Pain Assessment by Pupil Dilation Reflex (PDR) and Pupillary Pain Index (PPI) in Response to Noxious Stimulation in Anesthetized Adults

Antwerp University Hospital (UZA)

Status: Completed

Conditions: Monitoring, Intraoperative; Nociceptive Pain

Treatments: Procedure: PDR measurement

Study type: Interventional

Funder types: Other

Identifiers

NCT03140241

16/40/410-2

Details and patient eligibility

About

After conduction a pilot study, pupillary dilation reflex (PDR) is measured in response to nociceptive stimulation perioperatively.

Full description

An infrared camera of the video pupillometer measures the pupillary dilation reflex (PDR) in response to incremental nociceptive stimuli. The PDR is a robust reflex, even in patients under general anesthesia, and may provide a potential evaluation of the autonomous nociceptive circuit. American Society of Anesthesiologists (ASA) classification I or II patients undergoing elective surgery under general anesthesia are recruited. Enrolled patients perioperative undergo PDR measurement at 2 different standardized times (before and after opioid administration) generated by an inbuilt pupillary pain index (PPI) protocol. PPI, as a surrogate for nociception includes noxious stimulations from 10 up to 60 milli ampere (mA) until pupil dilation is larger than 13% from baseline diameter. Therefore, no inappropriate high stimulation is executed.

Enrollment: 34 patients

Sex: All

Ages: 18 to 75 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Scheduled abdominal or gynecological surgery
• ASA I-II

Exclusion criteria

• History of eye deformity, invasive ophthalmologic surgery
• Known cranial nerve(s) deficit
• Infection of the eye
• Predicted difficult airway management (DAF Guidelines)
• Chronic opioid use (>3 months)
• Ongoing treatment with beta-blockers, dopamine antagonists, topical atropine
• Preoperatively administrated benzodiazepins or antiemetics

Trial design

Primary purpose: Diagnostic

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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34 participants in 1 patient group

PDR measurement

Experimental group

Description:

Two measurements of PDR perioperatively before and after opioid administration

Treatment:

Procedure: PDR measurement