Accuracy of peripheral arterial tonometry in the diagnosis of obstructive sleep apnea / Acurácia da tonometria arterial periférica no diagnóstico da apneia obstrutiva do sono

ABSTRACT INTRODUCTION: The use of handheld devices that assess peripheral arterial tonometry has emerged as an auxiliary method for assessment and diagnosis of obstructive sleep apnea syndrome. OBJECTIVE: To evaluate the accuracy of peripheral arterial tonometry in the diagnosis of obstructive sleep apnea. METHODS: Contemporary cohort cross-sectional study. Thirty patients with suspected obstructive sleep apnea underwent peripheral arterial tonometry and assisted nocturnal polysomnography concomitantly. RESULTS: The mean apnea/hypopnea index by peripheral arterial tonometry was significantly higher than that by polysomnography (p < 0.001), but the values of both sleep studies were significantly correlated (r = 0.762). There was a high correlation between variables: minimum oxygen saturation (r = 0.842,p < 0.001), oxygen saturation < 90% (r = 0.799, p < 0.001), and mean heart rate (r = 0.951, p < 0.001). Sensitivity and specificity were 60% and 96.2% (AUC: 0.727;p = 0.113), respectively, when at a threshold value of 5 events/h. In severe cases (≥30 events/h), the result was a sensitivity of 77.8% and a specificity of 86.4% (AUC: 0.846, p = 0.003). CONCLUSION: Peripheral arterial tonometry is a useful portable device for the diagnosis of obstructive sleep apnea; its accuracy is higher in moderate and severe cases.

RESUMO Introdução: A utilização de dispositivos portáteis, que avaliam a tonometria arterial periférica, surge como método adjuvante para avaliação e diagnóstico da síndrome da apneia obstrutiva do sono. Objetivo: Avaliar a acurácia da tonometria arterial periférica no diagnóstico da apneia obstrutiva do sono. Método: Estudo de coorte contemporânea com corte transversal. Trinta pacientes com suspeita de apneia obstrutiva do sono foram submetidos a tonometria arterial periférica e a polissonografia noturna assistida simultaneamente. Resultados: A média do índice de apneia/hipopneia pela tonometria arterial periféricafoi significativamente maior do que a da polissonografia (p < 0,001), porém os valores de ambos os estudos do sono foram significativamente correlacionados (r = 0,762). Houve alta correlação entre as variáveis: saturação mínima de oxigênio (r = 0,842, p < 0,001), saturação de oxigênio < 90% (r = 0,799, p < 0,001) e média de frequência cardíaca (r = 0,951, p < 0,001). A sensibilidade e especificidade foram 96,2% e 60% (AUC: 0,727, p = 0,113), respectivamente, quando limiar de 5 eventos/hora. Nos casos graves (≥ 30 eventos/hora), o resultado foi uma sensibilidade de 77,8% e uma especificidade de 86,4% (AUC: 0,846, p = 0,003). Conclusão: A tonometria arterial periférica é um dispositivo portátil útil no diagnóstico da apneia obstrutiva do sono e sua acurácia é maior nos casos moderados e graves.

Accuracy of peripheral arterial tonometry in the diagnosis of obstructive sleep apnea.

INTRODUCTION: The use of handheld devices that assess peripheral arterial tonometry has emerged as an auxiliary method for assessment and diagnosis of obstructive sleep apnea syndrome. OBJECTIVE: To evaluate the accuracy of peripheral arterial tonometry in the diagnosis of obstructive sleep apnea. METHODS: Contemporary cohort cross-sectional study. Thirty patients with suspected obstructive sleep apnea underwent peripheral arterial tonometry and assisted nocturnal polysomnography concomitantly. RESULTS: The mean apnea/hypopnea index by peripheral arterial tonometry was significantly higher than that by polysomnography (p<0.001), but the values of both sleep studies were significantly correlated (r=0.762). There was a high correlation between variables: minimum oxygen saturation (r=0.842, p<0.001), oxygen saturation<90% (r=0.799, p<0.001), and mean heart rate (r=0.951, p<0.001). Sensitivity and specificity were 60% and 96.2% (AUC: 0.727; p=0.113), respectively, when at a threshold value of 5 events/h. In severe cases (≥30 events/h), the result was a sensitivity of 77.8% and a specificity of 86.4% (AUC: 0.846, p=0.003). CONCLUSION: Peripheral arterial tonometry is a useful portable device for the diagnosis of obstructive sleep apnea; its accuracy is higher in moderate and severe cases.