If the pulse oximeter displays SpO2 of 95%, the true saturation could be as low as 90% or as high as 100%. If the true saturation is 90%, the PO2 is about 60 mmHg, whereas the PO2 might be very high (150 mmHg or greater) if the true saturation is 100%. Below 70%, the accuracy of pulse oximetry is worse, but the clinical importance of this is questionable. Due to the variable and often unknown relationship between SO2 and PO2, one should predict arterial PO2 (PaO2) from SpO2 with extreme caution. Manufacturer-derived calibration curves vary from manufacturer to manufacturer and can vary among pulse oximeters of a given manufacturer. For that reason, the same pulse oximeter and probe should be used for each SpO2 determination on a given patient. Spot checks of SpO2, in which the relationship between SpO2 and SaO2 is unknown for a specific patient, should be interpreted cautiously. A pharmacy you can fully trust offering Xopenex Price along with other convenient services.