Efficiency of different dose dexmedetomidine combined with remifentanil and propofol in controlled hypotension of nasal endoscopic surgery

doi:10.3969/j.issn.1002-7386.2018.04.013

Abstract：Objective To observe the effects of different dose dexmedetomidine combined with remifentanil and propofol in controlled hypotension of nasal endoscopic surgery. Methods A total of 120 patients who would receive nasal endoscopic surgery in our hospital were randomly divided into group A,group B,group C and group D,with 30 patients in each group.All the patients were given propofol 2mg/kg by intravenous injection, atracurium 0.6 ~1.0mg/kg and remifentanil 2μg/kg for induction of anaesthesia, and general anesthesia was maintained with propofol 4 ~ 8mg·kg-1·h-1and remifentanil 0.25μg·kg-1·min-1. Before induction of anaesthesia the patients in group B,group C and group D were given dexmedetomidine of 0.5μg/kg,0.8μg/kg,1.0μg/kg,respectively, then keeping anaesthesia effects with dexmedetomidine 0.5μg·kg-1·h-1until the end of surgery,however,the patients in group A were given the same volume of 0.9% sodium chloride solution. The mean arterial pressure(MAP) and heart rate(HR) of patients were detected before injection(T0),at 5 min (T1) and 30 min (T2) after blood pressure dropping to target,at 10 min(T3), 30 min(T4)and 60 min(T5)after intubation. The quality of surgical field at T1 and T2 was evaluated by Fromme surgical field quality scoring.The sedation state and and pain status at T3,T4,T5 were evaluated by Ramsay and VAS pain score.Moreover the time of controlled hypotension, postoperative spontaneous breathing recovery time, awakening and extubation time were recorded. In addition the incidence rates of postoperative distending pain of nose,delirium,restlessness and shivering were observed and compared among the four groups.Results As compared with those at T0, the HR and MAP in group A were significantly increased at T1 and T2, however,which in groups B,C,D were significantly lower than those in group A(P<0.05).Moreover the HR and MAP in groups C and group D were significantly lower than those in group A at T3,T4,T5 (P<0.05). As compared with those in group A,the Fromme scores and VAS scores in group B,C and D were significantly decreased(P<0.05),however,Ramsay scores were significantly increased (P<0.05). The time of awakening and extubation time in group C and group D were significantly longer than those in group A (P < 0. 05). In addition there were no significant differences in controlled hypotension time and postoperative spontaneous breathing recovery time among groups (P>0.05). Moreover the incidence rates of distending pain of nose,delirium,restlessness and shivering in group B,C and D were significantly decreased,as compared with those in group A (P<0.05). Conclusion The dexmedetomidine combined with remifentanil and propofol controlled hypotension for patients receiving nose endoscopic surgery can effectively improve the operation field and enhance the palinesthesia quality after anesthesia,in which dexmedetomidine 0.5g/kg is an appropriate clinical dose.