lumbar vertebrae the five vertebrae between the thoracic vertebrae and the sacrum. vertebra magÂ´na the sacrum. odontoid vertebra the second cervical vertebra, or axis. vertebra plaÂ´na a condition of spondylitis in which the body of the vertebra is reduced to a sclerotic disk.
Generally, in the early stages of drowning, very little water enters the lungs: a small amount of water entering the trachea causes a muscular spasm that seals the airway and prevents the passage of both air and water until unconsciousness occurs.
Symptoms and prevention from eHow: 1  The first step in preventing a dry drowning episode is close observation. 2  Monitor the personâs breathing. 3  Check for persistent cough, pain in chest and mood or mental status change.  Dry drowning usually occurs within 1 hour and 24 hours after incident.