Pupillary Reflex ImpairedNCT04307238
Effects of Different Types of General Anesthesia on Postoperative Pupillary Reactivity
A study testing PLR, Alertness testing and Propofol anesthesia in people with Pupillary Reflex Impaired, run by Medical University of Vienna at 1 site in Austria.
Trial summary
Objective: To compare the effects of volatile and intravenous anesthetics on pupillary function after general anesthesia using a portable infrared pupillometer. Design: A monocentric, prospective, double blinded randomized study. Read more about this study
- Who is it for?
- Ages 18 to 99 years
- Conditions the study is for
- Pupillary Reflex Impaired
- What is being tested?
- PLR, Alertness testing and Propofol anesthesia
- Type of treatment
- Injection or infusion, Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 108 participants
- Where
- 1 siteAustria
- Study dates
- 9 Mar 2020to 10 Mar 2026
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 99 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Patients aged ≥ 18 and ≤99 years
- ASA I-II
- Patients undergoing elective ENT surgery under general anesthesia
Who cannot join
- Patients aged < 18 and >99 years
- consumption of antidepressants, tranquilizer, psychotropic medications
- history of mental illness, neurosurgery, neurological or psychiatric disease
- ophthalmologic disease
- preexisting cognitive impairment
- Patients with drug dependence, alcoholism
- the patients' inability to follow procedures
- implanted electronic medical devices
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Austria1 site, 1 recruiting
- Recruiting
Medical University Vienna
Vienna, State of Vienna, 1090
Marita Windpassinger, MD, +43140400 ext. 41020, marita.windpassinger@meduniwien.ac.at
Olga Plattner, MD, +43140400 ext. 41020, olga.plattner@meduniwien.ac.at
About this study
Official title: Infrared Pupillometry - Effects of Different Types of General Anesthesia on Postoperative Pupillary Reactivity
Objective: To compare the effects of volatile and intravenous anesthetics on pupillary function after general anesthesia using a portable infrared pupillometer.
Design: A monocentric, prospective, double blinded randomized study.
Read more
Patients: Patients who require elective Ear, Nose and Throat (ENT) surgery under general anesthesia.
Interventions: Patients undergoing elective ENT surgery will be assigned to intravenous versus inhalative anesthesia and pupillometric parameters monitored postoperative, using an infrared pupillometer.
Outcomes measures: Reported pupillometric parameters after intravenous and inhalative anesthesia.
The purpose of this study is to compare general anesthesia techniques (volatile, intravenous) on postoperative changes in pupillary reactivity by using infrared pupillometry.
Read the detailed description
Introduction: With the increased focus on early discharge after surgery and anesthesia, it is important to identify objective criteria that can be used to assess home-readiness after ambulatory surgery. Premature discharge may lead to a higher rate of patients suffering complications and to an increased readmission rate. Time-consuming objective evaluations of postoperative vigilance status like EEG registrations are not practicable in routine postoperative clinical practice.
In this study an approach to a more quantitative judgment of postoperative vigilance and consciousness is made by recording pupillometric measurements using a portable infrared pupillometer. The findings of this study may provide new important insights to the meaning of pupillary responses for postoperative vigilance measurement.
Aim: With regard to the lack of knowledge about mechanisms that enable the central nervous system to restore consciousness after the deep functional disorder of the anesthetized state, this study aims to compare general anesthesia techniques (volatile, intravenous) on postoperative changes in pupillary reactivity by using infrared pupillometry.
The primary aim of this study is to investigate changes in pupillary reactivity (pupillary light reflex (PLR, %) in the early postoperative phase (2 hours) after common used types of general anesthesia techniques (inhaled - sevoflurane versus intravenous - propofol).
Secondary aim is to examine whether decreased postoperative PLR predicts a decline in neuropsychological testing (alertness).
Hypotheses: The investigators hypothesis that changes in PLR within the first 2 postoperative hours differs depending on the anesthesia technique used, with a lower decline in PLR after propofol compared to sevoflurane anesthesia.
Furthermore, the investigators hypothesis that postoperative PLR correlates with changes in alertness measured by a neuropsychological test.
Design: This study will be a prospective, randomized double blinded study.
Methods: The study is approved by the local ethics committee and written informed consent will be obtained from each patient. A total of 108 patients aged ≥18 and ≤99 years, with American Society of Anesthesiologist (ASA) physical status scores I-II, scheduled for elective ENT surgery will be enrolled. Baseline assessment of pupillometry and neuropsychological test will be carried out before surgery (baseline) and at predefined time intervals during the first 2 postoperative hours after the end of anesthesia. Results (AUC, PLR%) will be compared between both anesthesia groups.
Primary outcome parameter will be the AUC of PLR (percentage change, %) measured every 15 minutes during the first 2 postoperative hours. Secondary outcome parameter will include the neuropsychological test score (Digit Symbol Substitution Test (DSST), the Visual Intrinsic Alertness Test (VIA) and the Trail making Test (TMT)) will be performed every 30 minutes after general anesthesia (sevoflurane, propofol maintained).), assessed every 30 min up to 2 hours after discontinuation of anesthesia.
- Conditions
- Pupillary Reflex Impaired
- Being tested
- PLR, Alertness testing, Propofol anesthesia, Sevoflurane anesthesia
- Keywords
- Pupillary Light Reflex, General Anesthesia, Postoperative Vigilance, Alertness, Postoperative Recovery, Infrared Pupillometry
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
PLRDiagnostic test
Also called Pupillary light reflex
PLR measurements will be performed within the first 2 postoperative hours.
Alertness testingDiagnostic test
Also called DSST, VIA, TMT
Preoperative (baseline) and every 30 minutes postoperative computer based alertness testing will be performed.
Propofol anesthesiaProcedure or surgery
Maintenance of anesthesia will be performed using propofol.
Sevoflurane anesthesiaProcedure or surgery
Maintenance of anesthesia will be performed using sevoflurane.
| Study group | Role | What they receive |
|---|---|---|
| Propofol group | Other | General anesthesia will be maintained by continually intravenous administered propofol. Receives: Diagnostic Test: PLR; Diagnostic Test: Alertness testing; Procedure: Propofol anesthesia |
| Sevoflurane Group | Other | General anesthesia will be maintained by inhalative administered sevoflurane. Receives: Diagnostic Test: PLR; Diagnostic Test: Alertness testing; Procedure: Sevoflurane anesthesia |
What is being measured
The primary outcome is the main question the study is designed to answer.
The AUC of Pupillary Light Reflex
The AUC of PLR (percentage change, %) measured every 15 minutes during the first 2 postoperative hours.
Measured: baseline and within the first 2 postoperative hours
Secondary outcomes (3)
Alertness assessed with the Visual Intrinsic Alertness Test Score
Neuropsychological test scores of the Visual Intrinsic Alertness Test (VIA) will be assessed every 30 min up to 2 hours after general anesthesia (sevoflurane, propofol maintained).During the VIA test, the participant has to press a button as fast as possible whenever a black circle (diameter 30 mm) appears in the centre of the computer screen. The circle appears for 1500 ms and disappears if no response is given within this time interval. Interstimulus intervals vary between 3-5 s. The tests used are standardised and scores are measured in milliseconds, higher values/scores mean a worse outcome.
Measured: baseline and within the first 2 postoperative hours
Alertness assessed with the Trail making Test Score
Neuropsychological test scores of the Trail making Test (TMT) will be assessed every 30 min up to 2 hours after general anesthesia (sevoflurane, propofol maintained). The TMT test consists of two parts in which the subject is instructed to connect a set of 25 dots as quickly as possible. In the first part, the targets are all numbers (1, 2, 3, etc.) and the test taker needs to connect them in sequential order. In the second part, the subject alternates between numbers and letters (1, A, 2, B, etc.). If the subject makes an error, the test administrator corrects them before the subject moves on to the next dot.
The goal of the test is for the subject to finish both parts as quickly as possible, with the time taken to complete the test being used as the primary performance metric. The tests used are standardised and scores are measured in seconds, higher values/scores mean a worse outcome.
Measured: baseline and within the first 2 postoperative hours
Alertness assessed with the Digit Symbol Substitution Test
Neuropsychological test scores of the Digit Symbol Substitution Test (DSST) will be assessed every 30 min up to 2 hours after general anesthesia (sevoflurane, propofol maintained). Scores range from 0 to 100, with higher scores indicating higher cognitive function.
The DSST test consists of 9 digit-symbol pairs (e.g. 1/-,2/┴ ... 7/Λ,8/X,9/=) followed by a list of digits. Under each digit the subject should write down the corresponding symbol as fast as possible. The number of correct symbols within the allowed time (90 sec) is measured. The tests used are standardised and scores are measured in seconds, higher values/scores mean a worse outcome.
Measured: baseline and within the first 2 postoperative hours
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted13 Mar 2020
- Study start9 Mar 2020
- Primary completion10 Mar 2026 (estimated)
- Study completion10 Mar 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Pupillary Reflex ImpairedStudies of the same condition, open and under way.
- More trials run by Medical University of ViennaThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 108 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Medical University of Vienna
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Marita Windpassinger M.D., Medical University of Vienna
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04307238
- Sponsor's protocol ID
- 1520/2019
- Status last verified
- Jul 2025
- First submitted
- 22 Nov 2019
- Last updated
- 4 Jul 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 4 Jul 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Infrared Pupillometry - Effects of Different Types of General Anesthesia on Postoperative Pupillary Reactivity
- ClinicalTrials.gov ID
- NCT04307238
- Acronym / sponsor ID
- 1520/2019
- Conditions
- Pupillary Reflex Impaired
- Keywords
- Pupillary Light Reflex, General Anesthesia, Postoperative Vigilance, Alertness, Postoperative Recovery, Infrared Pupillometry
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 108 participants (estimated)
- Lead sponsor
- Medical University of ViennaUniversity, hospital or other
- Study start
- 9 Mar 2020 (actual)
- Primary completion
- 10 Mar 2026 (estimated)
- Study completion
- 10 Mar 2026 (estimated)
- First posted
- 13 Mar 2020 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Objective: To compare the effects of volatile and intravenous anesthetics on pupillary function after general anesthesia using a portable infrared pupillometer.
Design: A monocentric, prospective, double blinded randomized study.
Patients: Patients who require elective Ear, Nose and Throat (ENT) surgery under general anesthesia.
Interventions: Patients undergoing elective ENT surgery will be assigned to intravenous versus inhalative anesthesia and pupillometric parameters monitored postoperative, using an infrared pupillometer.
Outcomes measures: Reported pupillometric parameters after intravenous and inhalative anesthesia.
The purpose of this study is to compare general anesthesia techniques (volatile, intravenous) on postoperative changes in pupillary reactivity by using infrared pupillometry.
Detailed description
Introduction: With the increased focus on early discharge after surgery and anesthesia, it is important to identify objective criteria that can be used to assess home-readiness after ambulatory surgery. Premature discharge may lead to a higher rate of patients suffering complications and to an increased readmission rate. Time-consuming objective evaluations of postoperative vigilance status like EEG registrations are not practicable in routine postoperative clinical practice.
In this study an approach to a more quantitative judgment of postoperative vigilance and consciousness is made by recording pupillometric measurements using a portable infrared pupillometer. The findings of this study may provide new important insights to the meaning of pupillary responses for postoperative vigilance measurement.
Aim: With regard to the lack of knowledge about mechanisms that enable the central nervous system to restore consciousness after the deep functional disorder of the anesthetized state, this study aims to compare general anesthesia techniques (volatile, intravenous) on postoperative changes in pupillary reactivity by using infrared pupillometry.
The primary aim of this study is to investigate changes in pupillary reactivity (pupillary light reflex (PLR, %) in the early postoperative phase (2 hours) after common used types of general anesthesia techniques (inhaled - sevoflurane versus intravenous - propofol).
Secondary aim is to examine whether decreased postoperative PLR predicts a decline in neuropsychological testing (alertness).
Hypotheses: The investigators hypothesis that changes in PLR within the first 2 postoperative hours differs depending on the anesthesia technique used, with a lower decline in PLR after propofol compared to sevoflurane anesthesia.
Furthermore, the investigators hypothesis that postoperative PLR correlates with changes in alertness measured by a neuropsychological test.
Design: This study will be a prospective, randomized double blinded study.
Methods: The study is approved by the local ethics committee and written informed consent will be obtained from each patient. A total of 108 patients aged ≥18 and ≤99 years, with American Society of Anesthesiologist (ASA) physical status scores I-II, scheduled for elective ENT surgery will be enrolled. Baseline assessment of pupillometry and neuropsychological test will be carried out before surgery (baseline) and at predefined time intervals during the first 2 postoperative hours after the end of anesthesia. Results (AUC, PLR%) will be compared between both anesthesia groups.
Primary outcome parameter will be the AUC of PLR (percentage change, %) measured every 15 minutes during the first 2 postoperative hours. Secondary outcome parameter will include the neuropsychological test score (Digit Symbol Substitution Test (DSST), the Visual Intrinsic Alertness Test (VIA) and the Trail making Test (TMT)) will be performed every 30 minutes after general anesthesia (sevoflurane, propofol maintained).), assessed every 30 min up to 2 hours after discontinuation of anesthesia.
Study design
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, investigator)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Propofol group | Other | Diagnostic Test: PLR, Diagnostic Test: Alertness testing, Procedure: Propofol anesthesiaGeneral anesthesia will be maintained by continually intravenous administered propofol. |
| Sevoflurane Group | Other | Diagnostic Test: PLR, Diagnostic Test: Alertness testing, Procedure: Sevoflurane anesthesiaGeneral anesthesia will be maintained by inhalative administered sevoflurane. |
Who may qualify
- Ages
- 18 to 99 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- Patients aged ≥ 18 and ≤99 years
- ASA I-II
- Patients undergoing elective ENT surgery under general anesthesia
Key exclusion criteria (8 listed)
- Patients aged < 18 and >99 years
- consumption of antidepressants, tranquilizer, psychotropic medications
- history of mental illness, neurosurgery, neurological or psychiatric disease
- ophthalmologic disease
- preexisting cognitive impairment
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| PLRAlso: Pupillary light reflexPLR measurements will be performed within the first 2 postoperative hours. | Diagnostic test | Propofol group, Sevoflurane Group |
| Alertness testingAlso: DSST, VIA, TMTPreoperative (baseline) and every 30 minutes postoperative computer based alertness testing will be performed. | Diagnostic test | Propofol group, Sevoflurane Group |
| Propofol anesthesiaMaintenance of anesthesia will be performed using propofol. | Procedure or surgery | Propofol group |
| Sevoflurane anesthesiaMaintenance of anesthesia will be performed using sevoflurane. | Procedure or surgery | Sevoflurane Group |
Primary outcome
The AUC of Pupillary Light Reflex
Time frame: baseline and within the first 2 postoperative hours
The AUC of PLR (percentage change, %) measured every 15 minutes during the first 2 postoperative hours.
3 secondary outcomes
Alertness assessed with the Visual Intrinsic Alertness Test Score
Time frame: baseline and within the first 2 postoperative hours
Alertness assessed with the Trail making Test Score
Time frame: baseline and within the first 2 postoperative hours
Alertness assessed with the Digit Symbol Substitution Test
Time frame: baseline and within the first 2 postoperative hours
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 4 Jul 2025.
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing PLR, Alertness testing and Propofol anesthesia in people with Pupillary Reflex Impaired, run by Medical University of Vienna at 1 site in Austria.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 4 Jul 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Austria. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Marita Windpassinger, MD (+43 1 40400 41020, marita.windpassinger@meduniwien.ac.at), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
The AUC of Pupillary Light Reflex (time frame: baseline and within the first 2 postoperative hours). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 4 Jul 2025; AzTrials last refreshed its copy on 7 Nov 2026.