Background: Pulse oximetry is a noninvasive method to measure the saturation of peripheral oxyhaemoglobin (SpO2). It's usually used in emergency, intensive care and operating room units. Pulse oximeter readings have limited accuracy in the presence of methemoglobin, carboxyhemoglobin, anaemia, peripheral vasoconstriction, nail polish, fluorescent light, and motion. Objectives: To evaluate the interferences of the color of nail polishes and time on SpO2 in healthy individuals. Methods: Sixty-one healthy female volunteers, ages ranging from 18 to 32 years. The nail polish colors used to evaluate SpO2 were: base coat on the little finger, light pink on the ring finger, sparkling light pink on the medium finger and red on the thumb. The index finger was used as control and thus, did not receive nail polish. The time for each color was evaluated every minute until 5 minutes were completed. Results: When the SpO2 measurement was compared with the control, the base coat (p = 0.56), light pink (p = 0.56) and sparkling light pink (p = 0.37) colors didn't present statistically significant differences. Only the red presented a significant variation (p < 0,001), however it was within normal parameters. SpO2 didn't vary significantly with time. Conclusion: Despite the difference found with the red color, all the SpO2 values achieved were inside the normal range for a healthy individual. Pulse oximeter readings are not significantly affected by the color of nail polish in relation to time.

Keywords: Nail polish. Oxygen saturation. Pulse oximetry.

Repeated dosis of inhaled β2-agonists have been used in the treatment of acute asthma. The effect of added ipratropium bromide (IB) to β2-agonist is controversial in adults. Objective: To evaluate if addition of IB to fenoterol, in repeated doses, induces a greater bronchodilation, a greater reversion of the attack, and discharge from emergency unit in adults with acute severe asthma. Setting: Pneumology Emergency Department, Unifesp-Hospital São Paulo, in the period from July 1995 to February 1997. Type of study: Open, randomized and parallel study. Discharge from the hospital: FEV1 and PEF ≥ 60% of the predicted value. Methods: 120 patients with FEV1 and PEF ≤ 50% of the predicted value were divided into two groups (N = 60): fenoterol (F) and ipratropium bromide + fenoterol (IBF). Each group received inhalation treatment through a metered-dose inhaler (MDI) attached to a holding chamber, administered at 30-minute interval, for a total of three treatments. In the group F four puffs of fenoterol (400 μg) were administered, and in the IBF group, 160 μg of BI and 400 μg of fenoterol (four puffs). Results: The patients did not differ from basal PEF (F = 36 ± 7% vs IBF = 35 ± 9% predicted) and basal FEV1 (F = 33 ± 9% vs IBF = 32 ± 9% predicted). Thirty-two patients of group F and 33 of group IBF were discharged from hospital after the inhalation treatment. The final FEV1 and PEF after inhalation treatments were F = 60 ± 13% vs IBF = 61 ± 11% e F = 74 ± 18% vs IBF = 77 ± 13% (NS). Conclusion: The addition of ipratropium bromide to fenoterol results in insignificant functional effect and without clinical impact in the treatment of acute asthma in adults.

Keywords: Fenoterol. Ipratropium. Status asthmaticus. Respiratory therapy.