间羟胺对感染性休克患者血压和肾脏功能的影响

目的观察间羟胺对感染性休克患者血压、心率和肾脏功能的影响。方法根据病情相近、病因相同、年龄相仿的原则收集1995年以来在我科ICU接受治疗的感染性休克患者70例。所有患者在休克发生后,均根据病情变化随时调整间羟胺用量,以维持血压稳定。然后根据临床使用间羟胺剂量的大小,将患者分成3组:小剂量组[A组,n=23,最大泵速为0.5～5μg/（kg.min）]、中剂量组[B组,n=23,最大泵速为6～10μg/（kg.min）]、大剂量组[C组,n=24,最大泵速为>11μg/（kg.min）]。在治疗前对患者进行APACHEIII评分,记录其血压、心率变化及尿量、BUN（血尿素氮）、CRE（肌酐）、尿ALB（白蛋白）和β2-MG（β2-微球蛋白）定量等肾功指标变化。结果抗休克治疗前,B组患者的APACHEIII评分显著高于A组,但低于C组（P<0.01）,说明3组患者的病情依次加重;所有患者BUN、CRE、尿ALB和β2-MG定量均异常升高,但组间差异无统计学意义;抗休克治疗开始后,患者尿量、BUN、CRE及尿ALB和β2-MG定量也逐步恢复（与治疗前相比,均P<0.01）,但组间各指标随时间变化差异无统计学意义。结论间羟胺用于感染性休克时,患者肾功的恢复与血流动力学的稳定相关,而与间羟胺剂量的关系不大。     

Acute changes in blood pressure as a cause of cardiac arrhythmias

The effect of an acute change in blood pressure (BP) on ventricularectopic activity and the influence of antiarrhythmic agentson this effect were examined in 24 patients. In 11 patientswith premature ventricular complexes (PVCs), the BP was temporarilyreduced by a sodium nitroprusside drip. In all of them the incidenceof PVCs was reduced (or annihilated) by the induced hypotension.In 13 patients without ventricular ectopic activity, a metaraminoldrip was given until either a PVC appeared or the systolic BPreached 200 mmHg, or symptoms appeared. In 12 cases at leastone PVC appeared and in 8 of them the total number of PVCs was13 or more, usually in the form of bigeminy. The repetitionof the test following quinidine administration (serum quinidinelevel 1.7 ±0.5 ng ml^–1) in 6 cases did not changethis pattern, with one exception. It prevented the appearanceof idioventricular accelerated rhythm in one case in whom thisrhythm had been induced by the hypertension provocative testbefore the quinidine administration. All cases, in whom thetest failed to induce more than 3 PVCs, had no cardiac problemat all. Six of the 8 cases in whom the test induced 13 or morePVCs had organic cardiac disease or palpitation. Other arrhythmiasobserved on BP elevation, were supraventricular extra beats,nodal escape rhythms and atrioventricular block. In one casewith cardiomyopathy, the BP elevation was associated with earlysigns of heart failure that subsided quickly. In conclusion, acute elevation on BP may be associated withthe generation of PVCs and its reduction with their reductionor disappearance.     

Effect of dopamine and metaraminol on the renal function of patients with septic shock

Background Vasoactive drugs are often necessary for reversing hypotension in patients with severe infection. The standard for evaluating effects of vasoactive drugs should not only be based on the increase of arterial blood pressure, but also on the blood flow perfusion of internal organs. The effects of dopamine and metaraminol on the renal function of the patients with septic shock were investigated retrospectively in this study.Methods Ninety-eight patients with septic shock were divided into three groups according to the highest infusing rate of metaraminol, with the lightest infusing rate of (0.1-0.5, 0.6-1.0, &gt;1.0) &micro;g· kg(-1)·min(-1) in group A, B and C respectively. Urine output, mean arterial blood pressure (MAP), heart rate (HR), urine output, blood urea nitrogen (BUN), creatinine (CRE), urine albumin (U-ALB), urine β(2)-microglubulin (Uβ(2)-MG)( )and Apache III scores were recorded.Results Before antishock therapy, hypotension, tachycardia and oliguria occurred to all the 98 patients with septic shock and CRE, BUN, U-ALB, Uβ(2)-MG and Apache III scoring were abnormal in most cases. With the antishock therapy, MAP, HR, urine output, BUN and CRE in all patients returned gradually to normal (P&lt;0.05 or &lt;0.01 compared to those before antishock therapy). U-ALB, Uβ(2)-MG output and Apache III scoring also reverted but remained abnormal (P&lt;0.01 compared to those before antishock therapy). No statistically significant differences in the changes of these indices with the time existed among the three groups (P&gt;0.05). Conclusion Dopamine and metaraminol when applied to the patients with septic shock could effectively maintain the circulatory stability and promote restoration of renal function.     

反相高效液相色谱法测定重酒石酸间羟胺及其注射液的有关物质和含量

 目的 采用反相高效液相色谱法测定重酒石酸间羟胺的有关物质及含量。方法 采用Phenomenex Gemini C₁₈色谱柱（4.6 mm×250 mm,5 μm）;以甲醇-0.03％己烷磺酸钠溶液（用40％磷酸调pH值至3.0）（20∶80）为流动相;有关物质检测波长为220 nm,含量测定检测波长为272 nm;柱温：35 ℃;流速1.0 mL·min^-1;进样量20 μL。结果 有关物质最低检出限为0.6 ng,含量测定定量限为7.6 ng;含量测定线性范围为12.5～75.0 μg· mL^-1,r＝0.999 9;重酒石酸间羟胺注射液的加样回收率为100.5%、100.8%和101.2%,RSD为0.5%（n=9）。结论 本法简便快捷、准确,专属性好。     

The effect of prophylactic metaraminol on systemic hypotension caused by induction of anaesthesia with propofol in patients over 55 years old

We conducted a double-blind, randomised, placebo-controlled study evaluating the efficacy of prophylactic metaraminol for preventing propofol-induced hypotension. Thirty patients aged 55-75 years undergoing general anaesthesia were randomly allocated to receive either metaraminol 0.5 mg or saline before administration of fentanyl 1 microg.kg(-1) and propofol 2 mg.kg(-1). Induction of anaesthesia was associated with a decrease in mean and systolic arterial pressure in both groups (p = 0.0001). However, there was no significant difference between the two groups. These results show that prophylactic use of metaraminol 0.5 mg does not prevent the decrease in blood pressure following fentanyl and propofol induction in older patients.     

CAIMA监控兔出血性休克的疗效评价

实验出血性休克家兔在电脑实时监测血压和自动给药系统（CAIMA）监控下，分别应用间羟胺（MET）、MET加多巴胺（DA）和MET加山莨菪碱（654－2）。结果显示：MET仅能暂时升高血压，血乳酸和肌酐值持续上升。MET加DA（5μg·kg－1·min－1）后有扩张血管降低血压作用．但增加MET用量．血乳酸和肌酐值也呈上升态势。MET加654—2（5μg·kg-1·min－1）能使血压稳定，MET用量减少，血乳酸和肌酐值下降。提示MET加654－2方案优于另2种方案。CAIMA系统在实验中能实时监测血压，自动控制MET用量，使血压较稳定地维持在预置水平；效应恒定，MET用量可不断变化，体现了治疗个体化；MET瞬时用量变化有助于正确评价MET加DA和MET加654－2两种联合用药方案的抗休克疗效。     

CAIMA对失血性休克家兔治疗反应的自动分型

开玛系统（计算机辅助即时监测给药系统）揭示的出血性休克家兔对间羟胺反应表现为３种类型：下降型，上升型和迟钝型，这在实验完成后分析记录的剂量得出的，该研究设计了实时分析系统，目的是在期间尽早地实验家兔的反应进行自动分型，计算机是每秒监测２５０次血压信号，每２．５ｓ显示所给的药量，因此才有可能根据血压和药量的变化（斜率或一一阶导数）以及二阶导数（斜率的变化），对各家兔执行自动分型，这种算法由开玛系统执     

ICU患者并联输注多种药物致静脉导管堵塞的体外药物配伍研究

目的:探讨1例ICU患者采用三通阀输液器并联输注多种静脉药物致导管堵塞的原因,为临床药师重点关注ICU患者静脉联用多种药物的安全性提供实践参考。方法:取患者同时在用的4种药物:氯化钾注射液、丙泊酚中/长链脂肪乳注射液、间羟胺注射液和地佐辛注射液,进行体外药物配伍试验,经整体混合及分别混合(丙泊酚与其他3种药物分别配伍),在电子显微镜下观察配伍后不同时间段药液的变化情况。结果:4种药液混合后,丙泊酚由最初匀质的小粒径乳滴(0.43μm)逐渐聚集增大,稳定性下降,最大乳滴粒径为3.45μm。进一步分别配伍试验证明了丙泊酚与间羟胺配伍时,乳滴蓄积与融合速度最快,4h乳滴粒径达10.36μm,已超过毛细血管平均直径;与氯化钾配伍时,乳滴蓄积与融合速度居中;与地佐辛配伍时,蓄积与融合速度最慢。结论:丙泊酚与间羟胺存在严重的配伍禁忌,应避免同时使用;与其他药物配伍时,其稳定性也会不同程度下降,建议采用双腔或多腔静脉导管单独一路输注丙泊酚中/长链脂肪乳。     

不同剂量间羟胺输注预防剖宫产腰麻后低血压的有效性

目的比较不同剂量间羟胺对剖宫产腰麻后低血压(SAIH)的预防作用。方法采用随机、双盲、对照临床试验设计,选择择期于腰麻下行剖宫产术的足月、单胎妊娠产妇90例,ASAⅠ或Ⅱ级,随机均分为3组。均采用0.4%布比卡因3 mL(12 mg)行蛛网膜下腔阻滞,推注布比卡因的同时A、B、C组开始泵注间羟胺1.0、1.5、2.0μg·kg^-1·min^-1,直至胎儿娩出后5 min。观察并记录腰麻后低血压发生率,胎儿娩出后低血压发生率,术中高血压、心动过缓、恶心、呕吐发生率,麻黄碱、阿托品用量,新生儿相关指标等。结果 A、B、C组分别完成29、29、28例。B组和C组胎儿娩出前低血压、恶心发生率和麻黄碱用量均显著低于A组(P<0.05),B组和C组之间无显著差异(P> 0.05)。C组高血压发生率显著高于A组、B组(P <0.05)。3组胎儿娩出后低血压及术中心动过缓、呕吐发生率无显著差异(P> 0.05),且均无需应用阿托品纠正心动过缓。3组新生儿Apgar评分、脐动脉血pH值等指标比较无显著差异(P> 0.05)。结论间羟胺1.5μg·kg^-1·min^-1为预防剖宫产SAIH的适宜剂量。     

Hypotension, subarachnoid block and the elderly patient

This article reviews the current literature on the management of hypotension during subarachnoid block in the elderly. Hypotension results from blockade of the sympathetic nervous system, which causes decreases in both systemic vascular resistance and cardiac output. Abolition of normal cardiovascular reflexes is also important and may explain unexpected cardiac arrests during subarachnoid block. Untreated block in the elderly results in decreases in systolic arterial pressure, systemic vascular resistance and central venous pressure. Cardiac output appears not to decrease as has been previously reported and heart rate is affected by several different factors. Preload to the heart should be maintained during block by giving adequate intravenous fluids and 8 ml. kg⁻¹ is satisfactory in most cases. Adequate preloading prevents decreases in cardiac output and unexpected cardiac arrests. In this respect, mild head down tilt is also beneficial. Ideally, intravenous fluid should be given as the block is developing. Excessive fluid administration serves no useful purpose and can cause fluid overload and urinary retention. If systolic arterial pressure decreases by more than 25%, or to below 90 mmHg, treatment with a vasopressor is indicated. The efficacy of ephedrine has recently been questioned, as it is a poor vasoconstrictor and inotrope in the elderly. The α-adrenoceptor agonists may prove a more logical choice, because they increase both peripheral resistance and preload. Metaraminol by infusion (< 10 ml.h⁻¹ of 10 mg in 20ml) has been used successfully, though hypertension can occur.