Understanding Pulse Oximetry

What principle does pulse oximetry primarily rely on to measure oxygen saturation?

• Electrical conductivity of blood

• Absorption of specific wavelengths of light by oxygenated and deoxygenated hemoglobin

• Magnetic resonance of oxygen molecules

• Pressure changes in the arteries

Which two wavelengths of light are used in pulse oximetry?

• Ultraviolet and infrared

• Blue and green

• Red and infrared

• Green and ultraviolet

What does a pulse oximeter directly measure?

• Arterial blood pressure

• Heart rate

• Oxygen saturation of hemoglobin in arterial blood

• Carbon dioxide levels in the blood

Where is a pulse oximeter most commonly placed for an accurate reading?

• On the earlobe

• On the fingertip

• Around the wrist

• On the forehead

What is the normal range of oxygen saturation (SpO2) in healthy individuals, as measured by a pulse oximeter?

• 70-80%

• 80-90%

• 95-100%

• 100-105%

How does the presence of carbon monoxide in the blood affect pulse oximetry readings?

• It causes falsely low readings

• It causes falsely high readings

• It has no effect on the readings

• It causes the device to malfunction

What is the term for the graph displayed on a pulse oximeter that shows the flow of blood with each heartbeat?

• Echocardiogram

• Plethysmograph

• Cardiogram

• Oximetry curve

In addition to oxygen saturation, what other vital sign can most pulse oximeters measure?

• Blood glucose levels

• Blood pressure

• Heart rate

• Respiratory rate

Why might a pulse oximeter give an inaccurate reading?

• If the patient is wearing nail polish

• If the patient is perfectly still

• If the device is used outdoors in cold weather

• All of the above

What is a potential limitation of using pulse oximetry in patients with anemia?

• It can overestimate the oxygen saturation level

• It can underestimate the oxygen saturation level

• It cannot detect anemia

• Both A and C