What is a common limitation of standard pulse oximeters?

Standard pulse oximeters are widely used to measure arterial oxygen saturation and heart rate through non-invasive means. However, these devices have common limitations that can affect their performance.

One significant limitation is their tendency to provide inaccurate readings during high motion. Patients who are moving, whether due to agitation, exercise, or tremors, can cause the oximeter to pick up erratic signals, leading to unreliable measurements. This is particularly problematic in emergency settings where accurate oxygen saturation levels are crucial.

Another important limitation is how pulse oximeters perform at low saturation levels. These devices may struggle to give reliable readings when blood oxygen saturation falls below normal ranges, typically around 90-92%. At lower saturation levels, the light absorption characteristics alter in such a way that the accuracy of the readings can decline, which poses a risk when assessing patients in critical condition.

Thus, acknowledging both the inaccuracies during high motion and the unreliable results at low saturation thresholds gives a comprehensive understanding of the limitations inherent to standard pulse oximeters.