diving related injuries

Diving Related Injuries

Amy Gutman MD ~ EMS Medical Directorprehospitalmd@gmail.com /

www.TEAEMS.com

Diving Emergency Categories

Environmental: Hypothermia, sunburn, physical

trauma

Aquatic Activities: Submersion injuries, motion

sickness, envenomations

Scuba Diving Injuries: Pressure changes Breathing gases at elevated

partial pressures Barotrauma Arterial Gas Embolism Decompression Sickness

Today’s lecture focuses on scuba-related injuries & barotrauma

Standard Management Flowchart for Diving-

Related Injuries

Diving Emergencies: Boyle’s Law

The volume of a gas is inversely proportional to it’s pressure if the temperature is constant

Translation: The more pressure exerted on a gas, the less volume of gas there is in a closed container

Dalton’s Law

Total pressure of a mixture of gases is equal to the sum of partial pressures of the individual gases

Translation:Partial Pressure A = 1Partial Pressure B = 2Partial Pressure C = 3A + B + C = 6 (Total

Pressure)

A=1 B=2 C=3

6

Diving Emergencies: Henry’s Law

The amount of gas dissolved in a given volume of liquid is proportional to the pressure of the gas above it

Pressure = 6

1

1

1

1

1

1

Diving Emergencies: Pathophysiology

Henry’s Law: Increased dissolution of gases during descent

Boyle’s Law:Gases have smaller volume in water than on surface

In controlled ascents, gases escape through respiration

In uncontrolled ascents, gases rapidly come out of solution (blood) forming nitrogen bubbles in tissues & organsCommon: brain, skin, inner ear, muscles, joints

Diving Emergencies: Classification

Surface InjuriesStrangulation

Descent InjuriesBarotrauma

Floor InjuriesNitrogen narcosis

Ascent InjuriesDecompression illnessPulmonary overpressure & subsequent arterial gas

embolism, pneumomediastinum, or pneumothorax

BlackoutsDeep Water Blackout Shallow Water

Blackout Hypoxia upon ascent from

depth

O2 partial pressure in lungs under pressure at bottom of a deep free-dive adequate to support consciousness at that depth

O2 levels drop below blackout threshold as the water pressure decreases upon ascent forcing gases out of bloodstream (Henry’s law)

Divers often hyperventilate prior to swimming or diving

Urge to exhale triggered by rising blood CO2 levels

Hyperventilation depletes CO2 leaving diver susceptible to sudden loss of consciousness from hypoxia

There is no bodily sensation that warns a diver of an impending blackout & divers victims lose consciousness & drown without alerting anyone they are in distress

Typically found on ocean floor

Blackout “Zones”

Diving Emergencies: AssessmentAscent rate

Diver experience

Depth gauge function

PMH including prior diving illness

Prescribed / illicit meds (i.e. ETOH)

Diving Emergencies: AssessmentTime of onset

Breathing apparatus used

Hypothermia-protective garment type worn

Aircraft travel following dive

Dive “Table” Parameter # dives, depth, & duration

US Navy / PADI Dive TablesDepth Time35 31040 20050 10060 6070 5080 4090 30100 25110 20115 15 120 13 130 10

Decompression Illness

Dives >33 ft, or shallow depth if (+) PMH

Nitrogen gas coming out of solution Symptoms between 5 mins-8

hrs post surfacing

Clinical Manifestations: MS: joint pain, parasthesias

lymphedema Neuro: seizure, HA, AMS,

paralysis, fatigue GI: abdominal pain, N/V Skin: pruritis Vasomotor: hypotension,

tachycardia

Management: Slow, controlled hyperbaric

chamber recompression

Decompression Illness TreatmentABCs & resuscitation as needed

Supportive careHyperbaric chamber

recompression If air evacuated, maintain cabin

pressure at sea level or fly at low altitude

Send diving equipment for analysis

Full cardiac & neurological work-up necessary to evaluate for underlying cause(s)

BarotraumaMask SqueezeTM rupture Middle ear squeezeBarosinusitis /

Barodentalgia VertigoSuit squeezeGI barotraumaMediastinal

emphysemaPneumothorax /

Hemothorax

Arterial Gas EmbolismSevere form of barotrauma

Onset of symptoms immediately upon ascent CVA, MI, cardiac arrest, LOC,

seizure, HA Suspect in patient with

neurological deficits immediately after ascent

Pressure induced gas transfer across alveolar-capillary membrane causes bubbles to enter arterial circulation

Treatment is hyperbaric chamber & resuscitation

Arterial Gas Embolism Can Occur in Brain, Lungs,

Heart, Joints, Skin

Arterial Gas Embolism TreatmentABCs, IV, Monitor

Airway managementResuscitation as needed

Supine position or reverse Tradeleburg

Frequent vital signs

Corticosteroids?

Rapid transport to a recompression chamber

Pulmonary OverpressureFailure to exhale during ascent

Can occur with dives in <6 ft of water

Lung rupture leaks air into pleural space compressing lung & aorta

SSX: Bloody sputum Chest pain Reduced chest movement Respiratory distress

Treat as a pneumothorax

Pneumomediastinum

Failure to exhale during ascent

Lung rupture forces air into neck, mediastinum, around heart & other organs

Symptoms Bloody sputum / dyspnea Chest pain Arrythmia Hypotension with narrow

pulse pressure Neck swelling, difficulty

swallowing, hoarse voice

Chest wall feels like “rice krispies”

Nitrogen Narcosis

Occurs during diveSigns and Symptoms

AMSImpaired judgment may

lead to further injury

TreatmentReturn to shallow depthHyperbaricsUse O2/helium mix during

dive (heliox)

Diving Emergencies

Patients generally triaged to local hospital for initial stabilization, then transferred to hyperbaric-capable facility

Diver’s Alert NetworkConsultation & referrals

24/7(919) 684-8111 Dan the Diving Dog

ReferencesNFPA 1670DAN Networkwww.uptodate.comWikipedia, GoogleBuzzacott P. Epidemiology

of injury in scuba diving. Med Sport Sci. 2012

Salahuddin M. SCUBA medicine: a first-responder's guide to diving injuries. Curr Sports Med Rep. 2011

Summaryprehospitalmd@gmail.com / www.TEAEMS.com

Diving physics review

Assessment & management of diving injuries

Treatment involves ABCs, stabilization & symptomatic management, & often resuscitation followed by a dive in a hyperbaric chamber