Mixed Deck — All CHT Topics Flashcards
100 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 20 Mixed Deck — All CHT Topics flashcards as text
The Frank-Starling mechanism of the heart states that increased ventricular preload leads to:
Answer: Increased stroke volume due to enhanced myofilament overlap
The Frank-Starling law describes how greater ventricular filling stretches myocardial fibers, optimizing actin-myosin overlap and increasing the force of contraction and stroke volume.
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.
What is the maximum allowable oxygen concentration in a multiplace chamber breathing air, per NFPA 99 guidelines?
Answer: 23.5%
NFPA 99 sets 23.5% as the oxygen-enriched atmosphere threshold; chamber ambient O2 must be maintained below this level to reduce fire risk.
In the mnemonic VENTID-C used to identify early CNS oxygen toxicity symptoms, the 'V' stands for:
Answer: Vision changes such as tunnel vision
In VENTID-C, V stands for Visual disturbances (tunnel vision), which is an early warning sign of CNS oxygen toxicity preceding convulsions.
Active seizure disorder is classified as which type of contraindication to HBO therapy?
Answer: Relative contraindication that may be managed with precautions and monitoring
Active seizure disorder is a relative contraindication; HBO can proceed with physician evaluation, optimized seizure management, and heightened monitoring for oxygen toxicity warning signs.
A patient receiving HBO for a non-healing wound reports new chest tightness and shortness of breath after the 30th treatment. This presentation is MOST consistent with:
Answer: Pulmonary oxygen toxicity
Chest tightness and dyspnea after many HBO sessions suggests pulmonary oxygen toxicity (Lorraine Smith effect) from cumulative oxygen exposure.
Which condition describes gas bubbles forming in venous blood from nitrogen supersaturation after rapid ascent?
Answer: Type I decompression sickness
Type I DCS involves musculoskeletal and lymphatic manifestations from nitrogen bubble formation in venous blood and tissues.
During pre-dive assessment, the technician discovers the patient has not eaten for 8 hours. The BEST course of action is to:
Answer: Provide a light snack before treatment to prevent hypoglycemia
HBO therapy lowers blood glucose; a light meal before treatment helps prevent hypoglycemia during the session.
How should emerging trends in hyperbaric chamber emergency procedures be incorporated into practice?
Answer: Through evidence-based evaluation and systematic integration into existing protocols
Evidence-based evaluation ensures new trends are valid and beneficial before integration, maintaining quality while embracing beneficial advances.
Which factor is most important when determining treatment frequency?
Answer: Evidence-based clinical guidelines and patient response
Treatment frequency should be based on evidence-based clinical guidelines and individual patient response to ensure optimal outcomes.
When faced with a conflict of interest, what is the appropriate course of action?
Answer: Disclose the conflict and recuse yourself from the situation
Disclosing conflicts of interest and recusing oneself ensures objective decision-making and maintains professional integrity.
Which gas law is most directly applied when calculating the total pressure of a gas mixture in a hyperbaric chamber?
Answer: Dalton's Law of Partial Pressures
Dalton's Law states total pressure equals the sum of individual partial pressures of all gases in the mixture.
A wound care patient has a blood glucose of 55 mg/dL just before their scheduled HBO session. What is the MOST appropriate action?
Answer: Treat the hypoglycemia, recheck glucose, and defer HBO until glucose is stable and within acceptable range
Active hypoglycemia must be corrected and glucose stabilized before initiating HBO therapy, which can further lower blood glucose.
Which gas law explains why a patient's sinuses or tooth abscess may become painful during hyperbaric compression?
Answer: Boyle's Law — gas volume decreases as pressure increases on trapped gas spaces
Boyle's Law describes the inverse relationship between pressure and gas volume; trapped gas in sinuses, teeth, or middle ears compresses during descent, causing pain.
Which competency is most essential for professionals working in hyperbaric chamber emergency procedures?
Answer: Comprehensive knowledge combined with practical application skills
Effective practice requires both comprehensive knowledge and practical application skills, as theory alone cannot address real-world challenges.
What physiological effect of HBO directly promotes angiogenesis in hypoxic wound beds?
Answer: Cyclic hyperoxia–normoxia stimulating VEGF release
Alternating high and normal O2 tensions between HBO sessions stimulates vascular endothelial growth factor (VEGF) and new capillary formation.
A CHT is asked by a patient's attorney to provide a copy of the patient's hyperbaric treatment records. The correct response is to:
Answer: Direct the request to the facility's medical records department and follow HIPAA release-of-information procedures
Record release requests must be handled through official medical records procedures with proper patient authorization, following HIPAA guidelines.
When a monoplace hyperbaric chamber is pressurized with 100% oxygen, the operator controls depth primarily via:
Answer: A needle or metering valve on the supply line and a pressure regulator set to the desired treatment depth
A supply regulator preset to the treatment pressure combined with a metering valve delivers and holds chamber pressure at the prescribed depth.
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.
When monitoring a diabetic patient receiving HBO therapy, which adverse effect is of GREATEST concern during the treatment session?
Answer: Hypoglycemia
HBO therapy can lower blood glucose levels; diabetic patients are at risk for hypoglycemia during and after treatment.