High-Flow Nasal Oxygen for Preoxygenation in Emergency Surgery Patients With Full Stomachs

Summary

Patients with full stomachs face a high risk of regurgitation and aspiration under general anesthesia. To minimize the time between the loss of airway protective reflexes and successful tracheal intubation, rapid sequence induction intubation is commonly used. However, these patients are particularly vulnerable to hypoxemia during anesthesia induction, especially in emergency cases. Pre-oxygenation before induction is crucial for ensuring patient safety during apnea.

High-flow nasal oxygen (HFNO) therapy, which consists of an air/oxygen blender, an active humidifier, and a single heated circuit, has recently gained widespread use in intensive care units (ICUs) for managing hypoxemic respiratory failure. HFNC can deliver a constant fraction of inspired oxygen (FiO₂) from 0.21 to 1.0 at high flow rates (up to 60 L/min or higher). Its advantages include generating continuous positive airway pressure, reducing anatomical dead space, improving ventilation-perfusion matching, enhancing mucociliary clearance, and decreasing the work of breathing.

Given these benefits, HFNO has the potential to improve pre-oxygenation before and during anesthesia induction in emergency surgery patients with full stomachs.

Conditions

• High-flow Nasal Cannula
• Oxygenation
• General Anesthesia
• Induction Anesthesia
• Emergency Surgery Patients
• Full Stomach

Interventions

DEVICE

High-flow nasal cannula therapy application

Patients will undergo HFNC preoxygenation for 3 minutes with a flow rate of 60 L/min of heated and humidified pure oxygen (100% FiO₂, 37°C - Optiflow; Fisher \& Paykel Healthcare, Auckland, New Zealand). To minimize air contamination, large or medium nasal cannulae will be selected based on the patient's nostril size

DEVICE

Traditional facemask

Patients will undergo preoxygenation for 3 minutes using a face mask (sized appropriately to fit the patient and ensure an airtight seal) connected to an Aisys CS2 ventilation system (General Electric, GE Healthcare, Oy, Finland). In this group, the ventilation system will be set with a fresh gas flow of 10 L/min, FiO₂ = 100%, without inspiratory support or expiratory positive pressure. The face mask (Economy, Intersurgical, Fontenay-sous-Bois, France) will be removed after induction to enable intubation.

Sponsors & Collaborators

• Hanoi Medical University

  collaborator OTHER

• Phu Tho General Hospital

  collaborator UNKNOWN

• Nguyen Dang Thu

  lead OTHER

Principal Investigators

• Lam Nguyen Duc, Assoc.Prof, PhD, MD · Hanoi Medical University

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2023-07-19

Primary Completion

2026-12-15

Completion

2026-12-31

Countries

• Vietnam

Study Locations