CHT Physics & Gas Laws in Hyperbaric Medicine Flashcards
6 cards from real CHT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 CHT Physics & Gas Laws in Hyperbaric Medicine flashcards as text
Which gas law best explains why middle ear barotrauma occurs during hyperbaric chamber pressurization?
Answer: Boyle's Law
Boyle's Law explains that trapped gas in the middle ear decreases in volume as pressure increases, creating a pressure differential that causes barotrauma if not equalized.
The 'oxygen window' in hyperbaric therapy refers to:
Answer: The partial pressure gradient that facilitates inert gas (nitrogen) elimination from tissues
The oxygen window is the pressure differential created when tissues consume oxygen, replacing it with a gas-free space that accelerates nitrogen elimination without bubble formation.
Graham's Law of Diffusion states that lighter gases (lower molecular weight) diffuse:
Answer: Faster than heavier gases
Graham's Law states diffusion rate is inversely proportional to the square root of molecular weight, so lighter gases like helium diffuse faster than heavier gases like nitrogen.
At 3 ATA breathing air (21% O2, 79% N2), the partial pressure of nitrogen is approximately:
Answer: 1800 mmHg
At 3 ATA, total pressure = 3 × 760 = 2280 mmHg; nitrogen partial pressure = 0.79 × 2280 ≈ 1800 mmHg.
Charles's Law describes the relationship between gas volume and:
Answer: Temperature at constant pressure
Charles's Law states that at constant pressure, the volume of a gas is directly proportional to its absolute temperature.
The partial pressure of oxygen (PO2) at which CNS oxygen toxicity risk significantly increases is above:
Answer: 1.6 ATA
CNS oxygen toxicity risk increases significantly when PO2 exceeds 1.6 ATA, which is why most therapeutic HBOT protocols are designed to stay at or below this threshold.