Clinical Research Of Dexmedetomidine Hydrochloride For Anesthesia Extubation

Objective:The right of dexmedetomidine hydrochloride in the role of anesthesia extubation, and to explore the optimal dose of its clinical application.Methods:Select intravenous and inhalation anesthesia in patients undergoing elective surgery under the 160 cases, aged 18 to 65 years of age; 83 males,77 females; weight (kg) in the standard body weight±20%; all cases there was no severe preoperative hypertension, liver and kidney dysfunction, endocrine and nervous system disorders. Anesthesia was induced with midazolam 0.05mg/kg, propofol 1.5-2mg/kg, fentanyl 2 4μg/kg and vecuronium 0.1mg/kg. Intraoperative infusion of propofol 4-10mg/kg/h, intermittent intravenous vecuronium 0.04mg/kg and fentanyl 0.05-0.1mg to maintain anesthesia, inhalation of 1 to 2% isoflurane until skin closure, patients no use of antiemetic drugs, surgery before the end of 30min no use of muscle relaxants and analgesics, the end of surgery were transferred to PACU.Into the PACU patients were randomly divided into 4 groups:control group, propofol (P group) and test group (D group), experimental group was divided into D1, D2, D3 three subgroups,40 cases in each group.P group of target-controlled infusion of propofol, plasma concentration is set to 1μg/ml; D1 group, D2 group, D3 DEX group were given a loading dose 0.3μg/kg,0.5μg/kg,0.7μg/kg, 10min by slow intravenous injection pump, the maintenance dose were 0.3μg/kg/h, 0.5μg/kg/h,0.7μg/kg/h; patients resumed spontaneous breathing was discontinued. Each blood pressure (BP), heart rate (HR), pulse oxygen saturation (SpO2), bispectral index (BIS), cardiac (ECG), end-tidal carbon dioxide partial pressure (PETCO2), end-expiratory anesthetic concentration, urine volume, body temperature, blood gas analysis is routine monitoring. Patients transferred to PACU with ventilator control ventilation, inspired oxygen concentration 60%, tidal volume 8-lOml/kg, respiratory rate 10 to 12 times/min, maintained PETCO2 at 35-45mmHg, end-tidal anesthetic concentration was reduced to 0.2% Time to stop mechanical ventilation, use of manual respiration until the patient resumed spontaneous breathing. Extubation in patients with indications for extubation to meet standards from the room to switch out the PACU. SBP, DBP, HR and BIS of patients were drawn following 7 time points:preoperatively (TO), immediately transferred to PACU (before administration, T1), after administration 10min (T2), end-tidal anesthetic concentration was reduced to 0.2%(T3), spontaneous breathing (T4), Suction extubation (T5), after extubation lOmin (T6), turn out the PACU immediately (T7). Extubation in patients with cough response was observed. Patients with end-tidal anesthetic concentration was reduced to 0.2% of the time, spontaneous breathing recovery time, call time to eye opening, extubation time, visual analog score (visual analogue scale, VAS), and PACU stay were recorded. Respiratory depression, hypertension, hypotension, tachycardia,bradycardia, nausea, vomiting, chills, and restlessness were observed. Spss13.0 software was used for statistical analyses. Group at each time point were analyzed by ANOVA, the same time point between groups paired t test was used to compare, count data were analyzed byχ2 test, P<0.05 considered statistically significant difference.Results:Four groups of patients in gender, age, height, weight, type of surgery, operative time, end-tidal anesthetic concentration decreased to 0.2% of the time so there was no significant difference (P>0.05). Compared with TO, P group of SBP, DBP in the T5, HR was significantly higher in T5 and T6 (P<0.05); D1 group of SBP, DBP in the T5, HR at T5 and T6 were significantly increased (P<0.05); D2 group at each time point compared with TO was no significant difference (P>0.05); D3 group of SBP in the T2, DBP increases in T2-5, HR slowed down in the T2-4 (P<0.05). And the P group, D1 group at each time point SBP, DBP and HR with no significant difference between P group (P>0.05), BIS T2-4 was higher than in P group, spontaneous breathing, call eyes, extubation and PACU stay was significantly shorter (P<0.05), extubation quality with no statistically significant difference (P>0.05); D2 group of SBP, DBP, HR at T5, T6 were significantly decreased, BIS in T4 higher than the P group, spontaneous breathing recovery time, calls for open eyes and PACU stay was significantly shorter, VAS decreased extubation quality is better than P group, extubation rate of hypertension (P<0.05); D3 group The SBP, DBP transient increase in T2, T5 lower, HR slowed down in the T2-6, BIS in T2-4, T6 significantly lower than the P group was significantly shorter recovery time of spontaneous breathing, extubation time extension, VAS decreased extubation quality is better than P group (P<0.05). Compared with the D1, D2 group of SBP, DBP in the T5, T6 were significantly decreased, HR decreased in the T4-6, BIS in group T2-4 less than D1, D1 extubation quality is better than group, extubation rate of hypertension (P<0.05); D3 group SBP increased in the T2, T5 lower, DBP decreased in the T5, HR decreased in T2-6, BIS in T2-4, T6 lower, calls for open eyes, extubation, and PACU stay were prolonged, the quality is better than Dl extubation group (P<0.05). Compared with the D2, D3group of SBP, DBP increases in T2, HR decreased at T2, BIS in T2-4, T6 reduced call time to eye opening, extubation, and PACU stay for a longer (P<0.05), extubation quality showed no significant difference (P>0.05).Conclusion:1.DEX possess a dose-dependent sedation, analgesia, anesthesia extubation patients can process more stable hemodynamics, and reduce the cough response, reduce postoperative pain and improve the quality of extubation.2.0.5μg/kg of DEX sedation moderate, stable hemodynamics, mild cough, pain is better, fewer complications, does not affect the recovery time, more suitable for extubation anesthesia application.