RESUMO
Although essential before surgery, in-lab lysomnography and in-hospital sleep studies cannot be done indiscriminately for all patients with potential diagnosis of obstructive sleep apnea [OSA]. Some clinical parameters may be used to select patients for these studies, thus increasing their cost-effectiveness. Studying the relationship of body mass index [BMI], modified Mallampati index [MMI], tonsil size and thyroid-mental distance [TMD] to the grade of OSA. Tertiary referral hospital. Thirty consecutive patients [20 men and 10 women] in the age range of 30 to 60 years with snoring for at least 3 months and observed cessation of respiration during sleep were included. SAM[TM] monitor [Intercare Technologies, Inc, Milwaukee, WI] was used for an eight-hour in-hospital sleep study. There was a statistically significant relationship between BMI, MMI and tonsil grade and the grade of OSA [p=0.01, p=0.036, p=0.05 respectively]. No statistically significant relationship was found between TMD and grade of OSA [p=0.456]. In patients with potential diagnosis of OSA, BMI, MMI and tonsil size grade are helpful in selecting patients for in-hospital sleep studies