Decompression Illness in a Remote Setting With Limited Chamber Access
A 38-year-old diver on a liveaboard 6 hours from the nearest chamber develops progressive numbness and weakness in both legs 3 hours after a 30 m dive, along with urinary hesitancy. He is otherwise stable, has no chest pain, and is on 100% oxygen by mask. The boat has no physician aboard, the sea is rough, and a helicopter evacuation is possible but will take 4 hours to arrive. The chamber is 6 hours away by boat.
1. What is your assessment and immediate management while awaiting evacuation?
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This is Type II decompression sickness with spinal cord involvement - bilateral leg numbness/weakness plus urinary hesitancy. Immediate management:
- 100% oxygen continuously by tight-fitting mask.
- Supine positioning, keep the patient warm, and avoid exertion.
- IV fluids (isotonic) to support perfusion; treat pain and vomiting.
- Urinary retention: monitor for bladder distention; catheterization may be needed if he cannot void.
- Do not delay evacuation for improvement; oxygen may reduce symptoms but does not replace recompression.
2. Compare helicopter evacuation (4 hours to arrive) with boat transport (6 hours to chamber). What do you choose?
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The helicopter arrives in 4 hours and then must fly to a chamber; the boat takes 6 hours to the chamber. The decision hinges on time to recompression, not time to first contact.
If the helicopter can deliver the patient to a chamber faster than the boat's 6 hours, choose the helicopter. If the helicopter's total time to chamber exceeds 6 hours, the boat may be equivalent or better, and the rough sea makes helicopter transfer risky. The key judgment: calculate time to definitive recompression for each option, account for sea state and patient stability, and keep oxygen running during either transfer. If the patient deteriorates (new chest symptoms, worsening weakness), escalate to the fastest option regardless.
3. The patient's leg weakness worsens during transfer. What does this mean and what do you do?
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Worsening neurological deficit indicates progression of spinal DCS, which is an emergency. It supports the need for urgent recompression and may warrant US Navy Treatment Table 6 on arrival rather than a shorter table.
Actions: maintain 100% oxygen, ensure the receiving chamber is ready, and consider whether a faster transport option can be activated. Do not interpret worsening as a reason to stop oxygen or to wait; it is a reason to expedite. Document the time course of deficits, since it informs the treatment table and prognosis.