Hyperbaric Medicine Principles & Physiology Flashcards
7 cards from real CHS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Hyperbaric Medicine Principles & Physiology flashcards as text
Which of the following best describes the concept of 'critical closing pressure' in hyperbaric oxygen-induced vasoconstriction?
Answer: The minimum pressure needed to maintain vessel patency against tissue edema
Critical closing pressure is the transmural pressure below which vessels collapse; HBO2 vasoconstriction raises this threshold, helping reduce edema in swollen tissues.
In the context of hyperbaric medicine, what does the term 'on-gassing' refer to?
Answer: Inert gas uptake by tissues during pressurization or bottom time
On-gassing describes the uptake of inert gases (nitrogen or helium) into body tissues as partial pressure increases during descent or bottom time.
A patient with poorly controlled diabetes receives HBO2 therapy for a diabetic foot ulcer. Which metabolic effect of HBO2 should the treatment team monitor closely?
Answer: Hypoglycemia, as HBO2 enhances insulin sensitivity
HBO2 can enhance insulin sensitivity and glucose uptake, placing diabetic patients at risk for hypoglycemia, requiring blood glucose monitoring before and after treatments.
What is the P50 value of normal adult hemoglobin and what does it represent?
Answer: 26 mmHg; the PO2 at which hemoglobin is 50% saturated with oxygen
P50 is approximately 26 mmHg and represents the partial pressure of oxygen at which hemoglobin is half-saturated, reflecting hemoglobin's oxygen affinity.
Which treatment table is most commonly used for treating arterial gas embolism (AGE) in the United States?
Answer: US Navy Treatment Table 6
US Navy Treatment Table 6 is the standard first-line treatment for arterial gas embolism and serious decompression sickness, involving oxygen breathing at 2.8 ATA.
During hyperbaric oxygen therapy, what happens to cerebral blood flow (CBF)?
Answer: CBF decreases due to hyperoxygenation-induced cerebral vasoconstriction
High PaO2 during HBO2 causes cerebral vasoconstriction, reducing CBF by approximately 25%, which limits oxygen delivery to the brain but is offset by the high dissolved oxygen.
Which tissue type has the highest rate of inert gas uptake (fastest half-time) during hyperbaric exposure according to decompression theory?
Answer: Blood and fast tissues (e.g., lung)
Blood and highly perfused tissues have the fastest half-times for inert gas uptake, saturating quickly, while poorly perfused tissues like fat and tendons saturate much more slowly.