block alone, we will inject 20 mL of 0.5 % bupivacaine plus 10 mL of 0.9 % normal saline around brachial plexus in the interscalene site under ultrasonograhy. * Group S(30 patients): Interscalene block plus Superior truncus block 1. We will inject 7 mL of 0.5 % bupivacaine plus 3 mL of 0.9 % normal saline ( Total amount 10 ml) around brachial plexus in the interscalene site under ultrasonograhy. 2. Also we will inject 13 mL of 0.5 % bupivacaine plus 7 mL of 0.9 % normal saline ( Total amount 20 ml) around Superior trunk of brachial plexus under ultrasonagraphy.
- Masking
- Triple blind
- Who is masked
- Participant, Investigator, Outcomes assessor
- Enrolment
- 60 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Sohag University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Sherif Salah Ismail, Sohag University
- Investigators
- Sherif Salah Ismail Assistant lecturer of Anesthesia, Principal investigator, Assistant lecturer of Anesthesia and ICU and Pain Management of Sohag University hospitals
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07338630
- Sponsor's protocol ID
- Soh-Med--25-11-5MD
- Status last verified
- Jan 2026
- First submitted
- 8 Dec 2025
- Last updated
- 6 Feb 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 6 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Phrenic Nerve Sparing of the Interscalene Block Alone Versus Combined With Superior Truncus Block During Shoulder Surgery , Prospective Comparative Randomized Study
- ClinicalTrials.gov ID
- NCT07338630
- Acronym / sponsor ID
- Soh-Med--25-11-5MD
- Conditions
- Diaphragm Issues
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 60 participants (estimated)
- Lead sponsor
- Sohag UniversityUniversity, hospital or other
- Study start
- 1 Apr 2026 (estimated)
- Primary completion
- 1 Apr 2027 (estimated)
- Study completion
- 1 Jun 2027 (estimated)
- First posted
- 14 Jan 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Primarily, This study aims to compare between interscalene block alone versus combined with superior truncus block in producing diaphragmatic paralysis and Secondarily aims to evaluate
- Effect on the pulmonary function.
- Duration of the sensory and motor block.
- Postoperative analgesic consumption.
- Any complications or side effects during shoulder surgery.
Detailed description
Regional anesthesia is central to modern shoulder surgery because it provides excellent perioperative analgesia, reduces opioid consumption, and facilitates early rehabilitation. The interscalene brachial plexus block (ISB) has long been considered the gold-standard single-shot regional technique for shoulder procedures due to its reliable analgesia and surgical anesthesia. However, ISB commonly causes ipsilateral hemidiaphragmatic paresis (HDP) from unintended phrenic nerve blockade, which can produce clinically important declines in pulmonary function and may be poorly tolerated in patients with limited respiratory reserve.
To minimize phrenic involvement while preserving analgesic effectiveness, more selective approaches have been proposed. The superior trunk block (STB) - performed at the level where C5-C6 fibers form the superior trunk - aims to anesthetize the shoulder innervation more distally and thus reduce spread to the phrenic nerve. A landmark randomized trial and subsequent studies reported that STB provides analgesia comparable to ISB while greatly lowering the incidence of HDP (for example, ISB 71% vs STB 5% in one trial). Systematic reviews and meta-analyses since then have reinforced STB as an effective phrenic-sparing alternative for many shoulder procedures.
Despite encouraging data for STB, the literature is not entirely uniform. Some randomized trials and observational reports have found either reduced anesthetic quality with STB or smaller-than-expected reductions in phrenic involvement, particularly when block technique, local anesthetic volume, or patient anatomy differ. Moreover, combining blocks (for example, ISB with selective superior-trunk targeting or other modifications) has been proposed as a strategy to balance surgical anesthesia and respiratory safety, but comparative prospective data examining the effect of ISB alone versus ISB combined with STB on diaphragmatic function are limited. This uncertainty is important because even partial diaphragmatic paresis can degrade postoperative pulmonary mechanics and increase complications in vulnerable patients.
Study design
- Primary purpose
- Diagnosis
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind (participant, investigator, outcomes assessor)
- Number of arms
- 2
- Model description
- The patients will be allocated to two groups : * Group I (30 patients) : Interscalene block alone, we will inject 20 mL of 0.5 % bupivacaine plus 10 mL of 0.9 % normal saline around brachial plexus in the interscalene site under ultrasonograhy. * Group S(30 patients): Interscalene block plus Superior truncus block 1. We will inject 7 mL of 0.5 % bupivacaine plus 3 mL of 0.9 % normal saline ( Total amount 10 ml) around brachial plexus in the interscalene site under ultrasonograhy. 2. Also we will inject 13 mL of 0.5 % bupivacaine plus 7 mL of 0.9 % normal saline ( Total amount 20 ml) around Superior trunk of brachial plexus under ultrasonagraphy.
| Arm | Type | Receives |
|---|---|---|
| Interscalene block alone | Active comparator | Other: Regional anesthesia in shoulder surgeryInterscalene block alone, we will inject 20 mL of 0.5 % bupivacaine plus 10 mL of 0.9 % normal saline around brachial plexus in the interscalene site under ultrasonograhy. |
| Interscalene block plus Superior truncus block | Active comparator | Other: Regional anesthesia in shoulder surgery1. We will inject 7 mL of 0.5 % bupivacaine plus 3 mL of 0.9 % normal saline ( Total amount 10 ml) around brachial plexus in the interscalene site under ultrasonograhy. 2. Also we will inject 13 mL of 0.5 % bupivacaine plus 7 mL of 0.9 % normal saline ( Total amount 20 ml) around Superior trunk of brachial plexus under ultrasonagraphy. |
Who may qualify
- Ages
- 20 to 65 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- ASA (American Society of Anesthesiologists) I, II physical status.
- Aged between 20 and 65 years.
- Male or female.
- Body Mass index (BMI): 18-30 kg/m3.
- Scheduled for shoulder surgery.
Key exclusion criteria (9 listed)
- Allergy to local anesthetics.
- Infection at the injection site.
- Coagulation disorders.
- Respiratory diseases ( Acute or Chronic) or Chest trauma.
- Multiple traumatized patients.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Regional anesthesia in shoulder surgeryComparison of the interscalene block alone versus combined with superior truncus block during shoulder surgery in diaphragmatic function | Other | Interscalene block alone, Interscalene block plus Superior truncus block |
Primary outcome
Comparison between interscalene block alone versus combined with superior truncus block inproducing diaphragmatic paralysis
Time frame: Assessment of diaphragmatic function by diaphragm excursion (DE) and diaphragm thickening fraction (TF) will be measured both before and 30 minutes post-block.
Assessment of diaphragmatic function by diaphragm excursion (DE) and diaphragm thickening fraction (TF) will be measured both before and 30 minutes post-block. To measure DE, patients will be placed in a supine position, a convex transducer (3.5 ~ 5 MHz) will be used to scan while the right diaphragm through the hepatic window and the left diaphragm through the splenic window, which located near the anterior-axillary line. The craniocaudal movement of the diaphragm will be documented during deep inspiration using M-mode. * Complete diaphragmatic paralysis was defined as a 75% ~ 100% reduction in DE, including the occurrence of paradoxical movement. * Partial diaphragmatic paralysis was defined as a 25% ~ 75% reduction in DE. * No diaphragmatic paralysis was indicated by a DE reduction of less than 25%. To measure TF, patients will be placed in the same position with the head of the bed at 45°degree
4 secondary outcomes
Evaluation of the interscalene block alone versus combined with superior truncus block during shoulder surgery on the pulmonary function
Time frame: Assessment of pulmonary function by a handheld spirometer to measure forced vital capacity (FVC), forced expiratory volume ( FEV1, FEV2) with patients in an upright-seated position pre-block and 30 minutes post-block as well as 2-hours post-surgery
Duration of the sensory and motor block onset, duration of the interscalene block alone versus combined with superior truncus block during shoulder surgery
Time frame: Sensory, motor block onset time every minute. Sensory, Motor block duration every hour in 1st 6 hours , every 2 hours in 2nd 6 hours
Evaluation of postoperative analgesic consumption
Time frame: 12 hours
Evaluation of any complications or side effects during shoulder surgery
Time frame: 24 hours
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Feb 2026.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
El hadad Ali Mosa Professor of Anesthesia contact
Sherif Salah Ismail Assistant lecturer of Anesthesia principal investigator
Assistant lecturer of Anesthesia and ICU and Pain Management of Sohag University hospitals
Questions about this trial
What is this clinical trial studying?
A study testing Regional anesthesia in shoulder surgery in people with Diaphragm Issues, run by Sohag University.
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 5 inclusion and 9 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: opening soon, as of the sponsor's last update on 6 Feb 2026. Status can change between updates, so confirm with the study contact before making plans.
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?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Sherif Salah Ismail Assistant lecturer of Anesthesia (01007272718, sherifsalah383@gmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Comparison between interscalene block alone versus combined with superior truncus block inproducing diaphragmatic paralysis (time frame: Assessment of diaphragmatic function by diaphragm excursion (DE) and diaphragm thickening fraction (TF) will be measured both before and 30 minutes post-block.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 6 Feb 2026.