Transcranial Doppler Ultrasonography as a Complementary Exam in Brain Death Determination: Impact on Protocol Duration and ICU Length of Stay-A Single-Center Study in Brazil.

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 post-protocol intensive care unit (ICU) length of stay (LOS), and higher organ donation rates.

METHODS

Retrospective cohort 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 confirmatory exam: TCD (n = 141) or non-TCD (n = 37; EEG or cerebral angiography). Primary outcome was BD protocol duration (h); secondary outcomes were ICU LOS after protocol initiation (days) and organ donation rate. Negative binomial regression adjusted for age, Charlson Comorbidity Index (CCI), Simplified Acute Physiology Score III (SAPS III), sex, calendar year, and protocol opening time (business hours vs. after-hours).

RESULTS

Groups were comparable in age, CCI, SAPS III, and sex (all p > 0.05). TCD use and business hours were the only independent predictors of protocol duration. TCD was independently associated with a 53.9% reduction in median protocol duration [9h (IQR 5-23 h) vs. 35h (IQR 20-66 h); IRR 0.46, 95% CI 0.33-0.65; p < 0.001]. Subarachnoid hemorrhage was more frequent in the non-TCD group (49% vs. 26%; p = 0.015); ischemic stroke was more frequent in the TCD group (28% vs. 11%; p = 0.047). ICU LOS after protocol initiation was shorter in the TCD group [1 day (IQR 1-2 days) vs. 2 days (IQR 2-3 days); IRR 0.51, 95% CI 0.37-0.70; p < 0.001]. Organ donation rates did not differ significantly (35% vs. 38%; p = 0.876).

CONCLUSIONS

TCD use was independently associated with substantially shorter BD protocol duration and post-protocol ICU LOS in a Brazilian tertiary ICU where confirmatory testing is mandatory. These findings support broader TCD implementation in countries with mandatory confirmatory testing requirements, contingent on trained practitioner availability. Generalizability to settings without this requirement is limited.