基于VAS评价右美托咪定在宫颈癌根治术后镇痛及术后快速康复中的临床效果

目的:研究右美托咪定在宫颈癌根治术后镇痛及术后快速康复中的临床应用效果。方法:将2015年7月至2018年7月在本院行宫颈癌根治术的86例患者随机分为对照组和观察组各43例。对照组术后镇痛采用舒芬太尼和格拉司琼，观察组术后镇痛加用右美托咪定。采用视觉模拟评分法（VAS）评价患者术后1 h、6 h、12 h、24 h、48 h疼痛情况，采用Ramesay评分法评价患者不同时间点镇静状况，记录并比较两组患者不同时间点收缩压、舒张压、心率及呼吸频率变化，比较两组患者不良反应发生情况。结果:观察组患者术后6 h、12 h、24 h、48 h VAS评分均明显低于对照组（P＜0.05），Ramesay评分均明显高于对照组（P＜0.05）；观察组和对照组患者术后不同时间点呼吸频率比较，差异无统计学意义，但术后6 h、12 h、24 h观察组患者收缩压、心率均明显低于对照组（P＜0.05），术后1 h、6 h观察组患者舒张压明显低于对照组（P＜0.05）；观察组患者恶心呕吐、高血压发生率较对照组明显减低。结论:右美托咪定用于宫颈癌根治术后镇痛，可以提高镇痛镇静效果，稳定患者血流动力学，有助于术后快速康复。     

Mivazerol, a new α2-adrenergic agonist, blunts cardiovascular effects following surgical stress in pentobarbital-anesthetized rats

Background: Mivazerol is a new and selective α₂-adrenoceptor agonist, devoid of hypotensive effects, which has been designed to prevent adverse cardiac outcome in perioperative patients with, or at risk of coronary artery disease. Methods: In the present study, the effects of mivazerol on hemodynamic changes induced by trachea-exposure surgery stress were investigated in pentobarbital-anesthetized rats, and compared to those of dexmedetomidine. Results: Intravenous infusion of 3 different doses of mivazerol (3.75, 7.5 and 15 μg kg^-1 h^-1) did not significantly alter BP but caused a dose-related decrease in HR. The maximal decrease in HR was approximately 87 beats/min. Contrary to mivazerol, dexmedetomidine (7.5 μg kg^-1 h^-1, i.v.) decreased both BP (11±3.2 mmHg) and HR. The maximum decrease in HR was approximately 104 beats/min. Surgical stress produced a rapid increase in BP (maximal increase of 50 mmHg) and HR (maximal increase of 100 beats/min), which lasted for at least 15 min. Constant infusion of mivazerol, at a dose of 15 μg kg^-1 h^-1, beginning 20 min prior to surgery and lasting for 35 min, significantly inhibited surgical stress-induced increases in BP (P < 0.05) and HR (P < 0.001). Dexmedetomidine, at a dose which produced hypotension and profound bradycardia prior to surgery, did not have any effect on the surgical stress-induced elevation in BP (P>0.05), but prevented the increase in HR (P < 0.05). Pretreatment with the α₂-adrenoceptor antagonist rau-wolscine (0.5 mg/kg, i.v.) blocked the bradycardia induced by mivazerol as well as the inhibitory effect of mivazerol on surgical stress-induced elevations in HR and BP. Conclusion: Mivazerol attenuates surgical stress-induced elevations in BP and HR during pentobarbital anesthesia in rats, and these effects are mediated by stimulation of α₂-adrenoceptors. Unlike dexmedetomidine, mivazerol does not reduce BP, and is also more potent than dexmedetomidine in blunting surgical stress-induced increases in BP in pentobarbital-anesthetized rats.     

Transfer of clonidine and dexmedetomidine across the isolated perfused human placenta

Background: The placental transfer of the a₂ receptor agonist clonidine, earlier used as an adjuvant in obstetric epidural analgesia, was compared with the transfer of the newer and more %-selective agonist dexmedetomidine.
Methods: Term placentas were obtained immediately after delivery with maternal consent and a 2-hour recycling perfusion of a single placental cotyledon was performed. Disappearance from the maternal circulation, accumulation in placental tissue and appearance in the fetal circulation of clonidine or dexmedetomidine with the reference compound antipyrine were followed in 4 experiments for both drugs.
Results: At 2 hours the percent dexmedetomidine found in the fetal circulation was 12.5 (SD 5.1)%, while 48.1 (SD 20.3)% was found in the perfused placental cotyledon. A higher mean clonidine than dexmedetomidine concentration was achieved in the fetal circulation (1.90 vs. 0.56 nmol/l, P <0.05). At 2 hours the percent clonidine found in the fetal circulation was 22.1 (SD 2.4)% ( P <0.05), while 11.3 (SD 3.3)% ( P <0.05) was re tained in the perfused placental cotyledon. The transfer indexes, describing maternal-to-fetal transfer of dexmedetomidine and clonidine normalized with the transfer of antipyrine, were 0.88 (SD 0.07) and 1.04 (SD 0.08) respectively ( P <0.05).
Conclusions: Dexmedetomidine disappeared faster than clonidine from the maternal circulation, while even less dexmedetomidine was transported into the fetal circulation. This was due to its greater placental tissue retention, the basis for which probably is the higher lipophilicity of dexmedetomidine.     

Intramuscular dexmedetomidine premedication—an alternative to midazolam-fentanyl-combination in elective hysterectomy?

Sedation, anxiolysis, intubation responses and fentanyl anaesthetic requirements were investigated in a double-blind, randomized study in twenty ASA I-II elective hysterectomy patients. Ten patients received dexmedetomidine 2.5 μg kg^-1 i.m. 60 min before induction and saline placebo i.v. 2 min prior to induction (= DP group). Ten patients received midazolam 0.08 mg kg^-1 i.m. 60 min and fentanyl 1.5 μg kg^-1 i.v. (= MF group) 2 min before induction of anaesthesia with thiopentone 4 mg kg^-1. Anaesthesia was maintained with 70% nitrous oxide in oxygen and with fentanyl 2 μg kg^-1 i.v. increments according to predetermined criteria. Both premedications induced sedation ( P < 0.01 in both groups) and anxiolysis ( P < 0.01 in DP vs <0.05 in MF group) without any differences between the groups. Haemodynamic changes following tracheal intubation did not significantly differ between the groups. Intraoperatively systolic and diastolic arterial pressure were 15% and 13% lower in DP group ( P < 0.01 and P < 0.05 for drug effect), the mean heart rate was approximately 9 beats min^-1 lower in DP group (n.s.). Fentanyl was required more often in MF group: median 3.5 (QD 1.5) vs. 2.5 (QD 0.5) times in DP group ( P < 0.05), the total amount being 57% smaller in DP group: 0.03 (QD 0.01) vs. 0.07 (QD 0.02) μg kg^-1 min^-1 ( P < 0.05). Postoperative course and analgesic requirements were similar in both groups. Dexmedetomidine premedication may offer an alternative to current anaesthesia practice in elective hysterectomy.     

右美托咪定调控Nrf2/HO-1通路对H2O2诱导心肌细胞氧化应激损伤的作用研究

目的 探讨右美托咪定调控核因子E2相关因子2(Nrf2)/血红素加氧酶1(HO-1)通路对过氧化氢(H₂O₂)诱导心肌细胞氧化应激损伤的作用。方法 体外培养大鼠H9C2心肌细胞,设置对照组、H₂O₂组、1μmol右美托咪定+H₂O₂组、5μmol右美托咪定+H₂O₂组、10μmol右美托咪定+H₂O₂组。CCK-8法检测各组H9C2细胞增殖情况;酶联免疫吸附试验(ELISA)检测各组H9C2细胞丙二醛(MDA)、超氧化物歧化酶(SOD)水平;实时荧光定量聚合酶链反应(q RT-PCR)检测各组H9C2细胞Nrf2、HO-1 mRNA相对表达量;Western blotting检测各组H9C2细胞Nrf2、HO-1蛋白相对表达量。结果 与对照组比较,H₂O₂组H9C2细胞存活率、SOD水平、Nrf2、HO-1 mRNA及蛋白相对...     

Protective effects of dexmedetomidine on ischaemia-reperfusion injury in an experimental rat model of priapism

The study aimed to investigate the effects of dexmedetomidine against ischaemia-reperfusion injury occurring after priapism in a model of induced-priapism in rats. A total of 18 male rats were randomised into three groups. Group 1 was the control group. A priapism model was performed rats in Group 2 and then ischaemia-reperfusion injury was evaluated. Group 3 had similar procedures to the rats in Group 2. Rats in Group 3 additionally had 100 μg/kg dexmedetomidine administered intraperitoneally immediately after reperfusion. Blood and tissue samples were analysed. Biochemical analysis of blood samples revealed a decrease in the levels of the pro-inflammatory cytokines including interleukin-1 beta (IL-1 Beta), interleukin-6 (IL-6), and tumour necrosis factor-alpha (TNF-alpha) in Group 3 compared to Group 2 (p:.04, p:.009 and p:.009, respectively). Similarly, the highest malondialdehyde (MDA) level was in Group 2 (p:.002). The levels of antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities were significantly higher in Group 3 than that of Group 2 (p:.037 and p:.045, respectively). Direct microscopic examinations revealed positive changes in desquamation, oedema, inflammation and vasocongestion scores in Group 3 compared to Group 2 (p:.007, p:.008, p:.007 and p:.006, respectively). Dexmedetomidine has a protective effect against ischaemia-reperfusion injury in penile tissue.     

Update on ENT anaesthesia in children

This article is an update of anaesthesia for common paediatric ear, nose and throat (ENT) procedures. ENT pathology is the most common indication for surgery in children. An increasing proportion are performed as day cases, even in the presence of comorbidities such as obstructive sleep apnoea (OSA), so judicious selection of suitable children remains important. Considerations include severity of disease, known difficult airway, complex comorbidities, and the surgical centre. The anaesthetic management of frequently performed paediatric ENT procedures will be discussed, including recent advances in ENT surgery that have an impact on the anaesthetist.     

Efficacy and safety of dexmedetomidine as an adjuvant to local wound infiltration anaesthesia: A meta-analysis with trial sequential analysis of 23 randomised controlled trials

To further identify the real efficacy and safety of dexmedetomidine as an adjuvant to local wound infiltration anaesthesia, we conducted this meta-analysis. The systematic search strategy was performed using PubMed, Embase, Cochrane Library, and Chinese databases. As a result, a total of 23 RCTs (1445 patients) were included. Patients receiving dexmedetomidine combined with local anaesthetics had a lower rescue analgesia rate [risk ratio (RR): 0.48; 95% confidence interval (CI): 0.36-0.65] and lower rescue analgesic consumption [weighted mean difference (WMD): −10.80 mg; 95%CI: −13.28 to −8.31 mg] than patients receiving local anaesthetics alone. The dexmedetomidine-related adverse reactions included bradycardia (RR: 1.33; 95%CI: 0.32-5.56) and hypotension (RR: 3.00; 95%CI: 0.49-18.42). In addition, the time to first analgesic request (WMD: 296.16 minutes; 95%CI: 165.69 minutes ~ 426.63 minutes), incidence of postoperative nausea and vomiting (PONV) and pain scores at 4 hours postoperatively were also significantly lower in patients receiving dexmedetomidine combined with local anaesthetics. This meta-analysis demonstrated that the use of dexmedetomidine as an adjuvant to wound infiltration is effective for reducing the rescue analgesia rate, rescue analgesic consumption and PONV. In addition, limited evidence shows that dexmedetomidine can prolong postoperative analgesia for approximately 5 hours. Further investigations on dexmedetomidine-related adverse reactions and the dose–response effect of dexmedetomidine in wound infiltration are warranted.