Q.1 Which physiological parameter is measured by a pulse oximeter?
Blood glucose level
Oxygen saturation (SpO₂)
Blood pressure
Heart rate variability
Explanation - Pulse oximeters use light absorption at two wavelengths to estimate the percentage of hemoglobin bound to oxygen (SpO₂).
Correct answer is: Oxygen saturation (SpO₂)
Q.2 In an ECG monitor, the standard lead configuration that records the electrical activity between the right arm and left arm is called:
Lead I
Lead II
Lead III
aVR
Explanation - Lead I measures the potential difference between the right arm (negative) and left arm (positive) electrodes.
Correct answer is: Lead I
Q.3 What is the typical sampling frequency recommended for recording an adult ECG signal to avoid aliasing?
100 Hz
250 Hz
500 Hz
1 kHz
Explanation - The ECG signal contains frequency components up to ~150 Hz; a sampling rate of at least 500 Hz satisfies the Nyquist criterion with a safety margin.
Correct answer is: 500 Hz
Q.4 Which component in a patient monitor converts the physiological pressure into an electrical signal?
Thermistor
Photodiode
Strain‑gauge transducer
Capacitive sensor
Explanation - Strain‑gauge transducers change resistance with deformation caused by pressure, producing a proportional voltage.
Correct answer is: Strain‑gauge transducer
Q.5 The "M" in the acronym 'ABPM' (Ambulatory Blood Pressure Monitoring) stands for:
Mean
Monitoring
Measurement
Modulation
Explanation - ABPM stands for Ambulatory Blood Pressure Monitoring, which records blood pressure over 24 h while the patient goes about daily activities.
Correct answer is: Monitoring
Q.6 Which artifact is most likely to appear in an ECG trace when the patient moves their arms?
Baseline wander
Power‑line interference
Muscle (EMG) artifact
Electrode motion artifact
Explanation - Arm movement can cause the electrode–skin interface to shift, creating transient artifacts known as motion artifacts.
Correct answer is: Electrode motion artifact
Q.7 In a patient monitoring system, the term 'alarm fatigue' refers to:
The battery draining quickly
Excessive false alarms leading to desensitization
The monitor overheating
Loss of signal due to poor electrode contact
Explanation - Alarm fatigue occurs when clinicians become desensitized to frequent false alarms, potentially missing true critical events.
Correct answer is: Excessive false alarms leading to desensitization
Q.8 Which communication protocol is most commonly used for short‑range wireless transmission of patient vital signs to a bedside monitor?
Ethernet
Bluetooth Low Energy (BLE)
Wi‑Fi
ZigBee
Explanation - BLE provides low power consumption and sufficient bandwidth for transmitting vital signs over short distances.
Correct answer is: Bluetooth Low Energy (BLE)
Q.9 The accuracy of a non‑invasive blood pressure cuff is largely affected by:
Cuff size relative to arm circumference
Battery voltage
Ambient temperature
Heart rate variability
Explanation - Using an incorrectly sized cuff can cause systematic errors in measured systolic and diastolic pressures.
Correct answer is: Cuff size relative to arm circumference
Q.10 Which filter type is most suitable for removing high‑frequency noise from an ECG signal while preserving the QRS complex?
Low‑pass filter with 0.5 Hz cut‑off
High‑pass filter with 0.5 Hz cut‑off
Band‑pass filter (0.5–40 Hz)
Notch filter at 50 Hz
Explanation - A band‑pass filter passing 0.5–40 Hz retains the QRS complex while attenuating both baseline wander and high‑frequency noise.
Correct answer is: Band‑pass filter (0.5–40 Hz)
Q.11 In a multiparameter patient monitor, which parameter typically uses a thermistor as its sensing element?
Blood pressure
Pulse rate
Body temperature
Oxygen saturation
Explanation - Thermistors change resistance with temperature, making them suitable for measuring body temperature.
Correct answer is: Body temperature
Q.12 Which standard defines the safety requirements for medical electrical equipment, including patient monitors?
ISO 9001
IEC 60601-1
IEEE 802.11
FDA 21 CFR Part 11
Explanation - IEC 60601‑1 is the international standard for basic safety and essential performance of medical electrical equipment.
Correct answer is: IEC 60601-1
Q.13 A common method to prevent electrical shock to the patient from a monitor is:
Using a higher supply voltage
Implementing isolation transformers
Connecting the monitor directly to the mains
Using a metal casing
Explanation - Isolation transformers break the direct conductive path, protecting the patient from leakage currents.
Correct answer is: Implementing isolation transformers
Q.14 The term "PPG" in pulse oximetry stands for:
Photoplethysmogram
Partial Pressure Gradient
Pulse Pressure Gauge
Power Pulse Generator
Explanation - PPG is the optical measurement of blood volume changes in the microvascular bed of tissue.
Correct answer is: Photoplethysmogram
Q.15 Which of the following is a primary advantage of invasive arterial pressure monitoring over non‑invasive cuff methods?
Lower cost
Continuous real‑time pressure waveform
No risk of infection
Simpler setup
Explanation - Invasive arterial lines provide a beat‑to‑beat pressure waveform, allowing detailed analysis of cardiovascular dynamics.
Correct answer is: Continuous real‑time pressure waveform
Q.16 When designing a bedside monitor, the choice of a 5 V DC‑DC isolated power supply is primarily to:
Reduce electromagnetic interference
Provide a stable reference for analog circuitry
Increase the monitor’s weight
Enable wireless charging
Explanation - Isolated DC‑DC converters supply clean, regulated voltage while electrically separating patient-connected circuits from mains.
Correct answer is: Provide a stable reference for analog circuitry
Q.17 Which physiological signal is most commonly used to assess respiratory rate in a multiparameter monitor?
Electroencephalogram (EEG)
Impedance pneumography
Electrocardiogram (ECG)
Photoplethysmogram (PPG)
Explanation - Impedance changes across the chest during breathing are measured and converted to respiratory rate.
Correct answer is: Impedance pneumography
Q.18 In digital signal processing for ECG, the purpose of a moving‑average filter is to:
Eliminate baseline wander
Increase the amplitude of the QRS complex
Smooth high‑frequency noise
Shift the signal in time
Explanation - A moving‑average filter averages consecutive samples, reducing high‑frequency components while preserving overall shape.
Correct answer is: Smooth high‑frequency noise
Q.19 A monitor’s “trend display” is useful because it:
Shows a snapshot of a single measurement
Provides a historical view of parameter changes over time
Reduces power consumption
Eliminates the need for alarms
Explanation - Trend displays plot parameter values against time, helping clinicians detect gradual physiological changes.
Correct answer is: Provides a historical view of parameter changes over time
Q.20 The most common source of a 60 Hz interference in patient monitoring signals is:
Battery noise
Power line coupling
Radio frequency from Wi‑Fi
Mechanical vibration
Explanation - Mains electricity at 60 Hz can couple into signal leads, creating a noticeable hum in recorded waveforms.
Correct answer is: Power line coupling
Q.21 Which component in a pulse oximeter emits light at two wavelengths (typically red and infrared)?
Photodiode
LED array
Laser diode
Fluorescent tube
Explanation - LEDs of specific wavelengths are used to illuminate tissue; the reflected light is detected by a photodiode.
Correct answer is: LED array
Q.22 In the context of patient monitoring, the term "latency" refers to:
The delay between physiological change and its display on the monitor
The battery life of the device
The maximum sampling rate
The accuracy of the sensor
Explanation - Latency is the time taken for the system to process and present the measured data to the user.
Correct answer is: The delay between physiological change and its display on the monitor
Q.23 Which type of sensor is most appropriate for non‑invasive continuous blood glucose monitoring under development?
Electrochemical strip sensor
Optical fluorescence sensor
Thermistor
Piezoelectric sensor
Explanation - Research focuses on using fluorescence-based optical methods to detect glucose levels through the skin without needles.
Correct answer is: Optical fluorescence sensor
Q.24 A bedside monitor uses a 12‑bit ADC with a reference voltage of 3.3 V. What is the minimum voltage resolution (LSB size)?
0.81 mV
0.16 mV
1.6 mV
3.3 mV
Explanation - LSB = Vref / (2^12) = 3.3 V / 4096 ≈ 0.000805 V ≈ 0.81 mV.
Correct answer is: 0.81 mV
Q.25 Which of the following best describes the purpose of a “guard ring” in PCB layout of a patient monitor’s analog front‑end?
To increase the PCB thickness
To provide a low‑impedance path for high‑frequency noise away from sensitive traces
To act as a visual guide for component placement
To improve thermal dissipation
Explanation - Guard rings surround high‑impedance nodes, shunting leakage currents and reducing noise coupling.
Correct answer is: To provide a low‑impedance path for high‑frequency noise away from sensitive traces
Q.26 In a patient monitoring system, the term "CROSSTALK" typically refers to:
Signal loss due to long cables
Interference between adjacent signal channels
Power supply ripple
Software communication error
Explanation - Crosstalk occurs when a signal from one channel induces unwanted voltage in another nearby channel.
Correct answer is: Interference between adjacent signal channels
Q.27 Which of the following is a non‑invasive method to estimate cardiac output at the bedside?
Thermodilution catheter
Pulse contour analysis using arterial waveform
Echocardiography
Fick principle using oxygen consumption
Explanation - Pulse contour analysis derives cardiac output from the shape of the arterial pressure waveform without invasive catheters.
Correct answer is: Pulse contour analysis using arterial waveform
Q.28 A monitor’s alarm threshold for heart rate is set at 50 bpm (low) and 120 bpm (high). If the patient’s heart rate fluctuates between 48 bpm and 122 bpm, how many alarms will be generated in a 10‑minute interval assuming a measurement every second?
0
2
20
600
Explanation - Each second the heart rate crosses either low or high threshold, generating an alarm. In 10 min (600 s), there will be 600 measurements; assuming alternating crossing, roughly 20 alarms (10 low, 10 high) is typical; the exact number depends on pattern, but the answer expects 20.
Correct answer is: 20
Q.29 Which of the following best describes a “wet‑lab” test for calibrating a pulse oximeter?
Testing with a dry electrode on the skin
Using a calibrated gas mixture with known oxygen concentrations
Placing the sensor in a water bath
Running the device on battery power
Explanation - Calibration involves exposing the sensor to gases of known SpO₂ levels to adjust its response.
Correct answer is: Using a calibrated gas mixture with known oxygen concentrations
Q.30 The primary reason for using a differential amplifier in ECG front‑end circuits is to:
Increase the DC offset
Reject common‑mode noise such as power‑line interference
Amplify the power supply voltage
Reduce the number of electrodes needed
Explanation - Differential amplifiers amplify the voltage difference between two inputs while suppressing signals common to both, reducing interference.
Correct answer is: Reject common‑mode noise such as power‑line interference
Q.31 Which of the following is NOT a typical component of a multiparameter bedside monitor?
ECG module
Ventilator module
SpO₂ module
Non‑invasive blood pressure module
Explanation - Ventilators are separate devices; bedside monitors usually integrate ECG, SpO₂, NIBP, temperature, and respiratory rate.
Correct answer is: Ventilator module
Q.32 When a patient monitor displays a "lead off" alarm, it indicates:
The battery is low
One or more electrodes have poor contact with the skin
The device temperature is too high
The network connection is lost
Explanation - "Lead off" warns that the ECG or other electrode connections are insufficient for accurate measurement.
Correct answer is: One or more electrodes have poor contact with the skin
Q.33 In a temperature sensor for patient monitoring, a PT1000 refers to:
A photodiode with 1000 lux sensitivity
A platinum resistor with 1000 Ω at 0 °C
A pressure transducer rated for 1000 mmHg
A pulse oximeter with 1000 Hz sampling rate
Explanation - PT1000 is a platinum RTD that has a resistance of 1000 Ω at 0 °C, commonly used for precise temperature measurement.
Correct answer is: A platinum resistor with 1000 Ω at 0 °C
Q.34 Which of the following statements about the Nyquist theorem is true for patient monitoring signals?
The sampling rate must be twice the highest frequency component to avoid aliasing.
The sampling rate should be lower than the signal bandwidth to reduce data size.
Nyquist only applies to audio signals, not biomedical signals.
Aliasing can be eliminated by using a high‑pass filter only.
Explanation - Nyquist theorem is universal: sampling frequency ≥ 2 × maximum signal frequency to prevent aliasing.
Correct answer is: The sampling rate must be twice the highest frequency component to avoid aliasing.
Q.35 A typical ECG lead placement includes three electrodes: RA, LA, and LL. What does "LL" stand for?
Left leg
Lower limb
Lateral lung
Lead line
Explanation - LL denotes the left leg electrode, completing the three‑lead configuration for standard ECG.
Correct answer is: Left leg
Q.36 Which parameter is directly measured by a capnograph integrated into a patient monitor?
Partial pressure of oxygen (PaO₂)
End‑tidal carbon dioxide concentration (EtCO₂)
Blood glucose level
Mean arterial pressure
Explanation - Capnography measures the CO₂ concentration in exhaled breath, providing EtCO₂ values.
Correct answer is: End‑tidal carbon dioxide concentration (EtCO₂)
Q.37 The purpose of a “dual‑channel” ECG monitor is to:
Measure both heart rate and blood pressure simultaneously
Display two independent ECG leads at the same time
Provide redundancy in case one channel fails
Increase the sampling rate of a single lead
Explanation - Dual‑channel monitors can show two separate ECG leads, allowing clinicians to assess different cardiac vectors concurrently.
Correct answer is: Display two independent ECG leads at the same time
Q.38 Which of the following is a common technique for reducing motion artifacts in a wearable SpO₂ sensor?
Increasing LED intensity
Applying a low‑pass digital filter after acquisition
Using adhesive electrodes
Implementing adaptive filtering based on accelerometer data
Explanation - Adaptive filters can use motion information from an accelerometer to subtract motion‑related noise from the PPG signal.
Correct answer is: Implementing adaptive filtering based on accelerometer data
Q.39 In the context of patient monitoring, the term "PPV" stands for:
Pulse Pressure Variation
Peak Power Voltage
Patient Positioning Vector
Peripheral Pulse Velocity
Explanation - PPV is a dynamic preload indicator derived from arterial waveform analysis, useful in fluid responsiveness assessment.
Correct answer is: Pulse Pressure Variation
Q.40 A bedside monitor shows a temperature reading of 38.5 °C. According to standard clinical thresholds, this temperature indicates:
Hypothermia
Normal temperature
Fever
Hyperpyrexia
Explanation - A body temperature ≥38.0 °C is generally classified as fever.
Correct answer is: Fever
Q.41 When using a digital data logger for patient monitoring, the term "timestamp" refers to:
The voltage level of the recorded signal
The time at which each sample was taken
The battery status of the logger
The type of sensor used
Explanation - A timestamp records the exact time each data point is captured, enabling accurate chronological analysis.
Correct answer is: The time at which each sample was taken
Q.42 Which of the following best describes a “soft alarm” in a patient monitoring system?
An alarm that triggers only after a predefined duration of abnormal reading
A visual notification without an audible sound
An alarm that can be overridden by the patient
A low‑priority alarm that does not affect clinician response
Explanation - Soft alarms delay notification to avoid false alarms due to transient fluctuations.
Correct answer is: An alarm that triggers only after a predefined duration of abnormal reading
Q.43 In a wireless patient monitoring system, which security measure is essential to protect patient data during transmission?
Increasing the transmission power
Using AES‑128 encryption
Employing a larger antenna
Operating at a lower frequency band
Explanation - AES‑128 provides strong encryption to secure data over wireless links, complying with privacy regulations.
Correct answer is: Using AES‑128 encryption
Q.44 A monitor uses a 10‑bit ADC with a reference of 5 V to digitize a temperature sensor output ranging from 0 V to 1 V. What is the voltage resolution per LSB?
0.488 mV
4.88 mV
0.977 mV
9.77 mV
Explanation - LSB = 5 V / 1024 ≈ 4.88 mV; however, since only 0–1 V range is used, effective resolution = 1 V / 1024 ≈ 0.977 mV.
Correct answer is: 0.977 mV
Q.45 Which of the following is a typical symptom of poor grounding in a patient monitor’s analog front‑end?
Random reboot of the device
High frequency noise superimposed on physiological signals
Battery drain faster than usual
Display flickering
Explanation - Improper grounding can allow electromagnetic interference to couple into the analog circuitry, showing as noise.
Correct answer is: High frequency noise superimposed on physiological signals
Q.46 The term "artifact" in the context of EEG monitoring most commonly refers to:
A seizure event
Electrical noise from the power supply
Muscle activity or eye movement contaminating the signal
A software glitch
Explanation - EEG artifacts are undesired signals from muscle, eye movements, or external sources that obscure brain activity.
Correct answer is: Muscle activity or eye movement contaminating the signal
Q.47 Which of the following devices typically uses a “thermistor” as its primary sensing element?
Pulse oximeter
Blood pressure cuff
Core temperature probe
ECG electrode
Explanation - Thermistors are widely used in invasive or surface temperature probes for accurate temperature monitoring.
Correct answer is: Core temperature probe
Q.48 In a patient monitoring system, the abbreviation "HRV" stands for:
Heart Rate Variability
High‑Resolution Voltage
Hydraulic Resistance Valve
Heat Recovery Ventilation
Explanation - HRV quantifies the variation in time intervals between successive heartbeats and is a marker of autonomic function.
Correct answer is: Heart Rate Variability
Q.49 Which of the following is the most appropriate way to reduce baseline wander in an ECG signal?
Apply a high‑pass filter with a cut‑off around 0.5 Hz
Increase the gain of the amplifier
Add a notch filter at 60 Hz
Use a low‑pass filter at 40 Hz
Explanation - Baseline wander is low‑frequency drift; a high‑pass filter removes frequencies below ~0.5 Hz.
Correct answer is: Apply a high‑pass filter with a cut‑off around 0.5 Hz
Q.50 The ‘SpO₂’ value displayed by a pulse oximeter is calculated using which principle?
Beer‑Lambert law
Ohm’s law
Fick principle
Hooke’s law
Explanation - The Beer‑Lambert law relates light absorption to concentration of absorbing species, enabling estimation of oxygen saturation.
Correct answer is: Beer‑Lambert law
Q.51 When integrating a new sensor module into an existing patient monitor, which software layer typically handles the conversion from raw ADC counts to engineering units?
Application layer
Communication layer
Driver layer
Calibration/Signal‑Processing layer
Explanation - This layer translates raw digital values into meaningful units (e.g., mmHg, °C) using calibration curves and scaling.
Correct answer is: Calibration/Signal‑Processing layer
Q.52 A patient monitor shows a waveform labeled "Pleth" on the display. This waveform is derived from:
Electrocardiogram
Photoplethysmography
Blood pressure cuff inflation
Capnography
Explanation - The pleth waveform represents the PPG signal, reflecting blood volume changes in peripheral tissue.
Correct answer is: Photoplethysmography
Q.53 Which of the following best describes the purpose of an “isolated serial port” in a bedside monitor?
To increase data transmission speed
To prevent ground loops and protect patient safety
To reduce the number of required cables
To provide wireless connectivity
Explanation - Isolation separates patient‑connected circuits from the monitor’s internal electronics, mitigating leakage currents.
Correct answer is: To prevent ground loops and protect patient safety
Q.54 Which of the following is a key limitation of using a cuff‑based NIBP measurement during rapid patient movement?
Inability to detect systolic pressure
Delayed measurement due to cuff inflation time
Increased accuracy
Reduced battery consumption
Explanation - Movement can interfere with cuff inflation/deflation cycles, causing delays and unreliable readings.
Correct answer is: Delayed measurement due to cuff inflation time
Q.55 In a clinical setting, the acronym "STAT" on a monitor alarm typically means:
The alarm is of low priority
Immediate attention is required
The device is in standby mode
The battery is low
Explanation - STAT is used to indicate a critical alarm that demands prompt response.
Correct answer is: Immediate attention is required
Q.56 Which component in a patient monitor is responsible for converting the analog sensor voltage into a digital value?
Microcontroller
Digital Signal Processor (DSP)
Analog‑to‑Digital Converter (ADC)
Voltage regulator
Explanation - The ADC samples the analog voltage and outputs a binary representation for processing.
Correct answer is: Analog‑to‑Digital Converter (ADC)
Q.57 A monitor uses a 16‑bit DAC to generate a reference voltage for calibration. What is the smallest voltage step it can produce if the reference range is 0‑3.3 V?
0.05 mV
0.5 mV
0.08 mV
0.001 V
Explanation - Step = 3.3 V / (2^16) ≈ 3.3 V / 65536 ≈ 0.00005 V = 0.05 mV.
Correct answer is: 0.05 mV
Q.58 In an ICU, a patient monitor integrates a central venous pressure (CVP) sensor. The CVP waveform provides information about:
Left ventricular ejection fraction
Right atrial pressure dynamics
Pulmonary artery pressure
Arterial oxygen saturation
Explanation - CVP reflects pressure in the central veins, closely related to right atrial pressure.
Correct answer is: Right atrial pressure dynamics
Q.59 Which of the following best explains why patient monitors often employ a “watchdog timer” in their firmware?
To increase sampling frequency
To detect and recover from software hangs
To calibrate sensors automatically
To provide power saving mode
Explanation - A watchdog timer resets the system if the firmware becomes unresponsive, ensuring continuous operation.
Correct answer is: To detect and recover from software hangs
Q.60 When a pulse oximeter displays a low perfusion index (PI), the likely cause is:
High ambient light
Low arterial blood flow at the sensor site
Excessive sensor temperature
Battery depletion
Explanation - PI indicates the strength of the pulsatile signal; poor peripheral perfusion reduces it.
Correct answer is: Low arterial blood flow at the sensor site
Q.61 In a patient monitor, the term “FIFO buffer” refers to:
A type of analog filter
A storage structure where the first data entered is the first data retrieved
A wireless communication protocol
A power‑management circuit
Explanation - FIFO (First‑In‑First‑Out) buffers hold data temporarily, preserving temporal order before processing.
Correct answer is: A storage structure where the first data entered is the first data retrieved
Q.62 Which of the following is a typical cause of a ‘sensor disconnection’ alarm on a temperature monitoring channel?
The sensor’s thermistor has opened due to a break in the wire
The monitor’s battery is low
The monitor’s display brightness is set too low
The patient is moving rapidly
Explanation - A broken thermistor leads to an open circuit, which the monitor interprets as a disconnection.
Correct answer is: The sensor’s thermistor has opened due to a break in the wire
Q.63 Which of the following is a major advantage of using a digital filter implemented in software over an analog filter in a patient monitor?
Zero power consumption
No need for calibration
Flexibility to change filter characteristics via firmware updates
Elimination of quantization noise
Explanation - Digital filters can be reprogrammed without hardware changes, allowing easy updates to filtering requirements.
Correct answer is: Flexibility to change filter characteristics via firmware updates
Q.64 For a bedside monitor that must operate continuously for 24 hours, which battery technology provides the best balance of energy density and safety?
Lead‑acid
Lithium‑ion
Nickel‑cadmium
Alkaline
Explanation - Lithium‑ion batteries have high energy density, low self‑discharge, and are widely used in medical devices with proper safety circuits.
Correct answer is: Lithium‑ion
Q.65 In the context of patient monitoring, the term “dead‑time” refers to:
The interval when the device is powered off
The period after an alarm during which the same alarm cannot be retriggered
The time taken for the sensor to warm up
The latency between sensor placement and first measurement
Explanation - Dead‑time prevents alarm flooding by imposing a minimum interval between successive alarms of the same type.
Correct answer is: The period after an alarm during which the same alarm cannot be retriggered
Q.66 A patient monitor’s ECG module uses a gain of 1000 in its instrumentation amplifier. If the input ECG signal is 1 mV peak‑to‑peak, what is the output voltage before any clipping?
1 V
10 V
100 mV
0.1 V
Explanation - Output = Gain × Input = 1000 × 1 mV = 1000 mV = 1 V.
Correct answer is: 1 V
Q.67 Which physiological parameter can be derived from the time interval between the R‑wave of the ECG and the onset of the pulse wave measured by PPG?
Blood glucose level
Pulse transit time (PTT)
Respiratory rate
Core temperature
Explanation - PTT is the interval between cardiac electrical activity (ECG) and peripheral pulse arrival (PPG), used for blood pressure estimation.
Correct answer is: Pulse transit time (PTT)
Q.68 In a monitoring system that follows the IEC 60601‑1 standard, what does the term "MEAN time between failures (MTBF)" represent?
Average time the device stays powered on
Average interval between two consecutive device failures under normal use
Time required to calibrate the device
Duration of the warranty period
Explanation - MTBF is a reliability metric indicating expected operational life between failures.
Correct answer is: Average interval between two consecutive device failures under normal use
Q.69 A monitor uses a 12‑lead ECG configuration. Which lead is considered a “augmented” lead?
Lead I
aVR
Lead II
Lead V3
Explanation - Augmented leads (aVR, aVL, aVF) are derived by adding a reference voltage to a single limb electrode.
Correct answer is: aVR
Q.70 Which of the following statements about the use of a “reference electrode” in bio‑potential measurements is true?
It carries the main physiological signal
It provides a stable baseline for differential measurement
It amplifies the signal
It is only needed for temperature sensors
Explanation - The reference electrode establishes a common potential against which the active electrode’s signal is measured.
Correct answer is: It provides a stable baseline for differential measurement
Q.71 When designing a portable patient monitor, which factor most directly impacts the device’s overall weight?
Sampling frequency
Battery capacity
Number of software features
Display color depth
Explanation - Higher capacity batteries are heavier; they are the dominant contributor to portable device weight.
Correct answer is: Battery capacity
Q.72 In the context of patient monitoring, the abbreviation "NIBP" stands for:
Neonatal Intensive Blood Pressure
Non‑Invasive Blood Pressure
Neural Interface Bio‑Probe
Narrowband Integrated Bio‑Processor
Explanation - NIBP refers to cuff‑based blood pressure measurement methods that do not require arterial catheterization.
Correct answer is: Non‑Invasive Blood Pressure
Q.73 A monitor’s firmware includes a routine that checks sensor data every 200 ms. If the routine takes 30 ms to execute, what is the duty cycle of the processor for this task?
15 %
30 %
6 %
20 %
Explanation - Duty cycle = (execution time / period) × 100 = (30 ms / 200 ms) × 100 = 15 %.
Correct answer is: 15 %
Q.74 Which of the following best describes the role of a “spike filter” in ECG signal processing?
Eliminate high‑frequency baseline wander
Remove isolated high‑amplitude artifacts caused by electrode motion
Increase the amplitude of the QRS complex
Shift the ECG waveform in time
Explanation - Spike filters target brief, high‑amplitude disturbances without affecting the underlying ECG morphology.
Correct answer is: Remove isolated high‑amplitude artifacts caused by electrode motion
Q.75 In a multi‑parameter monitor, the term "parameter cross‑talk" typically refers to:
Electrical interference between power supplies
The effect of one physiological measurement influencing the reading of another due to shared circuitry
Data loss during wireless transmission
User interface confusion
Explanation - Cross‑talk can occur when signals from one sensor bleed into another’s measurement path.
Correct answer is: The effect of one physiological measurement influencing the reading of another due to shared circuitry
Q.76 A bedside monitor shows a sudden drop in SpO₂ from 98 % to 85 % accompanied by a rapid increase in heart rate. This pattern most likely indicates:
Patient hyperventilation
Sensor disconnection
Hypoxemic event
Battery depletion
Explanation - A drop in oxygen saturation with compensatory tachycardia suggests an acute hypoxemic episode.
Correct answer is: Hypoxemic event
Q.77 Which of the following is a key benefit of using a “modular architecture” for a patient monitoring system?
Higher power consumption
Simplified upgrades and maintenance of individual modules
Increased latency
Reduced measurement accuracy
Explanation - Modular designs allow swapping or updating specific functional blocks without redesigning the whole system.
Correct answer is: Simplified upgrades and maintenance of individual modules
Q.78 When a monitor displays a "PEEP" value, it is referring to:
Positive End‑Expiratory Pressure in mechanical ventilation
Peripheral Electrical Energy Pulse
Patient‑entered Emergency Protocol
Pulse‑Elicited Electrocardiogram Parameter
Explanation - PEEP is the pressure maintained in the lungs at the end of expiration to keep alveoli open.
Correct answer is: Positive End‑Expiratory Pressure in mechanical ventilation
Q.79 Which of the following is the most appropriate sampling interval for a respiration rate sensor that needs to capture a maximum breathing frequency of 0.5 Hz?
2 s
1 s
0.5 s
0.2 s
Explanation - Nyquist requires at least twice the max frequency: 2 × 0.5 Hz = 1 Hz → sampling interval ≤ 1 s. To ensure margin, 0.2 s (5 Hz) is suitable.
Correct answer is: 0.2 s
Q.80 In patient monitoring, a ‘trend arrow’ on a SpO₂ display pointing upward typically means:
SpO₂ is decreasing
SpO₂ is stable
SpO₂ is increasing
The sensor is disconnected
Explanation - Trend arrows indicate the direction of change; an upward arrow signifies rising oxygen saturation.
Correct answer is: SpO₂ is increasing
Q.81 Which of the following best describes why a “floating ground” is avoided in the design of patient monitoring equipment?
It reduces electromagnetic interference
It can cause unpredictable voltage offsets leading to measurement errors
It improves battery life
It enhances wireless communication range
Explanation - Floating grounds lack a defined reference, making the system susceptible to noise and offsets.
Correct answer is: It can cause unpredictable voltage offsets leading to measurement errors
Q.82 A monitor's ECG leads are connected in a "Wheatstone bridge" configuration. What is the main advantage of this arrangement?
Increased signal amplitude
Improved common‑mode rejection
Simplified wiring
Reduced power consumption
Explanation - The Wheatstone bridge balances resistive paths, enhancing rejection of common‑mode interference.
Correct answer is: Improved common‑mode rejection
Q.83 Which of the following is a typical data format used to export patient vital signs from a monitoring system for electronic health records?
XML
JPEG
MP3
PDF
Explanation - XML (eXtensible Markup Language) provides a structured, interoperable format for exchanging clinical data.
Correct answer is: XML
Q.84 The term “iso‑chronous” in data transmission for patient monitors means:
Data is sent with guaranteed delivery but no timing constraints
Data is transmitted continuously at regular intervals with bounded latency
Data is encrypted end‑to‑end
Data is compressed before transmission
Explanation - Iso‑chronous transfer ensures timely delivery suitable for real‑time physiological data.
Correct answer is: Data is transmitted continuously at regular intervals with bounded latency
Q.85 When a patient monitor’s battery indicator shows a red icon, the most appropriate immediate action is:
Increase the monitor’s brightness
Replace or recharge the battery before continued use
Ignore it; the monitor will continue working
Turn off all alarms
Explanation - A red battery icon signals low battery; continuing operation could lead to sudden shutdown and loss of monitoring.
Correct answer is: Replace or recharge the battery before continued use
Q.86 In an arterial line pressure transducer, the term “zeroing” refers to:
Setting the baseline pressure to atmospheric pressure when the patient is not connected
Increasing the gain of the amplifier
Calibrating the temperature sensor
Adjusting the alarm thresholds
Explanation - Zeroing removes offset caused by fluid column and transducer mechanics before connecting to the patient.
Correct answer is: Setting the baseline pressure to atmospheric pressure when the patient is not connected
Q.87 Which of the following physiological signals is most sensitive to motion artifacts when using a wrist‑worn wearable monitor?
Electrocardiogram (ECG)
Photoplethysmogram (PPG)
Blood pressure
Core temperature
Explanation - PPG relies on optical detection of blood volume changes, which are easily disturbed by movement of the sensor relative to skin.
Correct answer is: Photoplethysmogram (PPG)
Q.88 A monitor’s ECG trace shows a flat line (isoelectric) for several seconds while the patient is still alive. The most likely cause is:
Asystole
Lead disconnection
Battery failure
Power‑line interference
Explanation - A flat ECG with a living patient usually indicates a loss of electrode contact rather than true asystole.
Correct answer is: Lead disconnection
Q.89 Which of the following best describes the purpose of a “digital twin” in advanced patient monitoring systems?
A backup copy of the monitor’s firmware
A virtual replica of the patient’s physiology for predictive analytics
A duplicate hardware unit for redundancy
A wireless charger for the device
Explanation - Digital twins simulate real‑time patient data to forecast trends and aid clinical decision‑making.
Correct answer is: A virtual replica of the patient’s physiology for predictive analytics
Q.90 Which of the following is a standard communication protocol used to integrate patient monitors with hospital information systems (HIS)?
HL7
SMTP
FTP
SNMP
Explanation - Health Level‑7 (HL7) defines messaging standards for exchanging clinical data between devices and HIS.
Correct answer is: HL7
Q.91 When a monitor’s SpO₂ reading is consistently lower than expected, a common corrective action is to:
Increase the sensor’s LED current
Apply a conductive gel to the sensor
Warm the sensor to improve perfusion
Switch to a higher‑resolution ADC
Explanation - Warming the sensor site can increase peripheral blood flow, improving the quality of the PPG signal and SpO₂ accuracy.
Correct answer is: Warm the sensor to improve perfusion
Q.92 In a patient monitoring system, a “watchdog timer” is set to 2 seconds. If the firmware fails to reset the timer within this interval, the system will:
Enter sleep mode
Perform a software reset
Increase the sampling rate
Shut down the power supply
Explanation - The watchdog timer forces a reset when the main program becomes unresponsive, restoring normal operation.
Correct answer is: Perform a software reset
Q.93 A monitor’s built‑in algorithm calculates the “Shock Index” as heart rate divided by systolic blood pressure. A Shock Index > 0.9 typically suggests:
Hypertension
Hypovolemia or shock
Bradycardia
Normal hemodynamics
Explanation - An elevated Shock Index indicates disproportionate tachycardia relative to blood pressure, a sign of circulatory compromise.
Correct answer is: Hypovolemia or shock
Q.94 Which of the following is an advantage of using a “dual‑frequency” (red/infrared) PPG sensor versus a single‑wavelength sensor for SpO₂ measurement?
Higher power consumption
Ability to differentiate between oxy‑ and deoxy‑hemoglobin
Simpler signal processing
Reduced need for calibration
Explanation - Dual wavelengths exploit differing absorption spectra of oxy‑ and deoxy‑hemoglobin to compute saturation.
Correct answer is: Ability to differentiate between oxy‑ and deoxy‑hemoglobin
Q.95 When a bedside monitor displays a ‘low battery’ warning while plugged into AC power, the most plausible explanation is:
The AC outlet is faulty
The internal battery is not charging due to a failed charging circuit
The monitor’s firmware is corrupted
The patient’s vitals are abnormal
Explanation - Even when connected to AC, a defective charging circuit can prevent battery replenishment, triggering the warning.
Correct answer is: The internal battery is not charging due to a failed charging circuit
Q.96 Which of the following best defines the term “electrocardiographic axis deviation”?
A shift in the average direction of the heart’s electrical depolarization
A change in the heart rate variability
An alteration in the amplitude of the QRS complex
A delay in the P‑wave onset
Explanation - Axis deviation describes the orientation of the mean QRS vector in the frontal plane.
Correct answer is: A shift in the average direction of the heart’s electrical depolarization
Q.97 A monitor’s firmware version is updated from 2.1.3 to 2.2.0. Which type of change is most likely indicated by the increment from ‘1’ to ‘2’ in the middle number?
Bug fix
Minor feature addition or improvement
Major redesign
Security patch
Explanation - Semantic versioning uses MAJOR.MINOR.PATCH; increasing the MINOR number indicates added functionality while maintaining compatibility.
Correct answer is: Minor feature addition or improvement
Q.98 In a patient monitor that uses Bluetooth Low Energy (BLE) to transmit data, which of the following is a typical maximum range under ideal indoor conditions?
5 m
10 m
30 m
100 m
Explanation - BLE typically achieves up to ~30 m (≈100 ft) line‑of‑sight indoor, though walls can reduce range.
Correct answer is: 30 m
Q.99 A patient monitor uses a 24‑bit sigma‑delta ADC for temperature measurement. What is the primary advantage of a sigma‑delta converter in this application?
Very high sampling speed
Excellent noise shaping and high resolution
Low cost compared to SAR converters
Built‑in temperature compensation
Explanation - Sigma‑delta ADCs oversample and filter noise, yielding high resolution suitable for precise temperature sensing.
Correct answer is: Excellent noise shaping and high resolution
Q.100 Which of the following best describes the purpose of a “baseline correction” algorithm in a SpO₂ monitor?
To adjust for long‑term drift in sensor output due to temperature changes
To increase the LED intensity
To speed up data transmission
To calibrate the battery level
Explanation - Baseline correction removes slow changes in the PPG signal unrelated to pulsatile blood flow, improving accuracy.
Correct answer is: To adjust for long‑term drift in sensor output due to temperature changes
Q.101 In a hospital setting, which of the following is a regulatory requirement for patient monitors regarding data security?
All data must be stored in plaintext on local memory
Encryption of data in transit and at rest
No need for authentication mechanisms
Unlimited data retention period
Explanation - Regulations such as HIPAA mandate encryption to protect patient health information during transmission and storage.
Correct answer is: Encryption of data in transit and at rest
Q.102 A monitor’s ECG display shows a "PVC" annotation. What does PVC stand for?
Premature Ventricular Contraction
Positive Voltage Curve
Peripheral Vascular Collapse
Pulmonary Valve Closure
Explanation - PVC denotes an early beat originating from the ventricles, appearing as a wide, abnormal QRS complex.
Correct answer is: Premature Ventricular Contraction
Q.103 Which of the following best explains why a patient monitor’s display might use a “segmented LCD” rather than a full‑color TFT screen?
Segmented LCD consumes less power, extending battery life
Segmented LCD provides higher resolution
Segmented LCD allows for 3D graphics
Segmented LCD is more expensive
Explanation - Segmented LCDs are low‑power, ideal for battery‑operated devices where only numeric/alarm information is needed.
Correct answer is: Segmented LCD consumes less power, extending battery life
Q.104 In a multiparameter monitor, which of the following signals is typically derived from the ECG rather than being measured directly?
Heart rate
Respiratory rate
SpO₂
Blood pressure
Explanation - Heart rate is calculated by detecting R‑wave intervals in the ECG signal.
Correct answer is: Heart rate
Q.105 A monitor’s alarm limits for heart rate are set to 50 bpm (low) and 130 bpm (high). If the measured heart rate oscillates between 48 bpm and 132 bpm, how many low‑high alarm pairs will be generated in 5 minutes assuming a measurement every second?
0
5
10
600
Explanation - Each second the rate crosses a limit; assuming alternating low and high breaches, 5 min = 300 s → roughly 10 low‑high pairs (one low and one high every 30 s).
Correct answer is: 10
Q.106 Which of the following is a typical consequence of not performing regular calibration of a pressure transducer in a patient monitor?
Increased battery life
Gradual drift leading to inaccurate blood pressure readings
Faster data transmission
Reduced display brightness
Explanation - Pressure transducers can drift over time; calibration restores accuracy.
Correct answer is: Gradual drift leading to inaccurate blood pressure readings
Q.107 In the context of patient monitoring, the abbreviation "ABG" stands for:
Arterial Blood Gas
Automated Blood Glucose
Acoustic Breath Graph
Advanced Bio‑Signal Generator
Explanation - ABG analysis provides measurements of PaO₂, PaCO₂, pH, and other blood gas parameters.
Correct answer is: Arterial Blood Gas
Q.108 Which of the following best describes the function of a “soft‑start” circuit in the power supply of a patient monitor?
To gradually increase voltage at power‑on, reducing inrush current and stress on components
To boost the signal amplitude
To encrypt data during transmission
To calibrate the temperature sensor
Explanation - Soft‑start circuits limit initial surge current, protecting components and improving reliability.
Correct answer is: To gradually increase voltage at power‑on, reducing inrush current and stress on components
Q.109 A monitor’s ECG leads are labelled "LA", "RA", and "LL". Which anatomical position does the "LA" electrode correspond to?
Left arm
Right arm
Left leg
Right leg
Explanation - "LA" stands for Left Arm, one of the standard limb electrodes in ECG acquisition.
Correct answer is: Left arm
Q.110 Which of the following signal processing techniques is most effective at removing 50/60 Hz power‑line interference from physiological recordings?
Low‑pass filtering at 30 Hz
Notch filter centered at 50/60 Hz
High‑pass filtering at 0.5 Hz
Median filtering
Explanation - A notch filter attenuates a narrow band around the mains frequency, effectively suppressing power‑line noise.
Correct answer is: Notch filter centered at 50/60 Hz
Q.111 When a bedside monitor displays a "PE" (Peak Expiratory) pressure value, it is most likely related to which therapeutic modality?
Mechanical ventilation
Dialysis
Infusion therapy
Physical therapy
Explanation - PE (Peak Expiratory) pressure is a parameter in ventilator settings, indicating the maximum pressure during exhalation.
Correct answer is: Mechanical ventilation
Q.112 A monitor’s firmware includes a routine that performs a Fast Fourier Transform (FFT) on the ECG signal. What is the primary purpose of this operation?
To increase the sampling rate
To convert the signal from time domain to frequency domain for spectral analysis
To compress the data for storage
To adjust the gain of the amplifier
Explanation - FFT provides frequency‑domain representation, useful for detecting noise components or arrhythmias.
Correct answer is: To convert the signal from time domain to frequency domain for spectral analysis
Q.113 In a patient monitor, the term “dead‑band” is used to describe:
A range of values where no alarm is generated
The time taken for the device to boot up
The maximum voltage the device can output
The storage capacity of the internal memory
Explanation - Dead‑band defines a tolerance zone around a set point where minor fluctuations do not trigger alarms.
Correct answer is: A range of values where no alarm is generated
Q.114 Which of the following is a common method to verify the accuracy of a patient monitor’s temperature sensor before clinical use?
Comparing its reading with a calibrated reference thermometer
Increasing the monitor’s brightness
Changing the battery
Updating the firmware
Explanation - Calibration against a known standard ensures temperature measurements are within acceptable error limits.
Correct answer is: Comparing its reading with a calibrated reference thermometer
Q.115 A monitor uses a 4‑wire configuration for its temperature sensor (RTD). What is the main advantage of a 4‑wire over a 2‑wire configuration?
Reduced cost
Elimination of lead resistance error
Higher temperature range
Simpler wiring
Explanation - The 4‑wire method separates current‑carrying and voltage‑sensing leads, cancelling out resistance of the leads.
Correct answer is: Elimination of lead resistance error
Q.116 Which of the following best explains why patient monitors often include a “snooze” function for alarms?
To permanently disable alarms
To temporarily silence non‑critical alarms while retaining the ability to reactivate them
To increase the monitor’s processing speed
To reset the battery indicator
Explanation - Snooze allows clinicians to mute an alarm for a short period, reducing disturbance while preserving safety.
Correct answer is: To temporarily silence non‑critical alarms while retaining the ability to reactivate them
Q.117 In the IEC 60601‑1 standard, the term “IEC” stands for:
International Electrotechnical Commission
Institute of Electrical Engineers
Integrated Electronic Controls
Internal Emergency Circuit
Explanation - IEC is the organization that develops international standards for electrical and electronic technologies, including medical devices.
Correct answer is: International Electrotechnical Commission
Q.118 Which of the following physiological signals is most directly used to calculate the “cardiac output” via the thermodilution method?
Arterial pressure waveform
Blood temperature change after a cold saline injection
ECG R‑wave interval
SpO₂ saturation
Explanation - Thermodilution measures temperature change downstream of an injected bolus, from which cardiac output is derived.
Correct answer is: Blood temperature change after a cold saline injection
Q.119 A monitor’s ECG leads are placed incorrectly, resulting in a mirror image of the normal waveform. This error is known as:
Lead reversal
Baseline drift
Signal clipping
Sampling aliasing
Explanation - Reversing the polarity of leads produces an inverted ECG trace.
Correct answer is: Lead reversal
Q.120 Which of the following is the most appropriate method to reduce electromagnetic interference (EMI) from nearby equipment in a patient monitor’s analog front‑end?
Increase the LED brightness
Add shielding and proper grounding
Raise the supply voltage
Use a higher‑resolution ADC
Explanation - Effective shielding and grounding create a Faraday cage and reference point, minimizing EMI pickup.
Correct answer is: Add shielding and proper grounding
Q.121 In a patient monitor, the term "PPG waveform morphology" is primarily used to assess:
Blood glucose trends
Respiratory effort
Peripheral vascular health and perfusion
Neural activity
Explanation - PPG morphology (e.g., dicrotic notch, amplitude) reflects vascular compliance and blood flow quality.
Correct answer is: Peripheral vascular health and perfusion
Q.122 Which of the following best describes the function of a “watchdog timer” in a patient monitor’s microcontroller?
To schedule regular data backups
To detect software hangs and reset the processor
To adjust the gain of analog amplifiers
To control the LCD backlight intensity
Explanation - A watchdog timer forces a reset if the firmware fails to service it within a specified interval, ensuring reliability.
Correct answer is: To detect software hangs and reset the processor
Q.123 A monitor’s display shows a temperature of 37.0 °C with a trend arrow pointing downwards. This likely indicates:
The patient is becoming hypothermic
The sensor is malfunctioning
The monitor’s battery is low
The patient’s heart rate is decreasing
Explanation - A decreasing temperature trend suggests a drop toward hypothermia if the downward trend continues.
Correct answer is: The patient is becoming hypothermic
Q.124 Which of the following is a typical requirement for a patient monitor’s data logger to comply with regulatory standards?
Unlimited data storage capacity
Time‑stamped records with at least 1‑second resolution
Continuous audible alarms
Colorful graphical interface
Explanation - Regulations often require precise time‑stamping of vital sign data for traceability and clinical review.
Correct answer is: Time‑stamped records with at least 1‑second resolution
Q.125 In a patient monitor, which of the following is the most common reason for using a differential ADC instead of a single‑ended ADC?
To reduce power consumption
To improve common‑mode noise rejection
To increase the number of channels
To simplify PCB layout
Explanation - Differential ADCs measure the voltage difference between two inputs, suppressing noise that appears equally on both lines.
Correct answer is: To improve common‑mode noise rejection
Q.126 Which of the following best defines the term “patient isolation” in the context of medical device design?
Physical separation of the patient from the device
Electrical separation to prevent leakage currents from reaching the patient
Using a wireless connection instead of cables
Applying a sterile cover to the device
Explanation - Patient isolation ensures safety by electrically isolating patient‑connected circuitry from mains and internal electronics.
Correct answer is: Electrical separation to prevent leakage currents from reaching the patient
Q.127 A bedside monitor’s built‑in algorithm calculates the “Respiratory Sinus Arrhythmia (RSA)” index using ECG and respiration signals. RSA is primarily an indicator of:
Cardiac arrhythmias
Autonomic nervous system activity
Blood glucose fluctuations
Pulmonary embolism
Explanation - RSA reflects heart rate variability linked to the breathing cycle, representing parasympathetic modulation.
Correct answer is: Autonomic nervous system activity
Q.128 Which of the following is the most appropriate method to verify that a patient monitor’s alarm thresholds are set correctly before patient connection?
Run the self‑test routine and observe simulated alarms
Check the battery level
Adjust the screen brightness
Update the firmware
Explanation - Self‑test modes generate test signals that trigger alarms, confirming correct threshold configuration.
Correct answer is: Run the self‑test routine and observe simulated alarms
Q.129 Which of the following is an advantage of using a “fiber‑optic” link for transmitting patient data between a bedside monitor and a central station?
Higher electromagnetic immunity
Lower cost than Ethernet
Simpler connector design
Ability to power the monitor through the fiber
Explanation - Fiber‑optic cables are immune to EMI, making them ideal for transmitting sensitive medical data in electrically noisy environments.
Correct answer is: Higher electromagnetic immunity