Transcranial Doppler Ultrasonography as a Complementary Exam in Brain Death Determination: Impact on Protocol Duration and ICU Length of Stay

Background/Objective : Brain death (BD) determination is a critical process in intensive care with significant clinical and logistical implications. Transcranial Doppler ultrasonography (TCD) is accepted as a confirmatory exam for BD in Brazil and several international guidelines, yet its operational impact on protocol efficiency remains poorly characterized. We evaluated whether TCD use is associated with shorter BD protocol duration, reduced ICU length of stay (LOS), and higher organ donation rates. Methods : Retrospective cross-sectional study at a tertiary public ICU in Belo Horizonte, Brazil (December 2017–December 2023). We included 178 patients (≥ 18 years) with completed BD protocols, stratified by complementary exam: TCD (n = 141) or non-TCD (n = 37; EEG and/or angiography). Primary outcome was BD protocol duration (hours); secondary outcomes were ICU LOS (days) and organ donation rate. Negative binomial regression adjusted for age, Charlson Comorbidity Index (CCI), SAPS III, and sex. Results : Groups were comparable in age, CCI, SAPS III, and sex (all p > 0.05). TCD was the only independent predictor of shorter protocol duration: median 9h (IQR 5–23) vs 35h (IQR 20–66); OR 0.45 (95% CI 0.32–0.65); p < 0.001; 54.8% reduction. ICU LOS was also shorter in the TCD group: 4 days (IQR 2–6) vs 5 days (IQR 3–9); OR 0.66 (95% CI 0.51–0.86); p < 0.001; 33.7% reduction. Seventy-five percent of TCD protocols were completed within 24 hours. Organ donation rates did not differ significantly (35% vs 38%; p > 0.05). Conclusions : TCD use was independently associated with substantially shorter BD protocol duration and ICU LOS, supporting broader implementation in institutions with trained practitioners. Organ donation was not associated with TCD use, consistent with its multifactorial nature.