右美托咪啶预防儿童七氟醚麻醉苏醒期躁动效果的观察

目的观察应用右美托咪啶预防儿童七氟醚麻醉苏醒期躁动的效果。方法将56例接受七氟醚麻醉手术的患儿随机分为2组,每组28例。观察组:麻醉诱导后静脉泵注右美托咪定注射液0.5μg/kg(稀释到15 m L),10~20 min注完后开始手术。对照组:麻醉诱导后手术开始前泵注15 m L生理盐水。比较2组患儿右美托咪啶或生理盐水注射前(T0)、注射5 min后(T1)、患儿苏醒睁眼时间点(T2)及拔管5 min后(T3)心率、血压变化和麻醉后的苏醒时间、躁动情况等。结果对照组T2和T3时点的NAP和HR较T0明显升高,差异有统计学意义(P0.05);与对照组比较,观察组T2和T3时间点MAP明显降低,同时T1、T2和T3时间点HR明显降低,差异均有统计学意义(P0.05)。观察组患儿苏醒期躁动发生率低于对照组,苏醒时间长于于对照组,2组比较差异具有统计学意义(P0.05)。结论麻醉诱导后手术开始前应用右美托咪啶,在儿童七氟醚麻醉时能较好维持血流动力学的平稳,降低苏醒期的躁动发生率。     

右美托咪啶联合舒芬太尼用于断指再植术后静脉镇痛的临床研究

目的 右美托咪啶联合舒芬太尼用于断指再植术后静脉镇痛,观察对术后疼痛、镇静效果及血管痉挛的影响.方法 60例急诊行单指断指再植患者,随机分为2组(n=30),即对照组(A组)和右美托咪啶组(B组),观察术后镇痛、镇静效果,不良反应,以及断指再植后的血管痉挛发生率.结果 术后两组患者的镇静评分、不良反应和血管痉挛发生率差异无统计学意义(P＞0.05);B组镇痛评分小于A组(P＜0.05).结论 断指再植术后应用右美托咪啶复合舒芬太尼静脉自控镇痛,右美托咪啶可以增强舒芬太尼的镇痛效果,无明显不良反应,但对血管痉挛的影响不明显.     

右美托咪定对急性主动脉夹层患者镇痛和镇静的影响:前瞻性随机对照研究

目的探讨右美托咪定(dexmedetomidine,Dex)对急性主动脉夹层(aortic dissection,AD)患者镇痛和镇静的有效性及安全性。方法选取2018年10月~2019年10入住我院ICU急性AD 50例,按随机数字表分为对照组和右美托咪定组,对照组常规吗啡、硝普钠和艾司洛尔降血压、控制心率(heart rate,HR);右美托咪定组除常规吗啡、硝普钠降压外,静脉泵入Dex 1.0μg·kg^-110 min后,持续静脉泵入Dex 0.3μg·kg^-1·h^-1维持,HR控制不良加用艾司洛尔。根据患者血压、HR调整泵药量,控制收缩压(systolic blood pressure,SBP)在120 mm Hg以下,HR 70次/min以下。在T0(入监护室即刻),T1(治疗30 min),T2(治疗2 h),T3(治疗6 h),T4(治疗24 h)5个时间点评估患者疼痛视觉模拟评分(Visual Analogue Score,VAS)及镇静评分(Ramsay评分),记录SBP、HR、动脉血氧分压(arterial oxygen pressure,PaO2)和吗啡、艾司洛尔、硝普钠用量。结果2组患者HR、SBP、PaO2和VAS评分组间、时间、组间与时间交互差异有显著性(P<0.05);Ramsay评分组间差异无显著性(P>0.05),时间、组间与时间交互有差异(P<0.05)。右美托咪定组吗啡用量明显低于对照组[(28.3±6.8)mg vs.(65.2±10.4)mg,t=13.700,P=0.000];艾司洛尔用量显著低于对照组[(775.8±126.3)mg vs.(1944.3±314.3)mg,t=17.247,P=0.000],硝普钠用量显著低于对照组[(50.1±13.5)mg vs.(101.7±16.8)mg,t=11.971,P=0.000]。结论Dex用于急性AD患者能够快速稳定血压和HR,同时产生良好的镇痛和镇静作用,减少吗啡等药物用量,起到保护作用。     

小剂量右美托咪定在无痛胃肠镜检查中的应用:前瞻性随机对照研究

目的探讨右美托咪定联合丙泊酚和舒芬太尼用于无痛胃肠镜检查的麻醉效果。方法 2016年1~3月选择ASAⅠ~Ⅱ级择期行无痛胃肠镜检查120例,随机分为2组(右美托咪定组和对照组),每组60例。右美托咪定组术前给予右美托咪定0.3μg/kg,由微量注射泵10 min泵完,泵注完成后静脉注射舒芬太尼0.1μg/kg,静脉缓慢推注丙泊酚1.5mg/kg,待病人睫毛反射消失后,手术开始。对照组术前给予等体积生理盐水,其余同右美托咪定组。2组病人术中静脉泵注丙泊酚,根据情况随时调整泵注速度,先进行胃镜检查,然后进行结肠镜检查,待结肠镜通过回盲瓣时停止丙泊酚的输入。记录术中应用丙泊酚总量,术中镇静镇痛效果,术中低血压、低血氧、体动,术后恶心呕吐、头晕、嗜睡等不良反应发生情况,术后腹痛情况,术后苏醒时间,离院时间。结果右美托咪定组丙泊酚用量明显少于对照组[(237.0±81.7)mg vs.(287.0±99.4)mg,t=3.010,P=0.003],苏醒时间[(4.5±2.1)min vs.(7.8±2.3)min,t=-8.207,P=0.000]、离院时间[(37.1±11.1)min vs.(42.2±11.3)min,t=-2.494,P=0.014]均明显短于对照组;右美托咪定组术中镇静镇痛效果优于对照组(Z=-5.266,P=0.000),术中低血氧、低血压、体动的发生率显著低于对照组[16.7%(10/60)vs.31.7%(19/60),χ~2=3.683,P=0.055;0.7%(4/60)vs.33.3%(20/60),χ~2=13.333,P=0.000;15.0%(9/60)vs.35.0%(21/60),χ~2=6.400,P=0.011],2组术后恶心呕吐、头晕等发生率无明显差异[13.3%(8/60)vs.15.0%(9/60),χ~2=0.069,P=0.793;15.0%(9/60)vs.13.3%(8/60),χ~2=0.069,P=0.793]。右美托咪定组术后腹痛评分中位数明显低于对照组[1(0,1)分vs.3(2,4)分,Z=-5.684,P=0.000]。结论小剂量0.3μg/kg右美托咪定可安全应用于无痛胃肠镜检查,能明显减少丙泊酚的用量,降低不良反应的发生,缓解术后腹痛。     

右美托咪定联合地佐辛在ICU机械通气患者中镇痛镇静的效果

目的观察右美托咪定联合地佐辛或芬太尼在ICU机械通气患者术后镇痛镇静的效果。方法选择2016年6~12月我院ICU机械通气患者57例,男35例,女22例,年龄18~75岁,将患者按随机数字表法分为三组:右美托咪定组(A组,n=17例)、右美托咪定联合芬太尼组(B组,n=20例)和右美托咪定联合地佐辛组(C组,n=20例)。比较三组患者一般状况、疼痛评分、用药前后MAP和HR、达理想镇痛镇静的时间、机械通气总时间等指标。结果三组一般资料、重症疼痛观察(CPOT)评分、治疗前后不同时点MAP和HR、机械通气时间差异无统计学意义,达到理想镇静镇痛的时间C组明显快于A组和B组(P0.05)。结论右美托咪定联合地佐辛较单用右美托咪定及右美托咪定联合芬太尼能更快达到理想镇静镇痛效果。     

右美托咪啶在腰硬联合麻醉下髋关节置换术中的应用

目的:探讨盐酸右美托咪啶在腰硬联合麻醉髋关节置换术中的镇静、镇痛效应。方法:将60例择期行髋关节置换术的患者随机分为两组,A组为盐酸右美托咪啶组(30例),A组于切皮前10min静脉泵入盐酸右美托咪啶1μg/kg,持续10min后改为静脉泵入盐酸右美托咪啶0.4μg/kg,维持至手术结束前30min;B组为对照组(30例),观察并记录两组麻醉前(T0)、腰硬联合麻醉后10min(T1)、切皮后30min(T2)、切皮后60min(T3)、术毕(T4)各时点MAP、HR及Narcotrend指数(NT1)的变化,使用Ramesay法进行镇静评分。结果:A组术中HR、MAP较平稳,B组在T2时点后HR、MAP明显升高(P<0.05);A组NT1值在T2时点后呈进行性的下降(P<0.05);Ramesay评分A组在T2时点后进行性增加(P<0.05)。结论:右美托咪啶在腰硬联合麻醉髋关节置换术中具有良好的镇痛、镇静效应。     

右美托咪定复合氟比洛芬酯预防全麻苏醒期躁动的临床研究

目的观察右美托咪定复合氟比洛芬酯对全麻患者苏醒期躁动及拔管期心血管反应的影响。方法择期行全身麻醉的口腔颌面部肿瘤手术患者80例,ASAⅠ或Ⅱ级,随机分为氟比洛芬酯组(F组)、右美托咪定组(D组)、右美托咪定复合氟比洛芬酯组(DF组)和对照组(C组),每组20例。F组于手术结束前30min经静脉注射氟比洛芬酯50mg;D组于手术结束前30min经静脉注射右美托咪定0.5μg/kg;DF组手术结束前30min经静脉注射氟比洛芬酯50mg,同时经静脉注射右美托咪定0.25μg/kg;C组静脉注射与D组等容量的生理盐水。记录四组患者拔管前(T0)、拔管时(T1)、拔管后5min(T2)MAP、HR的变化;记录苏醒时间、拔管时间以及拔管前Riker镇静躁动评分、拔管后5min的Ramsay镇静评分。结果 T1、T2时F组、C组MAP明显高于,HR明显快于T0时(P0.05或P0.01);D组、DF组MAP明显低于,HR明显慢于C组(P0.01)。D组苏醒时间、拔管时间明显长于,Ramsay镇静评分明显高于其他三组(P0.05);D组、DF组Riker镇静躁动评分明显低于C组(P0.05);D组、DF组患者躁动发生率明显低于C组(P0.05或P0.01)。结论右美托咪定0.25μg/kg复合氟比洛芬酯50mg可有效降低全麻患者苏醒期躁动并能降低患者拔管期心血管反应,不会延长患者的苏醒时间和拔管时间。     

右美托咪定复合地佐辛防治老年高血压肺癌全麻苏醒期躁动

目的:探讨右美托咪啶联复地佐辛在老年高血压患者肺癌根治手术的麻醉效果及应用价值。方法:选择行肺癌根治手术的老年高血压患者150例,采用随机数字表法分为3组,A组给予生理盐水作为对照组,B组给予右美托咪啶,C组给予右美托咪啶复合地佐辛,比较3组全麻苏醒期躁动发生情况及安全性。结果:C组Ramsay评分3.17±0.72分,躁动发生率4.00%,疼痛VAS评分(1.34±0.56)分,显著优于A、B两组,组间对比差异有统计学意义(P0.05)。C组T1期HR(86.54±4.71)次/min,MAP(93.54±7.81)mm Hg(1 mm Hg=0.133 k Pa),T2期HR(84.76±4.58)次/min,MAP(93.16±7.72)mm Hg,均显著优于同时间节点A、B组,间对比差异有统计学意义(P0.05)。结论:右美托咪啶联复合地佐辛应用于老年高血压肺癌根治手术能够明显降低全麻苏醒期躁动程度,稳定血流动力学指标,安全可靠。     

右美托咪啶在腰硬联合麻醉患者术中的镇静效果分析

目的探讨右美托咪啶在腰-硬联合麻醉(CSEA)术中的镇静效果。方法将120例拟行CSEA的手术患者采用数字表法随机分为对照组和观察组,每组各60例,分别给予等容量生理盐水和右美托咪啶。观察并比较2组镇静效果及手术遗忘情况。结果观察组T2、T3、T4时Ramsay评分均较T0时和对照组各时间点均明显提高,差异有统计学意义(P0.05)。观察组遗忘率(61.67%)显著高于对照组(0.00),差异有统计学意义(P0.05)。结论右美托咪啶用于CSEA术中镇静效果显著,患者术后遗忘率高,效果满意。     

硬膜外注射右美托咪定、芬太尼用于下肢手术镇痛的效果评价

目的 观察和评价硬膜外注射右美托咪定、芬太尼复合罗哌卡因用于下肢手术的镇痛效果.方法 美国麻醉医师协会(ASA)分级Ⅰ～Ⅱ级患者100例,按随机数字表法分为两组(每组50例):罗哌卡因+右美托咪定组(RD组)和罗哌卡因+芬太尼组(RF组).除记录循环、呼吸指标及镇静评级外,于硬膜外给药后即刻观察T1o痛觉消失时间、最高感觉阻滞平面、完全运动阻滞时间、感觉阻滞消退两个节段的时间、首次追加镇痛药物的时间及副作用的发生情况等.结果 两组患者一般情况差异无统计学意义(P＞0.05).RD组T10痛觉消失和完全运动阻滞时间[(7.1±1.2)min和(18.0±3.6) min]明显早于RF组[(9.2±1.8) min和(22.0±3.0) min](P＜0.05),RD组术后镇痛时间[(361±20) min]长于RF组[(259±32) min],且硬膜外局麻药总用量[(76±10)mg]显著少于后者[(97±l4)mg](P＜0.01);镇静效果评级RD组(76％)显著好于RF组(18％)(P＜0.01).RF组恶心、呕吐的发生率(28％和14％)较RD组(16％和6％)明显升高(P＜0.05),而RD组口干的发生率(16％)显著高于RF组(4％)(P＜0.01).结论 硬膜外注射右美托咪定用于下肢手术镇痛,可提供较为稳定的血流动力学,感觉神经阻滞起效快,术后镇痛时间延长,药物用量少,镇静效果良好.     

Histochemical and contractile properties of striated muscles of urethra and levator ani of dogs and sheep

AIMS: To understand their possible importance in long- and short-term control of continence, some properties of the striated muscles of the urethra and pelvic floor (levator ani) of dogs and sheep were investigated, especially fiber types and contractile characteristics. MATERIALS AND METHODS: Striated muscles of urethra and levator ani of 29 male and 6 female dogs and 11 male and 6 female sheep were removed and cut into strips. Some strips were frozen and stained for ATPase at pH 9.4 and 4.3 for fiber typing; others were set up in an organ bath to study contractile responses to nerve stimulation. RESULTS: All muscles contained both type I (slow) and type II fibers, ranging from 97% type II in female greyhound urethra to 60% in female sheep levator ani. For each muscle, there were fewer type II muscles in sheep than in dog. The diameters of the urethral fibers were about 60% of the levator ani in dogs and 34% in sheep. Contraction of the urethral muscle was faster than for levator ani and declined to about 80% of the peak, 500 msec after the beginning of stimulation at 20 Hz. The levator ani contraction rose to a steady level as long as stimulation continued. CONCLUSIONS: Both the levator ani and urethral striated muscles contain slow and fast fiber types. The levator ani muscles are capable of sustained contraction with rapid onset which will produce long-term closure of the urethra. The circular urethral muscle contraction was faster but less well maintained.     

Recognition and management of phaeochromocytoma and paraganglioma

Phaeochromocytomas and paragangliomas (PPGL) are catecholamine-secreting neuroendocrine tumours arising from the chromaffin cells in the adrenal medulla. These tumours may be identified incidentally, as part of a work-up for multiple endocrine neoplasia or following haemodynamic surges during unrelated procedures. Advances in perioperative management and improved management of intraoperative haemodynamic instability have significantly reduced surgical mortality from around 40% to less than 3%. Surgery is the definitive treatment in most cases and laparoscopic resection where possible is associated with improved outcomes. Anaesthetic management of PPGL cases represents a unique haemodynamic challenge both before and after tumour resection. In this article we describe the physiology of these tumours, their diagnosis, preoperative optimization methods, intraoperative anaesthetic management and management of postoperative complications.     

Instrumented ligamentotaxis and stabilization of compression and burst fractures of dorsolumbar and mid-lumbar spines

Background:

Controversy continues regarding the best treatment for compression and burst fractures. The axial distraction reduction utilizing the technique employing the long straight rod or curved short rod without derotation to reduce fracture are practised together with short segment posterolateral fusion (PLF). Effects of the early postoperative mobilization without posterolateral fusion on reduction maintenance and fracture consolidation were not evaluated so far. The present prospective study is designed to assess the effectiveness of i) reduction and restoration of sagittal alignment, ii) no posterolateral fusion on the reduced, fractured vertebral body and injured disc, iii) fracture consolidation and iv) the fate of the unfused cephalad and caudal injured motion segments of the fractured vertebra.

Materials and Methods:

The study includes 15 Denis burst and two Denis type D compression fractures between T₁₂ and L₃. The lordotic distraction technique was used for ligamentotaxis utilizing the contoured short rods and pedicle screw fixator. Three vertebrae including the fractured one were fixed. The patients after surgery were braced for ten weeks with activity restriction for 2-4 weeks. The patients were evaluated for change in vertebral body height, sagittal curve, reduction of retropulsion, improvement in neural deficit. The unfused motion segments, residual postoperative pain and bone and metal failure were also evaluated.

Results:

The preoperative and postreduction percentile vertebral heights at, zero (immediate postoperative), at three, six and 12 months followup were 62.4, 94.8, 94.6, 94.5 and 94.5%, respectively. The percentages of the intracanal fragment retropulsion at preoperative, and postoperative at zero, 3, 6 and 12 months followup were 59.0, 36.2,, 36.0, 32.3, and 13.6% respectively.The preoperative and postreduction percentile loss of the canal dimension and at zero, three, six and 12 months were 52.1, 45.0, 44.0, 41.0 and 29% respectively suggesting that the under-reduced fragment was being resorbed gradually by a remodeling process. The mean initial kyphosis of 33° became mean 2° immediately after reduction and mean 3° at the final followup. The fractured vertebral bodies consolidated in an average period of ten weeks (range 8-14 weeks). The restored disc heights were relatively well maintained throughout the observation period. All paraparetic patients recovered neurologically. There were no postoperative complications.

Conclusion:

Instrument-aided ligamentotaxis for compression and burst fractures utilizing the short contoured rod derotation technique and the instrumented stabilization of the fractured spine are found to be effective procedures which contribute to the fractured vertebral body consolidation without recollapse and maintain the motion segment function.     

Incorporation and release of85Sr and14C-proline-hydroxyproline in mineral and collagen of bone and incisor teeth of growing rats

The extent to which exchange and reutilization processes of mineral tracers affect skeletal mineral accretion and resorption measurements was evaluated by comparing the rates of appearance and disappearance of⁸⁵Sr and¹⁴C-proline-hydroxyproline in bones and teeth in growing rats for 12 days following simultaneous parenteral injection of these tracers. Expressions for the relative rates of collagen synthesis and breakdown, which unlike mineral metabolism are considered not to be complicated by exchange phenomena, were based on¹⁴C-proline conversion to¹⁴C-hydroxyproline; the specific activity of the latter was determined. Both the mineral and the collagen specific activities reflected the rates and patterns of growth of the samples assayed; rapid growth and a short interval of time between formation and resorption of tissue in themetaphyseal bone which contains the cartilagineous growth plate, slow growth and an interval of time between formation and resorption of tissue indiaphyseal bone and incisor teeth which is longer than the 12 days of the experiment. However, in metaphyseal bone the specific activity collagen/mineral ratio dropped by one half during the 4–12 day interval in contrast to diaphyseal bone and incisor teeth in which no change in this ratio was observed during this period of time. The data indicate that collagen in the metaphyseal growth zone is removed by resorption before it has become fully mineralized, and that exchange is a relatively unimportant factor in the long term kinetics of bone mineral.

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Zusammenfassung Das Ausmaß, bis zu welchem Austausch- und Wiederverwendungsprozesse der mineralen Tracer die Messungen des mineralen Skelett-Auf- und Abbaues beeinflussen können, wurde ausgewertet; zu diesem Zweck wurde die Geschwindigkeit des Auftretens und Verschwindens von⁸⁵Sr und von¹⁴C-Prolin-Hydroxyprolin in Knochen und Zähnen von wachsenden Ratten während der 12 auf die simultane parenterale Injektion dieser Tracer folgenden Tage verglichen.Der Ausdruck für die relative Geschwindigkeit des Kollagen-Auf- und Abbaues, bei welchem im Gegensatz zum Mineralmetabolismus kein Mitwirken des Austauschphänomens vermutet wird, basiert auf der Umwandlung von¹⁴C-Prolin zu¹⁴C-Hydroxyprolin; die spezifische Aktivität des letzteren wurde bestimmt.Aus der spezifischen Aktivität des Minerals sowie jener des Kollagens konnten die Geschwindigkeit und die Art des Wachstums der untersuchten Proben ersehen werden, d.h.schnelles Wachstum und ein kurzes Zeitintervall zwischen Bildung und Resorption des Gewebes imKnochen der Metaphyse, die auch die knorpelige Wachstumsplatte enthält, und andererseitslangsames Wachstum und längeres Zeitintervall (länger als die 12 Tage des Experimentes) zwischen Bildung und Resorption des Gewebes imKnochen der Diaphyse und in den Schneidezähnen. Immerhin fiel die spezifische Aktivität des Kollagen/Mineral-Anteils im Knochen der Metaphyse während dem 4–12tägigen Zeitintervall auf die Hälfte, im Gegensatz zum Knochen der Diaphyse und der Schneidezähne, bei welchen während dieser Zeitspanne kein Unterschied in diesem Verhältnis beobachtet wurde.Diese Ergebnisse zeigen, daß Kollagen in der Wachstumszone der Metaphyse durch Resorption verschwindet, bevor es ganz mineralisiert ist, und daß der Austausch ein relativ unwichtiger Faktor in der Kinetik auf lange Sicht des Knochenminerals ist.

     

Physiology and pharmacology of nausea and vomiting

Nausea and vomiting are both very unpleasant experiences. The physiology is poorly understood; however, understanding what we do know is key to tailoring a preventative or therapeutic antiemetic regime. There are two key sites in the central nervous system implicated in the organization of the vomiting reflex: the vomiting centre and the chemoreceptor trigger zone. There are five key neurotransmitters involved in afferent feedback to these areas. These are histamine (H₁ receptors), dopamine (D₂), serotonin (5-HT₃), acetyl choline (muscarinic) and neurokinin (substance P). Postoperative nausea and vomiting will occur in around one-third of elective patients who have no prophylaxis. This can result in many detrimental effects including patient dissatisfaction, unplanned admission and prolonged recovery. It is therefore essential that clinicians understand how they can prevent and treat nausea and vomiting using either a single agent or a combination of antiemetics to target relevant receptors. Commonly used drugs include antihistamines, dopamine antagonists, serotonin antagonists and steroids. More novel agents are being developed such as aprepitant, a neurokinin receptor antagonist, palonosetron, a 5HT₃ receptor antagonist and nabilone, a synthetic cannabinoid.     

Physiology and pharmacology of nausea and vomiting

Nausea and vomiting are both very unpleasant experiences. The physiology is poorly understood; however, understanding what we do know is key to tailoring a preventative or therapeutic antiemetic regime. There are two key sites in the central nervous system implicated in the organization of the vomiting reflex: the vomiting centre and the chemoreceptor trigger zone. There are five key neurotransmitters involved in afferent feedback to these areas. These are histamine (H₁ receptors), dopamine (D₂), serotonin (5-HT₃), acetyl choline (muscarinic) and neurokinin (substance P). Postoperative nausea and vomiting will occur in around one-third of elective patients who have no prophylaxis. This can result in many detrimental effects including patient dissatisfaction, unplanned admission and prolonged recovery. It is therefore essential that clinicians understand how they can prevent and treat nausea and vomiting using either a single agent or a combination of antiemetics to target relevant receptors. Commonly used drugs include antihistamines, dopamine antagonists, serotonin antagonists and steroids. More novel agents are being developed such as aprepitant, a neurokinin receptor antagonist, palonosetron, a 5HT₃ receptor antagonist, and nabilone, a synthetic cannabinoid.     

动静脉穿刺网络课件的开发及其应用

目的:确保护理教学效果,提高教学水平。方法:应用多项信息技术将动静脉穿刺技术制作成教学网络课件,并用于临床教学。结果:该课件在本校园网上运行半年余,2000余人次对其进行访问,受到师生好评。结论:该课件能及时反映动静脉穿刺的最新研究进展及具体操作步骤和使用方法,实现护理教学的直观性和交互性,对护理教学和临床带教指导有一定的借鉴作用。     

Physiology and pharmacology of nausea and vomiting

The physiology of nausea and vomiting is poorly understood. The initiation of vomiting varies and may be due to motion, pregnancy, chemotherapy, gastric irritation or postoperative causes. Once initiated, vomiting occurs in two stages, retching and expulsion. The muscles responsible for this sequence of events are controlled by either a vomiting centre or a central pattern generator, probably in the area postrema and the nearby nucleus tractus solitarius. Drugs which induce vomiting include ipecacuanha, a gastric irritant, and apomorphine, a dopamine-receptor agonist. Opioid drugs also induce vomiting, but opioid antagonists are not useful to treat nausea and vomiting. Anti-emetic drugs consist of a variety of neurotransmitter antagonists and may act in the periphery, the central nervous system or both sites. The most important drugs are antagonists at muscarinic, dopamine D₂, 5-HT₃, histamine H₁ and neurokinin NK₁ receptors. These drugs are discussed with particular attention to post-operative nausea and vomiting (PONV).