The Influence Of Dezocine On The Elderly Patients’ Stress Response To Tracheal Extubation

Objective To study the influence of dezocine on the elderly patients’ stress response to tracheal extubation, and to explore the relationship between dezocine in different doesages and pharmacodynamic actions through a randomized control trial to provide further theoretic basis for the safe and effective clinical use of dezocine.Methods According to inclusion and exclusion criteria, a total of 60 patients undergoing elective laparoscopic gallbladder excision in Mianyang Center Hospital with ASAI-Ⅱ level and age over 60-years were enrolled in this randomized trial. 60 patients were randomly assessed into three groups(Group A, Group B and Group C) by a dedicated nurse anesthetist using the random number table method. All patients were received endotracheal intubation of general anesthesia, and perioperative monitoring was peformed using Mairui Anaesthesia Monitor according to electrocardiogram(ECG), blood pressure(BP), pulse oxygen saturation(Sp O2). After preoxygenation, general anaesthesia was induced using i.v. midazolam 0.5-0.1mg·kg-1 followed by sufentanil 0.2-0.6μg/kg, etomidate 0.3mg·kg-1, vecuronium 50 mg after patients’ consciousness disappeared,,and then inserted a tracheal catheter about 1-2min later. Mechanical ventilation was performed after tracheal intubation, and end-tidal carbon dioxide partial pressure was kept at 35-45 mm Hg,,before surgery beginning, sufentanil 0.3-0.6μg/kg was added to analgesia. Anesthesia was maintained with sevoflurane at minimum alveolar concentration(MAC) of 2-3%, small doses of intravenous infusion of propofol(2-3mg/kg/h), and vecuronium 0.03mg/kg when needed. According to the change of blood pressure and heart rate, adjusting the pumping speed of propofol to maintain the proper depth of anesthesia with stable blood pressure and heart rate. Blinding were also performed by the dedicated nurse, who prepare prescriptions of dezocine and placebo alone without knowing by the anesthetist and patients. Group A were given dezocine 3mg in dilution to 5 ml saline, group B were given dezocine 5mg in dilution to 5 ml saline and group C were given saline 5ml only. Dezocine or placebo intravenous injection were performed when patients’ spontaneous breathing recover at the end of surgery, and patients’ stress response to tracheal extubation were recorded. All patients’ mean arterial pressure(MAP), heart rate(HR), respiratory rate(RR) and pulse oxygen saturation(Sp O2) at the moment of 1min before extubation(T0), extubation(T1) and 5 min after extubation(T2) were recorded. And plasma catecholamine(noradrenaline and adrenaline) levels, cortisol levels were measured by ELISA method at the same three different moments. Visual analogue scale score(VAS score) were performed to evaluate patients with postoperative pain. The awake time, choking cough and agitation while extubating were also recorded.ResultsComparing with group C, mean arterial pressure(MAP), heart rate(HR), the plasma catecholamine(noradrenaline and adrenaline) levels, cortisol levels at T1 and T2 of group B were lower(P<0.05), while no significant difference in respiratory rate(RR) and pulse oxygen saturation(Sp O2)(P>0.05). Comparing with group C, mean arterial pressure(MAP), heart rate(HR), the plasma catecholamine(noradrenaline and adrenaline) levels, cortisol levels at T1 and T2 of group A were little lower, and no significant difference in respiratory rate(RR) and pulse oxygen saturation(Sp O2)(P>0.05). Comparing with group A, mean arterial pressure(MAP), heart rate(HR), the plasma catecholamine(noradrenaline and adrenaline) levels, cortisol levels at T1 and T2 of group B were lower(P<0.05), while no significant difference in respiratory rate(RR) and pulse oxygen saturation(Sp O2)(P>0.05). Given dezocine 5mg in group B could provide a inhibitory effect of awakening agitation while not prolonged postoperative awake. There were no significant difference in awake time in all three groups.Conclusion Using dezocine before tracheal extubation could maintain elderly patients’ hemodynamic stability during extubation and provide a inhibitory effect of awakening agitation while not prolonging postoperative awake and not delaying tracheal extubation.