Climical Study On The Application Of Dexmedetomidine Hydrochloride In Thorcic Surgery

Objective:Dexmedetomidine hydrochloride is a new type of high selective a2 adrenergic receptor agonists, has analgesic, sedative and anxiolytic effects, can reduce the amount of anesthetic, to maintain hemodynamic stability, reducing the hemodynamic response to intubation, surgery stimulation, extubation, and inhibiting the stress response. This test is designed to observe the effects of different doses of dexmedetomidine in patients scheduled for thoracic surgery analgesic sedative effects, and on hemodynamics, cortisol, glucose, and to explore the clinical effects and dose relationship for provide a basis for clinical application.Methods:Select 120 patients who are ASAⅠ-Ⅱ-class selective inhalation general anesthesia in thoracic surgery, aged 18 to 65 years old, weighing 45～85kg, body mass index of 20～25kg/m2, all patients without severe high blood pressure, heart and liver renal dysfunction, endocrine and nervous system diseases. Randomly divided into three groups (D1～D3) experiment, each group 40 cases, D1, D2, D3 group after the burglary, loading dose of 0.4μg/kg,0.6μg/kg, 0.8μg/kg dexmedetomidine and pumping it using micropump 10min, then pumping the dose of 0.4μg/kg/h,0.6μg/kg/h,0.8μg/kg/h dexmedetomidine continuous through intravenous pump to one hour after the beginning of surgery. Determined to dexmedetomidine after induction, both groups were intravenous midazolam 0.02～0.05mg/kg, vecuronium 0.08～0.12mg/kg, propofol 1.5 mg/kg, sufentanil 0.4～0.6μg/kg during induction, patients inhaled 2%to3%of sevoflurane, according to intraoperative monitoring necessary to give sufentanil 0.1μg/kg, vecuronium 0.03mg/kg, when skin closure stop sevoflurane, any medicine will not be given 30 min before the end of the surgery, and any antiemetic drugs are not given. Routine monitoring of patients in each group SBP, DBP, MAP, HR, SPO2, PETCO2 and end-tidal sevoflurane concentration was observed burglary, when three groups of patients got in the operating room(before dexmedetomidine be given) (TO), immediately before intubation (T1), immediately after intubation (T2), after intubation 3 min (T3), before cut the skin (T4), spontaneous breathing is restored (T5), suction time (T6), immediate extubation (T7), extubation after 5 min (T8), recorded the systolic blood pressure (SBP), diastolic blood pressure(DBP),mean arterial pressure (MAP),heart rate(HR), pulse oxygen saturation(SpO2), and in TO-T8 patients with arterial blood collected at each time point measurement of corticosteroid and glucose. Presented fornormal circadian rhythm of cortisol secretion and plasma cortisol have the highest concentrations in the morning, and to 10μg/(L·h) speed decrease, so all patients were selected the first of elective surgery in the morning. Also recorded body movement, cough reflex, respiratory depression, hypertension, hypotension, tachycardia, bradycardia, and after extubation, nausea, vomiting, chills, and restlessness and other adverse reactions were observed. Used SPSS13.0 statistical software for statistical processing, measurement data using mean±standard deviation, which was used to compare data within groups repeated measure analysis of variance, between groups of data were compared with paired t test, p<0.05 for the difference was statistically significant.Result: Three groups in gender, age, weight, operation time and so the difference was not statistically significant (P> 0.05), when they got into the operating room and when started pumping the drugs, the basic vital signs were no statistical significant difference (P> 0.05). There was no difference among three groups of patients with intubation and extubation period of little change in pulse oxygen saturation (P> 0.05). Comparison among groups:in D1 group, the fluctuations of SBP, DBP, MAP and HR was significantly greater than that of D2 and D3 groups, moreover, in D1 group, Cor, Glu inhibitory concentration is less than that of D2 and D3 groups, the difference was statistically significant(P<0.05). Comparison within groups:fluctuations of intubation and extubation of hemodynamic is much bigger in D1 group, but that in other two groups are smaller (P>0.05). Furthermore, the D3 group had 2 cases of hypotension, and 7 cases of hypertension, and the extubation time is quite longer than D2 group, which make dramatic differences between those two groups (P<0.05). In D1, D2 and D3 group, Cor concentration is higher in time point T8, in addition, the Glu concentration in D1 group is significantly higher at T8 time (P<0.05).Conclusion:1. Dexmedetomidine hydrochloride has a dose dependent analgesic given sedation effect. This medicine makes hemodynamics of patients more stable, reduces the stress response, stables the induction of anesthesia and extubation in the operation of thoracotomy.2. The 0.6μg/kg dose of dexmedetomidine hydrochloride can make hemodynamic more stable, inhibit the stress response, reduce adverse events, without affecting the awakening and extubation time of patients. In conclusion, this medicine is suitable for patients with thoracic anesthesia Anesthetic adjuvant.