Investigation on Alternobaric Vertigo of Gradational Simulated Saturation Diving with the Deepest Saturation of 480m to -493m

Abstract

Objective To provide medical support for deep helium-oxygen saturation diving. Methods According to the data, the diagnostic criteria of Alternobaric vertigo were established. Gradational simulated saturation diving at 65 m, 250 m and 480m helium-oxygen saturation -493 m (hereinafter referred to as 480 m) in 500m saturation system, questionnaire, physical examination, Nystagmus view detector and Magnetic resonance imaging were used to check divers before and after each pressure exposure. Results 1 person at 250m and 480 m after leaving the cabin each had hyposmia, and 1e person at 250m and 480 m after leaving the cabin each had knee reflex (+), but the two sides were symmetrical. 1 person at 250m and 480 m after leaving the cabin each had finger nose test (+), and 1 person at 480 m after leaving the cabin had heel-knee-tibia test (+). 1 person at 65m, 250m and 480 m after leaving the cabin each had hyperemia in the eardrum, and 1 person at 250m and 2 people at 480 m after leaving the cabin had caloric test (+), all on the right side. 2 people at 250m and 480m after leaving the cabin each were found to be impaired by electrical audiometry. All the abnormal people above were reexamined normal the next day. When the pressure changed, there were 5 person-times of dizziness (13s on average), 4 person-times of aural fullness (177.5s on average), 7 person-times of shaking sensation (337.14s on average), 5 person-times of nausea (312s on average), 3 person-times of dizziness (15min on average), 1 person-time of headache in total (20s), 6 person-times of Romberg and 2 person-times of Fukuda in total. Alternobaric vertigo was diagnosed 1 person-time and most likely 1 person-time at 65m, 2 person-times and most likely 2 person-times at 250m and 3 person-times at 480m. Conclusion Alternobaric vertigo occurs frequently in deep helium-oxygen saturated diving, which is characterized by short time, complete reversibility and no influence, but should be paid attention to.