NCT05110820

Quantitative Assessment of Pupillary Light Reflex in Acute Carbon Monoxide Poisoning

Quantitative Assessment of Pupillary Light Reflex for the Prediction of Neurocognitive Outcomes of Acute Carbon Monoxide Poisoning: A Prospective Observational Study

• Status: Completed
• Phase: —
• Study type: Observational
• Enrollment: 104 (actual)
• Sponsor: Wonju Severance Christian Hospital · Academic / Other
• Sex: All
• Age: 19 Years
• Healthy volunteers: Not accepted

Summary

Neurological complications after acute carbon monoxide (CO) poisoning can range from transient headache or dizziness to cognitive dysfunction, seizure, permanent anoxic brain damages or death. A recent study reported that a lack of standard pupillary light reflex (sPLR), assessed using a pen light, was a predictor of 30-day neurological sequelae in patients with CO poisoning. Given that the basic sPLR has a poor inter-rater reliability, more objective and quantitative methods are required in the assessment of PLR. An automated pupillometer has been used in the intensive care unit to quantitatively assess the PLR. Therefore, we hypothesized that quantitative assessment of PLR might be associated with neurocognitive sequelae after acute CO poisoning. The purpose of this study was to assess the value of quantitative pupillary reactivity (NPi and qPLR) in comparison to that of sPLR in predicting neurocognitive outcome at 1 month after acute CO poisoning.

Detailed description

Neurological complications after acute carbon monoxide (CO) poisoning can range from transient headache or dizziness to cognitive dysfunction, seizure, permanent anoxic brain damages or death. Although hyperbaric oxygen therapy (HBO2) has been tried to minimize the neurological complications, a significant percentage of patients still suffer from neurocognitive sequelae after acute CO poisoning. A recent study reported that a lack of standard pupillary light reflex (sPLR), assessed using a pen light, was a predictor of 30-day neurological sequelae in patients with CO poisoning. Given that the basic sPLR has a poor inter-rater reliability, more objective and quantitative methods are required in the assessment of PLR. An automated pupillometer has been used in the intensive care unit to quantitatively assess the PLR. Quantitative PLR (qPLR), which is expressed as the percentage pupillary constriction in response to a calibrated light stimulus, was better in predicting neurological outcome after cardiac arrest (CA) compared to standard light reflex. In addition, the Neurological Pupil index (NPi) has been validated as a tool for assessing prognosis after CA because it is not influenced by medications (especially opioids and neuromuscular blocking agents) or small pupil size. Therefore, the investigators hypothesized that quantitative assessment of PLR might be associated with neurocognitive sequelae after acute CO poisoning. The purpose of this study was to assess the value of quantitative pupillary reactivity (NPi and qPLR) in comparison to that of sPLR in predicting neurocognitive outcome at 1 month after acute CO poisoning.

Conditions

• Carbon Monoxide Poisoning

Interventions

Type	Name	Description
DIAGNOSTIC_TEST	Automated quantitative pupillometer	Quantitative measurement of pupillary variables was performed at the time of arrival at the ED (0 h), and at the 6-, 12-, and 24-h time points on hospital day (HD) 1. The worst value among those recorded within 24 h and during the total measurement period was selected as the 24-h and total lowest values. If a patient was discharged before HD 3, measurements were taken only until discharge. The initial value was measured within 1 h after arrival at the ED because of the requisite time for obtaining informed consent before enrollment. At each time point, the lowest values for the NPi and qPLR of each eye were retained for analysis. The sPLR (standard PLR) was serially measured in the ED and after admission by emergency physicians using a manual penlight. We classified the reactivity of the sPLR as reactive, sluggish, or non-reactive. Non-reactive sPLR was defined when pupillary reactivity was not identified bilaterally.

Timeline

• Start date: 2019-08-01
• Primary completion: 2020-12-31
• Completion: 2021-01-31
• First posted: 2021-11-08
• Last updated: 2021-11-08

Locations

1 site across 1 country: South Korea