Effect of Preoperative Olfactory Training on Postoperative Delirium in the Elderly Undergoing Orthopedic Surgeries

Preoperative Olfactory Training Reduces the Incidence of Postoperative Delirium in Elderly Patients Undergoingorthopedic Surgeries: a Prospective Randomized Controlled Clinical Study

To observe whether preoperative olfactory training can reduces the incidence of postoperative delirium in elderly patients undergoing orthopedic surgeries, a prospective randomized controlled study method will be used in this study.

Study Overview

• Status: Not yet recruiting
• Conditions: Postoperative Delirium; Preoperative Olfactory Training
• Intervention / Treatment: Behavioral: olfactory training

Detailed Description

450 elderly patients undergoing orthopedic surgeries (hip or knee replacement and laminectomy) under general anesthesia or combined spinal epidural anesthesia will be selected. They will be randomly divided into control group and olfactory training group.The olfactory training group was performed 24-48h before surgery used phenylethyl alcohol (rose), phytol (press tree), citronella (lemon), eugenol (clove) 4 kinds of smell，twice a day for three days. The general condition, operation, anesthesia and hospitalization related data of the patients will be recorded.

Outcome Measures： Incidence of postoperative delirium: The 3D-CAM scores of the control group and the olfactory training group were evaluated within 1-5 days after operation.

Degree of delirium：The MDAS of the control group and the olfactory training group were evaluated within 1-5 days after operation.

Pain：The VAS of the control group and the olfactory training group were evaluated within 1-5 days after operation.

Olfactory function：The TDI scores of the control group and the olfactory training group were evaluated in 3 days before operation and 48h after operation.

Cognitive function：The MoCA scores of the control group and the olfactory training group were evaluated in postoperative 5-7 days.

Markers: Delirium related markers and inflammatory factors in bloods was detected before surgery and after anesthesia. Delirium related markers and inflammatory factors in cerebrospinal fluid was detected after spinal puncture.

Subgroup analysis: patients were divided into delirium group and non-delirium group according to whether delirium occurred, and the data of the two groups were compared, including preoperative and postoperative olfactory function TDI scores, preoperative and postoperative VAS scores, nutritional scores, activity scores, and frailty index, Carlson comorbidity index, depression, anxiety state, sleep disturbance, etc., to screen risk factors.

• Study Type: Interventional
• Enrollment (Estimated): 450
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Yanni Fu; Phone Number: 81332283; Email: fuyanni@126.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Patients undergoingorthopedic surgeries (hip or knee replacement and laminectomy) under general anesthesia or combined spinal-epidural anesthesia:
2. 65 years old ≤ age ≤ 90 years old, gender is not limited, ASA classification ≤ class III:
3. There is no recent history of surgery, and the operation time is ≥ 2 hours.
4. Able to communicate normally, able to cooperate and complete the cognitive function test. MMSE score >17.
5. Patients and their families are aware of and willing to participate.

Exclusion Criteria:

1. emergency surgery;
2. People with brain diseases or history of brain diseases such as cerebral infarction, stroke, etc.:
3. Have a history of neurological and psychological diseases, including Alzheimer's disease, Parkinson's, psychosis, etc.:
4. Illiteracy, severe hearing or visual impairment;
5. Those who have taken psychotropic drugs or abused psychotropic drugs within one month:
6. Sinusitis, previous nasal surgery history, nasal congestion, upper respiratory tract infection in the past two weeks, previously diagnosed rhinitis and other diseases that may affect olfactory function.
7. Patients who are allergic to pollen
8. Patients who cannot cooperate or refuse to sign informed consent

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: Control group; The control group conducts standard preoperative preparation
Experimental: olfactory training group; The olfactory training group was performed 24-48h before surgery used phenylethyl alcohol (rose), phytol (press tree), citronella (lemon), eugenol (clove) 4 kinds of smell，twice a day for three days.	Behavioral: olfactory training; In this group, patients were performed 24-48h before surgery used phenylethyl alcohol (rose), phytol (press tree), citronella (lemon), eugenol (clove) 4 kinds of smell，twice a day for three days.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of postoperative delirium	The 3D-CAM scores	Postoperative 1-5 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Degree of delirium	Memorial delirium assessment scale(MDSA)	Postoperative 1-5 days
Olfactory function	The Sniffin' Sticks test involves testing odor for threshold and discrimination whilst blind folded and secondly odor identification. The sum of four odors responses ranges from 0-16. The sum of total score from odor Threshold, Discrimination and Identification (TDI) is a maximum of 48 points. The total score is graded as; normosmia equals or over 30.5 points, hyposmia 16.5-30 points and anosmia less than 16.5 points.	postoperative 48h compared to preoperative 72h
Cognitive function	Total score of the Montreal Cognitive Assessment (MoCA).	postoperative 5-7 days
Postoperative pain	Post-operative pain, measured in visual analogue scale (VAS),0:no pian, 10:worst pain.	Postoperative 1-5 days
Delirium related markers and inflammatory factors in bloods	These markers include:IL-6, IL-8, IL-10, TNF-α, IL-1β, CRP, N-terminal BNP, albumin, NSE, S-100B, Aβ-42 and T-tau, P-tau, S-100β	immediate post-anesthesia compared to pre-operation
Delirium related markers and inflammatory factors in cerebrospinal fluid	These markers include:IL-6, IL-8, IL-10, TNF-α, IL-1β, albumin, NSE, S-100B, Aβ-42 and T-tau, P-tau, S-100β	immediate post-anesthesia compared to pre-operation

Collaborators and Investigators

• Sponsor: Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University

Study record dates

Study Major Dates

• Study Start (Estimated): July 1, 2023
• Primary Completion (Estimated): July 1, 2025
• Study Completion (Estimated): January 1, 2026

Study Registration Dates

• First Submitted: May 29, 2023
• First Submitted That Met QC Criteria: June 8, 2023
• First Posted (Estimated): June 16, 2023

Study Record Updates

• Last Update Posted (Estimated): June 16, 2023
• Last Update Submitted That Met QC Criteria: June 8, 2023
• Last Verified: May 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Mental Disorders; Pathologic Processes; Nervous System Diseases; Postoperative Complications; Neurologic Manifestations; Confusion; Neurobehavioral Manifestations; Neurocognitive Disorders; Delirium; Emergence Delirium
• Other Study ID Numbers: SYSKY-2023-137-02

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No