The most serious of the many types of dive injuries are Decompression Sickness (DCS) and Arterial Gas Embolism (AGE) / Pulmonary Barotrauma. It is not essential in the field to determine which of these problems is present, as the field treatment and transport considerations are essentially the same.
In many cases and in some of the most serious of dive injuries DCS and AGE, with all their various presentations, will occur concurrently.
Decompression Sickness (DCS)
On ascent, as the body experiences a rapid reduction in ambient pressure and particularly if the diver does not allow adequate time for the elimination of these excess gases, inert gases (e.g. nitrogen) that are dissolved in the tissues may come out of solution as bubbles. These bubbles may form in the venous blood, the musculoskeletal system or other body tissues, with DCS the clinical condition that results.
Type 1 DCS is indicated by symptoms limited to the skin capillaries, lymphatic vessels and musculoskeletal systems. This includes typically skin rashes and joint pain. In mild cases the symptoms may be fleeting and last only a few minutes "niggles” and may not require chamber treatment. Pain at or around joints is rarely symmetrical. The pain of more severe cases usually increases over 12 to 24 hours and if untreated slowly resolves over the next 3 to 7 days to a dull ache.
Type II DCS is more serious in nature and includes all symptoms relating to the central nervous system (CNS), spinal cord and/or cardio/respiratory systems. In many of these cases type 1 symptoms such as joint pain are also present.
Simply stated, Type I and II DCS are progressive and potentially crippling and fatal.
Arterial Gas Embolism / Pulmonary Barotrauma
As the diver ascends, gas in the body will expend in accordance with Boyles Law. If this expansion is not accommodated or controlled, the diver may encounter any one of several serious and painful disorders. These are the most common cause of death in diving accidents and include:
Arterial Gas Embolism
A) Immediate History
Often associated with rapid, buoyant ascent; panic or breath-hold ascent; upper respiratory infections; surface oriented diving in heavy seas; shallow dives; and difficulty equalizing during descent or ascent
Abrupt and dramatic. The diver may be in obvious difficulty on surfacing. A delay in symptom onset of more than 10 minutes post-dive is not consistent with the diagnosis of embolism.
C) Signs and Symptoms
Immediate and dramatic presentation; collapse and unconsciousness; seizure activity; loss of visual field or blindness; weakness or paralysis; disorientation; bloody froth, sputum; chest pain; spinal cord involvement which may be pure motor or pure sensory; death.
A) Immediate History
Often associated with hard working and deep air dives (>30 fsw); long bottom times; cold water dives; repetitive dives; missed safety stops; dehydration and recent alcohol intake. It’s possible to follow tables and still get bent.
Generally more gradual and increasing in severity. Usually within 30 minutes of surfacing and in rare instances delayed a day or more
C) Signs and Symptoms
Joint pain is common complaint (e.g. shoulder, elbow, hip, knee); skin rashes or mottled skin (things other than DCS can of course cause this); in more severe cases the spinal cord is involved more often than the brain; cardiopulmonary effects possible
Patient Position - Dive Injury
The Trendelenberg Position is no longer indicated in the care of dive injuries. It may impair already difficult breathing and lead to increased intra-cerebral swelling. A horizontal position, either supine or 3/4 prone for airway maintenance is preferred.
Carbon Monoxide Toxicity
Due to contaminated air supply. Signs and symptoms include headache, confusion, apathy, drowsiness, nausea, vomiting, shortness of breath, unconsciousness, etc.
Treatment includes remove from source, protect airway, provide 100% oxygen and monitor during transport. Hyperbaric oxygen treatment may be required.
Caused by air trapped beneath a filling or dental work. Signs and symptoms include tooth or facial pain, bleeding or broken tooth. First aid – analgesics as directed and dental repair.
External Ear Barotrauma (squeeze)
Caused on descent by tight hood or outer ear canal blocked by wax. Signs and symptoms include pain not relieved by equalization, discharge or bleeding, or more severe symptoms if ear drum ruptures. Treat as per middle ear baratrauma.
Middle Ear Barotrauma
Caused on descent by inadequate equalization. This may be due to poor technique, diving with a cold, or too rapid a descent. May also be caused on ascent by swelling of the middle ear lining, too rapid an ascent or decongestants wearing off. Signs and symptoms may include discomfort, ear pain during dive, hearing loss, ringing, ruptured drum, vertigo, nausea, vomiting, blood from nose, mouth or ear.
Do not equalize forcefully. No further diving until reviewed. Consult a diving physician. Treatment may include analgesics or decongestants as directed.
Inner Ear Barotrauma
Caused by forceful equalization or severe middle ear barotrauma. Signs and symptoms include vertigo, nausea, vomiting, ringing in ears, hearing loss and usually persist for more than 20 minutes post dive.
Sit patient down, keeping him still and quiet. Avoid exertion, coughing, sneezing or attempts to equalize. Consult diving physician or physician specialist.
Oxygen Toxicity (CNS)
Caused by breathing oxygen at increased partial pressures (usually > than 1.5 atmospheres). The likelihood of Central nervous system oxygen toxicity increases with greater depths (on compressed room air at depths approaching 200 feet or diving with increased O2 gas mixtures as in Nitrox). Signs and symptoms may occur underwater or shortly after surfacing and may include dizziness, nausea, twitching of facial muscles, disorientation, visual abnormalities, unconsciousness or convulsions. Treat as for serious dive injury and provide 100% oxygen during transport to medical aid.
Caused typically during descent (can occur on ascent as well) by equalization problems due to nasal congestion or deformity. Signs and symptoms include facial pain or headache in sinus areas, blood or mucous discharge from the nose.
If discomfort persists, analgesics or decongestants (e.g. snuffling a small amount of saline) as directed by medical advise.
Face Mask Squeeze
Caused by failure to equalise pressure across the mask. Mask suction may result in nose bleeding, facial bruising or bloodshot eyes.
Fish Spine Injuries
Symptoms depend on species (may be venomous). Puncture wounds, pain, bleeding, nausea, vomiting, and shock.
Control bleeding, but remove spine only if loose and easily removed. Clean wound with soap and water and rinse thoroughly. Immerse wound in warm/hot water 30-90 minutes for pain relieve.
Severity can range from irritating to fatal. Symptoms include swelling, redness and itching irritation. Initial wound treatment includes flushing with seawater (not fresh water) while removing any adherent particles, and keeping the part cool. Apply cloths soaked in vinegar or a vinegar based paste to neutralize stingers.
Compiled by John Merrett, Paramedic Specialist