Gastric Insufflation During Facemask Ventilation at Different Levels of End-expiratory Pressure in Obese Patients

NCT05979129 | Completed

• 1 other identifier: MD-65-2022
• Study Type: interventional
• Target: 162
• Locations: 1 country
• Sites: 1

Brief Summary

Gastric insufflation occurs when the inspiratory pressure exceeds the lower esophageal sphincter pressure. Thus, it is desirable to avoid excessive positive pressure during mask ventilation after induction of anesthesia and keeping the inspiratory pressure \<15-20 cmH2O.In patients with obesity the lower compliance of the respiratory system usually requires higher inspiratory pressures to maintain adequate ventilation making these patients more prone to gastric insufflation. This high risk of gastric insufflation can be aggravated by the use of positive end-expiratory pressure (PEEP) which is recommended to avoid lung atelectasis. The application of PEEP during mask ventilation increases the risk of gastric insufflation as it reduces the pressure threshold at which gastric insufflation occur The optimum ventilatory strategy during mask ventilation should achieve the balance between adequate lung ventilation and avoiding gastric insufflation. In obese patients, it is not clear whether the use of PEEP during mask ventilation would increase the risk of gastric insufflation or not. We hypothesize that using zero end-expiratory pressure (ZEEP) or low PEEP during mask ventilation would reduce the risk of gastric insufflation in comparison to high PEEP.

Conditions

Gastric Insufflation; Face-mask Ventilation; Obese; Positive End Expiratory Pressure

Outcome Measures

Primary Outcomes (1)

• Change in gastric cross sectional area more than 30%

  number of patients with increase in percentage of change in gastric cross sectional area by more than 30%

  1 minute before preoxygenation and 1 minute after intubation

Secondary Outcomes (6)

• gastric cross sectional area

  1 minute before preoxygenation and 1 minute after intubation

• percentage of change in gastric cross sectional area

  1 minute before preoxygenation and 1 minute after intubation

• tidal volume

  30 seconds until 120 seconds after induction of anesthesia

• end-tidal CO2

  30 seconds until 120 seconds after induction of anesthesia

• Peak airway pressure

  30 seconds until 120 seconds after induction of anesthesia

Study Arms (3)

ZEEP group

ACTIVE COMPARATOR

Other: zero PEEP

Low PEEP

ACTIVE COMPARATOR

Other: low PEEP

High PEEP

ACTIVE COMPARATOR

Other: high PEEP

Interventions

zero PEEP OTHER

zero end-expiratory pressure during face mask ventilation

ZEEP group

low PEEP OTHER

4 cmH2O PEEP during mask ventilation

Low PEEP

high PEEP OTHER

8 cmH2O PEEP during mask ventilation

High PEEP

Eligibility Criteria

• Age: 18 Years - 60 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• adult patients,
• with American Society of Anesthesiologists physical status II,
• body mass index \>35 kg/m2,
• scheduled for elective surgery under general anesthesia.

You may not qualify if:

• Patients at increased risk of difficult mask ventilation: Mallampati classification \>2, presence of beard, limited neck extension, limited jaw protrusion, patients with history of obstructive sleep apnea or STOP-Bang score\>2
• Patients at risk of aspiration or history of esophageal reflux.
• Patients with craniofacial anomalies, and pregnant patients

Sponsors & Collaborators

• Kasr El Aini Hospital: lead

Study Sites (1)

Kasr Alaini Hospital

Cairo, 11562, Egypt

Location

Related Publications (1)

• Mostafa M, Hasanin A, Zakaria MM, Kandel H, Hamimy W, Abougabal A, Elshal MM. Comparing the effect of three levels of end-expiratory pressure during facemask ventilation on gastric insufflation in patients with obesity: a randomized controlled trial. J Anesth. 2025 Dec;39(6):887-895. doi: 10.1007/s00540-025-03531-9. Epub 2025 Jun 30.

  PMID: 40586940 DERIVED

MeSH Terms

Conditions

Obesity

Condition Hierarchy (Ancestors)

Overweight; Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Design

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

Study Record Dates

• First Submitted: July 30, 2023
• First Posted: August 7, 2023
• Study Start: August 6, 2023
• Primary Completion: April 28, 2024
• Study Completion: April 28, 2024
• Last Updated: August 5, 2024

Record last verified: 2024-08

Data Sharing

• IPD Sharing: Will not share

Locations

EG (1)