Unexpected Arielle Filiberti MD UCSF Fresno Wilderness Fellow WMS Winter Conference: GME Mini-Lectures A Brief History of (DCI)

• New technology: the Caisson • Developed in 1792 • Compressed air used to force out water and debris

• Allowed construction of the Brooklyn Bridge and Eads Bridge A Brief History of DCI

• The Bends • Musculoskeletal

• The Chokes • Respiratory

• The Staggers • Neurologic Cliffs Notes: Decompression Illness

1. • Air spaces do not equilibrate to pressure changes • Volume of air contracts or expands • Can occur with ascent or descent • Ear, sinus, and dental • Pulmonary • Arterial gas embolism

2. • As decreases, gas bubbles form • Pain, pruritis • Venous gas embolism and ischemia • Increased risk flying after a “dive” or other event Modern Compressed Air Workers (CAW’s)

• CAW’s regulated by OSHA • Tunnel building • Nuclear power plants • Plane inspectors

• CDC claims decompression guidelines are inadequate • CAW’s are left at risk In-Flight Decompression Illness

• Cabins pressurized equivalent 7,000-8,000’

• Failure to pressurize during ascent

• Unanticipated loss of cabin pressure • Large cabins provide “buffer” • Small cabins can decompress in <0.5 second

Military Training

• Depressurization training to simulate and unanticipated loss of cabin pressure • Sudden loss of pressure from 4,000 to 18,000 ft

• Increased risk with commercial flight after this training • Case report of 3 trainees requiring hyperbaric chamber after a commercial flight home

Ground Level Cabin Malfunction

• 4 case reports of uncontrolled cabin pressurization while grounded • Can result in severe DCI needing hyperbaric chamber Take-home Points

1. Consider DCI in any situation where pressure differentials exist 2. Patients can present distant from where the decompression happened 3. Treatment is the same regardless of etiology • IV fluids • Oxygen • Hyperbaric chamber 4. Call DAN! References

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