Final answer:
When the pulse rate on the pulse oximeter differs from the EKG monitor, the O2 saturation reading may be inaccurate, which could reflect technical problems or physiological issues. The pulse oximeter measures percent saturation, where normal levels range from 95-100 percent, with lower values indicating hypoxemia.
Step-by-step explanation:
If the pulse rate on the pulse oximeter differs from the EKG monitor, the O2 saturation reading may be inaccurate. Percent saturation is monitored using a pulse oximeter placed on a thin body part, such as the tip of the patient's finger. This device emits two wavelengths of light through the tissue and a photodetector measures the light that exits. The percent saturation indicates the percentage of hemoglobin sites occupied by oxygen in the blood. A normal reading ranges from 95-100 percent, with lower percentages reflecting hypoxemia, or low blood oxygen levels.
Additionally, oxygen levels can be directly monitored through an arterial stick, which measures the partial pressure of oxygen (pO2) in millimeters of mercury (mm Hg). Discrepancies between the pulse oximeter and EKG could suggest a problem with either device or indicate physiological issues such as pulse rate variability or poor perfusion.