Medical Equipment Function Flashcards

What does an automated external defibrillator (AED) analyze before advising a shock?

Answer: The patient's ECG rhythm to determine if it is a shockable rhythm (VF or pulseless VT)

An AED analyzes the ECG rhythm to determine if it is ventricular fibrillation or pulseless ventricular tachycardia.

In a CT scanner, what is the function of the slip ring?

Answer: To provide continuous electrical connection between the rotating gantry and the stationary frame, enabling helical scanning

Slip rings provide continuous electrical connection allowing unlimited rotation for helical/spiral scanning.

What is the purpose of the beam hardening filter in an X-ray tube assembly?

Answer: To remove low-energy X-ray photons that would only increase patient skin dose without contributing to image formation

Beam hardening filters absorb low-energy photons that would be absorbed by superficial tissue, reducing patient dose.

How does a biphasic defibrillation waveform differ from a monophasic waveform, and why is it preferred?

Answer: Biphasic delivers current in two directions, requiring less energy for effective defibrillation

Biphasic waveforms achieve higher first-shock success rates at lower energies (120-200J vs 360J monophasic), reducing myocardial damage.

What is the role of the collimator in an X-ray system?

Answer: To restrict the X-ray beam to the area of clinical interest, reducing patient dose and improving image quality

The collimator uses adjustable lead shutters to restrict the beam to the area of interest.

What does the term 'duty cycle' refer to in the context of an electrosurgical unit?

Answer: The ratio of active current delivery time to total cycle time, which differentiates cutting from coagulation modes

CUT mode uses continuous waveform (100% duty cycle) for tissue vaporization; COAGULATION uses intermittent waveform (6% duty cycle) for protein denaturation.