Determination of the Optimal Inspiratory Pressure to Decrease Incidence of Gastric Insufflation With Adequate Ventilation During Facemask Ventilation in Morbidly Obese Patients

NCT07480031 | Not Yet Recruiting DMC

• 1 other identifier: 3.7.2025
• Study Type: interventional
• Target: 144
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this randomized clinical trial is to optimize the inspiratory pressure during facemask ventilation (FMV) in morbidly obese patients (BMI ≥40 kg/m²), to ensure adequate ventilation while minimizing the risk of gastric insufflation by real-time ultrasound guidance

Conditions

Gastric Insufflation

Outcome Measures

Primary Outcomes (1)

• Incidence of Gastric insufflation (ultrasound-confirmed) during FMV

  At 30 seconds, 60 seconds, and 90 seconds after induction

Secondary Outcomes (8)

• Tidal volume (mL/kg ideal body weight) and peak inspiratory pressure

  at 30, 60, and 90 seconds of facemask ventilation (FMV)

• Oxygen saturation (SpO₂)

  At baseline and 30 seconds, 60 seconds, and 90 seconds during FMV

• End tidal CO2

  At baseline and 30 seconds, 60 seconds, and 90 seconds during FMV

• Antral cross-sectional area

  at baseline (15 minutes before induction) and 30, 60, 90 seconds during FMV.

• Heart rate

  At baseline, 30, 60, 90 seconds during facemask ventilation and one minute after endotracheal tube placement

Study Arms (4)

group A

EXPERIMENTAL

This arm will be subjected to inspiratory pressure 10 cmH₂O

Device: "Ultrasound-Guided Optimization of Inspiratory Pressure During Facemask Ventilation"

group B

EXPERIMENTAL

This arm will be subjected to inspiratory pressure 15 cmH₂O

Device: "Ultrasound-Guided Optimization of Inspiratory Pressure During Facemask Ventilation"

group C

EXPERIMENTAL

This arm will be subjected to inspiratory pressure 20 cmH₂O

Device: "Ultrasound-Guided Optimization of Inspiratory Pressure During Facemask Ventilation"

group D

EXPERIMENTAL

This arm will be subjected to inspiratory pressure 25 cmH₂O

Device: "Ultrasound-Guided Optimization of Inspiratory Pressure During Facemask Ventilation"

Interventions

"Ultrasound-Guided Optimization of Inspiratory Pressure During Facemask Ventilation" DEVICE

Description: Group A will be subjected to an inspiratory pressure of 10 cmH₂O. A curvilinear ultrasound probe will be placed in the epigastric region to visualize the antrum. Baseline gastric ultrasound will be performed to confirm an empty stomach. During FMV, ultrasound images will be obtained at 30, 60, and 90 seconds. Gastric insufflation will be detected by the change in gastric cross-sectional area (ΔCSA).

group A

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adult patients (18-65 years old) scheduled for elective surgery under general anesthesia requiring facemask ventilation.
• Morbid obesity (BMI ≥40 kg/m²).
• American Society of Anesthesiologists (ASA) physical status II-III.
• Normal upper gastrointestinal anatomy (no history of gastric surgery, esophageal strictures, or hiatus hernia).
• Fasted for at least 6 hours for solids and 2 hours for fluids (standard preoperative fasting guidelines).

You may not qualify if:

• Emergency surgery (due to inability to ensure proper fasting or preoperative assessment).
• Known or suspected difficult airway (Mallampati class IV, limited neck mobility, or history of difficult intubation).
• Gastroesophageal reflux disease (GERD) or high aspiration risk (e.g., pregnancy, symptomatic hiatal hernia).
• Contraindications to facemask ventilation (facial trauma, beard/mask seal interference).
• Severe cardiopulmonary disease (e.g., severe COPD, pulmonary hypertension, or unstable angina).
• Neuromuscular disorders affecting respiratory function.
• Refusal to participate or inability to provide informed consent.

Sponsors & Collaborators

• Benha University: lead

Study Sites (1)

Benha University Hospitals

Banhā, Egypt

Location

Central Study Contacts

mohamed a mustafa, MSC

CONTACT

+201022708985; mhmdabdelrazik248@gmail.com

alaa b mohamed, MBBCH

CONTACT

+201019680699; alabam7m@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: assistant lecturer

Model Details: •"Face mask ventilation with isoflurane for 90 seconds assisted by oropharyngeal or nasopharyngeal airway before endotracheal intubation. The inspiratory pressure will be adjusted according to the 4 groups at (10-15-20-25 cmH₂O) and set on the anesthesia ventilator (PEEP = 5 cmH₂O). Ventilation will be pressure-controlled with FiO₂ 100%, RR = 14 breaths/min, I:E = 1:2. The study inspiratory pressure refers to the set inspiratory pressure above PEEP (i.e., set PIP). 1. A curvilinear ultrasound probe (2-5 MHz) will be placed in the epigastric region to visualize the antrum. 2. Baseline gastric ultrasound will be performed to confirm an empty stomach (cross-sectional area of the antrum \<3.4 cm²). 3. During FMV, ultrasound images will be obtained at 30 s, 60 s, and 90 s. Gastric insufflation is defined as any of the following: Appearance of air artifacts ("comet tail" or "ring-down" artifacts). Increase in antral cross-sectional area ≥3.4 cm². ΔCSA (cross-sectional area) \>30%."

Study Record Dates

• First Submitted: March 11, 2026
• First Posted: March 18, 2026
• Study Start: April 1, 2026
• Primary Completion (Estimated): April 1, 2027
• Study Completion (Estimated): April 15, 2027
• Last Updated: March 18, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will not share

Locations

EG (1)