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Sub-atmospheric decompression illness
Published in Nicholas Green, Steven Gaydos, Hutchison Ewan, Edward Nicol, Handbook of Aviation and Space Medicine, 2019
Nicholas Green, Steven Gaydos, Hutchison Ewan, Edward Nicol
Breathing gas composition: Higher breathing gas oxygen concentrations are more protective.Hypoxia increases incidence and severity of symptoms (see Figure 8.1).
Rating of perceived exertion with Borg scale in stroke over two common activities of the daily living
Published in Topics in Stroke Rehabilitation, 2018
Maxence Compagnat, Jean Yves Salle, Stephane Mandigout, Justine Lacroix, Nicolas Vuillerme, Jean Christophe Daviet
Post-stroke physical activity is recommended to reduce the patient’s dependency for activities of daily living.1,2 Interventions on the amount of physical activity are based on the dose-response relationship which requires sufficient frequency, duration, and intensity of physical activity.3 Monitoring the frequency and duration of an activity are rather simple tasks; however, quantifying intensity remains an issue in common clinical practice for post-stroke patients. Physicians are advised to measure the intensity of physical activity by analyzing the heart rate (HR), instantaneous O2 consumption (VO2), and the Borg Scale for the rating of perceived exertion (RPE) (3). However, using the HR values remains problematic because of the prevalence of cardiac arrhythmias and blocker treatments. Furthermore, the VO2 is rarely measured in common clinical practice as it requires a breathing gas exchange analyzer.
Is it safe to SCUBA dive with asthma?
Published in Expert Review of Respiratory Medicine, 2019
Megan Dp Gore, Giles Dixon, Andrew E Stanton
On immersion, divers are breathing through a pressurized self-contained underwater breathing apparatus. Compressed gas is stored within a cylinder and inspired by the diver via a pressure regulator. The increase in ambient pressure as the diver descends results in an increase in density of the inhaled gas. A higher density of gas results in increased airway resistance, reduced pulmonary compliance and an increase in work of breathing [20]. Divers can offset this problem by substituting a less dense inert gas (e.g. helium or hydrogen) for nitrogen when descending to extreme depths. However, this practice is not commonly required for the majority of recreational dives. For divers with pre-existing airways disease, the increased work of breathing gas can become problematic.
Firefighters during training as divers: physiologic and psychomental stresses
Published in International Journal of Occupational Safety and Ergonomics, 2022
Thomas Muth, Ingo Hansen, Clark Pepper, Jochen D Schipke
Both recreational and professional scuba divers are confronted with quite a few changes once they are under water, among them being vision, hearing and gravity deprivation. Moreover, the position of the body is unfamiliar, including the mode of locomotion. As it is unnatural for humans to stay under water, scuba diving imposes uncommon environmental stresses on the body such as pressure, cold and gas kinetics in tissues of the body [1]. An increased ambient pressure might create barotrauma, low temperature might lead to hypothermia and breathing gases might exert toxic properties [2]. These kinds of environmental stresses are not often encountered in other types of activity [3]. Not surprisingly, some authors describe scuba diving as being a high-risk sport [4].