Patient Monitoring Systems Flashcards

What is the typical frequency range of an ECG amplifier's bandwidth for diagnostic-quality monitoring?

Answer: 0.05-150 Hz

Diagnostic-quality ECG requires 0.05-150 Hz bandwidth to capture all waveform components accurately.

What does NIBP stand for and what method do most patient monitors use to measure it?

Answer: Non-Invasive Blood Pressure - oscillometric method detecting arterial wall oscillations in an inflated cuff

NIBP (Non-Invasive Blood Pressure) uses the oscillometric method, detecting pressure oscillations as the cuff deflates.

What is the purpose of the central monitoring station in a patient monitoring system?

Answer: To display and monitor multiple patients' vital signs simultaneously from a central location

A central station receives and displays real-time vital signs from multiple bedside monitors for simultaneous observation.

When troubleshooting a patient monitor displaying 'Lead Off' for ECG, what should a biomedical technician check?

Answer: The electrode contact quality, lead wire integrity, and cable connections from patient to monitor

'Lead Off' means a break in the electrical circuit between the patient's skin and the ECG amplifier input.

What parameter does capnography monitor and what is the normal end-tidal CO2 (EtCO2) range for a healthy adult?

Answer: Exhaled carbon dioxide concentration, 35-45 mmHg

Capnography monitors CO2 concentration in exhaled breath. Normal EtCO2 is 35-45 mmHg.

What is the difference between invasive and non-invasive blood pressure monitoring, and when is invasive monitoring preferred?

Answer: Invasive uses an arterial catheter and transducer for continuous beat-to-beat monitoring in hemodynamically unstable patients

Invasive monitoring uses an arterial catheter connected to a pressure transducer for continuous real-time measurement.

What is a telemetry monitoring system and how does it differ from bedside monitoring?

Answer: Telemetry uses portable wireless transmitters on ambulatory patients, sending ECG data to a central station

Telemetry uses small portable wireless transmitters enabling continuous monitoring while patients walk around.

What are the common sources of artifact in ECG monitoring and how can they be minimized?

Answer: Common sources include muscle tremor, movement, poor electrode contact, 60Hz interference, and respiratory drift, minimized through proper skin preparation

ECG artifact comes from multiple sources that can be minimized through proper electrode application and environmental controls.

What is pulse transit time and how are newer patient monitors using it?

Answer: The time for a pulse wave to travel between two arterial sites, being explored for continuous cuff-less blood pressure estimation

PTT inversely correlates with blood pressure and enables continuous cuff-less BP estimation.

Why is it important to verify alarm settings on a patient monitor at the beginning of each patient encounter?

Answer: Alarm limits must be individualized to prevent missed events and alarm fatigue from false alarms

Alarm limits must be individualized because default or previous patient settings may not be appropriate.

What is the function of a fetal monitor and what two primary parameters does it continuously measure?

Answer: Fetal heart rate (FHR) and uterine contraction activity (tocometry)

A fetal monitor (cardiotocograph) measures fetal heart rate using Doppler ultrasound and uterine contractions using a tocodynamometer.

What is bispectral index (BIS) monitoring and what does it measure?

Answer: A processed EEG parameter that quantifies anesthesia depth on a scale of 0 to 100

BIS analyzes brain electrical activity to provide a single number representing consciousness level for guiding anesthesia depth.

A capnograph displays an abnormally low ETCO2 reading with a shark-fin waveform shape. What condition does this most likely indicate?

Answer: Bronchospasm or partial airway obstruction

A shark-fin capnogram waveform indicates obstructed exhalation, classically seen in bronchospasm or COPD exacerbation.

During routine calibration of a bedside monitor's SpO2 sensor, a BMET notices the oximeter reads 98% on a patient confirmed by ABG to have SaO2 of 84%. What is the most likely cause?

Answer: Elevated carboxyhemoglobin levels

Pulse oximetry cannot differentiate oxyhemoglobin from carboxyhemoglobin, causing falsely elevated SpO2 readings in CO poisoning.

A nurse reports that a patient's invasive arterial line is showing an overdamped waveform. Which of the following is the BEST corrective action?

Answer: Check for air bubbles, clots, or kinked tubing in the system

Overdamping is most commonly caused by air bubbles, clots, or mechanical occlusion that attenuates pressure wave transmission.

What is the primary purpose of the fast flush test (square wave test) performed on an invasive hemodynamic monitoring system?

Answer: To assess the dynamic frequency response and damping coefficient of the system

The square wave test evaluates dynamic response by analyzing the oscillations after a fast flush to determine if the system is adequately damped.

A neonatal ICU monitor alarm activates for a SpO2 reading of 80%. The BMET verifies equipment function is normal. What physiological artifact is LEAST likely responsible?

Answer: Elevated fetal hemoglobin concentration

Fetal hemoglobin (HbF) has similar optical absorption properties to adult hemoglobin at standard oximetry wavelengths and does not significantly cause inaccurate SpO2 readings.

A telemetry technician reports frequent ST-segment false alarms on a cardiac monitor. Which monitor setting change would BEST reduce these false alarms while maintaining clinical sensitivity?

Answer: Switch to a monitoring lead that provides a more stable baseline for that patient

Selecting an optimal lead with a cleaner isoelectric baseline reduces motion-induced ST baseline wander without compromising detection sensitivity.

Which parameter does a Bispectral Index (BIS) monitor measure to assess depth of anesthesia?

Answer: Processed electroencephalographic (EEG) activity

BIS monitors analyze and process raw EEG signals to produce a dimensionless index (0–100) correlating with level of consciousness.