Effects Of Dexmedetomidine On Tracheal Extubation Responses Of Patients Undergoing Abdominal Surgery After General Anethesia

Objective:The purpose of this study is to investigate the effects of dexmedetomidine on extubation responses after general anethesia, including cardiovascular responses, respiration, sedative effects, analgesic effects and BIS index.Methods:48 patients, ASA physical statusⅡ-Ⅲ, aged 18-65 years old, had been chosen undergoing selective abdominal operations.24 patients(No hypertention history and blood pressure was normal when entering operating room) were divided into two groups randomly:Group P1 (patients received 10ml saline, n=12) and Group D1 (patients received dexmedetomidine 0.6μg/kg, n=12);②And 24 patients (mild high blood pressure when entering operating room) were divided into two groups randomly,Group P2 (patients received 10ml saline, n=12) and Group D2 (patients received dexmedetomidine 0.6μg/kg, n=12).After the anesthetic induction and tracheal intubation,the patients were ventilated by IPPV in pure oxygen. Anesthesia was maintained by propofol, sevofluence and atricurium. About 30 minutes before the surgery finished, dexmedetomidine 0.6μg/kg or 10ml saline was administered with TCI over 10 minutes. When the surgery finished, stopped all the anesthetic drugs. Patients were observed in PACU before the patient's Aldrete score was over 9.Systolic blood pressure (SBP), diastolie blood pressure (DBP), heart rate (HR), BIS Index, respiratory rate (RR) and SPO2 values were recorded at the time of premeditation, dexmedetomidine or saline injection; 1,3,5,10,15,30 minutes after the dexmedetomidine or saline injection; during tracheal extubation and 1,3,5,10,15,30,60min after the tracheal extubation. Rate-pressure product was derived from SBP*HR. Besides these, Recorded visual analogue scale value (VAS), fisrt analgesia time after the surgery, O/AAS score and adverse effects.Results:(1) At the tracheal extubation or 1,3,5 minutes after the tracheal extubation, the SBP, DBP, HR, RPP of the patients in Group D1 decreased significantly compared with those in group P1 (P<0.05); The SBP, HR, RPP in group D2 decreased significantly compared with those in group P2 (P<0.05). (2) The VAS value of group D was lower than group P (P<0.05). As for the fisrt analgesia time after the surgery, group D's was longer than group P's (P<0.05), that showed statistic significance.Conclusion:(1) Dexmedetomidine of 0.6μg/kg may effectively control cardiovascular responses of patients to the tracheal extubation, neither respiratory depression, nor prolonging recovery had happened. (2) Besides these, dexmedetomidine of 0.6μg/kg may have some analgesic effects.