Dexmedetomidine for the treatment of postanesthesia shivering in children

BACKGROUND: Shivering is a common postanesthesia adverse event with multiple etiologies and multiple suggested prophylactic and abortive treatment regimens. Dexmedetomidine, a centrally acting alpha(2)-adrenergic agonist, has been used as a sedative agent and is known to reduce the shivering threshold. We hypothesized that children with postanesthesia shivering would reduce shivering behavior following a single bolus dose of dexmedetomidine. METHODS: Dexmedetomidine was administered in a prospective, open-label fashion. The anesthesia management was uniform consisting of maintenance inhaled anesthesia (sevoflurane) and the intraoperative administration of fentanyl (1-2 microg.kg(-1)) plus a regional anesthetic technique (either a neuraxial or peripheral block) for postoperative analgesia. Criteria for treatment included: (i) shivering, (ii) successful extubation, and (iii) no other complaint/indication of pain. All children who met the criteria were treated with a single intravenous bolus dose of dexmedetomidine (0.5 microg.kg(-1)) over 3-5 min. Following the completion of drug administration, shivering activity was recorded every minute (up to 10 min) with any adverse effects or complaints. The efficacy of shivering reduction at 5 min in this cohort is compared with previous reports from the literature of the efficacy of clonidine and meperidine. RESULTS: Twenty-four children ranging in age from 7 to 16 years (11.5 +/- 2.5 years) were treated. All children had a cessation of shivering behavior within 5 min following the completion of dexmedetomidine administration. The onset of effect was 3.5 +/- 0.9 min. No adverse effects were observed. No shivering behavior recurred. CONCLUSIONS: This study demonstrates the efficacy of dexmedetomidine in the treatment of postanesthesia shivering.     

Initial experience with dexmedetomidine for diagnostic and interventional cardiac catheterization in children

BACKGROUND: Children undergoing diagnostic and interventional cardiac catheterization require deep sedation or general anesthesia (GA). Dexmedetomidine, a selective alpha-2 adrenergic agonist, has sedative, analgesic and anxiolytic properties without respiratory depression. These characteristics make it potentially suitable as a sedative agent during diagnostic procedures in children. We report our experience using dexmedetomidine in 20 children aged 3 months to 10 years undergoing cardiac catheterization. METHODS: Following a midazolam premedication, intravenous access was secured facilitated by the inhalation of sevoflurane in oxygen. A loading dose of 1 microg x kg(-1) dexmedetomidine was administered over 10 min followed by an initial infusion rate of 1 microg x kg(-1) x h(-1). Nasal cannulae were applied, allowing endtidal CO2 monitoring with the patients breathing spontaneously. Hemodynamic parameters, Bispectral Index Score (BIS) and sedation score were measured every 5 min. Patient movement or evidence of inadequate sedation were treated with propofol (1 mg x kg(-1)). The dexmedetomidine infusion rate was titrated to the level of sedation to a maximum of 2 microg x kg(-1) x h(-1) to maintain a sedation score of 4-5 and a BIS value <80. RESULTS: Five patients (25%) had some movement on local infiltration or groin vessel access. This did not necessitate restraint or result in difficulty securing vascular access. No patients failed sedation that required the addition of another sedative agent or conversion to GA; eight patients were sedated with dexmedetomidine alone; however, 12 (60%) patients did receive a propofol bolus at some time during the procedure due to movement, increasing BIS value or in anticipation of stimulation. There were no incidences of airway obstruction or respiratory depression. In all cases the heart rate and blood pressure remained within 20% of baseline. No patient required treatment for profound bradycardia or hypotension. The average infusion rate for dexmedetomidine following the loading dose was 1.15 (+/-0.29)microg x kg(-1) x h(-1) (range 0.6-2.0 microg x kg(-1) x h(-1)). CONCLUSIONS: This initial experience showed dexmedetomidine, with or without the addition of propofol, may be a suitable alternative for sedation in spontaneously breathing patients undergoing cardiac catheterization.     

不同剂量右美托咪定对妊高征剖宫产患者血流动力学的影响

目的探讨不同剂量右美托咪定对妊高征剖宫产患者血流动力学的影响。方法将本院行择期剖宫产术的325例妊高征产妇分为对照组与A、B、C、D组,每组各65例产妇。对照组仅接受基础麻醉,A、B、C、D组在基础麻醉的基础上再分别静脉泵入0.1、0.2、0.3、0.4μg/(kg·h)试验量与维持量右美托咪定直至手术结束。分别记录所有产妇硬膜外给药前(T_0)、切皮时(T_1)、胎儿娩出时(T_2)、手术结束时(T_3)的收缩压(SBP)、舒张压(DBP)、心率(HR)等指标。结果 5组4个时间点SBP、DBP、HR相比差异均有统计学意义(P0.05);T_0时,5组的SBP、DBP、HR均显著高于本组T_1、T_2、T_3时(P0.05);T_1时的SBP、DBP、HR均显著高于本组T_2、T_3时(P0.05),其T_2时的SBP、DBP、HR均显著高于本组T_3时(P0.05)。T_0时,5组研究对象SBP、DBP、HR相比差异均无统计学意义(P0.05);T_1~T_3时,5组研究对象SBP、DBP、HR相比差异均有统计学意义(P0.05),D组的SBP、DBP、HR均显著低于A、B、C组,对照组(P0.05),C组的SBP、DBP、HR均显著低于A、B组,对照组(P0.05),B组的SBP、DBP、HR均显著低于A组、对照组(P0.05),A组与对照组之间SBP、DBP、HR相比差异均无统计学意义(P0.05)。结论在妊高征剖宫产术中,右美托咪定剂量为0.4μg/(kg·h)时具有较好的稳定血流动力学作用,且随着剂量的增加,其效果越明显。     

右美托咪定对体外循环下心内直视手术术后肺损伤的保护作用

目的探讨右美托咪定对体外循环下心内直视手术患者术后肺损伤的保护作用。方法收集我院60例心脏手术患者病例,随机分为两组,每组30例。观察组患者麻醉诱导前给予右美托咪定负荷量1.0μg/kg,维持量0.7μg/(kg·h)至手术结束,对照组不做处理。对两组患者T0(给药前)、T1(转流前)、T2(停机后1 h)、T3(停机后4 h)、T4(停机后24 h)的TNF-α、IL-1β、IL-6水平和肺泡动脉氧分压差(AaDO2)、氧合指数(OI)、呼吸指数(RI)进行对比分析。结果两组中,与T0点比较,T1~T4点TNF-α、IL-1β、IL-6呈现先增大后减小的趋势,两组各点比较差异有统计学意义(P0.05);而观察组各时间点TNF-α、IL-1β、IL-6水平显著性低于对照组(P0.05)。两组中,与T0点比较,T1~T3点AaDO2、RI均升高(P0.05),OI指数降低(P0.05);观察组各时间点AaDO2、OI、RI低于对照组(P0.05)。结论右美托咪定能有效抑制体外循环下心内直视手术患者术后炎症反应,促进修复肺损伤。     

Pediatric cardiac catheterization procedure with dexmedetomidine sedation: Radiographic airway patency assessment

Aims:

The aim of the study was to measure airway patency objectively during dexmedetomidine sedation under radiographic guidance in spontaneously breathing pediatric patients scheduled for cardiac catheterization procedures.

Subjects and Methods:

Thirty-five patients in the age group 5–10 years scheduled for cardiac catheterization procedures were enrolled. All study patients were given loading dose of dexmedetomidine at 1 μg/kg/min for 10 min and then maintenance dose of 1.5 μg/kg/h. Radiographic airway patency was assessed at the start of infusion (0 min) and after 30 min. Antero-posterior (AP) diameters were measured manually at the nasopharyngeal and retroglossal levels. Dynamic change in airway between inspiration and expiration was considered a measure of airway collapsibility. Patients were monitored for hemodynamics, recovery time and complications.

Statistical Analysis:

Student paired t-test was used for data analysis. P < 0.05 was considered significant.

Results:

Minimum and maximum AP diameters were compared at 0 and 30 min. Nasopharyngeal level showed significant reduction in the minimum (6.27 ± 1.09 vs. 4.26 ± 1.03, P < 0.0001) and maximum (6.51 ± 1.14 vs. 5.99 ± 1.03, P < 0.0001) diameters. Similarly retroglossal level showed significant reduction in the minimum (6.98 ± 1.09 vs. 5.27 ± 1.15, P < 0.0001) and maximum (7.49 ± 1.22 vs. 6.92 ± 1.12, P < 0.0003) diameters. The degree of collapsibility was greater at 30 min than baseline (P < 0.0001). There was a significant decrease in heart rate (P < 0.0001), and the average recovery time was 39.86 ± 12.22 min.

Conclusion:

Even though airway patency was maintained in all children sedated with dexmedetomidine, there were significant reductions in the upper airway dimensions measured, so all precautions to manage the airway failure should be taken.     

Mitigation of inflammation using the intravenous anesthetic dexmedetomidine in the mouse air pouch model

Dexmedetomidine, an α₂-adrenergic/imidazoline receptor agonist, is a widely used intravenous anesthetic. Its primary current usage is for sedation of patients in the intensive care unit. The mouse air pouch model is versatile in studying the anti-inflammatory effect of a drug on a local inflammation, which is induced by a variety of substances. In the present study, using the carrageenan-induced air pouch inflammation model, we tested whether dexmedetomidine mitigates inflammation occurring locally in the mouse air pouch. We found that dexmedetomidine dose-dependently inhibited the production of tumor necrosis factor (TNF)-α and interleukin (IL)-6 in the pouch and decreased the number of white blood cells (WBC) recruited into the pouch. Dexmedetomidine also dose-dependently inhibited the production of neutrophil chemokines, cxcl1 and cxcl2. Furthermore, the dexmedetomidine-induced decreased recruitment of WBC into the pouch was successfully reversed with intra-pouch administration of cxcl1/cxcl2, but not TNF-α or IL-6. Lastly, the inhibition of the production of the cytokines and chemokines with dexmedetomidine was reversed by the treatment of yohimbine, suggesting that dexmedetomidine’s anti-inflammatory effect is primarily via the stimulation of the α₂-adrenergic receptor. We conclude that dexmedetomidine has an anti-inflammatory property in the carrageenan-induced mouse air pouch inflammation model, and that the dexmedetomidine-induced inhibition of production of the neutrophil chemokines, cxcl1 and cxcl2, may be related, at least in part, to the inhibition of WBC intra-pouch recruitment.     

右美托咪定在腰-硬联合阻滞麻醉中的应用效果

目的探讨右美托咪定(DEX)在腰-硬联合阻滞麻醉(CSEA)中的临床效果。方法 244例手术患者随机分为观察组(n=122)与对照组(n=122),所有患者均在腰-硬联合阻滞麻醉下实施手术,观察组给予DEX 0.6μg/kg,对照组给予芬太尼1.5μg/kg+咪达唑仑0.03 mg/kg。比较2组患者的麻醉效果。结果 2组患者在用药10、20、30、60 min时OAA/S评分均显著低于用药前(P0.05);观察组用药后20、30、60 min的MAP、HR均显著低于对照组(P0.05);2组用药后10、20 min时Sp O2均显著降低(P0.05),且观察组显著高于对照组(P0.01)。观察组寒战发生率为10.7%,显著低于对照组36.9%(P0.01)。结论右美托咪定能发挥较好的镇静作用,且呼吸抑制作用较小,值得临床推广。     

右美托咪定对乳腺癌根治术患者Th1/Th2细胞因子的影响

[目的]观察右美托咪定对乳腺癌根治术患者Th1/Th2细胞因子的影响.[方法]择期行乳腺癌根治术患者60例,采用随机数字法,分为对照组和右美托咪定组.右美托咪定组予以右美托咪定1μg/kg负荷剂量,随后以0.5μg/kg,h静脉输注右美托咪定至术毕.对照组予以等量生理盐水.分别于给药麻醉诱导前(T0)、手术结束时(T1)、手术结束1h(T2)、手术结束24h(T3)和手术结束72h(T4)抽取外周静脉血样,采用ELISA法测定血浆IFN-γ、IL-2、IL-4和IL-10浓度,计算IFN-γ/IL-4.[结果]T0时点,对照组和右美托咪定组各指标无显著差异.与对照组相比,右美托咪定组T1、T2、T3、T4时点的IL-2、IFN-γ、IFN-γ/IL-4升高,IL-10降低,而各时点IL-4差异无统计学意义.[结论]右美托咪定可调节机体细胞免疫功能,改善Th1/Th2细胞平衡.     

右美托咪定对肿瘤化疗患者睡眠、焦虑的影响

目的:观察右美托咪定对肿瘤化疗患者睡眠、焦虑的影响。方法:利用阿森斯失眠量表（AIS）和焦虑自评量表（SAS ）,筛选自2014年3 月至6 月间患有睡眠障碍或焦虑的肿瘤化疗患者60例随机分为治疗组和对照组,治疗组于每晚入睡前持续静脉滴注1.0 μg/kg右美托咪定,30min滴完,每天1 次,连续给药3 天。对照组给予相同剂量和滴注时间的生理盐水。分别利用阿森斯失眠量表（AIS）评估患者在用药前和用药第1、2、3 天晚上的睡眠情况,利用焦虑自评量表（SAS ）评估患者在用药前和用药后第3 天的焦虑情况。结果:与对照组和用药前相比,用药第1、2、3 天晚上患者的阿森斯失眠量表（AIS）评分均明显降低（P<0.01）,用药后第3 天患者的焦虑自评量表（SAS ）也降低（P<0.01）。结论:右美托咪定可以改善肿瘤化疗患者的睡眠和焦虑症状。