Obstructive sleep apnoea (OSA) is a condition in which a person's sleep is disrupted with momentary periods of apnoea and hypopnoea. This occurs when there is a blockage to airflow. When this happens, the patient will snore, gasp or choke in the attempt to attain more oxygen. This results in disrupted sleep and the patient may even awake from sleep.

It has been found that a great proportion of Malaysians have habitual snoring and with the increase in obesity over the years, it is a concern that OSA may be prevalent in Malaysia.

However, it has been seen that OSA is commonly undiagnosed in patient. This poses a worry because these people can come in for surgery. Diagnosis of OSA before surgery is important in order to prepare for the complication related to OSA.

Research staff will interview and examine patients and review their charts to obtain information on patient characteristics. Patients will also be assessed using STOP-BANG Questionnaire & Epworth Sleepiness Scale.

Anaesthesia and surgery will be performed according to routine standard of care.

Drugs used during anaesthesia, postoperative analgesia and hemodynamic data will be recorded.

During their stay in hospital, patients will be followed daily, and outcomes will be recorded, until discharge. Data on medications will be recorded.

Inclusion Criteria:

• adult males and females
• age ≥ 18 years
• undergoing elective surgery ( general,regional or local anaesthesia with monitored anaesthesia care)

Exclusion Criteria:

• previous diagnosis of OSA or any sleep-related breathing disorder
• they are unwilling
• their surgery included tonsillectomy, septoplasty, uvloplasty, pharyngoplasty, tracheostomy, or prolonged mechanical ventilation

All patients over age 18 undergoing non-cardiac surgery