Dobutamine-induced alterations in internal carotid artery blood flow and cerebral blood flow in healthy adults.

PURPOSE: Dobutamine, a sympathomimetic agent, is widely used clinically, influencing cardiac output, heart rate (HR), and blood pressure (BP), which may impact cerebral blood flow (CBF), critical for brain metabolism. However, the effects of dobutamine on CBF and internal carotid artery (ICA) blood flow remain unclear, with contradictory reported in both clinical and animal studies. It is necessary to investigate the effects of dobutamine on cervical and cerebral hemodynamics. This study aimed to evaluate the effects of dobutamine infusion on ICA blood flow and CBF, explore their relationship, and identify factors influencing CBF to facilitate timely monitoring in clinical practice.

METHODS

Forty-eight healthy volunteers underwent physiological assessment, ICA ultrasound, and brain magnetic resonance imaging (MRI) data before and after the administration of dobutamine. Paired t and Wilcoxon signed-rank tests were used to analyze changes, while logistic regression explored associations between hemodynamic factors and CBF.

RESULTS

Dobutamine infusion significantly increased HR, respiration rate, systolic BP (SBP), diastolic BP (DBP), and mean arterial pressure, while blood oxygen remained stable. Compared with those in the resting state, the peak systolic velocity (Vs), resistance index, pulsatility index, and systolic/diastolic ratio (S/D) increased, whereas end-diastolic velocity (Vd) decreased. ICA diameter and mean velocity showed no significant changes. CBF significantly decreased in the anterior and middle cerebral arteries. Logistic regression identified SBP, DBP, and S/D difference as key factors associated with CBF reduction.

CONCLUSIONS

Dobutamine altered ICA hemodynamics and reduced CBF in anterior and middle cerebral arteries. Real-time ICA ultrasound monitoring provides valuable guidance during clinical use.