Which patient condition may lead to pulse oximetry errors due to reduced blood flow?

Reduced blood flow is a critical factor that can affect the accuracy of pulse oximetry readings. In patients experiencing hypotension, which is characterized by abnormally low blood pressure, there may be inadequate perfusion of peripheral tissues. This diminished blood flow can lead to lower blood volume reaching the fingers or other measuring sites where pulse oximeters are typically placed. As a result, the pulse oximeter may struggle to detect the oxygen saturation levels accurately, potentially leading to misleading or erroneous readings.

In contrast, conditions like hyperthermia, dehydration, or a heart murmur do not inherently cause a significant reduction in peripheral blood flow to the extent that hypotension does. Hyperthermia involves an elevated body temperature, which can lead to increased blood flow to the skin; dehydration may influence overall circulatory volume but not necessarily to the same immediate impact as hypotension; and a heart murmur pertains to abnormal blood flow dynamics but does not directly correlate with reduced peripheral perfusion in the same way. Thus, hypotension stands out as the condition most likely to interfere with accurate pulse oximetry due to its direct effects on blood flow.