Pharmacodynamic Interactions of Propofol and Dexmedetomidine on Intravenous Anesthesia

Pharmacodynamic Interactions of Propofol and Dexmedetomidine on Target-controlled Infusion Intravenous Anesthesia During the Induction

The purpose of this study is to determine pharmacodynamic interactions of propofol and dexmedetomidine,exploring the effect of dexmedetomidine on propofol unconsciousness median effective concentration (EC50).

64 cases were randomly divided into four groups, In each group, dexmedetomidine target plasma concentration are 0, 0.4, 0.6, 0.8 ng/ml. Dexmedetomidine administered 15 min before target controlled infusion of propofol. The propofol infusion was started to provide a target effect-site concentration of 1.0ug/ml, and increased by 0.2ug/ml until loss of consciousness when the effect-site concentration and target concentration equilibrium.

Inclusion Criteria:

1. Weight:18≦ BMI≦25
2. Written informed consent from the patient or the relatives of the participating patient.

Exclusion Criteria:

1. A previous history of intolerance to the study drug or related compounds and additives.
2. Existing significant haematological, endocrine, metabolic or gastrointestinal disease.