Opioid; Intoxication, Perception Disturbance (Acute), Acute Pain, Overdose of Opiate, Respiratory Depression, Safety Issues
Conditions
Brief summary
Volunteers will receive a weight-based opioid (remifentanil) infusion for 10 minutes. In the first run, serial pupillary measurements (pupillary unrest, pupil diameter) will be taken at baseline, and at 2.5-minute intervals during the infusion and a 25-minute recovery period afterwards. After a washout period, the experiment will be repeated in each subject (second run). The two runs differ only by presence versus absence of verbal interaction.
Detailed description
Healthy volunteers aged 20-55 will receive a weight-based opioid (remifentanil) infusion for 10 minutes. Vital signs including SpO2, transcutaneous CO2, and respiratory rate will be continuously measured. In the first run, serial pupillary measurements (pupillary unrest, pupil diameter) will be taken at baseline, and at 2.5-minute intervals during the infusion and a 25-minute recovery period afterwards. After a washout period, the experiment will be repeated in each subject (second run). The two runs differ only by presence of ongoing verbal interaction versus complete avoidance of verbal interaction. Incidence of respiratory depression will be compared in the two protocols with or without verbal interaction. Correlation between pupil diameter and pupillary unrest with estimated opioid concentrations will be determined by regression. Difference between pupil measurement versus opioid concentration regressions will be compared by chi2.
Interventions
BEHAVIORALContinuous conversational interaction
Maintaining continuous conversation, requiring that the subject answer questions and engage in discussion without interruption.
10 minute remifentanil infusion
Sponsors
University of California, San Francisco
Study design
Allocation
NON_RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
DIAGNOSTIC
Masking
NONE
Intervention model description
Each subject is his/her own control.
Eligibility
Sex/Gender
ALL
Age
20 Years to 55 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthy * Able to provide informed consent
Exclusion criteria
* Active substance use disorder * Prior opioid use disorder * Opioid use within 30 days.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Impact of environmental stimulation on decline in oxygen saturation to ≤ 90%. | 35 minutes | Conversational interaction and oxygen saturation measured by pulse oximeter. |
| Impact of environmental stimulation on CO2 increase of 15% or more above baseline. | 35 minutes | Conversational interaction and CO2 measured by transcutaneous sensor. |
| Correlation between estimated opioid concentration and deviation in pupillary measurement. | 35 minutes | Relationship of opioid concentration to pupillary unrest, measured by the pupillometer |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Impact of environmental stimulation on opioid-related deviations in pupillary measurements. | 35 minutes | Impact of conversational interaction on degree of decline in pupillary unrest as measured by the pupillometer. |
Countries
United States
Outcome results
None listed