Effects Of Dexmedetomidine On Cough Reflex And Postoperative Recovery In Patients Undergoing Thyroid Surgery

Objectives To evaluate the effect of dexmedetomidine on cough reflexand postoperative recovery in patients undergoing thyroid surgery.Methods Approved by the hospital ethics committee,from December 2015 to June 2016 in our hospital patients with thyroid tumor surgery for the study,the trial began before all patients were informed consent.118 patients aged 18 to 64 yr,BMI 18 30 kg/m² and ASA grade ? below were selected and randomly divided into 2 groups?n=59 each?: dexmedetomidine group?group D?and control group?group C?.Anesthesia was induced with iv injection of midazolam,propofol,sufentanil and vecuronium.The patients were mechanically ventilated after tracheal intubation.Anesthesia was maintained with propofol and remifentanil infusion.At the beginning of the operation,patients in group D were infused with dexmedetomidine at a rate of 0.4 ?g·kg^-1·h^-1 until the end of surgery.Group C were infused with the equal volume of normal saline.The incidence and severity of coughing during recovery,the volume of drainage at first and second 24 h after surgery,mean arterial pressure?MAP?and heart rate?HR?before induction of anesthesia?T0?,at the end of surgery?T1?,the time of suctioning?T2?,the time of extubation?T3?,and at 5,10 and 15 min after extubation?T4-6?,the dosage of anesthetics,the time of operation and anesthesia,respiratory restoration,extubation,PACU residence,the score by 40-item quality of recovery sowing system at preoperative,24 h,48h,3 months and 6 months post-operation,the postoperative length of stay,the occurrence of adverse events,the incision healing level,satisfaction of patients,tumor metastasis and recurrence at 3 months and 6 months postoperatively were recorded respectively.Results There was no significant differences of baseline data between the two groups,including ratio of gender,age,BMI,ratio of ASA,hypertention history,diabetes history,the duration of operation and anesthesia,the result of intraoperative biopsy,total scores of the QOR-40 at preoperative?P>0.05?.Compared with group C,the incidence and grade of coughing were lower in group D?P<0.05?.The volume of drainage at first and second 24 h after surgery were lesser of group D than group C?P<0.05?.Compared with group C,the MAP and HR were significantly decreased at T2-4 in group D,the incidence of tachycardia during recovery was decreased?P<0.05?.Compared with group C,the dosage of propofol and remifentanil were lower in group D?P<0.05?.The group D has more scores of the QOR-40 in emotional state,physical comfort,pain and total scores at 24 h after surgery.Compared with group C,satisfaction of patients during hospitalization improved in group D.There was no significant difference in the time of respiratory restoration,extubation,PACU residence,the postoperative length of stay and the incision healing level between the two groups?P>0.05?.There was no significant difference in the scores of the QOR-40,satisfaction of patients,tumor metastasis and recurrence at 3 months and 6 months postoperatively between the two groups?P>0.05?.Conclusions?1?Continuous infusion of dexmedetomidine at a rate of 0.4 ?g·kg^-1·h^-1 in patients undergoing thyroid surgery with general anesthesia can relieve cough reflex.?2?Continuous infusion of dexmedetomidine at a rate of 0.4 ?g·kg^-1·h^-1 can keep stable perioperative hemodynamics,reduce the risk of the postoperative bleeding,improving the early quality of recovery and have no effect on long-term postoperative recovery in patients undergoing thyroid surgery with general anesthesia.