Basic Ultrasound Physics — Flashcards

Flashcard 1: A notch or dip in the alveolar plateau (Phase III) of a capnography waveform represents:_____

Answer: Curare clefts

Extra: Curare clefts appear as a notch or dip in the alveolar plateau (Phase III) of the capnogram. This finding indicates that the patient is making spontaneous respiratory efforts during mechanical ventilation, typically when neuromuscular blockade is wearing off or is insufficient.

Flashcard 2: The tube used for performing gastric lavage is an _____ tube.

Answer: Ewald

Flashcard 3: The click-or-pop sensation in spinal anesthesia is encountered while piercing _____ and _____ mater.

Answer: ligamentum flavum; dura

Flashcard 4: During CPR, a sudden sustained increase in ETCO2 (capnography) represents:_____

Answer: Return of spontaneous circulation (ROSC)

Extra: A sudden sustained increase in ETCO2 (typically >35-40 mmHg) is a reliable indicator of ROSC during CPR.

Flashcard 5: A capnography waveform with an **elevated baseline** (where CO2 does not return to zero during inspiration) represents:_____

Answer: **Exhausted CO2 absorber** (leading to rebreathing)

Flashcard 6: Which condition is characterized by a 'shark-fin' appearance on a capnography waveform?

Answer: Bronchospasm (e.g., Asthma, COPD)

Flashcard 7: _____flurane can produce increased blood pressure and heart rate when the concentrations are rapidly increased

Answer: Des

Flashcard 8: The incidence of PDPH is _____ when the needle bevel is placed in the long axis of the neuraxis

Answer: lesser (more/less)

Flashcard 9: A biphasic or "dual-peak" capnography waveform (double-sloped expiratory plateau) is characteristic of:

Answer: Single lung transplant

Extra: A biphasic or "dual-peak" capnogram (double-sloped expiratory plateau) occurs in single-lung transplant patients because the native and transplanted lungs have different compliance and resistance (different time constants), leading to asynchronous emptying.