What is the sampling rate for the SpO2 channel?

The sampling rate for the SpO2 channel is typically set at 25Hz. This lower sampling rate is sufficient for capturing the pulsatile nature of blood flow within the peripheral tissues where pulse oximetry sensors are applied. The SpO2 signal is primarily concerned with detecting variations in light absorption by oxygenated and deoxygenated hemoglobin, which occurs in a relatively slow time frame compared to other physiological signals.

Using a sampling rate of 25Hz offers a good balance between accurately capturing oxygen saturation levels and conserving battery life and processing power in monitoring devices. Higher sampling rates, while more precise, may result in unnecessary data that does not significantly enhance the assessment of oxygen saturation. Lower rates can also help to reduce noise in the signal and focus on the essential data needed for clinical decisions.

While 500Hz, 100Hz, and 20Hz could theoretically be used for SpO2 monitoring, they are not the standard or most effective sampling rates for this specific measurement, especially in a typical clinical setting.