Inhalational Agents Versus Dexmedetomidine for Maintenance of General Anesthesia

Beyond Inhalational Agents: Dexmedetomidine for Maintenance of General Anesthesia - A Prospective Randomized Clinical Trial

The climate crisis and environmental pollution are escalating day by day, making the reduction of carbon footprints increasingly important both on an individual and industrial level. Inhalational anesthetic agents are widely used in daily anesthesia practice. However, some of these agents are released into the environment either unchanged or as metabolic by-products. It can take hundreds of years for these substances to be fully eliminated from nature. Therefore, there is a growing interest in identifying alternative anesthetic agents that are fully metabolized, do not produce waste, have a shorter duration of action, and pose less harm to ecosystems.

Recent clinical studies have shown that dexmedetomidine, when administered intraoperatively via infusion without a loading dose and in combination with inhalational agents, provides more stable hemodynamics and results in a shorter postoperative recovery period. Commonly used as a long-term sedative agent in intensive care units, dexmedetomidine has gained popularity in the intraoperative setting due to its stable hemodynamic profile, low incidence of withdrawal symptoms, and faster recovery.

In this study, it is aimed to demonstrate the potential use of dexmedetomidine-whose pharmacodynamic and pharmacokinetic properties are well-known to experienced anesthesiologists-as an alternative to inhalational anesthetic agents for the maintenance of anesthesia, particularly in the geriatric patient population.

Study Overview

• Status: Recruiting
• Conditions: Percutaneous Nephrolithotomy; Transurethral Resection of the Bladder; Transurethral Resection of the Prostate; Ureterorenoscopic Lithotripsy
• Intervention / Treatment: Drug: Dexmedetomidine + Remifentanil; Drug: Desflurane + Remifentanil

Detailed Description

Study Design and Setting This prospective, randomized clinical study was conducted at the Department of Anesthesiology and Reanimation, University of Health Sciences, Bakırköy Dr. Sadi Konuk Training and Research Hospital. Patient randomization was performed using a computer-based randomization tool (@randomizer).

Patient Selection A total of 150 patients over the age of 39 who provided informed consent and were scheduled for elective urological procedures at the Urology Department were enrolled in the study. The included surgeries were uretero-renoscopic lithotripsy (URS), transurethral resection of the bladder (TUR-B), percutaneous nephrolithotomy (PCNL), and transurethral resection of the prostate (TUR-P).

Anesthesia Protocol

Upon arrival to the operating room, standard monitoring was applied to all patients. Anesthesia induction and maintenance were carried out according to randomization:

Group DR: Dexmedetomidine + Remifentanil

Group IR: Desflurane + Remifentanil

Intraoperative and Postoperative Data Collection

During surgery, anesthesia depth and hemodynamic parameters were continuously monitored and recorded. At the end of the procedure, the following postoperative data were collected:

Visual Analog Scale (VAS) for pain

Richmond Agitation-Sedation Scale (RASS)

Modified Aldrete Score

The hospital unit/ward to which the patient was transferred

• Study Type: Interventional
• Enrollment (Estimated): 150
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: NALAN SAYGİ EMİR; Phone Number: 00905422363672; Email: nasaemir@hotmail.com

Study Locations

• Turkey (Türkiye)
  • Istanbul
    • Istanbul, Istanbul, Turkey (Türkiye), 34140
      • Recruiting
      • Bakirkoy dr. Sadi Konuk
      • Contact: Nalan Saygi Emir

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria

• Age ≥ 39 years
• Classified as ASA physical status II-IV
• Scheduled for elective endoscopic urological surgery (e.g., URS, TUR-B, PCNL, TUR-P)
• Scheduled for postoperative follow-up in the Post-Anesthesia Care Unit (PACU)
• Ability to provide written informed consent

Exclusion Criteria

• Requirement for conversion to open surgery during the perioperative period
• Patients who decline to participate in the study
• Presence of neuropsychiatric disorders (e.g., dementia, Parkinson's disease, epilepsy, or history of head trauma)
• History of alcohol or substance abuse
• Use of psychoactive medications
• Inability to communicate adequately for any reason

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Group DR: Dexmedetomidine + Remifentanil; The investigators will administer dexmedetomidine combined with remifentanil for anesthesia maintenance in this patient group.	Drug: Dexmedetomidine + Remifentanil; Anesthesia Protocol All patients will receive the same standardized induction regimen consisting of fentanyl (1 μg/kg), propofol (1 mg/kg), and rocuronium (0.5 mg/kg). Following induction, maintenance of general anesthesia will differ according to group allocation: In Group DR, anesthesia maintenance will be provided with dexmedetomidine administered as a continuous infusion without a loading dose, combined with remifentanil infusion. Remifentanil infusion rates will be adjusted as clinically required to maintain adequate hemodynamic stability and surgical anesthesia depth
Active Comparator: Group IR: Desflurane + Remifentanil; The investigators will administer desflurane combined with remifentanil for general anesthesia maintenance in this group.	Drug: Desflurane + Remifentanil; The investigators will administer desflurane combined with remifentanil for general anesthesia maintenance in this group.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Depth of anesthesia	Depth of anesthesia assessed using Bispectral Index (BIS) monitoring, with BIS values recorded during surgery. The target BIS range will be 40-60.	Intraoperative period

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Intraoperative hemodynamic stability	Intraoperative hemodynamic stability assessed by mean arterial pressure (MAP) and heart rate (HR) values recorded during surgery.	Intraoperative period
Quality of recovery	Quality of recovery assessed using the Quality of Recovery-15 (QoR-15) questionnaire (score range 0-150; higher scores indicate better recovery).	Postoperative day 1
Sedation Level	Sedation level assessed using the Richmond Agitation-Sedation Scale (RASS) (score range -5 to +4) where more negative scores indicate deeper sedation and positive scores indicate agitation	Post-anesthesia care unit (PACU)

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postoperative recovery time	Postoperative recovery time defined as the time to achieve an Aldrete score ≥9.	Post-anesthesia care unit (PACU)
Postoperative pain intensity	Postoperative pain intensity assessed using the Visual Analog Scale (VAS; 0-10), where higher scores indicate worse pain.	Up to 24 hours postoperatively

Collaborators and Investigators

• Sponsor: Bakirkoy Dr. Sadi Konuk Research and Training Hospital

Study record dates

Study Major Dates

• Study Start (Actual): October 1, 2024
• Primary Completion (Estimated): February 1, 2026
• Study Completion (Estimated): March 9, 2026

Study Registration Dates

• First Submitted: December 17, 2025
• First Submitted That Met QC Criteria: January 15, 2026
• First Posted (Actual): January 23, 2026

Study Record Updates

• Last Update Posted (Actual): January 23, 2026
• Last Update Submitted That Met QC Criteria: January 15, 2026
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Organic Chemicals; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Ethers; Azoles; Hydrocarbons; Acids, Acyclic; Carboxylic Acids; Imidazoles; Piperidines; Hydrocarbons, Halogenated; Hydrocarbons, Fluorinated; Propionates; Methyl Ethers; Ethyl Ethers; Remifentanil; Desflurane; Dexmedetomidine
• Other Study ID Numbers: 2023/176

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF

Drug and device information, study documents

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