Advancing Neurological Prognosis in Sepsis: The Vital Role of Transcranial Doppler

In a prospective cohort study, transcranial Doppler identified patients at high risk of sepsis-associated encephalopathy at the bedside.

The day 1 pulsatility index demonstrated an AUC of 0.96, with 95.45% sensitivity and 100% specificity for predicting sepsis-associated encephalopathy. A high day 1 PI reflects increased cerebrovascular resistance and reduced diastolic flow, indicating impaired cerebral perfusion and autoregulation that often precedes clinical encephalopathy.

In a prospective cohort of 93 critically ill septic adults, daily TCD measurements began on ICU day 1. Primary endpoints included SAE incidence, 28‑day mortality, and ICU length of stay. SAE occurred in 44 of 93 patients (47.3%); 28‑day mortality was higher in patients with SAE (61.4% vs 22.4%). Using a day 1 PI cutoff ≥1.30 produced the reported AUC of 0.96, while resistive index (RI) reached peak accuracy on day 3. These data support early TCD measures for prognostic use.

Higher TCD-derived PI and RI correlated with worse clinical outcomes: increasing PI/RI tracked with higher SOFA and APACHE II scores, lower mean flow velocity, greater mortality risk, and increased ICU resource use. The directionality is consistent with cerebral perfusion compromise and impaired autoregulation as plausible mechanisms linking abnormal indices to prolonged ICU care and death. These correlations support prespecified PI/RI thresholds to guide escalation and monitoring decisions.

Key takeaways:

• Pulsatility index measurement on ICU Day 1 identifies SAE risk with near‑perfect diagnostic performance.
• Septic patients admitted from the ED who require ICU care are the primary population affected by early TCD-based risk stratification.