Otologic Manifestations of Barotrauma

David M. Kaylie, MD FACS

Otolaryngology – Head and Neck Surgery

ENT Manifestations of Barotrauma

• EAC squeeze

• Sinus squeeze

• Mask squeeze

• Middle Ear

Barotrauma

Elastic Cavity

• The pressure of a gas is inversely proportional to volume at constant temperature

• Boyle’s lawP1V1=P2V2

30 m

surface

10 m

1 atm

2 atm

4 atm

Inelastic Cavity

• Constant volume

• Pressure changes surface

33ft

1 atm

4 atm30 m

Cavities

33ft

1 atm

4 atm

132 ft

3 ATM

Lungs (elastic)

Bony Cavity (inelastic))

Surface

Changing Pressure

• 33 feet of seawater (fsw)=1 atmosphere pressure (14.7 psi)

• Balloon (or Lungs) at surface– If pressure is 3x, volume is 1/3 and density is

3x– When breathe at depth, gas at higher

pressure than surface– If hold breath as resurface

• Volume expands and lungs overinflate.

– DON’T HOLD BREATH

External Ear Canal Squeeze

• Hood

• Cerumen

• Plug

• Elderly

• Congenital small ear canals

• Swimmers (Surfers) Ear → Exostoses

Exostoses

• Cold water

exposure

• Benign

• Trap cerumen

Osteoma

External Ear Canal Barotrauma

Inside: Hemotympanum and Hemorrhage of Ear Canal Skin

1 Month: Exfoliation

6 Weeks: Otitis Externa

Treatment of EAC Barotrauma

• Dry ear precautions x 6 weeks (cotton/vas)

• Topical antibiotic/steroid drops (Ciprodex)

• Oral antibiotics if cellulitis (amox/clav)

• Wick if obstructed (merocel)

• Analgesia

Barosinusitis

• Descent 68%, Ascent 32% (Fagan 1976)

• Pain

• Nosebleed

Barosinusitis

• Frontal > maxillary > ethmoid

• Blindness and meningitis (Parell and Becker, 2000)

Treatment of Barosinusitis

• Elevate head

• Heat

• Oxymetazoline (Afrin)

• Pseudoephedrine (Sudafed)

• Avoid antihistamine – not beneficial

• Antibiotics for secondary bacterial infection

• Analgesia

Middle Ear Barotrauma

• Most common medical condition of divers– Occurs mainly on descent– Symptoms- pain, conductive hearing loss– Signs- hemotympanum, perforation

MEBT

• 4 fsw pressure > tensor tympani strength

• 10–69 fsw Dimeric TM rupture– Keller, 1958– Jensen, 1993

Normal Ear Canal and TM

Acute Hemotympanum

Resolving Hemotympanum

Perforation

Management of MEBT

• Usually resolves without treatment

• Oxymetazoline < 1 wk

• Antibiotics in advanced cases

• No diving until sx free, normal TM and able to autoinflate x 3 mo.

EqualizingGeneral Recommendations

• Avoid diving with URI, allergies

• Avoid medications causing

nasal congestion (turbinate ↑)• Antihypertensives• BPH (Hytrin)• ED (Viagra)

• Descent feet first

• Autoinflate 1-2 ft. No pain is acceptable

Equalizing Techniques

• Swallow, jaw thrust

• pseudoValsalva:– Alar balloon

• Lowry:– pValsalva+swallow

• Edmonds:– pValsalva+jaw thrust

Other Equalizing TechniquesCourtesy Allen Dekelboum, MD

• Toynbee:– Swallow with mouth and nose closed– Good for ascent

• Frenzel:– pValsalva with throat contraction

• Neck twitch:– Sudden lateral motion with nose closed

Equalizing Middle Ear:

Managing Difficult Cases

• Dry land practice

• Anchor line – helps control decompression stop in rough water

• Private lesson

• No bouncing

• Medication

Medication for Eustachian Tube Dysfunction

• Otolaryngology examination• Rarely: Allergy, Septum, CT or MRI• Topical nasal steroid• Afrin 12 hour

• Rebound

• Sudafed 120 mg ER• Cardiac, High blood pressure, Urinary retention

• Oral corticosteroids (prednisone, medrol)• Diabetes, Peptic ulcer, GERD, Infection, CNS, +++

TMJ

• 25 – 65% of SCUBA divers

• Sea Cure

• Right Bite

• Custom mouth piece

• Check hose length

Otolaryngology clearance to dive

• Normal examination, able to auto inflate• Diving with ENT disorders

– Meniere’s disease (1 year rule, asymmetrical C°)– Prior IEBT (hearing loss, vertigo)– S/P Surgery

• Tympanoplasty • Mastoidectomy (C°)• Ossiculoplasty• Stapedotomy (C°)• Cochlear Implant (C°)• Acoustic Neuroma• ESS• Laryngeal surgery

Meniere’s Disease• Spontaneous vertigo at depth

• Emphasize risk of aspiration, death

• One year symptom free without treatment chamber/rescue diver

• Simultaneous (C°)

Dive with perforation/cavity

• Pro Ear 2000

Dive with perforation

Dive with perforation/cavity

• Dry Hood

Diving After Ear Surgery• Tympanoplasty 3 months• PORP yes • TORP +/-• Cochlear Implant 3 atm (device 4 atm)• PLF +/-• Acoustic neuroma No

Dive after Sinus Surgery

• -6 weeks

• -Healed ostia

Practical Approach to Stings

• Hot water (as tolerated, 110°)

• Ammonia, alcohol, papain, peroxide

• Vibrio vulnificus – gram negative– Ceftriaxone, Cipro, Septra, Doxycycline

The Dizzy Diver

Differential

• Hangover• Motion sickness• Disembarkment• Diving disorders• Heart• Circulation• CNS, Endocrine

Motion Sickness

• Mechanism: sensory mismatch (adaptation)

– Yaw (0.2 Hz) vertical linear motion– Susceptibility: Ages: 2- 10; 40-50

• Non-pharmacologic therapy– Sea Band (P6, Nei Kuan point)

• = placebo • Some studies show it works

MEDICAL TREATMENT OF MOTION SICKNESS

• Pharmacologic therapy– Diminhydrinate (50-100mg) antihistamine 2hrs 8hrs

drowsy

– Meclizine (25 mg) antihistamine 2hrs 6hrs drowsy

– Promethazine (25-50mg) phenothiazine 2hrs 18hrdrowsy

– Scopolamine (0.5 mg) antimuscarinic 8hrs72hr drowsy anticholinergic

– D-amphetamine (5-10mg) amphetamine 1hr 6hr abuse, palpitation, HBP, arrhythmia, psychosis,

insomnia, euphoria, use in pregnancy, MAOI, hyperthyroid

Disembarkment Syndrome

(Mal de debarquement)

• Tal (2005)– Swaying, swinging, unsteadiness after return to land– Symptoms appear after landing– Associated with sea sickness while onboard– No objective measures available– Mostly women

• Hain (1999)– 26 of 27 women (age = 49.3)– Duration 3.5 years– Treatment

• Meclizine -• Scopolamine -• Vestibular rehab -• Benzodiazapines +

Diving Disorders Causing Dizziness

•Four categories of IEBT–During compression–At Stable Depths–During decompression–Noise trauma

Diving Disorders Causing Dizziness

•Inner ear barotrauma

•Perilymph fistula

•Inner ear DCI

•Alternobaric vertigo

•Gas toxicity

•Isobaric counter-diffusion

INNER EAR BAROTRAUMA (IEBT)

• Usually with MEBT

• Cochlear 90%, Vestibular 60%, Both 50% (Molvaer, 1988)

• Mechanism– Forced inflation on descent– Sudden equilibration – TM snaps, pressure wave from stapes to

RWM

Oval and Round Windows

• Sudden insufflation of middle ear snaps TM laterally, displacing stapes laterally and RW medially.

Incidence of IEBT

• 76 of 15,000 (0.5%) logged dives– Molvaer (1988)

• 26 of 319 (8%) patients with dive-ENT disorders– Klingmann (2006)

Recurrent IEBT

• Israel Naval Medical Institute– 2 of 44 (5%) of IEBT seen in 18 years (Shupak, 2006)

Treatment of IEBT

• Bed rest, head elevated

• Control B.P., discontinue aspirin

• Prednisone

• Observe (dial tone, etc.), serial audio

• Explore if strong suspicion of PLF

MECHANISM: - RWM or OW ligament - Implosion - Explosion

Rupture on descentSymptoms on ascent

gas from ME to IE (Molvaer, 1988)

PERILYMPH FISTULA

Perilymph Fistula

• Increased CSF pressure without equilibration = OW

• Sudden forced insufflation with snap of TM = OW or RW

PERILYMPH FISTULA

• Pneumolabyrinth

TREATMENT: 1. Bedrest, head elevated x 5d

2. Explore if SNHL progresses

3. Explore immediately if significant SNHL occurs with barotrauma

4. Explore vertigo > 5 days (normal MR and neuro)

PERILYMPH FISTULA

PERILYMPH FISTULA

Middle ear exploration• 30 minutes• Local or G.A.

PERILYMPH FISTULA

INNER EAR DECOMPRESSION ILLNESS

(IEDCI)• Any depth, any diver• More common in decompression

diving– Dives >130 feet require special gas

mixtures

INNER EAR DECOMPRESSION ILLNESS

(IEDCI)• Vertigo (most common), HL, tinnitus• Type II DCI

– Associated with systemic DCI: spinal cord symptoms, pain, itching, rash, dyspnea, LOC, death

– Inner ear: bubble formation → hemorrhage

tissue rupture (Antonelli, 1993)

Recurrent IEDCI

• 5 of 24 IEDCI (21%)• Nachum (2001)

• 2 of 18 IEDCI (11%)• Klingman (2006)

Management of IEDCI

• HBO, fluids, steroids, n-acetyl cysteine– HBO within 1 hr → 50% complete resolution (Nachum, 2001)– 5 hr → 10% (Shupak, 2003)– 10 hr → 22% (Klingmann, 2006)

• Do not dive for 3 months (Molvaer, 2003)– Do not dive if SNHL, RVR persist?

• Recompression with fistula safe– Guinea pigs (Stevens, 1991)– Human experience (Dekelboum 2005; Klingmann 2004)– Tubes

Right to Left Shunt (PFO)

• R/O PFO in patients with DCI– Right to left shunt in IEDCI 82%

• in controls 25% (Cantais, 2003; Klingmann, 2006)

– German Diving Medical Society—’Unfit to Dive’

ALTERNOBARIC VERTIGO

• Asymmetric ME pressure Onset during ascent

Duration up to 20 minutes(Lundgren, 1965)

• Human study: 20 mm Hg asym→NYS

(Henrickson, 1966)

Incidence of Alternobaric Vertigo

• 10% of Swedish divers (Lundgren, 1974)

• 33% of Norwegian divers (n = 194) (Molvaer, 1988)

• 14% sport divers (OME or ET) (Uzun, 2003)

ASYMMETRIC CALORIC STIMULATION

• Stimulus: – Unilateral EAC obstruction

(cerumen, plug, hood, squeeze)

– ME/Mastoid asymmetry

(bone, OME, squeeze)

• Response:– Compensated RVR

GAS TOXICITY

• Nitrogen narcosis (rapture)Dizziness, hallucination>100 feet

• O² toxicity: Seizure, deathVENTID (vision, ears, nausea,

twitching, irritaion, death

C0², CO contamination

COUNTERDIFFUSION

• Physiologic effect of diffusion of different gases in opposite directions under constant ambient pressure

• Two gases with different diffusion and solubility coefficients– Rapidly diffusing gas moves into tissues– More soluble gas diffuses slower

• Local supersaturation and bubbles• Occurs at perilymph/endolymph boundaries• Skin lesions and vertigo most common

Counterdiffusion

• Occurs in divers– Immersed in lighter rapidly diffusing gas

(helium)– Breathes slower gas (neon or nitrogen)

• Prevent by – Recompressing when switching from N to He

rich mixes (other way around ok)– Avoiding helium rich gases for breathing when

surrounded by nitrogen rich gases

DIFFERENTIAL DIAGNOSIS

DIAGNOSIS

IEBT + + DescentFistula + D/AIEDCI + AscentAsymmetric caloric - DescentAlternobaric vertigo - AscentGas toxicity - StableCounter diffusion +/- Stable

Hearing loss Onset