Comparison of IV Dexmedetomidine Versus Clonidine Versus no Alpha 2 Agonist on Emergency Delirium, PACU Length of Stay and Time to Hospital Discharge in Children Undergoing (Adeno)Tonsillectomy: a Prospective Observational Study (CLONIDEX)

November 2, 2026 updated by: Hélène De Cuyper, Universitair Ziekenhuis Brussel

Comparison of Intravenously Administered Dexmedetomidine Versus Clonidine Versus No Alpha-2 Agonist on Emergence Delirium, PACU Length of Stay, and Time to Hospital Discharge in Children Undergoing (Adeno)Tonsillectomy: A Prospective Observational Study

Emergence delirium (ED) is a frequent complication in children undergoing general anesthesia, particularly following ENT procedures such as adenotonsillectomy. Alpha-2 adrenergic agonists, such as clonidine and dexmedetomidine, are commonly used in pediatric anesthesia for their sedative, analgesic, and ED-reducing properties.The purpose of this prospective observational study (CLONIDEX) is to evaluate and compare the occurrence of emergence delirium, Post-Anesthesia Care Unit (PACU) length of stay, and overall time to hospital discharge in pediatric patients undergoing (adeno)tonsillectomy with or without placement of myringotomy tubes who receive intravenous dexmedetomidine, intravenous clonidine, or no alpha-2 agonist as part of their standard anesthetic care.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Not yet recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Background:

Emergence delirium (ED) in pediatric patients leads to increased post-anesthesia care unit (PACU) complications, distress for parents and staff, and potential physical injury. While both clonidine and dexmedetomidine are widely utilized alpha-2 agonists in pediatric practice, real-world prospective comparative data regarding their relative efficacy on ED incidence and recovery timelines remain limited.

Study Design and Methodology This is a single-center, prospective observational cohort study conducted at UZ Brussel. Because this is an observational study evaluating standard-of-care practices, the administration and choice of alpha-2-agonist (IV dexmedetomidine, IV clonidine, or no alpha-2-agonist) are left entirely to the discretion of the attending pediatric anesthesiologist.

Data Collection and Outcomes:

Pediatric patients undergoing elective (adeno)tonsillectomy with or without placement of myringotomy tubes will be observed. Key demographic data, anesthetic techniques, and intraoperative co-analgesics will be recorded. Upon arrival in the PACU, emergence delirium will be systematically assessed using the Pediatric Anesthesia Emergence Delirium (PAED) scale at set time intervals (arrival, 15, 30, 45, and 60 minutes). Secondary endpoints include PACU length of stay (measured against standardized discharge readiness criteria), total time to hospital discharge, requirement for rescue medication, and incidence of perioperative adverse events (such as postoperative nausea and vomiting, desaturation, or laryngospasm).

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Observational

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
150

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

Study Locations

  • Belgium
    • Brussels Capital
      • Jette, Brussels Capital, Belgium, 1090

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

2 years to 12 years (Child)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Sampling Method

Non-Probability Sample

Study Population

The study population consists of pediatric patients aged 2 to 12 years (ASA I-II) scheduled for elective ambulatory (adeno)tonsillectomy with or without placement of myringotomy tubes under general anesthesia at UZ Brussel. Participants are selected from the daily operating room list in the day-surgery unit.

Description

Inclusion Criteria:

  • Children aged 2 to 12 years old.
  • Scheduled for elective (adeno)tonsillectomy or tonsillectomy (with or without concurrent myringotomy/tympanostomy tube insertion).
  • American Society of Anesthesiologists (ASA) physical status I or II.
  • Surgery performed in an ambulatory / day-surgery setting under general anesthesia.
  • Written informed consent provided by parents or legal guardians.

Exclusion Criteria:

  • Known hypersensitivity or allergy to clonidine, dexmedetomidine, or other alpha-2 adrenergic agonists.
  • Pre-existing severe cardiac conduction abnormalities, severe bradycardia, or hemodynamic instability.
  • Severe neurodevelopmental impairment, severe cognitive impairment, or active central nervous system disorders that preclude reliable assessment using the PAED scale.
  • Emergency tonsillectomy or active tonsillar hemorrhage.
  • Patients requiring planned postoperative intensive care unit (PICU) admission or extended inpatient monitoring.
  • Patient or parent/guardian refusal to participate.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Observational Models: COHORT
  • Time Perspectives: PROSPECTIVE

Cohorts and Interventions

Group / Cohort

Group / Cohort

A group or subgroup of participants in an observational study that is assessed for biomedical or health outcomes.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Dexmedetomidine Group

Pediatric patients undergoing elective (adeno)tonsillectomy with or without placement of myringotomy tubes who receive intraoperative intravenous dexmedetomidine as part of standard anesthetic care, at the discretion of the attending anesthesiologist.
Drug: Intravenous dexmedetomidine

Standard of care intraoperative intravenous administration of dexmedetomidine. Dose, timing, and administration are determined solely by the attending anesthesiologist.
Clonidine Group

Pediatric patients undergoing elective (adeno)tonsillectomy with or without placement of myringotomy tubes who receive intraoperative intravenous clonidine as part of standard anesthetic care, at the discretion of the attending anesthesiologist.
Drug: Intravenous clonidine

Standard of care intraoperative intravenous administration of clonidine. Dose, timing, and administration are determined solely by the attending anesthesiologist.
Control Group (No Alpha-2 Agonist)

Pediatric patients undergoing elective (adeno)tonsillectomy with or without placement of myringotomy tubes who do not receive any intraoperative alpha-2 adrenergic agonist (dexmedetomidine or clonidine) as part of standard anesthetic care.
Other: Standard Anesthetic Care Without Alpha-2 Agonist

Standard anesthetic care during pediatric (adeno)tonsillectomy without administration of intraoperative alpha-2 adrenergic agonists.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Incidence and Severity of Emergence Delirium (ED)
Time Frame: Assessed at PACU arrival (T0), and at 15 (T15), 30 (T30), 45 (T45), and 60 (T60) minutes post-operatively until PACU discharge.

Emergence delirium will be assessed using the Pediatric Anesthesia Emergence Delirium (PAED) scale. The PAED scale consists of 5 items, with total scores ranging from 0 to 20, where higher scores indicate greater severity of delirium. A PAED score >= 10 (or >= 12) is defined as the presence of emergence delirium.
Assessed at PACU arrival (T0), and at 15 (T15), 30 (T30), 45 (T45), and 60 (T60) minutes post-operatively until PACU discharge.

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Post-Anesthesia Care Unit (PACU) Length of Stay
Time Frame: From arrival at PACU until discharge readiness, assessed up to 2 hours post-operatively.

Time duration (in minutes) from arrival at the PACU until meeting formal criteria for discharge readiness (e.g., modified Aldrete or PADSS score).
From arrival at PACU until discharge readiness, assessed up to 2 hours post-operatively.
Total Time to Hospital Discharge
Time Frame: From end of surgery until hospital discharge on Day 1 (up to 24 hours).

Time duration (in hours) from the end of anesthesia/surgery until actual discharge from the day-surgery clinic.
From end of surgery until hospital discharge on Day 1 (up to 24 hours).
Incidence of Rescue Medication Administration
Time Frame: During the PACU stay, up to 2 hours post-operatively.

Proportion of patients requiring rescue medication in the PACU for severe emergence delirium or acute postoperative pain (e.g., propofol, opioids, or additional alpha-2 agonists).
During the PACU stay, up to 2 hours post-operatively.
Incidence of Perioperative Adverse Events
Time Frame: From anesthesia induction until discharge from the day-surgery clinic (up to 24 hours).

Occurrence of airway or recovery complications including laryngospasm, oxygen desaturation (<92%), severe postoperative nausea and vomiting (PONV), or excessive sedation.
From anesthesia induction until discharge from the day-surgery clinic (up to 24 hours).

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Universitair Ziekenhuis Brussel

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Hélène De Cuyper, MD, Department of Anesthesiology & Perioperative Medicine

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
December 1, 2026

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
May 31, 2027

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
May 31, 2027

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
October 28, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
October 28, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
November 3, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
November 4, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 2, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
November 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • CLONIDEX

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Patient Privacy & GDPR Compliance:

The study involves a vulnerable pediatric population. Full individual participant data sets, even if pseudonymized, carry a risk of re-identification when combined with detailed clinical and surgical variables, which violates strict European General Data Protection Regulation (GDPR) standards and institutional patient privacy policies.

Absence of Informed Consent for Broad Public Data Sharing:

The informed consent process and ethics committee approval approved for this study specifically cover data collection and analysis by the designated investigation team at UZ Brussel. Participants' legal guardians did not consent to open-access public repository sharing or secondary use of their children's raw individual data by external third parties.

Institutional & Regulatory Restrictions:

In accordance with hospital policy and national regulatory frameworks governing single-center observational clinical research, raw patient-level data remain restricted.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings