The Effect of Intraoperative Esketamine Infusion on Pruritus in Elderly Surgical Patients

The Effect of Intraoperative Esketamine Infusion on Pruritus in Elderly Surgical Patients: A Single-Center Randomized Controlled Trial

To explore the effect of intraoperative esketamine on pruritus in elderly patients undergoing elective general anesthesia for knee replacement surgery

Study Overview

• Status: Not yet recruiting
• Conditions: Senile Pruritus
• Intervention / Treatment: Drug: Normal Saline; Drug: Esketamine

Detailed Description

Pruritus (itching) is one of the most common clinical conditions in the elderly population. Its etiology is complex, and the prevalence gradually increases with age. Pruritus in the elderly not only imposes a significant disease burden but also severely affects their sleep quality and daily life. This chronic, persistent itching often disrupts the skin barrier function, easily creating a vicious itch-scratch cycle, which leads to multiple damages to the patient's quality of life.Esketamine is the right-handed isomer of ketamine and is a non-competitive N-methyHD-aspartate (NMDA) receptor antagonist. It has the effects of rapid pain relief,rapid antidepressant action, sedation, and improvement of sleep. Relevant studies have shown that the NMDA receptor may play an importantrole in the transmission of non-histaminergic itching. However, there is still a lack of reports on whether it can relieve pruritus symptoms in elderly patients. This experiment intends to investigate the effect of intraoperative esketamine infusion on skin pruritus in elderly surgical patients.

• Study Type: Interventional
• Enrollment (Estimated): 200
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Guolin Wang; Phone Number: 15822855556; Email: wangguolinhad@hotmail.com

Study Locations

• China
  • Tianjin, China, 300052
    • Tianjin Medical University General Hospital
    • Contact: Guolin Wang; Phone Number: +8618604755166; Email: wangguolinhad@hotmail.com

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

1. Meet the diagnostic criteria for senile pruritus:

   1. Aged ≥ 65 years old;
   2. Presenting with only skin pruritus without obvious primary skin lesions, with or without scratch-induced skin lesions;
   3. Daily or nearly daily pruritus lasting for more than 6 weeks.
2. Patients undergoing elective general anesthesia for orthopedic knee arthroplasty.
3. Patients aged ≥ 65 years old, with ASA physical status classification Ⅰ-Ⅲ; BMI ranging from 18 to 30 kg/m², with no restriction on gender.
4. Patients have fully understood the nature of this study, are capable of understanding and completing evaluation scales preoperatively, voluntarily participate in this trial, and sign the informed consent form.

Exclusion Criteria:

1. Those who are allergic to the pharmaceutical ingredients of this study or have an allergic constitution;
2. Those with a history of allergy to general anesthetics, opioids, or non-steroidal anti-inflammatory drugs;
3. Those with severe cognitive impairment, a history of neurological diseases, chronic pain, drug addiction, alcoholism, long-term opioid use, or administration of opioids within 48 hours before surgery;
4. Patients with ASA physical status classification Grade IV-V;
5. Those with severe coronary heart disease/arrhythmia/cardiac insufficiency, bronchial asthma, severe hypertension, severe hematopoietic system dysfunction, severe abnormal liver and kidney function, or significant electrolyte disorders;
6. Those with a history of gastrointestinal diseases (peptic ulcer, Crohn's disease, ulcerative colitis);
7. Those with respiratory insufficiency or respiratory failure;
8. Those with BMI < 18 kg/m² or BMI > 30 kg/m²;
9. Those with poor compliance who cannot complete the trial in accordance with the research protocol;
10. Those who have participated in other clinical drug trials within the past 4 weeks;
11. Those deemed unsuitable for enrollment by the researchers for any reason. -

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Elderly patients with senile pruritus receive normal saline.; An equal volume of normal saline is intravenously administered 30 minutes prior to the completion of the operation.	Drug: Normal Saline; An equal volume of normal saline is intravenously administered 30 minutes prior to the completion of the operation.
Active Comparator: Elderly patients with pruritus receive esketamine at a dose of 0.2 mg/kg.; Esketamine 0.2 mg/kg is intravenously administered 30 minutes prior to the completion of the operation.	Drug: Esketamine; Esketamine 0.2 mg/kg is intravenously administered 30 minutes prior to the completion of the operation.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
5D-IS score at 24 hours after surgery	The duration, severity, outcome trend, life impairment and pruritus site (5-D) were used to evaluate the patient's pruritus.Each dimension was scored from 1 to 5, with a total score ranging from 5 to 25. The higher the score, the more severe the itching.	24 hours after surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
5D-IS score at 48 hours,72 hours and the seventh day after surgery	The duration, severity, outcome trend, life impairment and pruritus site (5-D) were used to evaluate the patient's pruritus.Each dimension was scored from 1 to 5, with a total score ranging from 5 to 25. The higher the score, the more severe the itching.	48 hours,72 hours and the seventh day after surgery
The incidence of pruritus on the 24 hours after surgery	The 5D-IS score was completed by the patient 24 hours after the operation. The investigators recorded this score as a statistical indicator.	24 hours after surgery
NRS pruritus score at 24 hours,48 hours and 72 hours after surgery	The patient evaluated the intensiy of prurtus wth 11 numbers ranging from 0 to 10,and the higher the number, the more severe the condition. The higher the number, the more severe the itching. 0: No sensation. 1-3: Mild itching. 4-6 Moderate itching 7-9: Severe itching. 10; Extrermely severe itching.	24 hours,48 hours and 72 hours after surgery
Pain Score (NRS)	The pain score at rest or after movement was evaluated by pain 11-point numerical rating scale (NRS): 0= no pain, 10 = greatest imaginable pain.	1 hours, 24 hours, 48 hours, 72 hours after the surgery
The incidence of postoperative sleep disturbance on the first. second and third postoperative nights	The patient completed the Sleep Quality Scale (AlS, Athens Insomnia Scale) one day before the surgery, There are a totat of 8 items in the AlS,with the score ranging from 0 to 24. A total score of 6 or above indicates a diagnosis of insomnia. We asked the patients to fill out this questionnaire after the first,second and third postoperative nights to evaluate the changes in sleep quality. The investigators recorded AlS scores as statistical indicators.	the first,second and third nights after surgery
Montreal Cognitive Assessment (MoCA)	The Montreal Cognitive Assessment consists of 7 items, which evaluate visuospatial and executive function (5 points), naming (3 points), attention (6 points), language (3 points), abstract thinking (2 points), delayed recall (5 points), and orientation (6 points) respectively. A total score of ≥26 points indicates basically normal cognitive function; a total score of <25 points suggests cognitive decline.	24 hours, 48 hours, 72 hours after the surgery
Confusion Assessment Method (CAM)	Confusion Assessment Method CAM is assessed based on four core features. Feature 1: Acute onset or fluctuating course; Feature 2: Inattention; Feature 3: Disorganized thinking; Feature 4: Altered level of consciousness. The diagnosis of delirium requires a positive result for Feature 1 + a positive result for Feature 2 + a positive result for either Feature 3 or Feature 4.	24 hours, 48 hours, 72 hours after the surgery

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Intraoperative Anesthesia Information	Duration of anesthesia (minutes)	Perioperative period
Intraoperative Vital Signs	Intraoperative average heart rate	Perioperative period
Adverse Event	All kinds of adverse events(nausea, vomiting, respiratory depression, headache, dizziness, chills, delayed recovery from anesthesia) occurred in patients were recorded.	1 hour, 24 hours, 48 hours and 72 hours after surgery
Intraoperative Anesthesia Information	Duration of surgery (minutes)	Perioperative period
Intraoperative Anesthesia Information	Intraoperative dosage of Sufentanil （μg）	Perioperative period
Intraoperative Anesthesia Information	Intraoperative dosage of Remifentani (mg)	Perioperative period
Intraoperative Vital Signs	intraoperative average blood oxygen saturation	Perioperative period
Intraoperative Vital Signs	Mean Arterial Pressure（MAP）	Perioperative period

Collaborators and Investigators

• Sponsor: Tianjin Medical University General Hospital
• Investigators: Study Director: Guolin Wang, Tianjin Medical University General Hospital

Study record dates

Study Major Dates

• Study Start (Estimated): May 15, 2026
• Primary Completion (Estimated): June 20, 2027
• Study Completion (Estimated): September 30, 2027

Study Registration Dates

• First Submitted: May 7, 2026
• First Submitted That Met QC Criteria: May 18, 2026
• First Posted (Actual): May 19, 2026

Study Record Updates

• Last Update Posted (Actual): May 19, 2026
• Last Update Submitted That Met QC Criteria: May 18, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: esketamine; pruritus
• Additional Relevant MeSH Terms: Skin Manifestations; Skin Diseases; Pathological Conditions, Signs and Symptoms; Skin and Connective Tissue Diseases; Signs and Symptoms; Pruritus; Pharmaceutical Preparations; Crystalloid Solutions; Isotonic Solutions; Solutions; Esketamine; Saline Solution
• Other Study ID Numbers: IRB2025-YX-498-01

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