Study objective: To examine the prevalence of risk of sleep apnea in patients undergoing elective surgery by using the Berlin Questionnaire.
Design: Survey instrument.
Settings: Preoperative assessment clinic.
Patients: 305 surgical ASA physical status I, II, III, and IV patients.
Interventions: Patients were screened with the Berlin questionnaire for obstructive sleep apnea. For patients deemed at high risk of sleep apnea by the Berlin questionnaire, a letter was sent to their family physician requesting referral of patient to have an overnight polysomnography test for the diagnosis of obstructive sleep apnea.
Measurements: The number of patients identified by the Berlin questionnaire as being at high risk of obstructive sleep apnea was identified. The number of patients with a history of obstructive sleep apnea and those newly confirmed by polysomnography were also identified.
Main results: The Berlin questionnaire identified 24% (73/305) of patients as being at high risk of sleep apnea (95% confidence interval, 19%-29%). Thirteen patients were confirmed to have obstructive sleep apnea, resulting in a frequency of 4.2%; 9 patients had a history of obstructive sleep apnea, and 5 patients were identified by polysomnography.
Conclusions: The Berlin questionnaire correctly identified all patients previously diagnosed with sleep apnea as being at high risk.