Utility of transcranial Doppler and reversed jugular venous saturations for neuromonitoring in children with acute liver failure.

Paediatric Acute Liver Failure (PALF) is associated with high morbidity and mortality, with cerebral oedema a key contributor to mortality. The aim of our study was to examine the association between the findings of two neuromonitoring modalities (transcranial Doppler (TCD) and reverse venous jugular oxygen saturation (SjvO2) and mortality, as well as ammonia levels, in children with acute liver failure who received neuroprotection within 7 days of paediatric intensive care unit (PICU) admission. Retrospective observational cohort study. Sixteen-bed PICU in a UK university-affiliated tertiary care hospital. Patients admitted to the PICU with PALF were reviewed between January 2013 and October 2023. Seventy-eight children, who were intubated and ventilated, had neuromonitoring either with TCD/SjvO2 or both during the first week of hospital admission (before liver transplantation), and were included in the study. INTERVENTIONS: None. The median (IQR) age of the study population was 64 (25-144) months. Among the 78 children, 24 (30.8%) survived without liver transplant, 39 children (50.0%) survived post-liver transplant, 5 (6.4%) died post-transplant, and 10 (12.8%) died without transplant. Patients who died had a lower meanvelocity in the right middle cerebral artery (RMCA Vm) (Median: 34 cm/s vs 55 cm/s, p-value: 0.01) and higher pulsatility index (PI) than those who survived (Median: 2.1 vs 1.6, p: 0.001). SjvO2 was also lower in non-survivors than in survivors (Mean: 39.0% vs 56.1%, p-value: 0.002). The PI had a weak positive correlation with ammonia (Rho: 0.25, p: 0.005). RMCA Vm and SjvO2 had a negative correlation with ammonia (Rho: - 0.21, p-value: 0.022; Rho - 0.22; p-value: 0.017 respectively). CONCLUSION: Patients with acute liver failure who died had a high RMCA PI, lower RMCA Vm, and lower SjvO2. TCD and SjvO2 may serve as useful adjuncts to the overall neurological assessment in critically ill children with PALF. WHAT IS KNOWN: • Paediatric Acute Liver Failure (PALF) is associated with high morbidity and mortality, with cerebral oedema a key contributor to mortality. • There is little published evidence regarding the use of bedside neuromonitoring techniques like transcranial dopplers and reverse jugular saturations in the paediatric population with acute liver failure. WHAT IS NEW: • In our single-centre experience (2013-2023), neuromonitoring in PALF patients correlates with mortality. Bedside neuromonitoring with TCD and SjvO2 showed a weak correlation with ammonia and between each other. • Future work should focus on the impact of neuromonitoring on delivered neuroprotective strategies and patient outcomes.