This is a prospective, interventional cohort study of drug-induced sleep endoscopy (DISE). The goal is to evaluate the upper airway in a cohort of patients with obstructive sleep apnea hypopnea syndrome (OSAHS) diagnosed in a prior polysomnography.

This study correlates the sedation level measured by entropy during DISE using propofol via a TCI pump with the local obstruction patterns of the upper airway according to the VOTE classification.

As OSAHS is a widespread disease and the DISE procedure has become a common tool for diagnosis and evaluation of further treatment, a growing number of research articles deal with this topic. These articles are available through pubmed.

Inclusion Criteria:

• documented sleep apnea Syndrome with an AHI > 5 diagnosed by polysomnography

Exclusion Criteria:

• active infection
• performed oral, head or neck surgery, pregnancy,
• ASA classification III or higher,
• chronic use of alcohol, sedatives or illicit drugs and chronic
• obstructive pulmonary disease.