Related Experiment Video
Updated: Jun 5, 2026

A Model to Simulate Clinically Relevant Hypoxia in Humans
Published on: December 22, 2016
Hypoxic challenge assessment in individuals with obstructive sleep apnea
Masood Ali1, Ian E Smith, Atul Gulati
1Respiratory Support and Sleep Centre, Papworth Hospital NHS Foundation Trust, Papworth Everard, Cambridge CB23 3RE, UK.
Background:
The degree of arterial hypoxemia during air travel in individuals with obstructive sleep apnea (OSA) is not known. The Aerospace Medical Association considers a ground level arterial oxygen tension (PaO₂) above 9.3 kPa as safe before air travel.
Methods:
Fifteen subjects with untreated OSA (mean apnea-hypopnea index [AHI] 43/h) and 14 with treated OSA (mean AHI on CPAP 1.9/h) completed an assessment including hypoxic challenge test (HCT). The groups had similar mean age, mean BMI and pre-treatment OSA severity.
Results:
Four subjects, all in the untreated group and with resting PaO₂ >9.3 kPa and oxygen saturation (SpO₂) >95%, had a positive HCT (PaO₂ <6.6 kPa and/or SpO₂ <85%). The PaO₂ at the end of the HCT was significantly correlated with the minimum overnight SpO₂ (r=.754, p=.002) but not with the daytime PaO₂ and SpO₂. Using a cut off value of 65%, the minimum overnight SpO₂ had positive and negative predictive values of 57% and 100% respectively.
Conclusions:
OSA can be an additional risk factor for developing significant arterial hypoxemia during HCT. Baseline PaO₂ and SpO₂ did not predict arterial hypoxemia during the HCT. Minimum overnight SpO₂ <65% may be used as a cut off to advise further assessment. Effective treatment of OSA seems to be the best option before air travel.
More Related Videos
07:54Drug-Induced Sleep Endoscopy (DISE) with Target Controlled Infusion (TCI) and Bispectral Analysis in Obstructive Sleep Apnea
Published on: December 6, 2016
08:35Oxygenation-sensitive Cardiac MRI with Vasoactive Breathing Maneuvers for the Non-invasive Assessment of Coronary Microvascular Dysfunction
Published on: August 17, 2022
Related Concept Videos
Sleep Apnea
The condition is more prevalent among...
Physical Assessment of the Respiratory Tract II: Inspection
Chest Configuration
The chest configuration can...
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...
Assessment of Airway, Skin Color, and Use of Accessory Muscles
Introduction
The initial evaluation of a patient's respiratory system...
Chronic Obstructive Pulmonary Disease-IV: Assessement and Diagnostic Studies
Medical History
Assessment of Respiration
Subjective Assessment: Nurses interview the patient to gather information directly during the subjective assessment. It includes questions about the individual's medical history, medications, and symptoms, focusing on past respiratory conditions like asthma or COPD,...