Dive TravelDive TravelDive TravelDive Travel

Edmond Kay MDEdmond Kay MDEdmond Kay MDEdmond Kay MD

Acknowledgements Acknowledgements Acknowledgements Acknowledgements

Dr Richard Moon, Dr Richard Moon, Divers Alert NetworkDivers Alert Network

Jack Connick, Jack Connick, Optical OceanOptical Ocean

Dr Richard Moon, Dr Richard Moon, Divers Alert NetworkDivers Alert Network

Jack Connick, Jack Connick, Optical OceanOptical Ocean

DeclarationsDeclarationsDeclarationsDeclarations

TopicsTopicsTopicsTopics

Before travelingBefore traveling- fitness issuesfitness issues- medicationmedication

While travelingWhile traveling- DAN dive & travel insuranceDAN dive & travel insurance- region specific precautionsregion specific precautions

Unwanted souvenirsUnwanted souvenirs- nastiesnasties

Bubble troubleBubble trouble- decompression illnessdecompression illness

Before travelingBefore traveling- fitness issuesfitness issues- medicationmedication

While travelingWhile traveling- DAN dive & travel insuranceDAN dive & travel insurance- region specific precautionsregion specific precautions

Unwanted souvenirsUnwanted souvenirs- nastiesnasties

Bubble troubleBubble trouble- decompression illnessdecompression illness

Gravity & MomentumGravity & MomentumGravity & MomentumGravity & Momentum

Pressure & ImmersionPressure & ImmersionPressure & ImmersionPressure & Immersion

Boyles Law Boyles Law Boyles Law Boyles Law

Pressure and Volume - Inversely ProportionalPressure and Volume - Inversely ProportionalPressure and Volume - Inversely ProportionalPressure and Volume - Inversely Proportional

Henry’s LawHenry’s LawHenry’s LawHenry’s Law

Amount of gas dissolved in a liquidAmount of gas dissolved in a liquiddirectly proportional to the partial pressuredirectly proportional to the partial pressure

of that gasof that gas

Amount of gas dissolved in a liquidAmount of gas dissolved in a liquiddirectly proportional to the partial pressuredirectly proportional to the partial pressure

of that gasof that gas

On surfaceOn surface

On decentOn decent

At pressureAt pressure

0

200

400

600

800

1000

1200

1400

1970

1972

1974

1976

1978

1980

1982

1984

1986

1988

1990

1992

1994

1996

Accidents

Deaths

Divers Alert Network, 1998Divers Alert Network, 1998

NN

Recreational Diving:Recreational Diving: DCS and Death DCS and Death

Recreational Diving:Recreational Diving: DCS and Death DCS and Death

What kind of DivingWhat kind of DivingWhat kind of DivingWhat kind of Diving

““Fitness to dive should apply only to the type of Fitness to dive should apply only to the type of diving in which the diver plans to engage”diving in which the diver plans to engage” - David Elliott, MD, OBE - David Elliott, MD, OBE

Moon REMoon RE

What kind of DiverWhat kind of DiverWhat kind of DiverWhat kind of Diver

Not fit right nowNot fit right now - dehydration, fatigue, URI, pregnancy- dehydration, fatigue, URI, pregnancy

Not fit withoutNot fit withoutspecial trainingspecial training

ADAADA - accommodation - accommodation - supervision - supervision

Adapted from Moon REAdapted from Moon RE

Fitness to DiveFitness to DiveFitness to DiveFitness to Dive

Able to do the “work”Able to do the “work”: : breathe, swim, exercisebreathe, swim, exercise Not susceptible to barotrauma:Not susceptible to barotrauma: ear, lung, GIear, lung, GI Not susceptible to loss of consciousness (drowning): Not susceptible to loss of consciousness (drowning):

convulsions, insulin dependent diabetes, heart blockconvulsions, insulin dependent diabetes, heart block Not pregnantNot pregnant

No diseases that diving could make worse:No diseases that diving could make worse: sinus or sinus or middle ear disease, previous labyrinthine window middle ear disease, previous labyrinthine window rupture, heart failurerupture, heart failure

Not ‘overly’ susceptible to DCINot ‘overly’ susceptible to DCIAge?Age? Female gender?Female gender?Obesity?Obesity? Menses?Menses?Previous decompression illness?Previous decompression illness? Fatigue, dehydration?Fatigue, dehydration?Orthopedic injuries or surgery?Orthopedic injuries or surgery? Atrial septal defects, PFO?Atrial septal defects, PFO?

Moon REMoon RE

Psychological & Behavioral Psychological & Behavioral Fitness?Fitness?

Psychological & Behavioral Psychological & Behavioral Fitness?Fitness?

Able to exercise good judgmentAble to exercise good judgment Not susceptible to disabling anxietyNot susceptible to disabling anxiety No sedating drugsNo sedating drugs

- alcohol & tranquilizers - alcohol & tranquilizers ADHDADHD

- oppositional & defiant- oppositional & defiant Psychosis, ManiaPsychosis, Mania

Able to exercise good judgmentAble to exercise good judgment Not susceptible to disabling anxietyNot susceptible to disabling anxiety No sedating drugsNo sedating drugs

- alcohol & tranquilizers - alcohol & tranquilizers ADHDADHD

- oppositional & defiant- oppositional & defiant Psychosis, ManiaPsychosis, Mania

Class of Drugs Drug Effects Adverse to Diving

Anticoagulants Hemorrhage from Barotrauma or Spinal DCS

Narcotics, Marijuana & Alcohol

Impaired judgment & problem solving. Aggravation of nitrogen narcosis

Tranquillizers Impaired judgment & problem solving. Aggravation of nitrogen narcosis

Anti-depressants Risk of seizures with Bupropion (Wellbutrin)

Decongestants & Antihistamines

Sleepiness & nasal rebound congestion. Risk of ear barotrauma and O2 Toxicity with pseudoephedrine (Sudafed)

Motion sickness drugs

Sedation, impaired judgment and aggravation of nitrogen narcosis.

Beta blockersReduced ability to respond to needs of stress. Aggravate Raynaud's Phenomenon and asthma

Anti - malarialsMefloquine (Lariam) psychological & neurological side effects are similar to symptoms of DCS. Doxycycline causes disabling photosensitivity.

Sympathomimetics

Amphetamines, methylphenidate and to a lesser extent pseudoephedrine (CNS stimulants) increase risk of CNS oxygen toxicity. Amphetamines can distort or amplify self-confidence (grandiosity) or increase risk of panic during frightening narcosis

How to Determine Fitness to DiveHow to Determine Fitness to DiveHow to Determine Fitness to DiveHow to Determine Fitness to Dive

What incremental risk is acceptable?What incremental risk is acceptable? Where should the threshold for qualification Where should the threshold for qualification

be set?be set?

What incremental risk is acceptable?What incremental risk is acceptable? Where should the threshold for qualification Where should the threshold for qualification

be set?be set?

““If you don’t have gills, the term ‘fitness to dive’ is a misnomer”If you don’t have gills, the term ‘fitness to dive’ is a misnomer” - Andy Veale MD- Andy Veale MD

"It's probably more important to ask if someone has ever run "It's probably more important to ask if someone has ever run out of gas on the freeway than to ask about most medical out of gas on the freeway than to ask about most medical conditions” - Tom Neuman MDconditions” - Tom Neuman MD

Adapted from Moon REAdapted from Moon RE

BarotraumaBarotraumaBarotraumaBarotrauma

SqueezeSqueezeSqueezeSqueeze

MIDDLE EAR SQUEEZE

MIDDLE EAR OVERPRESSURE (REVERSE BLOCK)

EXTERNAL EAR SQUEEZE

SINUS SQUEEZE

SINUS OVER PRESSURE (REVERSE BLOCK)

TOOTH SQUEEZE (BARODONTALGIA)

BODY (SUIT) / FACE (MASK) SQUEEZE

STOMACH / INTESTINE

INNER EAR BAROTRAUMAS

PULMONARY OVER INFLATION SYNDROMES

MIDDLE EAR SQUEEZE

MIDDLE EAR OVERPRESSURE (REVERSE BLOCK)

EXTERNAL EAR SQUEEZE

SINUS SQUEEZE

SINUS OVER PRESSURE (REVERSE BLOCK)

TOOTH SQUEEZE (BARODONTALGIA)

BODY (SUIT) / FACE (MASK) SQUEEZE

STOMACH / INTESTINE

INNER EAR BAROTRAUMAS

PULMONARY OVER INFLATION SYNDROMES

Sinus BarotraumaSinus BarotraumaSinus BarotraumaSinus Barotrauma

PreventablePreventablePreventablePreventable

Ear Barotrauma Ear Barotrauma Ear Barotrauma Ear Barotrauma

Most frequent Most frequent diving injurydiving injury Common in novice diversCommon in novice divers Poor understanding ofPoor understanding of

equalization techniques equalization techniques Middle Ear Barotrauma is…Middle Ear Barotrauma is…

Most frequent Most frequent diving injurydiving injury Common in novice diversCommon in novice divers Poor understanding ofPoor understanding of

equalization techniques equalization techniques Middle Ear Barotrauma is…Middle Ear Barotrauma is…

What is “Ear Fear”?What is “Ear Fear”?What is “Ear Fear”?What is “Ear Fear”?

Pressure perceived as Pressure perceived as “uncomfortable”“uncomfortable” Childhood pain Childhood pain adult fear adult fear Retrograde tear duct inflationRetrograde tear duct inflation Confusion over instructionsConfusion over instructions

Pressure perceived as Pressure perceived as “uncomfortable”“uncomfortable” Childhood pain Childhood pain adult fear adult fear Retrograde tear duct inflationRetrograde tear duct inflation Confusion over instructionsConfusion over instructions

Assessing Valsalva EffectivenessAssessing Valsalva EffectivenessAssessing Valsalva EffectivenessAssessing Valsalva Effectiveness

Watch The Nose Inflate!Watch The Nose Inflate! Fingers low on noseFingers low on nose Palpate firmness of inflationPalpate firmness of inflation

and compare it to your own and compare it to your own pressurization effortpressurization effort

Watch the Watch the pars flaccida pars flaccida of the of the Tympanic Membrane balloon out,Tympanic Membrane balloon out,““like a sail catching the wind”like a sail catching the wind”

Watch The Nose Inflate!Watch The Nose Inflate! Fingers low on noseFingers low on nose Palpate firmness of inflationPalpate firmness of inflation

and compare it to your own and compare it to your own pressurization effortpressurization effort

Watch the Watch the pars flaccida pars flaccida of the of the Tympanic Membrane balloon out,Tympanic Membrane balloon out,““like a sail catching the wind”like a sail catching the wind”

Normal EarNormal EarNormal EarNormal Ear

HemotympanumHemotympanumHemotympanumHemotympanum

Video OtoscopyVideo OtoscopyVideo OtoscopyVideo Otoscopy

divingdoc.comdivingdoc.comdivingdoc.comdivingdoc.com

Ear Clearing TechniquesEar Clearing TechniquesEar Clearing TechniquesEar Clearing Techniques

Valsalva Maneuver (1704)Valsalva Maneuver (1704) Frenzel Maneuver (1932)Frenzel Maneuver (1932)

throat pistonthroat piston BTV (Voluntary Tubal Opening)BTV (Voluntary Tubal Opening)

distilled yawndistilled yawn Lowry Technique (combinations)Lowry Technique (combinations)

pressurize and swallowpressurize and swallow pressurize and yawnpressurize and yawn

Valsalva Maneuver (1704)Valsalva Maneuver (1704) Frenzel Maneuver (1932)Frenzel Maneuver (1932)

throat pistonthroat piston BTV (Voluntary Tubal Opening)BTV (Voluntary Tubal Opening)

distilled yawndistilled yawn Lowry Technique (combinations)Lowry Technique (combinations)

pressurize and swallowpressurize and swallow pressurize and yawnpressurize and yawn

Pulmonary IssuesPulmonary IssuesPulmonary IssuesPulmonary Issues

Air FlowAir Flow Air TrappingAir Trapping

Air FlowAir Flow Air TrappingAir Trapping

Maximum Voluntary VentilationMaximum Voluntary Ventilationvs.vs.

Gas DensityGas Density

Maximum Voluntary VentilationMaximum Voluntary Ventilationvs.vs.

Gas DensityGas Density

00

2525

5050

7575

100100

00 5050 100100 150150 200200

Depth (fsw)Depth (fsw)

MVV MVV (fraction of 1 ATA)(fraction of 1 ATA)

Adapted from Moon REAdapted from Moon RE

CXR - 1 view or 2?CXR - 1 view or 2?CXR - 1 view or 2?CXR - 1 view or 2?

Bleb visible – Lat onlyBleb visible – Lat onlyBleb visible – Lat onlyBleb visible – Lat only

CT viewCT viewCT viewCT view

Chest CT after PBT in DiversChest CT after PBT in DiversChest CT after PBT in DiversChest CT after PBT in Divers

Reuter et al. Reuter et al. Br J RadiolBr J Radiol 70:440, 1997 70:440, 1997

0

5

10

N

Bulla/cystScarringInfiltrate/atelectasisNormal

AGEAGE PneumomediastinumPneumomediastinum

Unrestricted Clearance ?Unrestricted Clearance ?Unrestricted Clearance ?Unrestricted Clearance ?

Normal exercise toleranceNormal exercise tolerance Normal PFTNormal PFT

Forced vital capacity (FVC)Forced vital capacity (FVC) Forced expiratory volume in 1 second (FEV)Forced expiratory volume in 1 second (FEV)11

No significant reversible obstructionNo significant reversible obstruction Improvement < 12% (BD)Improvement < 12% (BD) Change not greater than 200 cc (BD)Change not greater than 200 cc (BD)

Normal exercise toleranceNormal exercise tolerance Normal PFTNormal PFT

Forced vital capacity (FVC)Forced vital capacity (FVC) Forced expiratory volume in 1 second (FEV)Forced expiratory volume in 1 second (FEV)11

No significant reversible obstructionNo significant reversible obstruction Improvement < 12% (BD)Improvement < 12% (BD) Change not greater than 200 cc (BD)Change not greater than 200 cc (BD)

Moon REMoon RE

Diving and AsthmaDiving and AsthmaDiving and AsthmaDiving and Asthma

No symptoms attributable to asthmaNo symptoms attributable to asthma

Normal physical examNormal physical exam

Normal spirometry before and after exercise Normal spirometry before and after exercise provocative test with or without medicationprovocative test with or without medication

Recommendations for Diving with AsthmaRecommendations for Diving with AsthmaRecommendations for Diving with AsthmaRecommendations for Diving with Asthma

Elliott (Ed). Are Asthmatics Fit to Dive? UHMS, 1996Elliott (Ed). Are Asthmatics Fit to Dive? UHMS, 1996

Seizure RiskSeizure RiskSeizure RiskSeizure Risk

Seizures underwater are likely to be fatalSeizures underwater are likely to be fatal

It is possible that the physiological It is possible that the physiological conditions during diving (hyperoxia, conditions during diving (hyperoxia, hypercapnia, immersion) could lower the hypercapnia, immersion) could lower the seizure thresholdseizure threshold

People with recurrent seizures should People with recurrent seizures should not divenot dive

Moon REMoon RE

SeizureSeizureSeizureSeizure

50% of adults with new onset seizures, 50% of adults with new onset seizures, normal neurological exam and brain normal neurological exam and brain imaging will have another seizureimaging will have another seizure

Risk increased with family history, Risk increased with family history, abnormal EEG, previous head injuryabnormal EEG, previous head injury

14 years after a first seizure the risk of a 14 years after a first seizure the risk of a second one is several fold greater than in second one is several fold greater than in the general populationthe general population

Coronary Artery DiseaseCoronary Artery DiseaseCoronary Artery DiseaseCoronary Artery Disease

Recreational Diving Fatalities USARecreational Diving Fatalities USARecreational Diving Fatalities USARecreational Diving Fatalities USA

0

5

10

15

20

25

30

35

40

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70

Age (years)

An

nu

al F

ata

lity

Ra

te p

er

10

0,0

00

Male

Female

Moon REMoon RE

Cause of DeathCause of DeathCause of DeathCause of Death

33%

62%

88%

93% 96%98% 100%

0

50

100

150

200

Drowning AGE Cardiac Trauma DCS LOC InappropriateGas

Fre

qu

en

cy

of

CO

D

0%

20%

40%

60%

80%

100%

Cu

mu

lati

ve

CO

D

33%

62%

88%

93% 96%98% 100%

0

50

100

150

200

Drowning AGE Cardiac Trauma DCS LOC InappropriateGas

Fre

qu

en

cy

of

CO

D

0%

20%

40%

60%

80%

100%

Cu

mu

lati

ve

CO

D

Denoble PJ, Caruso J, Dear G de L, Pieper CF, Vann RD, 2007Denoble PJ, Caruso J, Dear G de L, Pieper CF, Vann RD, 2007

Redistribution of Blood During ImmersionRedistribution of Blood During ImmersionRedistribution of Blood During ImmersionRedistribution of Blood During Immersion

Heart FailureHeart FailureHeart FailureHeart Failure

Immersion causes a displacement of 500-Immersion causes a displacement of 500-800 ml of blood from the legs into the thorax. 800 ml of blood from the legs into the thorax. This is even greater during cold water This is even greater during cold water immersionimmersion

If the patient’s ventricle is unlikely to tolerate If the patient’s ventricle is unlikely to tolerate a sudden 500 – 800 ml transfusion, diving a sudden 500 – 800 ml transfusion, diving (swimming?) should be restricted(swimming?) should be restricted

Moon REMoon RE

Coronary Artery DiseaseCoronary Artery DiseaseCoronary Artery DiseaseCoronary Artery Disease Patients with coronary artery disease are at Patients with coronary artery disease are at

risk of myocardial infarction and sudden risk of myocardial infarction and sudden death (60%)death (60%)

Cardiac work is related to contractility, heart Cardiac work is related to contractility, heart rate, afterload and preload. Preload is rate, afterload and preload. Preload is higher during immersion than in the dryhigher during immersion than in the dry

No diving if CAD. If patient has risk factors No diving if CAD. If patient has risk factors for CAD, rule out with exercise test (13 for CAD, rule out with exercise test (13 METS)METS)

Moon REMoon RE

Effect of Head and Torso Water Temperature Effect of Head and Torso Water Temperature on Hemodynamicson Hemodynamics

Effect of Head and Torso Water Temperature Effect of Head and Torso Water Temperature on Hemodynamicson Hemodynamics

Wester TE, et al. Wester TE, et al. J Appl PhysiolJ Appl Physiol 106: 691, 2009 106: 691, 2009

Fitness to Dive: ObesityFitness to Dive: Obesity- 2004 Diving Report- 2004 Diving Report

Fitness to Dive: ObesityFitness to Dive: Obesity- 2004 Diving Report- 2004 Diving Report

NIH Definitions Based on BMINIH Definitions Based on BMI

0

10

20

30

40

50

60

Underweight Normal Overweight Obese

% o

f Pop

ulat

ion

FatalityInjuryPDE

Moon REMoon RE

Stings & PuncturesStings & PuncturesStings & PuncturesStings & Punctures

OUCH!OUCH!OUCH!OUCH!

Jellyfish Jellyfish PrecautionsPrecautions

Jellyfish Jellyfish PrecautionsPrecautions

Irukandji SyndromeIrukandji SyndromeIrukandji SyndromeIrukandji Syndrome

One of the most venomous jellyfishOne of the most venomous jellyfish Severe headache, backache, muscle pains, Severe headache, backache, muscle pains,

chest and abdominal pain, nausea and chest and abdominal pain, nausea and vomiting, sweating, hypertensionvomiting, sweating, hypertension

EXTREMELY painfulEXTREMELY painful"rip your skin off""rip your skin off"

One of the most venomous jellyfishOne of the most venomous jellyfish Severe headache, backache, muscle pains, Severe headache, backache, muscle pains,

chest and abdominal pain, nausea and chest and abdominal pain, nausea and vomiting, sweating, hypertensionvomiting, sweating, hypertension

EXTREMELY painfulEXTREMELY painful"rip your skin off""rip your skin off"

Bubble TroubleBubble TroubleBubble TroubleBubble Trouble

Decompression SicknessDecompression Sickness

Arterial Gas EmbolismArterial Gas Embolism

The BendsThe BendsThe BendsThe Bends

DCSDCSDCSDCS

The condition caused by inert nitrogen gas The condition caused by inert nitrogen gas coming out of solution within the bodycoming out of solution within the body

In spite of more than a century of In spite of more than a century of investigation, the mechanisms underlying the investigation, the mechanisms underlying the various forms of DCS are far from clear various forms of DCS are far from clear

The condition caused by inert nitrogen gas The condition caused by inert nitrogen gas coming out of solution within the bodycoming out of solution within the body

In spite of more than a century of In spite of more than a century of investigation, the mechanisms underlying the investigation, the mechanisms underlying the various forms of DCS are far from clear various forms of DCS are far from clear

VENOUS BUBBLEVENOUS BUBBLEHypothesisHypothesiscirca 1980’scirca 1980’s

VENOUS BUBBLEVENOUS BUBBLEHypothesisHypothesiscirca 1980’scirca 1980’s

Mechanisms of DCSMechanisms of DCSMechanisms of DCSMechanisms of DCS

Bubble vascular occasionBubble vascular occasion - mechanical disruption- mechanical disruption

Endothelial injuryEndothelial injury - leukocyte adhesion, plasma loss- leukocyte adhesion, plasma loss

Tissue anoxiaTissue anoxia Reperfusion injuryReperfusion injury

- excitatory neurotransmitters- excitatory neurotransmitters - oxygen free radical damage- oxygen free radical damage

ApoptosisApoptosis - programmed cell death- programmed cell death

Bubble vascular occasionBubble vascular occasion - mechanical disruption- mechanical disruption

Endothelial injuryEndothelial injury - leukocyte adhesion, plasma loss- leukocyte adhesion, plasma loss

Tissue anoxiaTissue anoxia Reperfusion injuryReperfusion injury

- excitatory neurotransmitters- excitatory neurotransmitters - oxygen free radical damage- oxygen free radical damage

ApoptosisApoptosis - programmed cell death- programmed cell death

Dive PlanDive Plan(mathematical precision?)(mathematical precision?)

Dive PlanDive Plan(mathematical precision?)(mathematical precision?)

DCS symptom onsetDCS symptom onsetDCS symptom onsetDCS symptom onset

Time after dive Manifestations of DCS

1 hr 42%

3 hrs 60%

8 hrs 83%

24 hrs 98%

36 hrs 100%

DCS NomenclatureDCS NomenclatureDCS NomenclatureDCS Nomenclature

Compressed Air Work 1960’sCompressed Air Work 1960’s Diving and Aerospace 1970’sDiving and Aerospace 1970’s

Type 1 (simple DCS)Type 1 (simple DCS) Type 2 (serious DCS)Type 2 (serious DCS)

DCI DCI manifestationsmanifestations 1980’s 1980’s

mild, moderate or severemild, moderate or severe

Compressed Air Work 1960’sCompressed Air Work 1960’s Diving and Aerospace 1970’sDiving and Aerospace 1970’s

Type 1 (simple DCS)Type 1 (simple DCS) Type 2 (serious DCS)Type 2 (serious DCS)

DCI DCI manifestationsmanifestations 1980’s 1980’s

mild, moderate or severemild, moderate or severe

Symptom Cluster AnalysisSymptom Cluster Analysis1929 CASES OF DCS1929 CASES OF DCS

Symptom Cluster AnalysisSymptom Cluster Analysis1929 CASES OF DCS1929 CASES OF DCS

Ozyigit T, Egi S, Denoble P, Balestra C, AydinS, Vann R, Marroni A. Galatasaray University, Istanbul. Divers Alert Network. Haute EcolePaul Henri Spaak, Brussels, Istanbul University, Hyperbaric Center, Duke University, Durham NC

0

5

10

15

20

25

30

35

Live-Aboard Shore/Day-Boat Cozumel DiveProfessionals

Scapa Flow Cold-Water Wreck

DC

S C

ases

per

10,

000

Div

es

19,909 dives

5,090 dives

16,356 dives

5,139 divesMean =

4 DCS/103

dives

Absolute DCS RiskAbsolute DCS Risk - 1995-2002 PDE Data - 1995-2002 PDE Data

Absolute DCS RiskAbsolute DCS Risk - 1995-2002 PDE Data - 1995-2002 PDE Data

Vann RDVann RD