symptoms seemed to worsen with ambulation. The patient’s blood pressure, pulse, and respirations were within normal limits; he was mildly diaphoretic and pale; oxygen saturation was 98 percent. He was fully alert and fully oriented. Mini mental status exam was grossly normal except for difficulty in performing serial sevens, which is completed by subtracting seven from 100, serially. The remainder of his neurological exam was normal. An arterial blood gas analysis demonstrated mild respiratory alkalosis but normal PaO2 and PaCO2. Following a review of the case by carrier medical staff and a remote consult with an Undersea Medical Officer (UMO), it was determined that decompression sickness (DCS) was the likely diagnosis and an emergent medical evacuation for recompression therapy at U.S. Naval Ship Repair Facility and Japan Regional Maintenance Center (SRF-JRMC) in Yokosuka, Japan was authorized. The patient was evacuated from the carrier via helicopter whose low altitude flight was beneficial to transporting a patient with DCS. During the flight, the patient received continuous intravenous rehydration and oxygen from the escorting flight surgeon and Hospital Corpsman. The helicopter was met by a waiting U.S. Naval Hospital Yokosuka ambulance and UMO. The patient reported no additional symptoms following the flight, however, he remained abnormally fatigued and continued to report grogginess and difficulty concentrating. U.S. Navy Treatment Table Six Recompression Profile was ordered and completed in the SRF-JRMC hyperbaric chamber without complications. After two cycles of treatment, the patient reported complete resolution of his symptoms and reported feeling “great!” The patient was observed for one hour and demonstrated no residual effects or recurrence of symptoms. Per the U.S. Navy Aeromedical Reference
FALL 2010
and Waiver Guide he was released and returned to flight duty 14 days later. Pilots are required to wear face masks providing supplemental oxygen air from engine start to shut down. The oxygen is provided by an On Board Oxygen Generating System (OBOGS). The pressure in the cockpit is maintained above ambient atmospheric pressure by the Environmental Control System. The risk of decompression injury increases as the pressure in the cockpit drops, especially when the pressure drops rapidly. In this case the pressure in the cockpit dropped precipitously as the relative cab-
in altitude went from 10,000 feet to his actual altitude of 30,000 feet in seconds. Type I and II DCS can result any time a person moves through an atmospheric pressure gradient. While more common during underwater diving, DCS can occur at high altitude as well. If recognized and treated appropriately, DCS usually resolves completely and is seen as an occupational hazard for people without other risk factors such as age. In this case, the patient was successfully treated utilizing all available resources and was returned to full flight status in short order.
PACIFIC OCEAN - Hospital Corpsman 1st Class Salvador Lopez, from Coachella Valley, Calif., organizes surgical tools before an oral surgery in a dental department operating room aboard the aircraft carrier USS George Washington (CVN 73). Photo by Mass Communication Specialist 3rd Class Jacob D. Moore.
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