Decompression sickness: why divers need hyperbaric chambers
Southwest Florida's waters draw plenty of scuba divers. Hyperbaric chambers were originally developed for them, and they're still the frontline treatment for diving injuries.
What is decompression sickness?
When you dive, the pressure of the water makes your body absorb extra nitrogen from the air you breathe. If you come up too quickly, that nitrogen can come out of solution as bubbles in your blood and tissues, like opening a shaken soda. This is decompression sickness (DCS), often called "the bends."
A related emergency, arterial gas embolism, happens when air from an overexpanded lung enters the bloodstream, often from holding your breath on the way up.
Symptoms
Symptoms usually appear within minutes to a few hours after a dive, sometimes later, and can include:
- Joint or limb pain, often in the shoulders or elbows
- Unusual tiredness
- Numbness, tingling or weakness
- Skin rash or itching
- Dizziness, confusion or trouble speaking
- Shortness of breath or chest pain
- Loss of consciousness
Any neurological symptoms after a dive are an emergency.
What to do
- Call 911.
- Give 100% oxygen if trained and available, and keep the diver lying down.
- Contact the Divers Alert Network (DAN) emergency hotline at +1-919-684-9111. They can advise on care and help locate an appropriate chamber.
Why the chamber works
Recompression in a hyperbaric chamber does two jobs:
- Pressure shrinks the bubbles (Boyle's law), easing blockages and pain.
- Breathing pure oxygen speeds the removal of nitrogen from the body and helps oxygen reach damaged tissue.
Treatment follows specific dive-medicine protocols, often the US Navy treatment tables, in a medical hyperbaric facility. Wellness chambers are not used for diving injuries.
Prevention
- Follow your dive computer or tables and do safety stops.
- Ascend slowly and never hold your breath on the way up.
- Stay hydrated and avoid diving when you're unwell or tired.
- Wait before flying after diving. Common guidance is at least 12 hours after a single no-decompression dive and at least 18 hours after multiple dives or multiple days of diving; longer after decompression dives.
See also Flying, altitude and your oxygen levels.