Identifying decompression sickness (DCS) as a dive professional can be tough. Is a student diver tired because of working really hard during the course or is the diver’s fatigue a symptom of DCS from the last deep dive? The good news is that DCS is exceptionally rare in well-managed certification courses of all levels, and the most serious types of DCS that require immediate response are often quite obvious.
Making a judgment call about what may or may not be DCS in the moment may be difficult, but you can improve your readiness by reviewing the signs and symptoms. Keep in mind that any sign or symptom that could indicate a decompression injury warrants a thorough examination by a healthcare professional. If there’s ever any question, a set of qualified eyes can only help the situation and the diver.
Type 1 DCS
Type 1 DCS is most typically characterized by musculoskeletal pain and/or mild skin symptoms. Common manifestations include itching and mild rashes (distinctly different from the pinkish blue mottled or marbled and raised skin – cutis marmorata – which may indicate more serious Type 2 DCS) and musculoskeletal pain, particularly in large joints. Less common symptoms include obstruction of the lymphatic system that can result in swelling and localized pain in the armpits or groin or behind the ears. Symptoms of Type 1 DCS can build in intensity. A diver who initially reports a mild joint ache may report serious pain shortly thereafter. Pain associated with DCS typically does not increase with movement, although immobilizing a painful joint can reduce discomfort.
Type 2 DCS
The symptoms of Type 2 DCS are considerably more serious and typically fall into one of three categories: neurological, inner ear and cardiopulmonary.
- Paresthesia (a burning, tingling or prickling sensation typically felt in the extremities)
- Muscle weakness
- Difficulty walking/impaired gait
- Problems with physical coordination or bladder control
- Loss of consciousness
- Confusion or impaired mental status
- Hearing sounds that do not exist
- Tinnitus (ringing in the ears)
- Hearing loss
- Dizziness or vertigo (sensation of spinning)
- Nausea and vomiting
- Impaired balance
- “The Chokes” (dry cough and difficulty taking a breath)
- Chest pain (particularly behind the sternum)
- Dyspnea (difficulty breathing)
Type 2 DCS can develop either slowly or rapidly, and progression is difficult to predict. Slowly building symptoms can obscure the seriousness of the situation and provide an opportunity for the diver to deny issues or the severity of injury. Fatigue and weakness are relatively common after diving, and if their onset is protracted they can be easily ignored. More serious symptoms such as difficulty walking, urinating, hearing or seeing can prompt more rapid recognition of injuries. Divers are frequently reluctant to report symptoms, which is vital for you to keep in mind. Students frequently fail to report, or underreport, symptoms for fear of judgment or “making a big deal out of nothing.”
If you suspect that you or a student has any symptoms that could potentially indicate DCS, get an evaluation by a medical professional as soon as possible. Treating a noninjury as if it were quite serious has minimal repercussions, but failing to respond appropriately to an acute case of DCS can cause serious long-term harm to an injured diver.
For more information about DCS and diving visit DAN.org/Health.