Comparison Physiological Effects According to Preoxygenation Method Using EIT (PreoxyEIT)

A Pilot Randomized Trial of Preoxygenation Methods and Their Impacts on Endotracheal Intubation in Acute Respiratory Failure: an Electrical Impedance Tomography Study

Hypoxemia during endotracheal intubation is one of this procedure's most frequent and severe complications, which can lead to cardiac arrest and other adverse outcomes. Although various studies have been conducted to ensure the safety of endotracheal intubation, most of them have focused on the physiological changes during the procedure in surgical settings, where general anesthesia is administered to healthy subjects. However, the physiological characteristics of critically ill patients who require endotracheal intubation in the intensive care unit (ICU) may differ from those of healthy subjects. When comparing the oxygen saturation-dissociation curve of healthy subjects and critically ill patients, the latter show a steeper decline in oxygen saturation (SpO2) below 90% when hypoxemia occurs. Clinically, it is difficult to maintain or recover oxygen saturation when it drops. Therefore, preoxygenation is also essential for critically ill patients with a relatively small lung reservoir, as it can help maintain higher and longer oxygen saturation during endotracheal intubation. For this reason, apneic oxygenation was proposed in the 1950s as a method of oxygen delivery during general anesthesia for surgery, and clinical randomized controlled trials (RCTs) applying it to critically ill patients in the ICU have been conducted since 20 years ago. In an observational study by Macamn et al., the adjusted odds ratio (OR) of a bag valve mask was 1, while that of a high-flow nasal cannula (HFNC) was 5.75 and that of non-invasive ventilation (NIV) was 0.10 when different preoxygenation methods were used. n FLORARI 2, a large-scale clinical RCT comparing NIV and HFNC with or without apneic oxygenation, NIV was significantly more effective than HFNC in reducing severe hypoxemia. Based on these previous studies, the investigators can infer that supplying oxygen during laryngoscopy is not very effective in preventing hypoxemia in critically ill patients. However, there is no guideline on which device to choose for preoxygenation in the ICU, and NIV or HFNC are selected according to the operator's preference. This is because few studies have examined the physiological effects of these devices on patients. Therefore, in this study, the investigators aim to compare the clinical outcomes and adverse events of NIV and HFNC as preoxygenation methods for endotracheal intubation in critically ill patients with acute respiratory failure and to evaluate their physiological effects using electrical impedance tomography.

Study Overview

• Status: Withdrawn
• Conditions: Acute Hypoxemic Respiratory Failure
• Intervention / Treatment: Device: HFNC

• Study Type: Interventional
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Ryoung Eun Ko, MD, PhD; Phone Number: +82-2-3410-6399; Email: koryoungeun@gmail.com
• Study Contact Backup: Name: Eun Jeong Choi; Phone Number: +82-2-3410-6399; Email: graceejchoi@gmail.com

Study Locations

• Korea, Republic of
  • Gangnam
    • Seoul, Gangnam, Korea, Republic of, 06351
      • Samsung Medical Center
      • Contact: Hye Rim Chung; Phone Number: +820234106399; Email: hyerim37.jeong@samsung.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adult patients aged 18 or older
• Acute respiratory failure is defined as follows: Tachypnea over 30 breaths/minute / Symptoms or signs of respiratory failure / PaO2/FiO2 less than 300
• When there is an indication for endotracheal intubation for mechanical ventilation
• When sufficient information and a consent form for the study are obtained from the patient or the patient's guardian

Exclusion Criteria:

• Coma with Glasgow score < 8
• Endotracheal intubation during CPR
• Contraindications for NIV: poor patient cooperation, recurrent vomiting, GI bleeding, severe craniofacial injury, upper airway obstruction, etc.
• Contraindications for RSI: complete upper airway obstruction, severe trauma obscuring cervical structures, etc.
• Implanted electronic medical devices (defibrillator, pacemaker or spinal cord stimulator)
• Skin damage or inadequate electrode contact due to wound dressing at the electrode site
• BMI > 50
• Polydipsia
• Unmeasurable SpO2
• Pregnancy or lactation

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: NIV; Non-invasive ventilation application for preoxygenation
Active Comparator: HFNC; High flow oxygen therapy application for preoxygenation	Device: HFNC; High-flow oxygen therapy before intubation for preoxygenation

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Lowest SpO2	Minimum SpO2 value during endotracheal intubation	at day1(before, during and after preoxygenation and at 5 minutes and at 30 minutes after intubation)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
EIT measurement	Change of T2-T1	at day1(before, during and after preoxygenation and at 5 minutes and at 30 minutes after intubation)
EIT measurement	Change of △EILI	at day1(before, during and after preoxygenation and at 5 minutes and at 30 minutes after intubation)
EIT measurement	Change of △EELI	at day1(before, during and after preoxygenation and at 5 minutes and at 30 minutes after intubation)
EIT measurement	Change of Overdistension	at day1(before, during and after preoxygenation and at 5 minutes and at 30 minutes after intubation)
EIT measurement	Change of Collapse	at day1(before, during and after preoxygenation and at 5 minutes and at 30 minutes after intubation)
EIT measurement	Change of Global Inhomogeneity Index	at day1(before, during and after preoxygenation and at 5 minutes and at 30 minutes after intubation)

Collaborators and Investigators

• Sponsor: Samsung Medical Center

Study record dates

Study Major Dates

• Study Start (Estimated): August 1, 2023
• Primary Completion (Estimated): February 28, 2024
• Study Completion (Estimated): July 30, 2024

Study Registration Dates

• First Submitted: July 3, 2023
• First Submitted That Met QC Criteria: July 18, 2023
• First Posted (Actual): July 27, 2023

Study Record Updates

• Last Update Posted (Actual): April 17, 2024
• Last Update Submitted That Met QC Criteria: April 15, 2024
• Last Verified: April 1, 2024

More Information

Terms related to this study

• Keywords: preoxygenation; intubation; electrical impedence tomography
• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Respiration Disorders; Respiratory Insufficiency
• Other Study ID Numbers: PreoxyEIT

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No