Field Internship Student Data Acquisition Project. (FISDAP) Airway Practice Exam

What is a sign of hypovolemia that can impact pulse oximeter accuracy?

1. Elevated heart rate

2. Weak peripheral circulation

3. Low respiratory rate

4. High fever

The correct answer is: Weak peripheral circulation

Weak peripheral circulation is a sign of hypovolemia that can significantly impact the accuracy of pulse oximeter readings. When a patient is hypovolemic, typically due to factors like blood loss or dehydration, the body tries to compensate by shunting blood away from the extremities to maintain vital organ perfusion. This can lead to decreased perfusion in peripheral areas where pulse oximeters are usually placed, such as the fingers or toes. When peripheral circulation is compromised, the pulse oximeter may struggle to obtain accurate readings because the device relies on adequate blood flow to measure the oxygen saturation in hemoglobin effectively. If the blood flow is weak, the sensor may not detect enough pulsatile blood flow or may pick up signal noise, resulting in inaccurate or unreliable readings. This highlights the importance of ensuring that the peripheral circulation is adequate before interpreting pulse oximetry results in a patient suspected of hypovolemic shock.