Welcome to the
State of Alaska
Aeromedical Physician
Training Course
Course Objectives
Understanding of air physiology
 Describe patient management in the
aeromedical setting
 Recognize & anticipate problems
common in the aeromedical setting
 Dispatching considerations
 Sending and receiving considerations
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History of
Aeromedical Transports
International
USA
Alaska
The first Alaskan
Aeromedical Transport
Training Course 1980
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120 hours of classroom training
Focused on aircraft environment
Three part exam
Practical
Written
Oral
Federal Aviation Regulations
They govern all civil aviation operations:
FAR Part 91 (general operating flight rules)
FAR Part 135 (air taxi / commercial)
Violation may result in removal of certification
Effect of Altitude on Barometric Pressure
523 mm Hg
10, 000 feet
760 mm Hg
Sea Level
Earth
Boyles Law
The volume of a gas will varies
inversely with pressure, given the
temperature stays the same.
Aeromedical Considerations
Air splints
Air mattress, mast suit, etc.
Air in IV tubing drip chambers
Endotracheal tube cuffs?
Conditions in which barotrauma
may be dangerous:
Pneumothorax, Mediastinal, pericardial air
URI with sinusitis, otitis media, mastoiditis
Penetrating eye injury
Diaphragmatic hernia
Small bowel obstruction
Recent Surgery
Gas-filled abscess or cyst, Gas gangrene
Following scuba diving
Dalton’s Law
The total pressure of a gas mixture is the
sum of the individual partial pressures of
all the gases in a mixture.
Aeromedical Considerations
Pa02 decreases
Another Look at Dalton’s Law
10, 000 ft.
560 mm Hg
21% Partial Pressure of oxygen = 118
21% of 560 = 118
Sea Level
760 mm Hg
21% Partial Pressure of oxygen = 160
21% of 760 = 160
Charles’ Law
The volume of a gas will vary directly
with the absolute temperature, given
the mass and pressure stay the same.
Aeromedical Considerations
Gas filled medical equipment
increase size when warmed
Henry’s Law
The amount of gas dissolved in a solution
is directly proportional to the pressure of
the gas over the solution.
Aeromedical Considerations
Scuba Divers - Must fly sea level
Other Gas Laws
Other Gas Laws
Graham’s Law - rate of diffusion
Guy Lussac’s Law - pressure increase
Poiseulle’s Law - volume & pressure gradient
Altitude affects the
A-a GRADIENT
Definition
The difference in partial pressure of oxygen in
the alveolar gas spaces and the pressure in
the systemic arterial blood.
A-a Gradient = [(Barometric Pressure - 47)
times FIO2] - (PaCO2 /0.8) - PaO2
Pulm Physiology
A-a Gradient
What is the Aeromedical significance?
Sea level
760 mmHg - 47 = 713
(times the % of O2)
21% = 150
10,000 feet
560 mmHg - 47 = 513
(times the % of O2)
21% = 108
minus CO2 / Resp
quotient 50 mm Hg =
minus CO2 / Resp
quotient 50 mm Hg =
PaO2 100 (Predicted)
PaO2 58 (Predicted)
Four types of Hypoxia
Hypoxic hypoxia
Anemic hypoxia
Stagnant hypoxia
Histoxic hypoxia
Causes of
Hystoxic Hypoxia
Drugs
Prescriptive & recreational
Alcohol
one ounce = 2000 feet
Cigarettes
Three consecutive = 8000 feet
REVIEW -CELLULAR RESPIRATION
Cell Mitochondria
Protein, Fat, or
Glucose (C6 H12 O2)
2 Pyruvate
Acid
Electron Transport
Chain
ATP
Kreb Cycle
CO2
ATP
CO2
1/2 O2 + 2 Hydrogen
+ two electrons =
Makes Water
O2 function: discard electron waste after ATP synthesis
CO2: this is the cell waste product.
ELECTRON TRANSPORT CHAIN
Drugs, alcohol, & Smoking affect the Cytochrome
Fe.S Located in the Cell
FMN
Mitochondria
Fe.S
Cytochromes
Q
Cyt b
Fe.S
Cyt c1
Cyt c
Cyt a
Cytochrome, is a protein
with a heme group.
Cyt a3
1/2 O2
Factors affecting hypoxia:
Altitude
Rate of Ascent
Physical Fitness
Physical Activities
Drug & Medications
Individual Variations
Alcohol
Smoking
Plane Characteristics
There are basic physical features similar to
all planes.
Basic principles of flight similar in all planes:
center of gravity, lift, drag, & propulsion.
There are several physical characteristics
that individualize planes
Characteristics That Vary Among Planes
Pressurized?
Door dimensions
Passenger capability--including flight crew
Range
Cabin length and height
Cruise speed
Electrical requirements--is it available?
Runway consideration--length & surface type
Payload
Built in medical unit
Disadvantages of
Pressurized Aircraft
Potential for rapid decompression
(Typically commercial airlines fly at 30,000
to 36,000 feet. Cabin pressure typically
5,000 to 8,000).
More money : Plane and fuel
Requires a longer runway
Usually requires a paved runway
Disadvantages of
Unpressurized Aircraft
Air pressure fluctuates in:
Body cavities
Air filled tubes (i.e. Mast pants)
ET Tubes?
Increase patient discomfort
Altered effectiveness of medical equipment
Typical AK Medevac Aircraft
Cessna 185, 206 or 207
DeHavilland Beaver
DeHavilland Otter
Grumman Goose
Piper Cub
Piper Chieftan (Navajo)
Cessna Conquest
Boeing 737
Factors that Affect the
Decision to Transport
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Primary Principle--Do no further harm
Know indications for transfer
Transfer agreements
Transfer protocols
Stabilize patient
Transfer with skilled personnel and
adequate adjunctive equipment
Overview of the Process of
initiating a Medevac
1)
2)
3)
4)
5)
6)
7)
Planning
Inventory of resources & equipment
Medical control
Decision to transfer
Factors affecting transport
Communication -- Dispatch / Hospital
Communication -- Pilot
Planning Steps
Assess patient
Escorts available
Escorts level
Required equipment
Notification
Receiving community
Aircarrier
Family members
Types of Aircraft
Landing conditions
Number of patients
Condition of patients
Pre-Transport Records
Clinic or ambulance
Insurance info
Family contact number
Clinic / Medevac Personnel
Prepare, Practice, Educate
A
Successful
Medevac starts
before the patient gets ill.
Medical Control
Establish protocols, Educate
Dispatch / Pilot
Know what to anticipate
Pilot Weather Concerns
Icing
Turbulence
Wind direction & intensity for take-off
Weather at landing community
Extra fuel needed due to strong winds
The Pilot has the final word on weather.
Inventory Your
Community Resources
Airfields
Air carriers
Types of aircraft
Escort qualifications
Medical equipment available
Rescue vs Medevac
State of Alaska:
Resources Available for
Rescue Operations
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Alaska State Troopers
U.S. Coast Guard
MAST
Alaska Air National Guard
Local Army Guard
Decision to Transfer
Based on Matching:
PATIENT
Medevac
Aircraft
1) ALS or BLS
2) Critical Care
3) Specialty
Escort
Training level
Transport with Caution
Diving
Gas Gangrene
Pneumothorax
Hypoxia
Cardiac
Wired Jaw
Anemia
Recent Abdominal Surgery
Rural Physician
Medical Decision to Transfer
Decision is made based on
Weather
Plane availability
Staff availability and skill level
Type of patient (pediatric, OB)
Remember: The rural physician is taking
care of the patient with out the current
technological luxuries. Like CT scans, etc
Rural Physician
Medical Decision to Transfer
Conflicts arise when the “city” doctor
request you fix the problem. Not
understanding the diagnostic, staffing,
and equipment limitations of the rural
area.
Education of referring physician may be
necessary to avoid conflict.
Rural Physician
Medical Decision to Transfer
At times the patient stops at another
community due to weather restrictions.
This new health care person may alter your
initial plan of care. Communication is the
key to preventing a disaster.
Rural Physician
Medical Decision to Transfer
How long would you keep a patient in a
remote area with out
A surgeon
Advanced lab capabilities
CT scan
or Ultrasound
Knowing you only have two flights a week.
Rural Physician
Medical Decision to Transfer
Limitations in staff and supplies may force
medical triage decisions.
Triage
Salvageable vs the non-salvageable.
The sickest salvageable patient to town.
Rural Physician
Medical Decision to Transfer
Realize some people choose to stay in the
rural area AMA.
However, they may “change their mind”.
Now, you have a sick person and may not
have the supplies to take care of them.
Example: Pre-eclampsia at a doorstep
delivery.
Dispatch / Hospital
Dispatch
Never pressure the pilot into a flight.
Inform pilot if patient weight excessive or
sea-level cabin needed
Never, never, never, tell the pilot the patient
will die unless he flys
Hospital
Know names of contact people
Ask for patient follow-up
Aircraft Orientation: Prior to a flight
have the pilot discuss the following:
ELT (Not to be confused with a BLT)
Survival Gear
Fire Extinguisher
Flotation Devices
Emergency Exit Operation
Oxygen Storage
Equipment / Patient Tie Downs
Radio
Essential Communication
with the Pilot
Discuss
Air-ground radio communications
Flight maneuvers
(i.e. high G-force during take-off)
Altitude restrictions (prior to taking on fuel)
Cabin temperature considerations
Weight of the patient (esp. if excessive)
If electrical power available
Aeromedical Concerns
Gas expands
Hypoxia
Stresses of flight
Psychological status of patient & escort
Equipment
Available
Functioning
Secured
Aeromedical Considerations of
Eye and facial Injuries
Head (free air?)
Chest
Respiratory
Abdominal
Anemia / Sickle cell
Aeromedical Considerations of
Hypothermia and frostbite
Psychiatric emergencies
Maternal
Pediatric
Burns
Amputations
Effects of Altitude on PaO2 may
be Particularly Hazardous for:
Shock
Severe respiratory distress (ARDS, COPD)
Decompensated cardiac disease (CHF, MI)
Severe anemia (especially SS)
Glaucoma, eye injury, recent eye surgery
Cyanotic congenital heart disease
Epilepsy
CNS injury requiring 02
Things that will injure
or kill the patient:
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Illness
Trauma
Too much care
Too little care
Matching the Escort to Patient
Skill level of:
EMT I
EMT II
EMT III
Paramedic
Nurse
Critical Care Air-ambulance
Match escort to worst pt case scenario
You have a pt with a possible
Ruptured Appendix
Who do you use?
EMT I
EMT II
EMT III
Paramedic
Nurse
Critical Care Air-ambulance
Other Medical Escort &
Patient Considerations
Strength & fitness
Weight
Motion sickness
Pre-existing health problems
Upper respiratory infections
Matching escort to patient:
Determine the potential problems
escort could encounter should the
patient deteriorate.....
The escorts skill level and equipment
should match the WORST possible
patient problem.
Preflight & Postflight
check sheet
essential
Potential Adverse Effects of
Altitude on Escort
Reduced attention span
Impaired judgment
Develop “What, me worry?” attitude
Effects of drugs & fatigue are potentiated
Air sickness & claustrophobia
Decreased night vision, poor cabin lighting
Increased insensible water loss due to
decreased humidity
Stages of Flight
Enplaning
Don’t step on plane door step while holding pt
Take-off
Secure yourself, pt, & equipment
Descent & Deplaning
Respect the pilots “sterile zone”
Transfer of Care
Give report. Label all equipment.
“G” loading for various patient positions
A.
G force
B.
G force
C.
G force
D.
G force
Aircraft Moving Remember: “G” force higher on takeoff
Safety Considerations
Airstrip -- Airport
Securing Equipment
Securing Personnel
Take-off and Landing
Inflight Emergency
Plane & Helicopter
Safety
Safety: Take-off & Landing
Artificial light should not be used. If need
light--use a hand held flashlight with clear
red filter.
Respect the “sterile” field, do not talk to the
pilot if below 10,000 feet. (This is a FAA
regulation).
Don’t touch any cockpit controls unless the
pilot instructs you to do so.
Safety
Safety: Plane & Helicopter Safety
General:
Pilot is the final authority for continuing or
canceling a flight.
Helicopter specific:
Always secure loose items.
Never hold IV poles or arms above your head.
Stay lower than the person next to you.
Safety
Safety: Securing Equipment
and Personnel
All equipment will be secured for flight (FAA
Regulation 91.203
All personnel must be secured for take-off
and landing (FAA regulations 91.14,
paragraph 3)
Safety
Safety: Inflight Emergency
Know the location & operation of:
Exits
Fire extinguishers
Survival equipment
Flotation devices
Rapid Decompression procedure
Secure patient, equipment & yourself
Stay calm & do not disturb the pilot
Safety
Patient Problems in Flight
Turbulence
Positioning
Lighting
Motion Sickness
Prolonged Immobility
Disorientation
Unable to ausc lung sounds
Other Patient
Problems in Flight
Exercise
Oral Hygiene
Sleep
Elimination
Ear & Sinus Squeeze
Tooth Squeeze
Electrical Power
Do you have an in-plane power source?
Carry extra batteries.
Have equipment inspected on a routine basis.
Remember: There is a limit to the number
of cords you can plug into an outlet.
Equipment Affected by Altitude
Oxygen
To Calculate number of tanks:
Flight time plus two hours
E cylinder lasts 1 hour at 10L/min
Actual flow rate is greater than
indicated
Must be secured well
IV’s
Glass Bottles (Nitroglycerin bottles)
Vent & tape glass
Don’t hang above pt’s head
Plastic
Plastic preferred over glass when possible
Use pressure bag
Vent air prior to using pressure bag
Equipment Affected by Altitude
Cold Weather Considerations
Ambu: stiff plastic does NOT re-inflate well if it
gets cold
IV lines will freeze
Patient’s head needs to be covered
Battery life short
Medical equipment batteries
Plane batteries (Don’t leave a light on!)
Plastic may break (i.e. O2 rings)
Infection Control
Universal precautions
Cleaning equipment
Cleaning aircraft / vehicle
Discard of contaminated material
Seven Basic Survival Steps
1.
2.
3.
4.
5.
6.
7.
Recognition
Inventory
Shelter
Water
Signals
Food
Survival / Spiritual activity
Most Common Reasons for Failure to
Survive Emergencies Are:
• Wrong attitude
• Carelessness
• Lack of equipment
• Inability to use equipment
• Inability to adapt to environment
• No will to live
Safe Aeromedical patient care
starts by educating yourself
and staff.
Community Resources