Reliability of serum catecholamine concentrations in reflecting depth of dexmedetomidine-based general anesthesia / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the reliability of serum catecholamine concentrations in reflecting the depth of dexmedetomidine-based general anesthesia.Methods Forty patients,aged 30-45 yr,of American Society of Anesthesiologists physical status Ⅰ-Ⅱ,undergoing elective laparoscopic hysterectomy under general anesthesia,were divided into 2 groups (n =20 each) using a random number tabledexmedetomidine-based general anesthesia group (group Ⅰ) and general anesthesia group (group Ⅱ).Dexmedetomidine was intravenously infused as a loading bolus of 1 μg/kg over 10 min before induction of anesthesia,followed by an infusion of 0.5 μg · kg-1 · h-1 until 30 min before the end of operation in group Ⅰ.The equal volume of normal saline was given instead of dexmedetomidine in group Ⅱ.Anesthesia was induced with iv midazolam 0.05 mg/kg,propofol 1 mg/kg,cisatracurium 0.15 mg/kg and sufentanil 0.4 μg/kg.Anesthesia was maintained with iv infusion of remifentanil 0.1-0.3 μg · kg-1 · min 1,1％-2％ sevoflurane inhalation and intermittent iv boluses of cisatracurium.Before administration of dexmedetomidine,at the end of administration of the loading dose,at the end of intubation,at the end of skin incision,after establishment of pneumoperitoneum and at the end of operation (T0-5),venous blood samples were taken from the peripheral vein for determination of concentrations of epinephrine (E) and norepinephrine (NE) in serum (by enzyme-linked immunosorbent assay).Results Compared with group Ⅱ],the serum NE and E concentrations were significantly decreased at T1-4 in group Ⅰ (P＜0.05).Compared with the baseline at T0,the serum NE and E concentrations were significantly decreased at T1 in group Ⅰ,and increased at T2-4 in group Ⅱ (P＜0.05).Conclusion The serum catecholamine concentration produces poor reliability in reflecting the depth of dexmedetomidine-based general anesthesia,and thus it is not a suitable monitoring index.