A high dose of dexmedetomidine using the BIS monitor™ for diagnostic and interventional cardiac catheterization in a toddler with congenital heart disease.

Dexmedetomidine (DEX) for sedation in diagnostic and interventional cardiac catheterization (DICC) has been reported to require other drugs or rescue drugs because of its insufficient sedative effect when used alone. We administered DEX and adjusted its dose according to the bispectral index (BIS) monitor™ for DICC in a toddler; consequently, a high dose of DEX had to be administered. The patient was a 1-year and 4-month-old boy who was scheduled to undergo DICC after intracardiac repair. We used DEX alone as the sedative because this was expected to avoid oxygen supply and mechanical ventilation and to produce a safe situation for procedures around the neck. DEX was administered at the dose of 1-15 μg/kg/h according to BIS monitor™; administration of cardiovascular drugs or oxygen supply or assist ventilation, except chin lift, were not needed. The maximum predicted plasma concentration (pCp) of DEX and mean pCp were calculated as 6.1 and 4.1 ng/mL, respectively. A high dose of DEX may be required for DICC sedation, as for MRI sedation, in many cases. Although further studies should be conducted to reveal the merits and demerits of DEX in cardiac catheterization, a high dose of DEX may be useful in some cases.