Decompression sickness (the bends): symptoms and first aid

Divers Alert Network lists these symptoms (what the diver feels):

• unusual fatigue
• itchy skin
• pain in joints or muscles
• dizziness, vertigo or ringing in the ears
• numbness, tingling or paralysis
• shortness of breath

…and these signs (what others can see):

• blotchy skin rash
• muscle weakness or paralysis
• difficulty urinating
• confusion or personality changes
• staggering
• coughing up bloody, frothy sputum
• collapse or unconsciousness

According to DAN, symptoms can begin immediately after surfacing or up to 24 hours later; on average they appear between 15 minutes and 12 hours after the dive.

• Give emergency oxygen right away — for every suspected case.
• Serious symptoms (profound dizziness, drifting in and out of consciousness, weakness, trouble walking or breathing): 100% oxygen and evacuation to the nearest medical facility. Call emergency medical services first, then DAN.
• Severe or worsening pain: 100% oxygen and fluids. DAN advises not giving pain relievers unless medical personnel tell you to.
• Mild or slowly developing symptoms: still contact DAN or a doctor trained in diving medicine for an evaluation.

Oxygen can make symptoms improve for a while and then return, so it never replaces a medical evaluation.

Recompression in a hyperbaric chamber is the definitive treatment. DAN advises that a diver with severe DCS is first stabilised at the nearest medical facility before transfer to a chamber.

Our boats carry emergency oxygen and a first-aid kit. In an emergency, call local emergency services first, then DAN; medical teams arrange stabilisation and any transfer to a chamber. Transfer times depend on the boat's location and conditions.