Professional Practice, Safety, and Ethics
Professional Practice, Safety, and Ethics tests whether you apply ALARA, understand output indices, work within scope, and handle consent, documentation and incidental findings honestly.
Core rules
- ALARA: use the lowest output and shortest dwell time that yield a diagnostic study.
- Thermal index estimates temperature rise; mechanical index estimates cavitation risk. Regulatory limits are ISPTA 720 mW/cm² and MI 1.9; obstetric and ophthalmic practice generally aims for TI below 1.0.
- Doppler and color increase energy deposition; narrow the color box, reduce dwell time and turn off Doppler when not needed.
- Stay within your scope of practice; delegate only tasks permitted by policy and training.
- Obtain and document informed consent, including limitations of the study.
- Incidental findings must be reported and routed appropriately, not omitted.
- Protect patient data under HIPAA and disclose errors transparently.
Worked example
An 8-week transvaginal scan displays a thermal index of 1.3. The correct response is to lower acoustic power, stop color and spectral Doppler, reduce dwell time, and confirm the preset is obstetric. The reasoning is that the first trimester is the most radiosensitive period and TI is an estimate of temperature rise, so the study should be completed at the lowest output that remains diagnostic - not abandoned, and not continued unchanged.
Traps that cost marks
Confusing MI with TI; assuming first-trimester Doppler is risk-free; documenting only normal findings and omitting study limitations; and reporting an incidental finding verbally without a written record.