The Effect Of Dexmedetomidine On Stress Response In Patients Undergoing Endoscopic Retrograde Cholangiopancreatography

ObjectiveTo evaluate the effect of dexmedetomidine on stress response in patients undergoing endoscopic retrograde cholangiopancreatography(ERCP). Methods80 patients undergoing elective ERCP under intravenous anesthesia were randomly divided into test group(group T,n = 40) and control group(group C,n = 40). In group T, patients received continuous intravenous 1?g· kg-1 dexmedetomidine for 10 min, then intravenous anesthesia was performed with dexmedetomidine 0.5?g· kg-1· h-1 dexmedetomidine intravenous infusion combined with propofol TCI. In group C, patients were sedated with continuous intravenous midazolam 0.02mg· kg-1 for 10 min, then intravenous anesthesia was performed with propofol TCI. The initial target plasma concentration of propofol was setted at 3.0?g/ml in both groups, The propofol effect-site concentration was measured when eyelash reflex in patients disappeared, and then increase the concentration of the propofol effect-site to 1.5~1.7?g/ml as the target concentration of propofol during the entering of mirror and the surgery. The depth of anesthesia was adjusted according to the physical activities of the patients in both two groups.Heart rate(HR), Systolic pressure(SBP), Diastolic pressure(DBP), mean arterial blood pressure(MAP), pulse oxygen saturation(SPO2) and plasma glucose were recorded before operation(T0), at the time of the eyelash reflex disappeared(T1), mirror entered(T2),the Oddi sphincter was cut open(T3), and the mirror was withdrew(T4). Propofol effect-site concentration at the time of T1 to T4 and anesthesia recovery time in both groups were also recorded. Repeated Measures Analysis of Variance was used to test difference between the two groups and difference among time points, and Bonferroni t test was used to test difference between the two groups at a certain time. ResultsCompared with T0, HR in Group T had a downward trend, while HR in Group C had a rising trend,but there was no significant difference at different time points in both Groups(P>0.05).Compared with group C, HR at T1 to T4 in group T were significantly decreased(P<0.05). SBP and DBP were significantly decreased at T1 to T4 in both groups compared with that at T0(P <0.01). MAP was significantly decreased at T1 to T4 in both groups compared with that at T0(P <0.05). There was no significant difference of SPO2 at different time points in both groups and also no significant difference in both groups(P>0.05). Plasma glucose was significantly decreased at T1 to T3 in both groups compared with that at T0(P <0.05), but there was no significant difference between both two groups(P>0.05). Propofol effect-site concentration at T1 to T4 were significantly lower in Group T than that in Group C(P<0.01). Anesthesia recovery time in Group C was significantly shorter than that in Group T(P<0.05). ConclusionAnesthesia with dexmedetomidine or midazolam combined with propofol TCI can reduce stress response in patients undergoing elective ERCP. However, anesthesia with dexmedetomidine combined with propofol TCI has obvious advantages in lowering cardiovascular response and reducing propofol dosage than midazolam.