Terminal Objectives • Be familiar with the avoidance, recognition, and treatment of hypoxia/hyperventilation, aviation related trapped gas hazards, and decompression sickness.
Enabling Objectives 1.1 Define hypoxia/hyperventilation. 1.2 Recall four subjective/objective symptoms of hypoxia. 1.3 State the emergency procedures for a suspected case of hypoxia.
Enabling Objectives 1.4 State the NATOPS oxygen usage rules. 1.5 State three symptoms of hyperventilation. 1.6 State the emergency procedures for a suspected case of hyperventilation.
Enabling Objectives 1.7 Recall the causes, symptoms, and treatment of an inflight ear block, inflight sinus block, barodontalgia, and trapped intestinal gas. 1.8 Recall methods for avoiding an inflight ear block, inflight sinus block, inflight tooth pain, and trapped gas. 1.9 Define decompression sickness ( DCS) 1.10 State the situations where DCS is likely to occur.
Enabling Objectives 1.11 Distinguish between Type I and Type II DCS. 1.12 State the symptoms for Type I and Type II DCS. 1.13 State the NATOPS rules regarding scuba diving and flying. 1.14 State the emergency treatment for suspected DCS inflight.
AVIATION PHYSIOLOGY • HYPOXIA • HYPERVENTILATION • TRAPPED GAS • DECOMPRESSION SICKNESS
A Condition That Occurs When Insufficient Oxygen Is Supplied To Body Tissues
Causes Of Hypoxia • Cabin altitude >10K’ without O2 • Loss of cabin pressure (KC-130) • Anemia (A/C exhaust, blood donation, smoking, illness) • Chemical and Biological Warfare • Blood pooling due to prolonged sitting during long flights
TYPES OF HYPOXIA • ANEMIC • HISTOTOXIC • STAGNANT • HYPOXIC
ANEMIC HYPOXIA • Reduced oxygen carrying capacity of the blood... • TRAUMA • CARBON MONOXIDE • BLOOD DONATION
ANEMIC HYPOXIA • Types of toxic substances: • Aspirin • Nitrates • sulfanilamide's • Reductions due to conditions that effect red blood cell count: • Sickle cell anemia • Malnutrition • Sepsis
HISTOTOXIC HYPOXIA • Reduction in the ability of tissues to utilize oxygen... • ALCOHOL • DRUGS
Stagnant Hypoxia Pooling increases, vision begins to fade(gray-out). Blackout occurs due to a lack of blood to the brain. During prolonged mission flights blood may begin to pool in the extremities
Stagnant Hypoxia • Specific conditions: • Heart failure • Shock • Arterial spasm • Occlusion of blood vessels from tissue edema • Embolus • Thrombus • Plaques • Infarcts
18,000 ft Sea Level HYPOXIC HYPOXIA A REDUCED AMOUNT OF OXYGEN IN THE INSPIRED GASES …ALTITUDE
HYPOXIC HYPOXIA • Reduction of alveolar O2 tension • Interferes with gas exchange in two areas: • Ventilation • Diffusion Ventilation caused by: • Reduced barometric pressure • Laryngospasm • Severe asthma • Hypoventilation
HYPOXIC HYPOXIA • Reduction of alveolar O2 tension • Interferes with gas exchange in two areas: • Ventilation • Diffusion Diffusion caused by: • Pulmonary edema • pneumothorax • Pulmonary embolism • Embolism • Congenital heart defects
SUBJECTIVE SYMPTOMS • Tingling sensation • Dizziness • Fatigue • Air hunger • Euphoria • Hyperventilation
OBJECTIVE SYMPTOMS • Increased breathing rate • Cyanosis • Confusion • Loss of muscular coordination • Unconsciousness
HYPOXIA TREATMENT • OXYGEN 100% • CHECK EQUIPMENT • DESCEND • COMMUNICATE • CONTROL BREATHING
Excessive rate and/or depth of breathing resulting in reducedCO2 levels in the brain
CAUSES STRESS/ANXIEY HYPOXIA TREATMENT Same as Hypoxia SYPMTOMS Tingling Rapid Breathing Hot/Cold Flashes Visual Impairment Dizziness Muscle Spasms HYPERVENTILATION
TRAPPED GAS 43,000 feet • EARS • SINUSES • GASTRO-INTESTINAL • TEETH 25,000 feet 18,000 feet 10,000 feet Site level
EAR BLOCK • Causes • Symptoms • Treatment
Yawn Chew Swallow Descend Ear Block Treatment ( Ascent )
Ear Block Treatment ( Descent ) • Valsalva… • Yawn, Chew, Swallow • Slow descent rate • Post Flight Ear Block: • Caused by absorbsion of O2 within the middle ear • TREATMENT = Frequent Valsalva
FRONTALS ETHMOIDS SPHENOID MAXILLARY SINUS BLOCK • CAUSE • SYMPTOMS • TREATMENT
Sinus Block Treatment • Descend • Stop descent / Level Off • Valsalva • Slow descent
GI Tract Trapped Gas • Causes • Symptoms • Prevention / Treatment
Causes of GI Trapped Gas • Diet (food and drinks) • Illness
Trapped Gas Treatment • VENT • SLOW ASCENT RATE • DESCEND
Causes Symptoms Treatment Barodontalgia
Barodontalgia Treatment • DESCENT • PREVENTION: • “Avoid flying for 48-72 hours following major dental work”
Aviation DCS Evolved Nitrogen gas in the body often attributed to a decreased atmospheric pressure. - 18K’ Type I (Non-Serious) Bends Skin Manifestations Type II (Serious) Chokes CNS Multiple Symptoms DECOMPRESSION SICKNESS
FACTORS AFFECTING DCS • Scuba diving • Hydration level • Repeated exposures • Length of time at altitude • Rate of ascent • Altitude (18,000ft)
TREATMENT OF DCS • 100% OXYGEN (If Available) • DESCEND • IMMOBILIZE • SEEK QUALIFIED MEDICAL TREATMENT • RECOMPRESSION ?
SUMMARY • HYPOXIA • HYPERVENTILATION • TRAPPED GAS • DECOMPRESSION SICKNESS