Pupil Dilation and Analgesia Nociception Index

Vrije Universiteit Brussel

Status: Completed

Conditions: Pain

Treatments: Diagnostic Test: Measurement of pupil dilation and analgesia nociception index

Study type: Interventional

Funder types: Other

Identifiers

NCT03280238

2016/278

Details and patient eligibility

About

Pain assessment is crucial in clinical practice. Currently, subjective self-report is considered the most appropriate method to evaluate pain. Although several methods to assess pain objectively exist, the lack of a golden standard still remains. This pilot study assesses the changes in pupil dilation (PD) and the analgesia nociception index (ANI) as a measure of pain in healthy, conscious, male volunteers in a highly standardized and individualized environment. Nineteen subjects received three blocks of 4 individualized electrical stimulus intensities, ranging from no to severe pain. Subjects reported their perceived severity of each individual stimulus, enabling the comparison of changes in PD and ANI in relation to both administered stimulus intensities and perceived pain severities. PD and ANI were measured before and after each administration of a stimulus.

Enrollment: 19 patients

Sex: Male

Ages: 18 to 35 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• good health
• no acute or chronic pain conditions
• well rested

Exclusion criteria

• chronic treatment
• bad health
• daily use of analgetics or other medication
• weekly tobacco use
• weekly use of recreational drugs
• more than 10 alcohol consumptions a week

Trial design

Primary purpose: Diagnostic

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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19 participants in 1 patient group

Experiment

Experimental group

Description:

* Individualized painful electrical stimuli, Surpass LT stimulator (EMS Biomedical, Korneuburg, Austria) with a bipolar felt pad electrode * Measurement of pupil diameter, Algiscan® (iDMed, Marseille, France) * Measurement of Analgesia Nociception Index, PhysioDoloris® (MetroDoloris, Lille, France)

Treatment:

Diagnostic Test: Measurement of pupil dilation and analgesia nociception index