Tingling After the Safety Stop
You are the divemaster on a charter boat 25 minutes from shore. A diver surfaces from a 35 m dive with 42 minutes of bottom time. They admit they skipped the safety stop because their cylinder was down to 50 bar and they felt 'a bit odd.' Ten minutes after surfacing, they complain of tingling in the left hand and dizziness. They are conscious, breathing, and sitting on the bench. The boat has a demand-valve oxygen kit, an AED, a first-aid kit, and marine VHF radio; there is no cell signal. Sea state is 1 m, wind 12 knots. The nearest hyperbaric chamber is 90 minutes away by boat and ambulance. One other diver has a headache but no other symptoms. The boat captain is experienced but has asked you to take the lead on the medical response.
1. What is your initial assessment and immediate action?
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Treat this as a possible decompression illness (DCI) until proven otherwise. The profile-35 m for 42 minutes, missed safety stop, rapid ascent from the stop-plus tingling and dizziness after surfacing is a classic warning pattern. Do not wait for the symptoms to 'settle.'
- Airway, breathing, circulation: confirm the diver is conscious, breathing, and has a pulse. They are sitting and talking, so ABCs are intact, but reassess continuously.
- 100% oxygen: start demand-valve oxygen at 15 L/min (or the kit's maximum) with a tight-fitting mask. Oxygen is first aid for DCI and should be started immediately, not after the boat reaches shore.
- Position: lay the diver flat if tolerated; do not let them walk around. If they are vomiting or short of breath, allow a comfortable position, but avoid upright if they become dizzy.
- Keep warm, monitor, record: note times, symptoms, dive profile, gas, and any change. Ask about weakness, numbness, vision, hearing, chest pain, or confusion. Check the other diver with a headache separately-do not assume it is unrelated.
2. What is your communication and evacuation plan?
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Use the marine VHF, not a cell phone. Call the Coast Guard or local emergency service on the distress channel, state 'possible decompression illness,' give the boat's position, the diver's condition, and the nearest hyperbaric chamber. Request a helicopter or fast boat if the chamber is 90 minutes away by boat and ambulance; the goal is to reduce time to recompression, not to finish the trip. The captain should head for the nearest suitable pickup point while you manage the diver. Ask the emergency service which chamber is open and whether they want the diver on oxygen continuously. Do not delay for a 'wait and see' period. If the diver's condition worsens-loss of consciousness, seizures, chest pain-update the Coast Guard and be ready for CPR/AED. Keep the oxygen running during transfer if trained and equipped. Record everything for the receiving medics.
3. What should you not do, and how do you manage the other diver?
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Do not: put the diver back in the water for 'recompression,' give aspirin or any medication unless directed by a medical professional, let them walk or exert themselves, or delay oxygen while you debate the diagnosis. Do not tell them 'it's just a headache' or that tingling is normal. Do not use a non-rebreather mask if the demand valve is available and the diver can tolerate it; demand valve is preferred for breathing divers. For the other diver with a headache: assess with the same ABCs, ask about the dive profile, hydration, and any visual or neurological symptoms. A headache alone is often benign, but in a diving context it can be a DCI symptom. Keep them resting, hydrated if fully alert, and under observation. If any neurological symptom appears, treat as a second possible DCI and start oxygen. Do not let the headache diver drive or dive again that day without medical clearance.