Ultrasound-guided Interscalene Block Versus Infraspinatus-Teres Minor Plane Block in Shoulder Arthroscopy

Not Applicable

Not yet recruiting

• Conditions: Pain; Pain Management; Pain Management in Postoperative Care

• Registration Number: NCT07016386
• Lead Sponsor: Misr University for Science and Technology

Brief Summary

This study aims to compare the efficacy and safety of ultrasound-guided Interscalene block (ISB) versus Infraspinatus-Teres minor (ITM) interfacial plane block in shoulder arthroscopic surgery.

A prospective, randomized clinical trial will be conducted with 46 patients. Approval was obtained from the Medical Ethics Committee (2022/0126), and written informed consent will be collected from all participants. Patients aged 20-70, ASA I-II, scheduled for arthroscopic shoulder surgery will be divided before the induction of general anesthesia (GA) into two groups:

Group A: will receive the ultrasound guided ISB technique with a 15ml solution of 7.5ml lidocaine 2% and 7.5ml bupivacaine 0.5% be injected between the anterior and middle scalene muscles.

Group B: will receive the ultrasound guided ITM block with the same anesthetic solution be injected between the infraspinatus and teres minor muscles.

Researchers will examine the following outcomes;

1. Primary outcome measure: Efficacy of analgesia by Pain score; will be measured by Numerical Rating Scale (NRS) score (0=no pain,1-3=mild,4-6=moderate,7-9=sever,10=most sever) at postoperative 12 hour.

2. Secondary outcome measures:

1. Duration of analgesia, starting from recovery from general anesthesia (GA) to 1st time giving the patient rescue analgesia ( measured by NRS pain score at 0, 6 ,12, 18 and 24 postoperative hours)

2. Risk of complications from techniques

3. Patient satisfaction after surgery.

4. Rescue analgesic consumption

5. Hemodynamics monitoring; measurements of heart rate and mean arterial blood pressure before induction of anesthesia and every 15 minutes during surgery till end of surgery

Detailed Description

I. Study design:

Randomized comparative study.

II. Study setting and location:

The study will be conducted at the operative room of Souad Kafafi University Hospital (SKUH), Misr University of science and Technology (MUST).

III. Study population:

Patients aged from 20 to 60 years old scheduled for shoulder surgery will be randomized in a 1:1 ratio after induction of general anesthesia (GA) to either: Group A: Received the ultrasound guided ISB technique with a 15ml solution of 7.5ml lidocaine 2% and 7.5ml bupivacaine 0.5% injected between the anterior and middle scalene muscles.

Group B: Received the ultrasound guided ITM block with the same anesthetic solution injected between the infraspinatus and teres minor muscles.

IV. Study procedures:

1. Randomization Patients will be randomly allocated by a computer-generated table into one of the study groups; the randomization sequence will be concealed in sealed opaque envelopes.

2. Study protocol

* All Patients will have a pre-operative assessment visit, which will include; history taking, complete physical examination and review of all the results of the routine investigations (CBC, Coagulation profile, renal functions, liver functions).

* On Arrival to the preparation room, they will receive the following premedication via intravenous (IV) route: Midazolam 0.03 mg/kg, Ondansetron 4 mg and Omeprazole 40 mg iv infusion.

* Upon Arrival to the operating room, standard monitoring will be applied which include: Pulse Oximeter, Noninvasive Blood Pressure and Six-lead electrocardiogram (ECG).

* General anesthesia will be induced using: Propofol 1-2mg/kg, Fentanyl1-2 μg/kg, Morphine 0.1mg/kg and Atracurium 0.5 mg/kg.

* After endotracheal intubation, side way capnography will be applied to measure end tidal CO2 pressure in the expired air.

* General anesthesia will be maintained using Sevoflurane 1-2 MAC (Mean Alveolar Concentrations) in O2/ Air 50% / 50%, Paracetamol 1gm iv infusion, ketorolac 30 mg iv and incremental doses of Atracurium 0.1mg/kg/30 minutes.

The patients will be randomly allocated into two groups:

Group A:

Ultrasound-guided Interscalene block (ISB) technique.

Group B:

Ultrasound-guided Infraspinatus-teres minor (ITM) interfacial plane block technique

V. Study outcomes:

1. Primary outcome measure:

• Efficacy of analgesia by Pain score; will be measured by Numerical Rating Scale (NRS) score (0-10; 0=no pain,1-3=mild,4-6=moderate,7-9=sever,10=most sever) at postoperative12 hours.

2. Secondary outcome measures:

1. Duration of analgesia, starting from recovery from general anesthesia (GA) to 1st time giving the patient rescue analgesia ( measured by NRS pain score at 0, 6 ,12, 18 and 24 postoperative hours).

2. Risk of complications from techniques.

3. Patient satisfaction after surgery

4. Total intraoperative analgesia dose (fentanyl consumption) and total postoperative analgesia dose (morphine consumption).

5. Hemodynamics monitoring; measurements of heart rate and mean arterial blood pressure before induction of anesthesia and every 15 minutes during surgery till end of surgery

VII. Statistical analysis:

1. Sample size:

Sample size calculation was based on pain score after Interscalene block (ISB) in shoulder surgery versus other methods retrieved from previous research (Singelyn et al., 2004) (15). Using G power program version 3.1.9.4 to calculate sample size based on effect size of 0.897 (35 ± 25) versus (13±24), using 2-tailed test, α error =0.05 and power = 80.0%, the total calculated sample size will be 21 in each group at least and by adding 10% to compensate for possible drop out then total sample size per group is 23 cases at least.

2. Statistical analysis:

Data will be analyzed using SPSS (statistical package for social sciences) version 22. Quantitative data will be tested for normality by Kolmogrov-Smironv test then described as mean and standard deviation for normally distributed data, and median and range for non-normally distributed, Qualitative data will be presented as number and percent. The appropriate statistical test will be applied according to data type with the following suggested tests: Student t test and Mann Whitney U test for continuous variables, Chi-Square test for categorical variable.

Study Timeline

• Study First Submitted: 2025-05-24
• Status Verified: 2025-06
• Study First Submitted QC: 2025-06-03
• Study First Posted: 2025-06-11
• Last Update Submitted: 2025-06-11
• Study Start: 2025-06-15
• Last Update Posted: 2025-06-15
• Primary Completion: 2026-01-20
• Study Completion: 2026-01-31

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 46

Inclusion Criteria

• Patients aged 20 to 60,
• ASA classification I or II,
• scheduled for arthroscopic shoulder surgery,
• will be randomized 1:1 into two groups before the induction of general anesthesia (GA)

Exclusion Criteria

• Patients who refuse participation.
• Have allergies to local anesthetics.
• Phrenic nerve dysfunction.
• Chronic opioid use.
• ASA III or higher classification.
• Coagulopathy.
• Severe chronic obstructive pulmonary disease.
• Local infection at the injection site

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Efficacy of analgesia	at 12 hours postoperatively	Will be measured by pain score at 12 hours postoperatively using the Numerical Rating Scale (NRS) (0-10; with 0 means no pain and 10 means most intolerable pain)

Secondary Outcome Measures

Name	Time	Method
Duration of analgesia	Starting from recovery from general anesthesia (GA) to 1st time giving the patient rescue analgesia,	duration of analgesia measured by Pain score at 0, 6, 12, 18, and 24 hours postoperatively using the Numerical Rating Scale (NRS) 0-10 with 0 means no pain and 10 means most intolerable pain.
Complications of the techniques	From time of injection to the end of first 24 hours postoperative	Local anesthetics toxicity, pneumothorax, phrenic nerve palsy, hematoma formation
Total postoperative morphine consumption (mg)	From recovery from general anesthesia to end of 24hours postoperatively	Time to 1st request of rescue analgesia and total dose of postoperative morphine consumption in the studied groups for 24 hours (mg)
Hemodynamics; mean arterial blood pressure (mmHg)	Before induction of anesthesia and every 15 minutes during surgery till end of surgery	Measurement of mean arterial blood pressure (mmHg)
Hemodynamics (heart rate)	before induction of anesthesia and every 15 minutes during surgery till end of surgery	measurements of heart rate (beat per minute)
Total intraoperative analgesic consumption (fentanyl).	During surgery; from induction of anesthesia to end of surgery.	Need and consumption of fentanyl intraoperatively (ug),
Patient satisfaction	for the first postoperative 24 hours	very unsatisfied, unsatisfied, neutral, satisfied, very satisfied

Trial Locations

Locations (1)

Souad Kafafi University Hospital (SKUH), Faculty of medicine, Misr University for Science and Technology (MUST); 🇪🇬 Giza, Egypt