US-guided Airway Nerve Block vs. Topical Lidocaine in Video Laryngoscopy for Difficult Bariatric Intubation.

NCT ID: NCT07069686

Last Updated: 2025-07-17

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 80 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-02-20
• Study Completion Date: 2025-05-28

Brief Summary

The investigators will test the effects of ultrasound guided airway nerve block vs lidocaine topical anesthesia and it's direct effect in decreasing incidence of gag and cough reflex in suspected difficult intubation patients using video assisted laryngoscopey for those Undergoing bariatric surgery

Detailed Description

A.Preoperative settings:

A thorough preoperative evaluation including a complete airway evaluation (mouth opening, mallampati grading, body weight, thyromental distance, and evaluation of dentition) will be performed. Standard fasting guidelines and anti-aspiration prophylaxis with tablet ranitidine 150 mg will be prescribed.

The patients will be explained about the awake C-MAC intubation during preoperative assessment.Injection of atropine 0.4 mg will be given half an hour before shifting the patient to the operating room (OR).

B.Intraoperative and postoperative settings:

Injection of atropine 0.4 mg will be given half an hour before shifting the patient to the operating room (OR). Inside the OR, standard monitoring, including electrocardiography (ECG), noninvasive blood pressure (BP), and pulse oximetry (SpO2) will be applied in all patients. An intravenous (IV) line will be secured and ringer lactate will be started. After recording the baseline heart rate (HR), BP and SpO2, Injection of Dexametomidate 0.7 mcg/kg/hr IV infusion and injection ketamine 0.5-2 mg/kg slow IV single dose until endotracheal tube secured.

For each group, local anesthetics will be given in first group (LA)guided by ultrasound and second group (T) with topical method until Adequate effect of local anesthesia confirmed by hoarseness of voice in Group LA patients and numbness of tongue in Group T patients. While giving supplemental oxygen through nasal prongs, C-MAC intubation will be performed. After the airway is secured, general anesthesia will be administered with propofol 2 mg/kg, and rocuronium 0.6 mg/kg.

Postoperatively, patient comfort will be assessed for sore throat, dysphagia, voice change, or any lip, gum, tongue, dental injuries, complete amnesia, partial recall, and unpleasant memories during awake C-MAC intubation.

Conditions

Gag Reflex

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: OTHER
• Blinding Strategy: SINGLE

Study Groups

Group LA

patients will be intubated using the video-assisted laryngoscope after taking airway nerves block guided by ultrasound device

Group Type: ACTIVE_COMPARATOR

Ultrasound guided airway nerve block for Endotracheal intubation

Intervention Type: PROCEDURE

Glossopharyngeal nerve block: 1.5 mL 2% lidocaine, ultrasound probe on lateral neck below mandible, landmark = hyoid bone, tilt cephalad to target pharyngeal wall near tonsil; right side needle inserted out-of-plane from superior probe edge to avoid artery. Bilateral superior laryngeal nerve blocks: out-of-plane at lateral thyroid cartilage, orient probe medially, inject 1 mL 2% lidocaine into thyrohyoid membrane between hyoid and thyroid cartilage using 25-G 25 mm needle. Bilateral recurrent laryngeal nerve blocks: translaryngeal out-of-plane, locate cricothyroid membrane below thyroid cartilage, insert 25-G 25 mm needle 1.5 cm, confirm air backflow, inject 2 mL 2% lidocaine.

Group T

patients will be intubated using the video-assisted laryngoscope after topical lidocaine 10% spraying as-you-go to oro-pharyngeo-laryngeal cavity without exceeding the toxic dose.

Group Type: ACTIVE_COMPARATOR

lidocaine topical anesthesia for Endotracheal intubation

Intervention Type: PROCEDURE

will receive topical lidocaine 10% spray directly on the tongue and oropharynx without exceeding toxic doses.

Interventions

Ultrasound guided airway nerve block for Endotracheal intubation

Glossopharyngeal nerve block: 1.5 mL 2% lidocaine, ultrasound probe on lateral neck below mandible, landmark = hyoid bone, tilt cephalad to target pharyngeal wall near tonsil; right side needle inserted out-of-plane from superior probe edge to avoid artery. Bilateral superior laryngeal nerve blocks: out-of-plane at lateral thyroid cartilage, orient probe medially, inject 1 mL 2% lidocaine into thyrohyoid membrane between hyoid and thyroid cartilage using 25-G 25 mm needle. Bilateral recurrent laryngeal nerve blocks: translaryngeal out-of-plane, locate cricothyroid membrane below thyroid cartilage, insert 25-G 25 mm needle 1.5 cm, confirm air backflow, inject 2 mL 2% lidocaine.

Intervention Type: PROCEDURE

lidocaine topical anesthesia for Endotracheal intubation

will receive topical lidocaine 10% spray directly on the tongue and oropharynx without exceeding toxic doses.

Intervention Type: PROCEDURE

Eligibility Criteria

Inclusion Criteria

1. Age: 21-65 years old

2. Obese patients (BMI>35 kg/m2) undergoing bariatric surgery

3. Suspected difficult intubation: e.g:(Mallampati score ≥3 , Thyromental distance <6 cm, Limited neck mobility, History of difficult intubation)

4. ASA I-II

Exclusion Criteria

1. Patients at increased risk for aspiration (e.g., full stomach or gastro-esophageal reflux disease) and pregnancy

2. Patients with expected difficult ventilation

3. Patients who have upper airway pathology or surgery

4. Patients with a mouth opening < 2 cm

5. ASA III-IV

6. Emergency surgery

7. Allergy to local anesthetics

8. Contraindication to nerve blocks e.g.:(Coagulopathy, Infection at site of injection)

9. Patient refusal

10. Neurological or cognitive impairment making the patient uncooperative

11. History of difficult airway complications e.g.: previous intubation failure or need for surgical airway

12. Cervical spine instability or fractures

• Minimum Eligible Age: 21 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Ain Shams University

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

David B Nabih, M.B.B.CH

Role: PRINCIPAL_INVESTIGATOR

Anesthesia resident Ain Shams University

Locations

Ain Shams University

Cairo, Egypt, Egypt

Countries

Egypt

Other Identifiers

FMASU MS 120/2025

Identifier Type: -

Identifier Source: org_study_id