09/12/2024
( Very important study ) 🫨🪽Taravana syndrome, form of neurological decompression sickness that is most frequently seen in breath-hold divers. Taravana syndrome was first described in the 1960s in pearl divers in the South Pacific and among Danish and Norwegian navy personnel who participated in submarine escape training. Taravana syndrome is caused by the accumulation of nitrogen gas in the body, which occurs as a result of rapid succession of repeated breath-hold dives, potentially down to depths as great as 50 metres (about 165 feet) and with intervals of only a few seconds to two minutes between dives.
Minor symptoms of taravana syndrome include headache, dizziness, and nausea. In more severe cases, in which the central nervous system is more extensively affected, symptoms range from pain, partial paralysis, and visual, hearing, or speech impairments to loss of consciousness and death. Symptom onset may be immediate or may occur one to two hours after successive breath-hold dives.
Taravana syndrome can be prevented by incorporating longer surface intervals between dives, each interval lasting 5 to 10 minutes. During this time, some of the nitrogen accumulated from the previous dive is off-gassed from the body, allowing the diver to more safely complete a subsequent dive. Taravana syndrome is treated by recompression in a hyperbaric chamber, followed by gradual decompression.
beriberi, nutritional disorder caused by a deficiency of thiamin (vitamin B1) and characterized by impairment of the nerves and heart. General symptoms include loss of appetite and overall lassitude, digestive irregularities, and a feeling of numbness and weakness in the limbs and extremities. (The term beriberi is derived from the Sinhalese word meaning “extreme weakness.”) In the form known as dry beriberi, there is a gradual degeneration of the long nerves, first of the legs and then of the arms, with associated atrophy of muscle and loss of reflexes. In wet beriberi, a more acute form, there is edema (overabundance of fluid in the tissues) resulting largely from cardiac failure and poor circulation. In infants breast-fed by mothers who are deficient in thiamin, beriberi may lead to rapidly progressive heart failure.
The cardiac symptoms, in both infants and adults, generally respond promptly and dramatically to the administration of thiamin. When neurological involvement is present, the response to thiamin is much more gradual; in severe cases, the structural lesions of the nerve cells may be irreversible.
neuropathy, disorder of the peripheral nervous system. It may be genetic or acquired, progress quickly or slowly, involve motor, sensory, and autonomic (see autonomic nervous system) nerves, and affect only certain nerves or all of them. It can cause pain or loss of sensation, weakness, paralysis, loss of reflexes, muscle atrophy, or, in autonomic neuropathies, disturbances of blood pressure, heart rate, or bladder and bowel control; impotence; and inability to focus the eyes. Some types damage the neuron itself, others the myelin sheath that insulates it. Examples include carpal tunnel syndrome, amyotrophic lateral sclerosis, poliomyelitis, and shingles. Causes include diseases (e.g., diabetes mellitus, leprosy, syphilis), injury, toxins, and vitamin deficiency (e.g., beriberi). See also neuralgia; neuritis. AIDA Freediving Alexandria - Egypt
