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*** This is an Emergency Facility and is operational 24 hours, 7 days a week; emergency call-outs can be initiated through the Coastguard (999, channel 16) or the Scottish National Helpline number 0345 408 6008 ***

What are the signs and symptoms of decompression illness?

Decompression illness, or DCI, is a term used to describe illness that results from a reduction in the ambient pressure surrounding a body, typically when you are surfacing during or after a dive. DCI encompasses two diseases, decompression sickness (DCS) and arterial gas embolism (AGE).

AGE is considered the more serious form of DCI. In some cases the diver may have made a rapid ascent, or they may have held their breath during ascent. However, AGE can occur even if ascent appeared completely normal; pulmonary diseases for example, such as obstructive lung disease, may increase the risk of AGE.

The most dramatic presentation of air embolism is the diver who surfaces unconscious and remains so, or the diver who loses consciousness within 10 minutes of surfacing. In these cases, a true medical emergency exists, and rapid evacuation to a treatment facility is crucial.

DCS: the following list ranks the initial manifestations of DCS, from those most commonly to least commonly reported (Vann et al. 2011):

  • Pain, particularly near the joints
  • Numbness or paraesthesia
  • Constitutional concerns — such as headache, light-headedness, unexplained fatigue, malaise, nausea and/or vomiting, or anorexia
  • Dizziness or vertigo
  • Motor weakness
  • Cutaneous, or skin, problems — such as an itch, rash, or mottling ("cutis marmorata")
  • Muscle discomfort
  • Impaired mental status
  • Pulmonary problems — such as breathing difficulties ("the chokes")
  • Impaired coordination
  • Reduced level of consciousness
  • Auditory symptoms — such as hearing sounds that are not there or having a hard time hearing
  • Lymphatic concerns — such as regional swelling
  • Bladder or bowel dysfunction — such as retention of urine
  • Compromised cardiovascular function

According to this recent review, pain and numbness, also known as paraesthesia, were reported initially in nearly two-thirds of cases of DCS, constitutional symptoms in approximately 40 percent of cases, dizziness/vertigo and motor weakness in approximately 20 percent, and cutaneous symptoms in approximately 10 percent (Vann et al. 2011).

Reference: “Decompression illness” by Richard D Vann, Frank K Butler, Simon J Mitchell, Richard E Moon. Lancet 2011; Volume 377, ISSUE 9760, P153-164.

What should I do if I suspect decompression illness?

In the event of a Diving Accident:

  • Keep the casualty lying down
  • Give 100% oxygen by tight fitting mask
  • Rehydrate with electrolyte solution, or best possible alternative, e.g., sports drinks, water, etc.
  • Keep the patient comfortable

Perform a Neurological Test if time allows and record responses.

Be ready to give the emergency services the following information:

  • Age of Diver
  • Condition - Improving/ Stable/ Worsening/ No problems
  • Muscle Weakness - Can the diver stand/ walk, are their arms weak

Sea Diving: Call the Coastguard, DSC or VHF Channel 16/Dial 999 (24 hrs). Then call the National Diving Accident Helpline on 07831 151 523 (24 hrs) in England and Wales or 0345 408 6008 in Scotland.

On Land: Please contact your nearest available BHA member chamber. If you do not know the location of your nearest BHA member chamber then please call the 07831 151 523 (24 hrs) in England and Wales or 0345 408 6008 in Scotland.

If the patient is seriously unwell or deteriorating rapidly, inform the emergency services promptly by dialing 999 on land or VHF Channel 16 if at sea. If you decide to proceed to your nearest Accident and Emergency Department you must still inform the emergency services.

West Scotland Centre for Diving and Hyperbaric Medicine »