An interventional study of Pupillary dilation reflex and Standard of care in Pain, Acute and Anesthesia, sponsored by University Hospital, Antwerp. Completed at 1 site in Belgium. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2023-05-15.
Sponsored by University Hospital, Antwerp · Not applicable, Interventional, and Treatment
In this double blinded randomized controlled study, the pupillary dilation reflex is used for as a nociceptive indicator for opioid administration during elective surgery under general anesthesia.
An infrared camera of the video pupillometer measures the pupillary dilation reflex (PDR) in response of a nociceptive stimulus. This autonomic reflex, parasympathetic mediated in sedated patients, can be generated by various pain stimuli (built in standardized protocol, surgical incision, ...) The PDR is a robust reflex, even in patients under general anesthesia, and provides a potential evaluation of the autonomous circuit within the nociceptive evaluation based on pupil dilation upon A-delta and C fibers in both electrical or mechanic stimulation. This double blind randomized controlled trial involving American Society of Anesthesiologists (ASA) classification I-III patients undergoing elective surgery under general anesthesia are recruited. Enrolled patients are randomized in four groups: (1) remifentanil administration depending on PDR results, (2) remifentanil administration depending on decision attending anesthesiologist, (3) sufentanil administration depending on PDR results, (4) sufentanil administration depending on decision attending anesthesiologist.
Exclusion Criteria:
Pupillary dilation reflex based perioperative intravenous remifentanil administration. Starting dose 5 ng/ml by continous infusion, dosage adjustments are made after pupillary dilation reflex assessment every 10 minutes. When PPI score is 1, the dosage is decreased with 0.2 ng/ml. When PPI score is greater than 1, the dosage is increased with 0.2 ng/ml.
Diagnostic Test: Pupillary dilation reflex
Anesthesiologist based perioperative intravenous remifentanil administration (daily practice, standard of care). Starting dose 5 ng/ml, dosage adjustments are made when deemed necessary by attending anesthesiologist.
Other: Standard of care
Pupillary dilation reflex based perioperative intravenous sufentanil administration. Starting dose 0.1 mcg/kg bolus, dosage adjustments are made after pupillary dilation reflex assessment every 10 minutes. When PPI score is 1, no supplementary administration is executed. When PPI score is greater than 1, a supplementary bolus of 0.1 mcg/kg is given.
Diagnostic Test: Pupillary dilation reflex
Anesthesiologist based perioperative intravenous sufentanil administration (daily practice, standard of care). Starting dose 0.1 mcg/kg bolus, dosage adjustments are made when deemed necessary by attending anesthesiologist.
Other: Standard of care
Perioperative pupillary dilation reflex assessment is executed every 10 minutes from start sedation until extubation in patients allocated to study arm Intervention 1 and Intervention 3
Perioperative opioid administration based on the attending anesthesiologist decision (mainly including assessment of heart rate, blood pressure, and limb movement)
Postoperative pain
Numeric rating scale (NRS) pain assessment
Time frame: From patient extubation until postoperative day 5
Postoperative analgesia
Analgetic consumption
Time frame: From patient extubation until postoperative day 5
Stimulation intensity to elicit PDR
Necessary stimulation intensity generated by the pupillometer to elicit a PDR
Time frame: From the day of surgery at the start of general anesthesia, assessed every 10 minutes until the end of surgery or extubation, whichever came first, assessed up to 4 hours
Baseline pupil diameter
Pupil size before stimulation
Time frame: From the day of surgery at the start of general anesthesia, assessed every 10 minutes until the end of surgery or extubation, whichever came first, assessed up to 4 hours
Pupillary dilation reflex amplitude
The amplitude of the pupil enlargement after nociceptive stimulation
Time frame: From the day of surgery at the start of general anesthesia, assessed every 10 minutes until the end of surgery or extubation, whichever came first, assessed up to 4 hours
Pupillary pain index (PPI)
Generated PPI score by the pupillometer in accordance to given stimulation and pupillary dilation reflex amplitude
Time frame: From the day of surgery at the start of general anesthesia, assessed every 10 minutes until the end of surgery or extubation, whichever came first, assessed up to 4 hours
Opioid usage during surgery
Total dose remifentanil or sufentanil administrated during surgery, in microgram
Time frame: From the day of surgery at the start of general anesthesia, assessed every 10 minutes until the end of surgery or extubation, whichever came first, assessed up to 4 hours
Extubation time
The time between stop of propofol administration and patient extubation, in minutes
Time frame: From the day of surgery at the termination of propofol infusion until patient extubation, assessed up to 2 hours
Postoperative nausea and vomiting
Frequency of nausea or vomiting after surgery, in numbers of events
Time frame: From patient extubation until postoperative day 5
Length of stay at the postanesthesia care unit
Hours of admission at the postanesthesia care unit after surgery until discharge to the nursing ward, in minutes
Time frame: From admission at the postanesthesia care unit until discharge to the nursing ward, assessed up to 24 hours
Length of hospital stay
Length of hospital stay, in days
Time frame: From the day of the planned surgery until hospital discharge, assessed up to 5 days
Postoperative health status
Assessed by 5-level EQ-5D version (EQ-5D-5L), quality of life and health status questionnaire
Time frame: From extubation until 1 month after surgery
Plan to share: Undecided
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University Hospital, Antwerp