Objective: To determine if enamel nail polish interferes with pulse oximetry.
Design: Laboratory investigation.
Participants: 12 healthy nonsmoking volunteers.
Methods: Spectrophotometry was performed on polystyrene cuvettes painted with 3 uniform layers of nail polish enamel in triplicate. Absorbances were compared at 660 and 940 nm for 10 colors across the visible spectrum and documented by the Institute of Electrical and Electronic Engineers color code against Pantone matches on a color scanner. Colors were then selected that had the greatest A660-A940 difference and pulse oximetry (Nellcor N-209A. Pleasanton , CA) was performed on nails painted with these colors on 12 subjects using an unpainted digit as a control.
Results: When tested by the oximeter, there were no SpO2 differences detected between nail polish colors, nor were there any differences between the painted and the unpainted control digits across subjects (F = 0.51, ANOVA; p = 0.67). Blue (B), green (G), and lime green (G') possessed the largest A660-A940 difference and potentially could interfere with pulse oximetry but did not do so in the clinical model.
Conclusion: Enamel finger nail polish pigments do not interfere with pulse oximetry as previously reported, the A660-A940 difference must be greater than 1.88 +/- 0.23 SD AU in order to affect pulse oximetry.