Patient Monitoring Flashcards

Which waveform component of an arterial blood pressure tracing represents the dicrotic notch?

Answer: Closure of the aortic valve

The dicrotic notch on the arterial waveform corresponds to the closure of the aortic valve at the end of systole.

A pulse oximeter reading is most likely to be unreliable in a patient with:

Answer: Severe peripheral vasoconstriction

Severe peripheral vasoconstriction reduces pulsatile blood flow to the extremities, making it difficult for the pulse oximeter to detect an accurate signal.

What is the primary purpose of the 'alarm limit' feature on patient monitors?

Answer: To alert clinicians when a parameter exceeds safe boundaries

Alarm limits are set to notify clinicians when physiological parameters deviate outside acceptable ranges, enabling timely intervention.

Which lead configuration is standard for continuous 3-lead ECG monitoring in the ICU?

Answer: Leads II, V1, and V5

Leads II, V1, and V5 are commonly used in ICU monitoring as they best detect arrhythmias and ischemic changes.

In capnography, an abnormally elevated ETCO2 value most often indicates:

Answer: Hypoventilation or increased CO2 production

Elevated end-tidal CO2 is typically caused by hypoventilation or conditions that increase CO2 production such as fever or sepsis.

When zeroing an invasive arterial pressure transducer, the stopcock reference port should be positioned at the level of the:

Answer: Phlebostatic axis (mid-axillary line at the 4th intercostal space)

The phlebostatic axis approximates the level of the right atrium and is the standard reference point for zeroing hemodynamic transducers.

Which biomedical device parameter would be most affected by motion artifact during monitoring?

Answer: Pulse oximetry SpO2 reading

Pulse oximetry relies on detecting pulsatile light absorption changes and is highly susceptible to motion artifact that mimics or obscures the pulse signal.