Home
Resources
Publications
Arterial Oxygen Saturation, Pulse Oximetry, and Cerebral and Tissue Oximetry in Hypobaric Hypoxia

Arterial Oxygen Saturation, Pulse Oximetry, and Cerebral and Tissue Oximetry in Hypobaric Hypoxia

William Ottestad, Jan Ivar Kåsin, Lars Øivind Høiseth

Aerosp Med Hum Perform. 2018 Dec 1;89(12):1045-1049.

PMID: 30487024

Abstract:

INTRODUCTION: Clinical accuracy of pulse oximeters (giving Spo₂) is routinely tested down to an Sao₂ of 70%, but lower oxygen saturations are often experienced during hypobaric hypoxia. Cerebral (Sco₂) and peripheral tissue (Sto₂) oxygen saturations can be measured using near infra-red spectroscopy. In a project simulating oxygen system failure during high altitude-high opening parachuting (HAHO), Sao₂, Spo₂, Sco₂, and forearm Sto₂ were measured. The aim of the present analysis was to explore the agreement between Sao₂ and the three noninvasive measurements of hypoxemia (Spo₂, Sco₂, and Sto₂).METHODS: Healthy volunteers from the Norwegian Special Operations Commando were studied in a hypobaric chamber as supplemental oxygen was removed at 301 hPa ambient pressure (30,000 ft) and recompressed at 25 hPa · min-1 (1000 ft · min-1) to ground level simulating a HAHO parachute flight. Sao₂ was compared with Spo₂, Sco₂, and Sto₂ in scatterplots and Bland-Altman plots, calculating bias and limits of agreement (LOA).RESULTS: The bias ± LOA were: Sao₂ vs. Spo₂: -5.8% ± 16, Sao₂ vs. Sco₂: -3.4% ± 11, and Sao₂ vs. Sto₂: 17% ± 30. The bias for Sao₂ vs. Spo₂ was dependent on the range of values, and correcting for this with a sloped bias line reduced the LOA to ± 8.2%.DISCUSSION: There were wide limits of agreement between Sao₂ and Spo₂. Sao₂ and Sco₂ agreed better, whereas Sao₂ and forearm Sto₂ had wide LOA. The agreement between Sao₂ and Spo₂ improved when correcting for the underestimation of Spo₂ at low values. There is a poor agreement between Spo₂ and the gold standard Sao₂ during extreme hypobaric hypoxemia.Ottestad W, Kåsin JI, Høiseth LØ. Arterial oxygen saturation, pulse oximetery, and cerebral and tissue oximetry in hypobaric hypoxia. Aerospace Med Hum Perform. 2018; 89(12):1045-1049.

Chemicals Related in the Paper:

Catalog Number	Product Name	Structure	CAS Number	Price
AP1052236868	(S)-5-Allyl-2-oxabicyclo[3.3.0]oct-8-ene		1052236-86-8	Price
AP74046074	S(+)-γ-Vigabatrin		74046-07-4	Price

As a specialist in analytical chemical Products, Alfa Chemistry offers consumers a wealth of raw materials and a full range of technologies and services.

QUICK LINKS

HEADQUARTERS

Tel:

Fax:

Email: