# Optic Nerve Sheath Diameter as a Prognostic Tool for Mortality in Intensive Care Unit Patients

## TL;DR

This study shows that measuring the optic nerve sheath diameter in ICU patients can predict mortality, especially in those with sepsis.

## Contribution

The study demonstrates that optic nerve sheath diameter is a reliable non-invasive predictor of mortality in ICU patients.

## Key findings

- Non-survivors had significantly higher ONSD values compared to survivors on ICU admission day.
- ONSD measurement correlates with mortality outcomes, particularly in septic ICU patients.
- The survival rate was 66.2%, with sepsis being highly prevalent among ICU patients.

## Abstract

Background: The relationship between optic nerve sheath diameter (ONSD) and mortality outcomes in critically ill intensive care unit (ICU) patients is an area of increasing interest. This study aimed to explore whether ONSD can serve as a reliable predictor of mortality in ICU patients, potentially offering a non-invasive tool to guide clinical decision-making and patient management.

Materials and methods: This prospective cohort study included critically ill ICU patients aged 14 years and above, excluding those with pre-existing optic nerve disorders, traumatic brain injury (TBI), or intracerebral hemorrhage (ICH). Demographic and clinical data, including age, sex, comorbidities, injury severity score, Glasgow Coma Scale (GCS), and laboratory data, such as liver function tests (LFTs), hemoglobin (Hb) level, and procalcitonin (PCT) level, were collected. ONSD was measured on Day 1 and Day 10 using transorbital ultrasonography. Statistical analysis was performed using IBM SPSS Statistics for Windows, Version 21 (released 2012; IBM Corp., Armonk, New York, United States) to determine the association between ICU mortality and other outcomes.

Results: The patients in this study had a mean age of 58.29 years, with the majority presenting with comorbidities such as diabetes mellitus (DM) and hypertension (HTN). Clinical outcomes showed significant reductions in C-reactive protein (CRP) over ten days, with a notable prevalence of sepsis (91.2%) and a survival rate of 66.2%, while the ONSD values on ICU admission day were significantly higher in non-survivors (mean right/left ONSD = 4.02/3.97 mm) versus survivors (mean right/left ONSD = 3.68/3.67 mm), with p-values of 0.001 indicating statistical significance.

Conclusions: ONSD measurement is a valuable prognostic tool in ICU patients, correlating with mortality outcomes, especially in septic patients, and can help guide timely interventions for better outcomes.