Highly variable pharmacokinetics of dexmedetomidine during intensive care: a case report.
BACKGROUND
Dexmedetomidine is a selective and potent alpha2-adrenoceptor agonist licensed for use in the sedation of patients initially ventilated in intensive care units at a maximum dose rate of 0.7 mug/kg/h administered for up to 24 hours. Higher dose rates and longer infusion periods are sometimes required to achieve sufficient sedation. There are some previous reports on the use of long-term moderate to high-dose infusions of dexmedetomidine in patients in intensive care units, but none of these accounts have cited dexmedetomidine plasma concentrations.


METHODS
We describe the case of a 42-year-old Caucasian woman with severe hemorrhagic pancreatitis following laparoscopic cholecystectomy who received dexmedetomidine for 24 consecutive days at a maximum dose rate of 1.9 mug/kg/h. Samples for the measurement of dexmedetomidine concentrations in her plasma were drawn at intervals of eight hours. On average, the observed plasma concentrations were well in accordance with previous knowledge on the pharmacokinetics of dexmedetomidine. There was, however, marked variability in the concentration of dexmedetomidine in her plasma despite a stable infusion rate.


CONCLUSIONS
The pharmacokinetics of dexmedetomidine appears to be highly variable during intensive care.
Iirola
Timo
T
Department of Anaesthesiology, Intensive Care, Emergency Care and Pain Medicine, University of Turku and Turku University Hospital, FIN-20521, Turku, Finland. tiirola@utu.fi.
Laitio
Ruut
R
Kentala
Erkki
E
Aantaa
Riku
R
Kurvinen
Juha-Pekka
JP
Scheinin
Mika
M
Olkkola
Klaus T
KT