Diving injuries in Thailand: decompression sickness, oxygen and hyperbaric chambers

What decompression illness is

Decompression illness covers two related conditions. Decompression sickness, often called 'the bends', happens when nitrogen absorbed during a dive forms bubbles in the body as pressure falls on ascent. Arterial gas embolism happens when gas enters the arteries, usually after a rapid ascent or breath-holding, and can reach the brain within minutes. Both are emergencies.

Symptoms include joint or limb pain, unusual tiredness, skin rash or itching, numbness, tingling, weakness, dizziness, headache, difficulty walking, breathing difficulty, chest pain, confusion and loss of consciousness. They usually start within a few hours of surfacing but can appear later, including after a flight. Divers often dismiss mild symptoms as muscle strain; if a symptom is new and appeared after diving, treat it as possible decompression illness.

First aid on the boat or shore

Start emergency oxygen straight away, at the highest concentration available, ideally 100% through a demand valve or non-rebreather mask, and keep it going until medical help takes over. DAN's guidance stresses that oxygen should be given promptly for suspected decompression illness, even if symptoms seem to improve.

Lay the diver flat, or on their side if they are drowsy or vomiting, and keep them warm and still. If they are fully conscious and not nauseous, small amounts of water can be given. If they stop breathing normally, start CPR if you are able to.

Call for help: in Thailand, call 1669 for emergency medical services, then the DAN emergency hotline on +1-919-684-9111, which DAN says to contact after local emergency services. DAN can advise the people on the scene and help coordinate with the nearest chamber. Write down the diver's dive profiles from their computer, the gases used, the times of the dives and when symptoms began; the treating doctor will need these.

Do not take the diver back underwater to 'recompress' them, and do not let them fly until a diving medicine doctor has cleared them.

This guide summarises published public-health guidance. It is not a substitute for first-aid training or for the instructions of the 1669 call handler or a doctor; if in doubt, call 1669.

Hyperbaric chambers in Thailand

Recompression in a hyperbaric chamber is the definitive treatment for decompression illness. The diver breathes oxygen at increased pressure, shrinking bubbles and restoring oxygen to affected tissues. The sooner treatment starts, the better the outcome tends to be, though treatment can still help when started late.

Thailand has chambers serving its main dive regions, run by navy, hospital and private operators. In Phuket, for example, Bangkok Hospital Siriroj describes a hyperbaric facility for recreational divers with decompression sickness or arterial gas embolism, serving the west coast and offering 24-hour emergency services. Chamber availability changes, so ask your dive operator which chamber it uses and how it would get you there, and keep that number with your dive kit.

Islands such as Koh Tao and the Similan and Surin marine parks are some distance from the mainland. Evacuation can involve a boat transfer and road journey, which is another reason oxygen on board matters.

Before you dive

The UK government warns that diving schools may have limited resources and do not always observe safety and maintenance standards. It advises asking to see the operator's credentials, checking your insurance conditions, confirming that oxygen is available on the boat, and asking about access to a hyperbaric chamber.

Standard travel insurance may not cover scuba diving, or may cover it only to a certain depth or qualification level, and chamber treatment and evacuation can be very expensive. Check the policy wording, or take out specialist dive insurance. Make sure you are medically fit to dive; some conditions and medicines need a doctor's clearance first.

Dive within your training and your computer's limits, ascend slowly, make safety stops, stay well hydrated and avoid alcohol before diving. Allow enough time between your last dive and your flight home; DAN publishes guidance on flying after diving.

Frequently asked questions

Sources

1. Divers Alert Network — Medical services and emergency hotline
2. Bangkok Hospital Siriroj (Phuket) — Hyperbaric chamber facility
3. GOV.UK — Thailand travel advice: Safety and security
4. GOV.UK — Thailand travel advice: Getting help
5. WHO South-East Asia — National Institute for Emergency Medicine (institute details)