- Indication of respiratory efficiency, not confirmation
- Cannot measure the amount of hemoglobin, only the oxygen saturation of the hemoglobin that is present
- Other clinical assessments must be performed as well
- Measurement may be difficult to obtain on some patients due to hypovolemia, hypothermia, anemia, nail polish, carbon monoxide poisoning
- Measures saturation of hemoglobin; it can- not distinguish between oxygen saturation and carbon monoxide saturation.
- Time delay between patient's pulse oximeter reading & current RR