Merve İkbal GÖNCÜ, Engin İhsan TURAN, Ezgi AYDIN İNAN, Oktay İNAN, Ebru KAYA, Ayça Sultan ŞAHİN
Türk Yoğun Bakım Dergisi - 2026;24(1):21-29
Objective: Optic nerve sheath diameter (ONSD) has been increasingly recognized as a non-invasive surrogate marker for intracranial pressure (ICP) in critically ill patients. The Glasgow Coma Scale (GCS) is a widely used tool for assessing neurological status. However, the relationship between GCS and ONSD in intensive care unit (ICU) patients remains underexplored. This study aimed to investigate the association between ONSD and GCS scores in ICU patients, while also evaluating the impact of positive end-expiratory pressure (PEEP) on ONSD measurements. Methods: This prospective observational study included 66 ICU patients. ONSD measurements were obtained using ultrasonography at 24 and 48-72 hours after ICU admission. Patients were categorized into three groups based on GCS scores (3-7, 8-11, 12-15). The effect of PEEP and other clinical parameters on ONSD was analyzed using linear mixed models, with a significance level of p < 0.05. Results: ONSD was significantly higher in patients with lower GCS scores (p < 0.001). Additionally, PEEP application was strongly associated with increased ONSD (p < 0.001), whereas other factors such as mean arterial pressure, heart rate, and sepsis status did not show significant effects. Conclusion: ONSD is significantly associated with GCS scores, supporting its role as a non-invasive marker of neurological deterioration. The influence of PEEP on ONSD suggests a potential impact of mechanical ventilation on ICP dynamics, warranting further investigation.
