Activated charcoal filtration profoundly alters systemic noradrenaline concentrations during hepatic chemosaturation: A prospective cohort study.

BACKGROUND

Hepatic chemosaturation using extracorporeal circulation (ECC) is associated with severe hemodynamic instability. Activated charcoal filters are used to prevent systemic toxicity, but their effects on circulating catecholamines remain poorly understood.

METHODS

In this prospective, single-center observational study, systemic catecholamine concentrations were measured in 15 procedures undergoing hepatic chemosaturation. Blood samples were obtained at predefined time points: after induction of anesthesia (T0), during initiation of ECC (T1), immediately before (T2.1) and after charcoal filtration (T2.2) and after termination of ECC (T3).

RESULTS

Systemic noradrenaline concentrations changed significantly over time (p < 0.001). The measured noradrenaline concentration increased markedly during inferior vena cava occlusion and ECC. This was consistent with pronounced hemodynamic instability and a significant increase in the dose of noradrenaline administered (T1 and T2.1 vs. T0), followed by a near-complete reduction across the activated charcoal filter (median extraction rate 95.5%) with continued high NA administration (median 0.35 µg/kg/min). In contrast, adrenaline and dopamine concentrations remained stable and were neither administered nor significantly affected by filtration. After termination of ECC, a pronounced rebound increase in noradrenaline concentrations was observed. These biochemical changes were accompanied by metabolic acidosis and rising lactate levels.

CONCLUSION

Activated charcoal filtration during hepatic chemosaturation selectively removes circulating noradrenaline and is a key contributor to perioperative hemodynamic instability. Awareness of this mechanism is essential for tailored vasopressor strategies and safer anesthetic management.

TRIAL REGISTRATION: DRKS, DRKS00034527. Registered 24 June 2024, https://drks.de/search/de/trial/DRKS00034527.