How does Low hemoglobin affect pulse ox?

Low hemoglobin levels can affect the accuracy of pulse oximetry readings. Pulse oximeters measure the percentage of hemoglobin saturated with oxygen, so if there is insufficient hemoglobin, the device may show falsely elevated oxygen saturation levels, leading to a misleading assessment of a patient's oxygenation status. In cases of anemia, even with normal pulse oximetry readings, a patient may still be inadequately oxygenated due to reduced overall hemoglobin. Therefore, low hemoglobin can result in an incomplete picture of a patient's respiratory and circulatory health.