[Is daytime sleepiness a sufficient predictor of sleep-disordered breathing during pre-anesthesia consultation?]

Sleep-disordered breathing (SDB) is associated with increased rate of perioperative complications. Daytime sleepiness is a frequent symptom of SDB. Thus, aim of the present study was to evaluate whether preoperative assessment of daytime sleepiness would be eligible for sufficient prediction of SDB.

Patients before scheduled surgery were prospectively recruited and asked to answer a standardized sleep questionnaire (Epworth Sleepiness Scale; ESS). The night before surgery, sleep polygraphy was performed and the oxygen desaturation index 4% (ODI 4%) was calculated.

Data of 363 patients (190 men and 173 women) were finally analyzed. Regarding risk assessment, 42 patients had ASA grade 1, 192 patients had ASA grade 2, 123 patients had ASA grade 3 and 6 patients had ASA grade 4. Mean Body Mass Index was 27.9 ± 5.1 kg/m2, mean age was 59.2 ± 13.3 years and mean ESS score was 5.7 ± 3.4. Clinical relevant daytime sleepiness (ESS ≥ 11) was found in 32 patients (9%). In 11 patients (34%) with ESS ≥ 11, ODI 4% ≥ 5/h was calculated whereas in 21 patients with ESS ≥ 11 (66%), ODI 4% < 5/h was found. Odds ratio between ODI 4% ≥ 5/h and ESS ≥ 11 was 0.919 (CI 0.85-0.99, p = 0.038).

In non-obese patients, daytime sleepiness is a rare event and is not associated with SDB. Thus, daytime sleepiness is not eligible for the preoperative SDB screening.