Changes of dorsalis pedis artery flow pattern after caudal block in children: observational study using a duplex sonography.

OBJECTIVE: To evaluate the changes of the flow velocity, the volume flow, and the diameter of dorsalis pedis artery using a duplex ultrasonography after caudal block with sevoflurane anesthesia in children. AIM: To know the acute change in peripheral arterial flow patterns of sympathetically blocked lower limbs in anesthetized children. BACKGROUND: Caudal analgesia in combination with general anesthesia may affect the circulatory hemodynamics due to sympatholytic vasodilating effects. METHODS: After approval by the Ethics Committee, we evaluated the changes of peripheral hemodynamics using a duplex ultrasonography before and after a caudal block in sevoflurane-anesthetized children. RESULTS: A caudal block using 0.15% ropivacaine 1.5 ml·kg(-1) significantly altered the arterial flow patterns; increased peak velocity (24%) and volume flow (76%), and the diameter of the dorsalis pedis artery (20%) in children. However, blood pressures and heart rates were not affected significantly by caudal block. CONCLUSIONS: Duplex sonographic measurements indicate that a caudal block changes the flow patterns of the dorsalis pedis artery significantly in the anesthetized children.ope