Certified Hyperbaric Technologist Test CHT Hyperbaric Pharmacology 3

Question 1

When a patient is receiving HBO for a gas-forming infection, which antibiotic class works synergistically with HBO against Clostridium species?

Accepted Answer

Penicillins (e.g., ampicillin)

Answer

Fluoroquinolones (e.g., ciprofloxacin)

Answer

Macrolides (e.g., azithromycin)

Answer

Tetracyclines (e.g., doxycycline)

Question 2

A patient on metronidazole (Flagyl) is receiving HBO for necrotizing fasciitis. A key consideration is:

Accepted Answer

Metronidazole requires oxygen reduction to form toxic radicals, so HBO may reduce its effectiveness against anaerobes

Answer

Metronidazole is potentiated by hyperoxia and risk of toxicity increases

Answer

Metronidazole prevents CNS oxygen toxicity and is thus beneficial

Answer

No pharmacological interaction exists between metronidazole and HBO

Question 3

HBO's vasoconstriction effect is clinically useful in which situation?

Accepted Answer

Reducing edema in crush injuries and compartment syndrome

Answer

Controlling hemorrhage in surgical wounds

Answer

Lowering systemic blood pressure in hypertensive crisis

Answer

Preventing post-treatment hypotension

Question 4

Sildenafil (Viagra) and HBO are potentially problematic together because:

Accepted Answer

Both cause vasodilation and may produce significant hypotension

Answer

Sildenafil inhibits oxygen absorption at the cellular level

Answer

Both agents increase CNS seizure risk additively

Answer

Sildenafil prevents the angiogenic benefits of HBO

Question 5

In radiation-injured tissue, HBO promotes healing by:

Accepted Answer

Stimulating stem cell mobilization and angiogenesis in hypoxic tissue

Answer

Directly destroying residual radiation particles

Answer

Increasing radiation-damaged cell apoptosis to allow regrowth

Answer

Reducing fibrosis by compressing scar tissue under pressure

Question 6

What is the rationale for using HBO in cyanide poisoning?

Accepted Answer

HBO provides dissolved plasma oxygen that bypasses cytochrome oxidase inhibition by cyanide

Answer

HBO neutralizes cyanide by oxidizing it to cyanate at high pressure

Answer

HBO reverses CN binding to hemoglobin

Answer

HBO increases liver metabolism of cyanide compounds