Biogenic amine/metabolite response during in-flight emergencies

Urine excretion of epinephrine (E), norepinephrine (NE), dopamine (DA), serotonin (5HT) and the metabolites vanillylmandelic acid (VMA), 4-hydroxy-3 methoxyphenylglycol (MHPG), homovanillic acid (HVA), 3, 4-dihydroxyphenylacetic acid (DOPAC), and 5-hydroxyindoleacetic acid (5-HIAA) was determined for students (n = 19) and instructors (n = 21) involved in flying training in-flight emergencies. Timed urine samples were analyzed using high-performance liquid chromatography with electrochemical detection. Basal excretion rates were determined at a later date. Four indices showed significant alteration during the emergencies. Epinephrine and the sum of epinephrine plus norepinephrine increased, the ratio dopamine/norepinephrine decreased and the ratio norepinephrine/serotonin increased. Instructors and students differed only in that VMA and the sum VMA plus MHPG were higher in students. Among the emergencies monitored, smoke and fumes in the cockpit and mechanical problems caused the greatest stress responses.