Part 1 Flashcards
What is Boyle’s Law?
The pressure of a gas is inversely proportional to the volume of a gas at a constant temperature
P1V1 = P2V2. Affects ETT cuffs, MAST trousers, air splints, IV drip rates
What does Dalton’s Law state?
The total pressure of a gas mixture is the sum of the partial pressures of all the gases in the mixture
Pi = P1 + P2 + P3 + … + Pn. Responsible for soft tissue swelling at altitude.
What is Charles’ Law?
At a constant pressure, the volume of gas is directly proportional to the absolute temperature of the gas
V1 / T1 = V2 / T2. Example: Oxygen tank gets hot when charged.
Describe Gay-Lussac’s Law.
Directly proportional relationship between temperature and pressure
P1 / T1 = P2 / T2. Example: Oxygen cylinder pressure drops overnight.
What is Graham’s Law?
Law of Gaseous Diffusion
The rate of diffusion of a gas through a liquid medium is directly related to the solubility of the gas and inversely proportional to the square root of its density.
What does Henry’s Law explain?
The quantity of gas dissolved in a liquid is proportional to the partial pressure of the gas in contact with the liquid
Affects divers, can lead to decompression sickness ‘the bends’.
What is decompression sickness commonly known as?
‘The bends’
Related to Henry’s Law.
What are the symptoms of Type I decompression sickness?
Painful joints, mottled skin, pruritic symptoms
Nitrogen related, may feel like ‘ants crawling on the skin’.
What are the symptoms of Type II decompression sickness?
Neurologic signs, hypovolemic shock, pulmonary ‘chokes’
Symptoms include cough, hemoptysis, dyspnea.
What causes Arterial Gas Embolism (AGE)?
Breath holding during ascent on a dive
Causes air to enter blood vessels, leading to ischemia.
What is the pressure at sea level?
760 torr or mmHg (1 ATM)
Every 33 feet underwater = 1 ATM.
What is the physiological zone in altitude physiology?
Sea Level to 10,000 ft MSL
Night vision decreases beginning at 5,000 ft MSL.
What happens in the physiologically deficient zone?
10,000 to 50,000 ft MSL requires oxygen or pressurization to survive
Sudden decompression significantly reduces time of useful consciousness.
What is the oxygen adjustment calculation formula?
(FiO2 x P1) / P2 = FiO2 required for ascent
FiO2 = Fraction of inspired oxygen.
What is hypemic hypoxia?
Reduction in the O2 carrying capacity of blood
Causes include anemia and hemorrhage.
What are the stages of hypoxia?
- Indifferent
- Compensatory
- Disturbance
- Critical
Indifferent stage is most important because reasoning abilities are still intact.
What is the #1 cause of crashes in aviation?
Weather
#2 cause is night flight.
What is the significance of the sterile cockpit rule?
Only essential communication during critical phases of flight
Applies during takeoff, landing, refueling, and taxi.
What is the maximum duty day under FAR Part 135?
14 hours
Applies to flying passengers for money.
What is the role of AMRM?
Distributes workload and involves all members in mission planning
Also referred to as Crew Resource Management (CRM).
What are the weather minimums for flying in mountainous areas during the day?
1,000 ft - 3 miles
Applies to cross country flights.
What is required for a pilot in command of a helicopter?
2,000 hours total flight time, 1,200 hours in a helicopter
Must be instrument rated.
What is barodontalgia?
Tooth pain due to air trapped in fillings expanding on ascent
Also referred to as ‘Aerodontaligia’.
What is barotitis?
Ear pain due to air pressure changes during descent
Caused by Eustachian Tube Dysfunction.
