Related Experiment Video
Updated: Aug 17, 2025

Drug-Induced Sleep Endoscopy DISE with Target Controlled Infusion TCI and Bispectral Analysis in Obstructive Sleep Apnea
Published on: December 6, 2016
Efficacy of preoxygenation with end-tidal oxygen when using different oxygen concentrations in patients undergoing
Jaewoong Jung1, Seri Park1, Misoon Lee1
1Department of Anesthesiology and Pain Medicine, Soonchunhyang University Bucheon Hospital, Soonchunhyang University College of Medicine, Bucheon, Republic of Korea.
Background:
Preoxygenation is a simple but very important procedure for preventing arterial desaturation. A higher fraction of inspired oxygen (FiO2) increases atelectasis and 80% oxygen results in significantly less atelectasis than 100% oxygen. We investigated whether there was a difference in the duration of adequate preoxygenation when using 100% and 80% oxygen. The proportion of patients for whom >3 min was required to achieve adequate preoxygenation was also investigated.
Methods:
The VitalDB database of patients underwent general surgery between February 1, 2021 and November 12, 2021 was reviewed. The time between the start of preoxygenation and the point where a 10% difference between FiO2 and end-tidal oxygen (EtO2) was defined as the preoxygenation time. The patients were classified into 100% and 80% groups according to the oxygen concentration. Propensity score matching (PSM) was performed to control for potential confounding factors.
Results:
Only 330 of the 1,377 patients had sufficient data for analysis: 179 in the 80% group and 151 in the 100% group. After PSM, 143 patients in each group were analyzed. The median preoxygenation time was 143 s [interquartile range (IQR): 120.5-181.5 s] and 144 s (IQR: 109.75-186.25 s) in the 80% and 100% groups, respectively [P=0.605; median difference =-1 s; 95% confidence interval (CI): -13 to 10]. Of the patients, 27% required >3 min for adequate preoxygenation.
Conclusions:
No difference in preoxygenation time was found between the 80% and 100% groups. For some patients, breathing for 3 min is not sufficient for adequate preoxygenation. EtO2 monitoring aids evaluation of whether preoxygenation was adequate.
More Related Videos
05:43Topical Airway Anesthesia for Awake-endoscopic Intubation Using the Spray-as-you-go Technique with High Oxygen Flow
Published on: January 13, 2017
07:38Design and Development of a Model to Study the Effect of Supplemental Oxygen on the Cystic Fibrosis Airway Microbiome
Published on: August 3, 2021
Related Concept Videos
Treatment for Pulmonary Arterial Hypertension: Oxygen Therapy for Respiratory Failure
Oxygen therapy is vital in increasing and maintaining blood oxygen levels in PAH patients. As a result, it aids in reducing fatigue,...
Administering Oxygen by Mask
Administering oxygen by mask is a common nursing intervention that provides supplemental oxygen to patients with respiratory distress or chronic lung conditions. This procedure involves delivering oxygen at a specified rate through a face mask connected to an oxygen source.
Equipment
The equipment necessary for this procedure includes:
Oxygen Delivering System II: Venturi Mask and Transtracheal Oxygen
Venturi Mask
The Venturi mask, named after the Venturi effect, is designed to deliver precise oxygen concentrations. It consists of a large tube with an oxygen inlet that narrows down, causing a pressure drop that pulls air in through adjustable side ports. The mask is a lightweight,...
Oxygen Delivering System I: Nasal Cannula and Face Mask
Nasal Cannula
A nasal cannula is a lightweight tube split at one end into two prongs and placed in the nostrils. It is typically used to deliver low to medium levels of oxygen.
Suggested flow rate: The suggested flow rate for a nasal cannula typically ranges between 1 and 6 L/min.
Oxygen percentage setting:...
Assessment of Diffusion and Perfusion
The Role of Diffusion in Respiration
Diffusion is the process by which molecules move from an area of higher concentration to an area of lower concentration. In the respiratory system, this...
Respiratory Assessment: Purpose and Indications
Objectives and Importance:
The primary goal of respiratory assessment is to evaluate patients at early risk of clinical deterioration. Since respiratory distress often precedes other signs of declining health, breathing patterns and sounds become a...