Olfactory Function and Postoperative Cognitive Dysfunction

Study Overview
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Brief Summary
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To study the correlation of POCD with olfactory function. To explore whether enhanced olfactory stimuli can reduce the risk of POCD as a preventive strategy.

Detailed Description
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Postoperative cognitive dysfunction (POCD), the most common complications of geriatric surgical patients, could contribute to long-term social dysfunction, high mortality and increased medical cost. Previous studies have suggested that impaired Olfaction was related to postoperative delirium (Nadya M. Dhanani et al, J Clin Anesth 2012; Charles H. Brown IV et al, J Am Geriatr So 2015; Min Seung Kim et al, J Neural Transm 2016). However, there is still no efficient treatment for POCD, and it also remains largely unknown whether enhanced olfactory stimuli can be used as an inventive strategy to reduce the risk of POCD.

Official Title
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Effects of Enriched Olfactory Stimuli on Postoperative Cognitive Dysfunction

Conditions
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Postoperative Cognitive Dysfunction

Intervention / Treatment
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* Behavioral: enhanced olfactory stimuli


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Keen surgery under general anesthesia; Age is greater than or equal to 65 years old; Han Nationality, mother tongue is chinese; The MMSE score: Illiteracy is greater than or equal to 17 points, primary school is greater than or equal to 20 points, higher secondary school is more than 24 points; Being able to complete the assessments without serious visual or hearing difficulty; Without serious heart, brain, liver, kidney, lung and other organs; Without serious neurological and psychiatric disorders, such as Alzheimer's disease, Parkinson's syndrome, multiple sclerosis, schizophrenia, depression, etc.; The ASA class I or II; The people signed informed consent. Exclusion Criteria: Had severe head and face disease, trauma history or history of surgery; Had a history of influenza in 3 weeks; The serious body disease and tobacco, wine and other substance abuse history; The presence of malignant tumor with shorter survival disease.

Ages Eligible for Study
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Minimum Age: 65 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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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intervention Group<br>Patients randomly assigned to intervention group will get enhanced olfactory stimuli during the perioperative period | Behavioral: enhanced olfactory stimuli<br>* Patients in intervention group will get enhanced olfactory stimuli during perioperative period (7 days before and after the surgery), by using portable scented sachets.<br>|
| No Intervention: Non-intervention Group<br>Patients randomly assigned to non-intervention group will not get any olfactory stimuli during the perioperative period | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change of cognitive function | The neuropsychological tests to assess change of cognitive function between baseline and follow-up | 1 day before surgery (baseline) and 7 days after surgery (follow-up) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change of olfactory function | The olfactory tests to assess change of olfactory function between baseline and follow-up | 1 day before surgery (baseline) and 7 days after surgery (follow-up) |