Modulatory effects of dobutamine on hepatic blood flow and systemic haemodynamic parameters during major abdominal surgery: results from an interventional cohort study

BACKGROUND Dobutamine has strong β 1 -adrenergic and β 2 -adrenergic effects. It may directly affect hepatic blood flow (HBF) by altering vascular tone and may also influence HBF indirectly by increasing cardiac index ( CI ), thereby improving regional blood flow. OBJECTIVES This study investigated the dose-dependent effects of dobutamine on HBF, hypothesising that it increases portal vein flow (PVF) and hepatic arterial flow (HAF) via direct, indirect or combined mechanisms. DESIGN Prospective interventional cohort study. SETTING Patients scheduled for pancreaticoduodenectomy in a University Hospital. PATIENTS Thirty patients were included. INTERVENTIONS PVF and HAF were measured using ultrasound transit time (Medi-Stim). HBF, PVF and HAF were indexed to body surface area. PVF and HAF were also analysed in relation to CI . MAIN OUTCOME MEASUREMENTS The primary outcome was HBF at baseline (T1), after administration of dobutamine 2 μg kg −1 min −1 (T2), and 5 μg kg −1 min −1 (T3). The secondary outcome was to evaluate systemic haemodynamic variables at the corresponding time points. RESULTS Data from 30 patients were analysed. Dobutamine resulted in a mean predicted increase in CI of 0.26 ml min −1 m −2 (T2) and 0.41 ml min −1 m −2 (T3) ( P < 0.05). Total HBFi increased in a dose-dependent manner, with a predicted increase of 49 ml min −1 m −2 (T3) ( P < 0.05). PVFi showed a predicted mean increase of 38 ml min −1 m −2 (T2) and 87 ml min −1 m −2 (T3), and relative PVFi exhibited a predicted mean increase of 1.2% (T3) ( P < 0.05). However, HAFi declined with a predicted decrease of 38 ml min −1 m −2 (T3), while relative HAFi showed a mean predicted decrease of 0.8% (T2) and 1.7% (T3) ( P < 0.05). CONCLUSION Dobutamine administration led to dose-dependent increase in CI . Total HBFi and PVFi increased, while HAFi decreased. At higher doses, relative PVFi also increased, while relative HAFi declined. TRIAL REGISTRATION Study protocol EC: BC-08919 (06/04/2021); FAGG approval: (18/03/2021); EudraCT n°: 2020-005412-21 (01/02/2021); Clin.trial.gov: NCT04893655 (30/04/2021).