Certified Hyperbaric Technologist Test Hyperbaric Wound Healing 2 — Questions and Answers
Question 1: Which physiologic mechanism most directly explains how HBO2 therapy improves healing in a hypoxic wound?
- Increased dissolved oxygen in plasma driving diffusion into ischemic tissue (Correct answer)
- Reduced systemic blood pressure
- Direct antibiotic delivery to bacteria
- Stimulation of red blood cell agglutination
Correct answer: Increased dissolved oxygen in plasma driving diffusion into ischemic tissue
HBO2 dramatically raises plasma-dissolved oxygen, steepening the diffusion gradient into hypoxic tissue.
Question 2: A diabetic foot ulcer classified as Wagner grade 3 with osteomyelitis is generally considered:
- An approved indication for adjunctive HBO2 therapy (Correct answer)
- An absolute contraindication
- Unaffected by oxygen tension
- Treatable only with topical oxygen
Correct answer: An approved indication for adjunctive HBO2 therapy
Wagner grade 3 or higher diabetic foot ulcers are recognized indications for adjunctive HBO2.
Question 3: Hyperoxia during HBO2 promotes wound healing partly by stimulating which process essential for new tissue?
- Angiogenesis and fibroblast collagen synthesis (Correct answer)
- Lymphatic drainage shutdown
- Permanent vasodilation
- Inhibition of growth factors
Correct answer: Angiogenesis and fibroblast collagen synthesis
Elevated oxygen tension drives angiogenesis and supports collagen production by fibroblasts.
Question 4: Which assessment best predicts whether a wound is likely to respond to HBO2 therapy?
- Transcutaneous oximetry (TcPO2) measurements (Correct answer)
- Resting heart rate
- Patient body weight
- Ambient room temperature
Correct answer: Transcutaneous oximetry (TcPO2) measurements
TcPO2 measurements, especially in-chamber, help predict tissue oxygenation response.
Question 5: Why does HBO2 enhance leukocyte killing of bacteria in an infected wound?
- Oxygen-dependent respiratory burst requires adequate tissue O2 (Correct answer)
- It cools the tissue to slow bacteria
- It removes all moisture from the wound
- It blocks white cell migration
Correct answer: Oxygen-dependent respiratory burst requires adequate tissue O2
Neutrophil oxidative (respiratory) burst killing is oxygen-dependent and restored by raising tissue O2.
Question 6: A typical HBO2 wound-healing treatment protocol commonly uses pressures in the range of:
- 2.0 to 2.5 ATA for about 90 to 120 minutes (Correct answer)
- 1.1 ATA for 10 minutes
- 4.0 ATA for 5 minutes
- Surface pressure with supplemental nasal cannula
Correct answer: 2.0 to 2.5 ATA for about 90 to 120 minutes
Most wound protocols use roughly 2.0–2.5 ATA for 90–120 minutes daily.
Question 7: Which of the following is the strongest relative contraindication a technologist must screen for before wound HBO2?
- Untreated pneumothorax (Correct answer)
- Well-controlled hypertension
- Mild seasonal allergies
- History of a healed fracture
Correct answer: Untreated pneumothorax
An untreated pneumothorax can become a life-threatening tension pneumothorax during decompression.
Certified Hyperbaric Technologist Test Hyperbaric Wound Healing 2
Which physiologic mechanism most directly explains how HBO2 therapy improves healing in a hypoxic wound?