In 2013, Quinette et al conducted a research to study the effects of hypoxia on pilots1. The study was administered by exposing one group of participants to hypoxic conditions in an experimental chamber and the other group was not. A well-established procedure was administered to test cognitive performance of the subjects from both groups. This article is meta-analysis of the original article.
Table 1 below shows comparison of the oxygen desaturation mean values for different phases of the study. Heart rate results are excluded here since heart rate is not a variable of interest in this study.
|Table 1: Oxygen saturation mean values comparison|
|Phase of the study||Control group||Experimental group|
|Transition (after oxygen starvation)||98.6||1.2% higher|
The results depicted in table 2 show that subjects that were exposed to hypoxic conditions performed badly when memory test was undertaken.
|Table 2: Relationship between hypoxia and cognitive performance|
|Control group||Experimental group|
|Overall performance (correct responses)||Higher (65%)||Lower (35%)|
|Classification of errors (Control v/s experimental group)|
|Omissions||Higher (under hypoxia)|
|Miscalculations||Higher (under hypoxia)|
|Suppression failures||Similar for both groups|
|Error patterns comparison (Control v/s experiment groups)|
|Omissions||3x higher in hypoxia group|
|Suppression||5x higher in hypoxia group|
|Miscalculations||1.5x higher in control group|
This is an exploratory experimental research, to analyse the effects of acute hypobaric hypoxia in young pilots.
The 57 non-smoking young and healthy pilot participants from Department of Medicine Aeronautical Operations in France participated in this study.
Participants were randomly divided into two groups, experimental group and thecontrol group.
- Dependent variable:
- Cognitive performance
- Independent variable:
- Arterial blood oxygen saturation
The independent variable was further classified into three classes:
- Suppression failures; and
- Hypobaric chamber;
- Pulse oximetry sensor; and
- Placed Auditory Serial Additional Test (modified version).
The participants were randomly allocated to one of the study groups (control or experimental). The experimental group was exposed to hypoxic conditions in a simulation chamber and the control group was not. All participants were required to have sufficient sleep before partaking in the study.
A series of single digit numbers were displayed to the participants and they had to add two consecutive numbers displayed. Failing to add them correctly was regarded as an error.
The experiment was divided into three different phases:
- Initial phase;
- Desaturation phase; and
- Oxygen restoration phase.
- The one-way and two-way ANOVA was used to perform data analysis; and
- Correlation between ‘working memory’ performance and the blood oxygen desaturation was also measured.
Due to the convenient sample used for the research, the results may only be applicable to the similar population.