Evidence map›Paper›PMID 41540509›Full record

ArticleJournal of anesthesia, analgesia and critical care2026

The effect of opioids on the light-off pupillary reflex.

Rachel Eshima McKay, Merlín D Larson

Abstract read
In one paragraph

Article in Journal of anesthesia, analgesia and critical care, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

2 authors.

Rachel Eshima McKayDepartment of Anesthesia and Perioperative Care, University of California San Francisco (UCSF), San Francisco, CA, 94143, USA.ORCID http://orcid.org/0000-0001-9019-0589
Merlín D LarsonDepartment of Anesthesia and Perioperative Care, University of California San Francisco (UCSF), San Francisco, CA, 94143, USA. merlin.larson@ucsf.edu.ORCID http://orcid.org/0000-0003-0021-5602

Funding

: Financial support was obtained by a grant from the UCSF Mount Zion Health Fund (Award # 2021133). 2021133
6 · The paper itself

Abstract

objectiveWe examined the relationship between modeled opioid concentration and quantitative pupillary measures during remifentanil infusion sequences with particular attention to the "light-off" (LO) reflex.

methodsTen volunteer subjects were recruited to undergo two 10-min remifentanil infusion protocols. Pupillary unrest in ambient light (PUAL) and LO were measured at baseline and every 2.5 min during the first 10-min infusion-25-min recovery sequence, and after a wash-out period, the Neurological Pupillary index (NPi) and LO were measured during an identical infusion-recovery sequence. We tested proportional change in each parameter from baseline as indicators of dynamic opioid effect.

resultsOn average, remifentanil decreased both LO dilation and PUAL by > 85%, decreased pupil diameter by > 48%, but did not significantly alter the NPi. Hypoxia occurred in 15/16 sequences. LO and PUAL both showed excellent discrimination between high-toxic versus zero-moderate opioid effect. In contrast to PUAL and LO, the scaled pupillary light reflex measurement (NPi) was not altered by opioids.

conclusionLO and PUAL were robust indicators of opioid effect and provided equivalent estimates of respiratory depression risk in our healthy awake subjects. Compared with PUAL, LO offers the advantage of being intuitive and easily derived at the bedside without need for specialized software. SIGNIFICANCE: Measurement of the pupillary LO reflex with a portable pupillometer provides a simple, discriminating measure of opioid effect. Remifentanil blocks the pupillary LO reflex.

Indexed as

NeuromonitoringOpioidsPupilPupillary light reflexPupillometry

Identifiers

PMID41540509
PMCPMC12892534

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.