Prolonged use of dexmedetomidine in an infant with respiratory failure following living donor liver transplantation.

We used dexmedetomidine for more than 2 months in a mechanically ventilated infant without serious adverse effects. An infant with liver cirrhosis of unknown cause underwent living donor liver transplantation at the age of 9 months. Long-term mechanical ventilation was required postoperatively, and midazolam with fentanyl had been used to sedate the patient. They required increase to 1.7 mg.kg(-1).h(-1) and 3.5 microg.kg(-1).h(-1), respectively, which were still inadequate. On postoperative day 29, dexmedetomidine was added. The rate of dexmedetomidine infusion was increased gradually to 1.4 microg.kg(-1).h(-1). It was discontinued temporarily to exclude drug-induced liver dysfunction. However, without dexmedetomidine, adequate sedation level was unattainable. Liver dysfunction was likely to be attributed to cytomegalovirus infection and after restarting dexmedetomidine, the respiratory condition improved. He was extubated 10 weeks after the operation. Dexmedetomidine was successfully tapered off over the following 2 weeks with no signs of withdrawal. Dexmedetomidine was a useful sedative for an infant who required mechanical ventilation for a prolonged period of time.