Neuroanaesthesia & neurocritical care
Comparison of two automated pupillometry indices in patients with acute brain injury: the prospective multicentre LYNX cohort study
Authors' conclusion
NPi and QPi were correlated and both predicted 6-month outcome, but QPi was far more sensitive to anaesthetics, which probably confounds its association with intracranial hypertension.
Study context
- Population
- Consecutive adults with TBI, subarachnoid or intracerebral haemorrhage, or ischaemic stroke ventilated >12 h, three European ICUs (September 2022-July 2024)7,089 paired measurements
- Participants
- 108 adults
- Exposure
- Quantitative pupil index (QPi) vs neurological pupil index (NPi) automated pupillometry indices
- Outcome
- Correlation between the two indices
Methodological detailsmulticentre, paired measurements, ancillary cohorts of healthy volunteers and surgical patients
- Multicentre
- Paired measurements
- Ancillary cohorts of healthy volunteers and surgical patients
Main finding
As reported in the abstract
Correlation between NPi and QPi
Correlation (r), 95% CI 0.705-0.730; moderately to strongly correlated
0.717
Observational data: associations, not effects.
Secondary outcomes
| Outcome | OR (95% CI) | P value | |
|---|---|---|---|
| Unfavourable 6-month outcome (GOS-E ≤ 4), per 10-percentage-point increase in abnormal values · 6 monthsNPi · independent predictor | 1.49 (1.09–2.04) | P = 0.013 | |
| Unfavourable 6-month outcome (GOS-E ≤ 4), per 10-percentage-point increase in abnormal values · 6 monthsQPi · independent predictor | 1.76 (1.31–2.37) | P < 0.001 | |
| Intracranial hypertension | 1.38 (1.04–1.82) | P = 0.025 | |
| 0.512Odds ratio (log scale) |
Median
| Outcome | NPi | QPi |
|---|---|---|
| Index values after propofol (sedated non-brain-injured patients) | 4.0 (IQR 3.6–4.3) | 1 (IQR 1–3) |
- Unfavourable 6-month outcome (GOS-E ≤ 4), per 10-percentage-point increase in abnormal values: multivariable models adjusted for age, sex, admission GCS and focal deficit
- Index values after propofol (sedated non-brain-injured patients): 20 sedated non-brain-injured patients
Intracranial hypertension
- NPi not associated with intracranial hypertension
Effect of ambient lighting and contralateral eye opening (healthy volunteers)
- No meaningful effect in 75 volunteers
Original publication
Comparison of two automated pupillometry indices in patients with acute brain injury: the prospective multicentre LYNX cohort study. Crit Care. Published 28 September 2026. doi:10.
Composed by AI from the published abstract and checked against it. How Briefs are made →