Effects of Perioperative Operating Room Environment on Postoperative Delirium

Study Overview
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Brief Summary
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Thi investigators aims to observe the impact of perioperative body temperature and the noise of operating room on postoperative delirium for elderly patients undergoing abdominal surgery. And based on this study the investigators aimed to explore the potential risk factors of postoperative delirium for elderly patients undergoing abdominal surgery.

Official Title
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Effects of Perioperative Operating Room Environment on Postoperative Delirium in Elderly Patients With Abdominal Surgery : A Prospective Cohort Study

Conditions
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Postoperative Delirium

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 65-90 years old; ASA I-III; Patients who plan to undergo elective abdominal surgery under general anesthesia; Volunteer to participate in this study and sign informed consent. Exclusion Criteria: Patients with known mental illness or lack of communication or cognitive impairment before operation; Severe vision, hearing, language impairment or other reasons unable to communicate with visitors; Severe dysfunction of important organs such as heart, brain, lung, liver, kidney, etc.; Long-term use of sedatives, antidepressants or alcoholism; Patients with severe postoperative complications and admitted to intensive care unit; Patients who refused or failed to complete the cognitive function test. Patients who could not cooperate with the study for any other reason.

Ages Eligible for Study
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Minimum Age: 65 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative delirium during the 3 days-follow-up after anesthetic resuscitation | Postoperative delirium was tested with 3 minutes-Confusion Assessment Method or Confusion Assessment Method-intensive care unit (0-4, higher scores means worse outcome). The patient is determined to be postoperative delirium (ie, Confusion Assessment Method positive) if he/she fall ill quickly with confusion disorder, and with mental disorder or consciousness disorder. | From ending of the surgery to 3 days after anesthetic resuscitation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative delirium in the postanesthesia care unit | Postoperative delirium was tested with 3 minutes-Confusion Assessment Method (0-4, higher scores means worse outcome). The patient is determined to be postoperative delirium (ie, Confusion Assessment Method positive) if he/she fall ill quickly with confusion disorder, and with mental disorder or consciousness disorder. | From ending of the surgery to the time when discharge from postanesthesia care unit, an average of 30 minutes | 
| Hospital stay | Time duration of the patients' stay in hospital | From the ending of the surgery to hospital discharge, with means of about 7 days | 
| Postoperative complication | The number of patients who having complication during the hospitalization | From the ending of the surgery to hospital discharge, with means of about 7 days |