Anesthesia, Pain, Acute
Conditions
Keywords
pupillary reflex, nociception, heart rate, intraoperative monitoring
Brief summary
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.
Detailed description
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.
Interventions
DIAGNOSTIC_TESTPupillary dilation reflex
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
OTHERStandard of care
Perioperative opioid administration based on the attending anesthesiologist decision (mainly including assessment of heart rate, blood pressure, and limb movement)
Sponsors
Universiteit Antwerpen
University Hospital, Antwerp
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Caregiver, Outcomes Assessor)
Masking description
The patient, the performer of the pupillary reflex measurement, and the postoperative health care provider are masked for the study arms.
Intervention model description
Double blinded randomized controlled trial
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* \> 18 jaar * Elective abdominal or gynaecological operation * ASA (American Society of Anesthesiologists classification): I - II - III
Exclusion criteria
* History of invasive ophthalmological surgery * Known bilateral eye disease * Known optical of oculomotor nerve deficit * Active psychiatrical disease * Proven active pheochromocytoma * Opioid usage \> 7 days preoperative * Ongoing oncological treatment with chemotherapeutic agents * Usage of A-1 adrenergic of beta-blocking agents * Preoperative usage of benzodiazepines * Topical atropine or phenylephrine (eye droplets) * Planned perioperative usage of dopamine antagonists
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Postoperative pain | From patient extubation until postoperative day 5 | Numeric rating scale (NRS) pain assessment |
| Postoperative analgesia | From patient extubation until postoperative day 5 | Analgetic consumption |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Pupillary dilation reflex amplitude | 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 | The amplitude of the pupil enlargement after nociceptive stimulation |
| Pupillary pain index (PPI) | 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 | Generated PPI score by the pupillometer in accordance to given stimulation and pupillary dilation reflex amplitude |
| Opioid usage during surgery | 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 | Total dose remifentanil or sufentanil administrated during surgery, in microgram |
| Extubation time | From the day of surgery at the termination of propofol infusion until patient extubation, assessed up to 2 hours | The time between stop of propofol administration and patient extubation, in minutes |
| Stimulation intensity to elicit PDR | 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 | Necessary stimulation intensity generated by the pupillometer to elicit a PDR |
| Length of stay at the postanesthesia care unit | From admission at the postanesthesia care unit until discharge to the nursing ward, assessed up to 24 hours | Hours of admission at the postanesthesia care unit after surgery until discharge to the nursing ward, in minutes |
| Length of hospital stay | From the day of the planned surgery until hospital discharge, assessed up to 5 days | Length of hospital stay, in days |
| Postoperative health status | From extubation until 1 month after surgery | Assessed by 5-level EQ-5D version (EQ-5D-5L), quality of life and health status questionnaire |
| Postoperative nausea and vomiting | From patient extubation until postoperative day 5 | Frequency of nausea or vomiting after surgery, in numbers of events |
| Baseline pupil diameter | 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 | Pupil size before stimulation |
Countries
Belgium
Outcome results
None listed