Purpose: Monitoring oxygen saturation (SpO2) in some patient populations during exercise is vital. The objectives of this study were to determine whether under conditions of artificial hypoperfusion pulse oximeter performance during exercise was influenced by sensor type, attachment clip reinforcement, or a low pressure arm cuff. Methods: Six different portable oximeter models were tested on study participants at rest with a control (normothermic) and experimental (hypothermic) hand. Oximeters were then tested during treadmill walking at 1 and 2 mph with the experimental hand remaining hypothermic. Electrocardiographic measurements of heart rate were also taken simultaneously. Results: There were differences in SpO2 values between oximeter pairs following cold exposure at rest for most models (5 out of 6) but during walking for only 1 model. There were also differences between oximeter and electrocardiographic heart rate measurements for some models when study participants walked on a treadmill at 1 mph (1 out of 6) and 2 mph (3 out of 6). Conclusions: Results suggest that oximeter performance is better when measuring SpO2 than heart rate. Cold-induced hypoperfusion caused inaccuracies in SpO2 measurements, which were greater at rest than during exercise. Study results also suggest that some pulse oximeters perform better when the oximeter sensor attachment clip is reinforced with an elastic band.

2016 interventions [1-3]. They allow for vital continuous monitoring of oxygenation in patients with oxygen loading impairments such as chronic obstructive pulmonary disease and heart failure. While the performance of new generation Pulse oximeters are commonly used in medical settings to non-invasively measure arterial oxyhemoglobin saturation (SpO2) and heart rate (HR) at baseline and with therapeutic Background: Measurement of oxygen saturation (SpO2) during activity and exercise is important for clinical treatment and prognostic decision-making, but oximeter error can be problematic. New generation fingertip pulse oximeters are readily available and inexpensive; therefore, their potential clinical applications are rapidly expanding. While the performance of new generation tabletop and handheld pulse oximeters has been evaluated, little information is available on the accuracy of fingertip pulse oximeters, especially during activity. Purpose: The objective of this study was to determine if new generation low cost fingertip pulse oximeters provide accurate and consistent measurements of oxygen saturation (SpO2) and heart rate (HR) during walking. Materials and Methods: Nine different fingertip oximeter models were evaluated during treadmill walking at one and two mph in healthy subjects (n = 32). Oximeter readings from both hands were simultaneously recorded and a 15 second electrocardiogram (ECG) strip was printed. Paired t-tests were used to determine differences in SpO2 measurements between oximeter pairs. An ANOVA was used to determine differences in HR measurements among oximeter pairs and ECG. Error rates were also calculated. Results: A significant difference in SpO2 values was identified between oximeter pairs for two models when subjects walked at one mph. Additionally, a significant difference in HR values existed between oximeter pairs and the ECG for two models when subjects walked at one mph. No differences were found in SpO2 or HR measurements when subjects walked at two mph. Oximeter performance was better when measuring SpO2 than HR. Also, in this study pulse oximeters performed better when subjects walked at higher versus lower exercise intensities. Conclusions: The results of this study suggest that accuracy and consistency of fingertip oximeter measurements are less than ideal during treadmill walking. Clinicians should use caution when interpreting HR values obtained with fingertip pulse oximeters during exercise.