View source for Scuba diving emergencies

==Background==
{{Diving Physiology}}

==Clinical Features==

==Differential Diagnosis==
*Facial/Ear/Eye Pain:
**[[Sinusitis]]
**[[Otitis Media]] and [[Otitis Externa]]
**[[Subconjunctival Hemorrhage]]
**[[Corneal Abrasion]] or [[Corneal Ulcer]]
**Facial bone fracture
*[[Dyspnea]]:
**[[Pneumonia]]
**[[Congestive Heart Failure]]
**Acute Asthma Exacerbation
**[[COPD Exacerbation]]
*[[Chest Pain]]:
**[[Acute myocardial infarction]]
**[[Pericarditis]]
**[[GERD]]
*[[Altered Mental Status]]:
**[[Stroke]]
**[[Meningitis]] or [[Encephalitis]]
**[[Intracerebral Hemorrhage]]
**Toxic Ingestion
{{Scuba diving DDX}}
{{Water related injuries DDX}}

==Evaluation==

==Management==
===Barotrauma of Descent===
*Gradual Ascent, avoidance of diving deeper if experiencing pain
*Decongestants for sinus pain
*Antibiotic ear drops for TM rupture (choose a formulation such as [[ofloxacin]] suspension that is safe in the middle ear)

===Barotrauma of Ascent===
*Gradual ascent, safety stops imperative
*[[Pulmonary barotrauma]] may manifest in many ways<ref>Diving Medicine, Karen B. Van Hoesen and Michael A. Lang, Auerbach's Wilderness Medicine, Chapter 71, 1583-1618.e6</ref>
**Local pulmonary injury and [[pneumomediastinum]] require supportive care only
**Treat [[Pneumothorax]] according to severity, does not require recompression on its own
**If any of the above conditions present with [[altered mental status]], presume [[arterial gas embolism]] and recompress the patient
**[[Arterial gas embolism]] is the most dreaded complication of diving. It can manifest in many ways depending on where the emboli travel (i.e. [[stroke]], [[seizure]], [[acute myocardial infarction]], or [[arrythmia]]. The treatment is immediate hyperbaric oxygen therapy.
**[[Decompression sickness]] (aka the bends) is due to the gas (usually nitrogen) coming out of solution in the blood and tissues secondary to too rapid of an ascent/depressurization. It can present with a myriad of findings, but the most common systems affected are neurologic and musculoskeletal. Those suspected to have this condition should be referred for urgent hyperbaric therapy.

===At Depth Injuries===
*Oxygen Toxicity usually results from high ppO2 at several atmospheres of water pressure; though FiO2 is fixed by the gas mixture the diver selects in common, open-circuit diving, the ppO2 varies with depth due to the effects of Dalton's Law and increased pressure delivered by the regulator to defeat external water pressure. Risk of oxygen toxicity rises above 1.4atm ppO2 and even more sharply above 1.6atm ppO2. 
**It can cause pulmonary injury manifesting as chest pain, pleurisy, or even pulmonary edema/hemorrhage. It can also cause CNS pathology manifesting as nausea, auditory changes, convulsions, sweating, twitching, or tunnel vision. Treatment for any of these injuries is ascent and inhalation of lower ppO2 at decreased pressure. More severe presentations of pulmonary injury may require intubation.
*Nitrogen Narcosis results from inhaling nitrogen containing gas mixtures at high pressures (specialized gas mixtures exist for work at depth that have decreased amounts of nitrogen). It manifests as altered mental status. Treatment is gradual ascent.
*[[Hypothermia]]: re-warm
*[[Carbon Monoxide]] Toxicity: see main section; oxygen, consider hyperbaric therapy
*Caustic Cocktail: supportive

==Disposition==
*Many divers carry insurance covering diving accidents and related medical problems, including costs of transfer for hyperbarics, through the [https://dan.org/health-medicine/medical-services/ Divers Alert Network] - a worldwide, non-profit cooperative dedicated to dive safety. Coverage for transfer costs may require DAN arrange the transfer. Expert consultation over the phone, similar to Poison Control, may also be available. Whether or not you can confirm the patient has such coverage, and unless your facility has hyperbaric treatment available in-house, you should consider contacting them:
**'''Divers Alert Network 24/7 hotline - +1-919-684-9111'''

==See Also==
*[[Diving medicine]]
*[[Hyperbaric medicine]]

==References==

[[Category:Environmental]]