The importance of good sleep has been gaining interest in critically ill patients as poor sleep is associated with increased rates of delirium, non-invasive ventilation failure and stress to the patient.

The use of earplugs and eye masks has been shown to result in longer sleep time and better sleep quality. The primary outcome of this randomized control trial is to evaluate if the use of eye masks and earplugs in patients undergoing major abdominal surgery will lead to improved sleep quality. Secondary outcomes include the level of noise intensity in the various monitored units, incidence of delirium, nursing demand, length of hospitalization and anaesthetic techniques. With these findings, we hope to be able to improve patients' overall satisfaction with the healthcare received.

The importance of good sleep has been gaining interest in critically ill patients as poor sleep has been found to be associated with increased rates of delirium, non-invasive ventilation failure, and may serve as a stressor to patients. The use of earplugs and eye masks to improve sleep quality has been described in the critically ill patient population and outcomes have suggested that such interventions have resulted in longer sleep time and Rapid Eye Movement sleep, shorter sleep onset latency and less awakenings, with an enhanced perceived sleep quality. In the post-anaesthesia care unit, these interventions have also led to significantly preserved sleep quality in patients. The primary outcome of this randomized control trial is to evaluate if the use of eye masks and earplugs in patients undergoing major abdominal surgery, and who will be admitted to a monitored unit postoperatively, will lead to improved sleep quality. Secondary outcomes evaluated include the level of noise intensity in the various monitored units (Intensive Care Unit/Intermediate Care Area/High Dependency Ward), incidence of delirium, nursing demand, length of hospitalization and anaesthetic techniques. With these findings, we hope to be able to improve patients' overall satisfaction with the healthcare received.

Inclusion Criteria:

• All patients who are 21 years old and above, undergoing elective major abdominal surgery in Singapore General Hospital, and who are anticipated to require a monitored bed postoperatively will be identified via Operating Theatre Management system the day before surgery. Postoperatively, these patients must have a Glasgow Coma Scale of at least 10, able to obey verbal commands and stay in a monitored unit postoperatively (Intensive Care Unit/Intermediate Care Area/High Dependency).

Exclusion Criteria:

• Patients who have known hearing impairment, dementia, confusion, delirium or with a tracheostomy will be excluded.

Blinded assessors will review the patients for 3 days post-operatively and assess sleep quality using the Richard-Campbell sleep questionnaire.