Testing Two Doses of Nebulized Ketamine for Postoperative Sore Throat

NCT07746115 | Not Yet Recruiting

• 1 other identifier: 1119/6/25
• Study Type: interventional
• Target: 195
• Locations: 0 countries
• Sites: N/A

Brief Summary

Postoperative sore throat (POST) is one of the most common complications following general anesthesia with endotracheal intubation, affecting patient comfort, delaying recovery, and reducing overall satisfaction with perioperative care. Although POST is usually self-limiting, its high incidence makes it an important target for preventive interventions. Nebulized ketamine has emerged as a promising non-invasive strategy for reducing POST because of its local analgesic and anti-inflammatory effects mediated through N-methyl-D-aspartate (NMDA) receptor antagonism. Previous randomized trials and systematic reviews have demonstrated that nebulized ketamine can reduce both the incidence and severity of POST compared with placebo. However, most published studies have evaluated a single 50-mg dose, and the minimum effective dose remains uncertain. This prospective, randomized, placebo-controlled, double-blind clinical trial aims to compare the efficacy and safety of two preoperative doses of nebulized ketamine (25 mg and 50 mg) with placebo in adult patients undergoing elective surgery under general anesthesia with endotracheal intubation. Participants aged 18-65 years with American Society of Anesthesiologists (ASA) physical status I or II will be randomly assigned in a 1:1:1 ratio to receive nebulized ketamine 25 mg, nebulized ketamine 50 mg, or nebulized normal saline 15 minutes before induction of anesthesia. The primary outcome is the incidence of postoperative sore throat assessed at 2, 4, 6, 12, and 24 hours after surgery using a standardized four-point grading scale. Secondary outcomes include the severity of POST, postoperative pain intensity measured using the Visual Analog Scale (VAS), patient satisfaction, need for rescue analgesia, sedation assessed using the Ramsay Sedation Scale, and the incidence of adverse effects, including nausea, dizziness, and hallucinations. The study hypothesizes that a lower dose of nebulized ketamine (25 mg) will provide comparable protection against postoperative sore throat to the conventional 50-mg dose while minimizing dose-related adverse effects. Identifying the minimum effective dose may improve the safety profile, optimize perioperative patient comfort, and support evidence-based recommendations for preventing postoperative sore throat after endotracheal intubation.

Conditions

Postoperative Sore Throat

Outcome Measures

Primary Outcomes (1)

• Incidence of Postoperative Sore Throat (POST)

  The proportion of participants experiencing postoperative sore throat following endotracheal intubation, assessed using a standardized 4-point grading scale: 0 = no sore throat; 1 = mild (complains only when asked); 2 = moderate (complains spontaneously); 3 = severe (hoarseness or pain interfering with activities).

  At 2, 4, 6, 12, and 24 hours after extubation.

Secondary Outcomes (6)

• Severity of Postoperative Sore Throat

  At 2, 4, 6, 12, and 24 hours after extubation.

• Postoperative Pain Intensity

  At 2, 4, 6, 12, and 24 hours after extubation.

• Patient Satisfaction

  At 24 hours after surgery.

• Need for Rescue Analgesia

  Within the first 24 hours after extubation.

• Sedation Level

  At 2, 4, 6, and 12 hours after extubation.

Study Arms (3)

Nebulized Ketamine 50 mg

EXPERIMENTAL

Drug: Placebo Comparator; Drug: Ketamine 50 MG/ML; Drug: Ketamine 25 mg

Nebulized Ketamine 25 mg

EXPERIMENTAL

Drug: Placebo Comparator; Drug: Ketamine 50 MG/ML; Drug: Ketamine 25 mg

Nebulized Placebo (Normal Saline)

PLACEBO COMPARATOR

Drug: Placebo Comparator; Drug: Ketamine 50 MG/ML; Drug: Ketamine 25 mg

Interventions

Placebo Comparator DRUG

Participants receive 5 mL of nebulized 0.9% sodium chloride (normal saline) administered 15 minutes before induction of general anesthesia using the same nebulizer and oxygen flow rate (6-8 L/min) as the active treatment to maintain blinding.

Nebulized Ketamine 25 mg; Nebulized Ketamine 50 mg; Nebulized Placebo (Normal Saline)

Ketamine 50 MG/ML DRUG

Participants receive 50 mg of nebulized ketamine diluted to a total volume of 5 mL, administered over approximately 15 minutes beginning 15 minutes before induction of general anesthesia.

Nebulized Ketamine 25 mg; Nebulized Ketamine 50 mg; Nebulized Placebo (Normal Saline)

Ketamine 25 mg DRUG

Participants receive 25 mg of nebulized ketamine diluted to a total volume of 5 mL, administered over approximately 15 minutes beginning 15 minutes before induction of general anesthesia.

Nebulized Ketamine 25 mg; Nebulized Ketamine 50 mg; Nebulized Placebo (Normal Saline)

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adults aged 18 to 65 years. American Society of Anesthesiologists (ASA) physical status I or II. Scheduled for elective surgery under general anesthesia requiring endotracheal intubation.
• Able to provide written informed consent. Willing to comply with all study procedures and follow-up assessments.

You may not qualify if:

• Known hypersensitivity or allergy to ketamine. Pre-existing sore throat, hoarseness, or significant upper airway pathology. Current upper respiratory tract infection. Anticipated difficult airway or more than one intubation attempt. Surgery involving the upper airway, oral cavity, pharynx, larynx, or maxillofacial region.
• Severe cardiovascular disease or uncontrolled hypertension. Severe respiratory disease. Pregnancy or breastfeeding. History of psychiatric illness or psychosis. Chronic opioid use or regular use of analgesic or anti-inflammatory medications.
• Inability to communicate postoperative symptoms or complete study assessments.

Sponsors & Collaborators

• Aswan University Hospital: lead

MeSH Terms

Interventions

Ketamine

Intervention Hierarchy (Ancestors)

Cyclohexanes; Cycloparaffins; Hydrocarbons, Alicyclic; Hydrocarbons, Cyclic; Hydrocarbons; Organic Chemicals

Study Officials

• Ayman M Eldemrdash

  Aswan Faculty of medicine

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Huda Mohammed Hussien Ahmed, M.B.B.Ch.

CONTACT

+20 10037253; hoda01545@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Resident in Anesthesiology, Surgical Intensive Care, and Pain Medicine

Study Record Dates

• First Submitted: July 30, 2026
• First Posted: August 4, 2026
• Study Start (Estimated): August 15, 2026
• Primary Completion (Estimated): February 15, 2027
• Study Completion (Estimated): March 1, 2027
• Last Updated: August 4, 2026

Record last verified: 2026-07

Data Sharing

• IPD Sharing: Will not share