Research on the use of bedside ultrasound to quickly evaluate neurological prognosis in patients with ROSC

This study aims to find a quick bedside ultrasonography evaluation technique that evaluates the optic nerve sheath diameter to eyeball transverse diameter (ONSD/ETD) ratio and middle cerebral artery (MCA) flow parameters at 6 hours post-return of spontaneous circulation (ROSC) for early neurological prognosis.

This retrospective study included 49 patients who achieved return of spontaneous circulation (ROSC) and were admitted to our emergency department between September 2023 and September 2025. Collected data encompassed baseline characteristics, GCS-M scores, APACHE-II scores, and bedside ultrasound measurements of ONSD, ONSD/ETD at 6, 24, and 48 hours post‑ROSC and middle cerebral artery hemodynamic parameters at 6, 24 hours post‑ROSC. The statistical analyses included the Mann-Whitney U test, t-test, and Receiver Operating Characteristic (ROC) curve analysis.

The ONSD/ETD ratio at 6 hours post-ROSC was a robust predictor of unfavorable neurological outcomes (AUC 0.922, P = 0.001), outperforming ONSD alone (AUC 0.866, P = 0.003), with an optimum threshold of 0.256 (sensitivity 76.5%, specificity 100%). The ONSD/ETD ratio was a significant predictor of CPC scores (OR = 1.979, P = 0.010). Although the majority of middle cerebral artery hemodynamic measures revealed no significant changes, all patients displaying cerebral circulatory arrest (CCA) waveforms or advancing to such waveforms demonstrated a dismal neurological prognosis. The alteration in Pulsatility Index (PI) was borderline significant (P = 0.05), with a threshold of 0.269 (AUC 0.90, sensitivity 80%, specificity 100%).

The ONSD/ETD ratio assessed six hours after cardiac arrest accurately forecasts neurological prognosis, especially for unfavorable results (CPC 4-5). Transcranial Doppler can continuously monitor patients exhibiting an increased pulsatility index or identified cerebral circulatory arrest waveforms. The integration of various methodologies for dynamic evaluation enhances risk categorization and aids clinical decision-making for patients who attain ROSC. However, these findings are preliminary and require validation in larger cohorts.