应用FRAX骨折风险预测工具模拟评估不同国家人群骨折风险的临床研究

目的应用FRAX工具模拟评估中国、日本、德国三国人群的10年内重要部位骨折概率(PMOF)及10年内髋部骨折概率(PHF),分析比较不同国家的骨折风险性差异,分析比较各国骨折风险与年龄、性别的变化关系。方法收集2976例受检者FRAX骨折风险评估危险因素11项及股骨颈骨密度BMD,应用FRAX骨折风险评估网站分别模拟评估中国、日本、德国三国模式下PMOF、PHF,采用两独立样本t检验及Mann-Whitney U检验分别对三国数据进行两两比较,并观察三国PMOF、PHF性别间差异及随年龄的变化趋势。结果 1)三国不论男性、女性,均表现为PMOF在40～49岁中国最小、德国最大,50岁以上中国最小、日本最大,且差异有统计学意义。PHF在40岁～59岁日本最小、德国最大,60岁以上中国最小、德国最大,且差异有统计学意义。(2)三国不论男性、女性,PMOF、PHF均随年龄的增长而增长,仅中国在80岁以上年龄组两者概率有所下降。三国50岁以后女性10年内骨质疏松性骨折概率均大于男性,且女性PMOF、PHF概率增长的速度明显大于男性。结论骨质疏松性骨折的发生概率存在地域差异,在同等条件下,欧洲国家发生骨质疏松性骨折的概率大于亚洲国家,发达国家骨折的概率大于发展中国家。骨质疏松性骨折的发生概率随年龄增长而增长,女性较男性更易发生骨质疏松性骨折。     

FRAX评估江苏镇江地区中老年人群骨折风险的回顾性研究

目的评估FRAX■工具对江苏镇江地区中老年人骨质疏松性骨折的预测价值。方法对1070例江苏镇江地区中老年人群进行分组性研究,应用FRAX■工具计算未来10年主要骨质疏松性骨折(probability of major osteoporosis fracture,PMOF)和髋部骨折的概率(probability of hip fracture,PHF),分析年龄、体质量指数、有无骨质疏松性骨折史以及不同骨量对FRAX预测结果的影响。结果随着年龄的增长10年内PMOF和PHF同步增加;随着体重指数的增加,10年内PMOF和PHF同步下降;有骨质疏松性骨折史的人群10年内PMOF和PHF明显增加;随着骨量下降,10年内PMOF和PHF逐渐增加;不同骨量受人群在不同骨质疏松骨折风险组中的分布不同。在骨质疏松性骨折高风险人群中,骨质疏松者占78.1%,低骨量者占20.7%,正常骨量者占1.3%。结论FRAX■工具可用于江苏镇江地区中老年人群骨质疏松骨折风险的评估。FRAX■工具可能低估了低骨量人群的骨质疏松性骨折的风险,该工具对中老年低骨量人群的预测价值值得进一步研究。     

FRAX在青海地区不同民族2型糖尿病患者骨折风险评估的临床应用

目的探讨骨折风险评估工具(FRAX)对青海地区汉族、回族、藏族2型糖尿病(diabetes mellitus type 2,T2DM)患者骨折风险评估的临床应用价值。方法随机选择2018年12月至2020年10月青海大学附属医院收治的符合纳入与排除标准的研究对象324例,收集所选患者的FRAX中相关骨折危险因素,在FRAX中录入相关指标后计算3组患者未来10年髋部骨折概率(PHF)及主要部位骨折概率(PMOF);根据民族将其分为汉、回、藏3组,比较三民族PMOF及PHF的差异;根据代入与不代入股骨颈骨密度T值分为FRAX(BMD-T)组和FRAX组,比较代入和不代入BMD-T时各民族PMOF及PHF的差异;以股骨颈骨密度T值≤-2.5为干预治疗金标准,运用ROC曲线确定本地区最佳干预阈值。结果①三民族代入和不代入BMD-T时PMOF和PHF差异均有统计学意义(P<0.05)。②三民族PHF在男性人群中差异有统计学意义(P<0.05),女性无差异(P>0.05);而三民族PMOF在男性、女性人群中差异均无统计学意义(P<0.05)。③FRAX预测未来10年PMOF的ROC曲线下面积为0.986(P<0.001),cutoff值为3.80%,PHF的ROC曲线下面积为0.993(P<0.001),cutoff值为2.00%。结论①FRAX中代入BMD-T能更准确评估本地区T2DM患者骨折风险并指导治疗,当PMOF≥3.8%或PHF≥高于2.0%时即需要干预治疗。②三民族男性患者中汉族PHF最高,回族、藏族无差异,PMOF三民族间无差异;女性患者中PHF、PMOF三民族间无差异。     

应用FRAX工具评价莆田地区中老年骨质疏松骨折风险的临床研究

目的通过应用骨折风险评估工具(FRAX)及检测股骨颈骨密度(BMD)方法对本院3881例中老年人进行研究,探讨FRAX工具与由检测股骨颈骨密度分析其未来10年内发生主要骨折风险概率(PMOF)及10年内髋骨骨折概率(PHF)的关系。方法选取2017年1月至12月在莆田市第一医院门诊、病房以及体检的人员进行回顾性分析,均接受双能X线骨密度仪(美国Hologic,Discover A)检测股骨颈BMD的3881例检查人员作为研究对象,其中男性1218例,女性2663例,平均年龄(61. 5±12. 6)岁,按每十岁为一个年龄段,分别为40～49岁、50～59岁、60～69岁、70～79岁和≥80岁5个组,采用"中国"模式FRAX软件分析,系统自动生成PMOF及PHF,BMD用T值表示,T-1. 0为BMD异常(骨量低下和骨质疏松),T≥-1为BMD正常组。应用SPSS 25. 0软件进行数据分析,P0. 05为差异有统计学意义。结果 3881例参与者中BMD异常组1954例(51%),BMD正常组1927例(49%)。BMD异常组与正常组比较,年龄较高、体重较轻、身高变矮较多及体质量指数(BMI)较低(P0. 001),应用FRAX工具在有或无录入骨密度值的情况下,BMD异常组PMOF及PHF(%)均显著高于正常组(P0. 001); FRAX与骨密度测定值的相关分析得出FRAX预测的PMOF与股骨颈骨密度T值之间呈显著负相关,不同年龄段中,40～49、50～59、60～69、70～79岁组及≥80岁的BMD异常发生率分别为28. 9%,40. 1%,53. 9%,68. 2%,76. 2%,平均为50. 3%。随着年龄的增大,PMOF显著升高,组间差异具有统计学意义(P0. 001)。有或无录入BMD值的情况下,骨密度异常组在不同年龄段PMOF及PHF(%)也均显著高于正常组(P0. 001)。结论在有或无录入股骨颈骨密度值情况下应用FRAX评估工具得出,所有参与者的未来10年内发生主要骨折风险的概率均随年龄增大而增高,因此建议把FRAX作为一项骨质疏松基本的筛查工具在我国缺乏骨密度测定仪时推广应用,但骨质疏松骨折的发生概率较国外低,有待进一步研究。     

系统应用糖皮质激素患者的FRAX骨折风险评估分析

目的 通过使用糖皮质激素（glucocorticoid,GC）校正的骨折危险性评估工具（fracture risk assessment tool,FRAX）,评估系统应用GC对风湿病患者群体骨折风险的影响。方法 纳入2019年1月至2020年1月于解放军总医院第四医学中心就诊且行髋部和腰椎骨密度检测的风湿病患者180例和同期健康体检者180名,风湿病患者均系统性使用GC治疗超过3个月,按照日均GC剂量（等同于醋酸泼尼松）分为GC≤7.5 mg组,7.5 mg＜GC＜30 mg组和≥30 mg组,并对剂量超过7.5 mg的两组进行骨折风险校正,使用FRAX评估系统评估未来10年主要骨质疏松性骨折（PMOF）和髋部骨折（PHF）发生概率,并比较组间的差异。结果 ①激素使用组PMOF和PHF高于健康对照组,且差异有统计学意义（P＜0.05）;②按GC使用时间分为＞2年组和≤2年组,GC使用＞2年组PMOF和PHF均高于≤2年组,且差异有统计学意义;③FRAX校正前GC≤7.5 mg组的PMOF与PHF高于另外两组,差异有统计学意义;④FRAX校正后GC≤7.5 mg组PMOF与PHF仍高于另外两组,与GC≥30 mg组相比差异有统计学意义;⑤按骨质疏松治疗阈值PMOF 20 %、PHF 3 %计算,激素使用组达到PMOF和PHF治疗阈值者分别为0例和9例（5 %）;按2017年GIOP推荐的骨质疏松治疗阈值PMOF 10 %、PHF 1 %计算,达治疗阈值者分别为8例（4.44 %）和41例（22.78 %）。结论 经GC校正后可提高基于FRAX计算出的风湿病患者的骨折风险,且校正后增加了达到骨质疏松治疗阈值的人数,能更有效的预测使用GC的风湿病群体骨折概率,尽早实施预防骨质疏松,从而降低骨折概率。     

应用FRAX评价乳腺癌术后患者骨折风险的临床研究

目的应用骨折风险评估工具(fracture risk assessment tool,FRAX)评价乳腺癌术后患者骨折风险的临床研究。方法选取2017年3月至2019年8月在连云港市第一人民医院接受过手术治疗的Ⅰ期至Ⅲ期乳腺癌女性181例作为观察组,并选取181例年龄和身体质量指数匹配的非乳腺癌女性作为对照组,收集个人基本信息、骨折风险因素、股骨颈骨密度(bone mineral density,BMD)及治疗方式等资料,比较不同组间的骨折风险,并进行骨折风险与临床因素的回归分析。结果(1)乳腺癌术后患者10年内主要部位骨质疏松性骨折概率(probability of major osteoporotic fracture,PMOF)和10年内髋部骨折概率(probability of hip fracture,PHF)较对照组无显著增加(P=0.570、0.582);(2)PMOF在芳香化酶抑制剂组最高,他莫昔芬组最低(P<0.05)。芳香化酶抑制剂组的PHF显著高于单纯化疗组和他莫昔芬组(P<0.05);(3)回归分析显示,年龄、股骨颈BMD、骨折史、父母髋部骨折史和激素应用史对PMOF的影响具有统计学意义(P<0.05)。年龄、股骨颈BMD、骨折史对PHF的影响具有统计学意义(P<0.05)。结论应用FRAX工具评估乳腺癌术后患者的骨折风险尚需进一步研究。     

桂西地区骨质疏松患者FRAX评分与体质量指数及外周血中钙、磷指标的相关性分析

目的探讨桂西地区骨质疏松患者FRAX评分与体质量指数及外周血中钙、磷指标的相关性。方法随机选取右江民族医学院附属医院2015年1~6月住院患者221例,根据纳入标准筛选出69例。诊断为骨质疏松患者33例,男12例,女21例;诊断为非骨质疏松患者36例,男18例,女18例。随访并计算FRAX评分、收集相关临床电解质指标后采用独立样本t检验分别统计分析骨质疏松组和非疏松组整体人群相关患者钙、磷离子值。多重线性回归分析未来10年骨折风险概率/体质量指数(PMOF/BMI)、10年内髋部骨折概率/体质量指数(PHF/BMI)之间的关系。研究桂西地区患者FRAX评分及BMI与外周血中钙、磷指标是否存在相应关系。结果在骨质疏松组患者和整体人群中,外周血钙、磷及年龄等因素与PMOF和PHF之间均没有相关性(各项P值均>0.05)。在骨质疏松组中,BMI与PMOF和PHF之间没有相关性(P值均>0.05)。但是在整体人群中,BMI与PMOF和PHF之间有线性相关性(P<0.05),并且随着BMI增加,PMOF和PHF的数值越来越小。结论骨质疏松患者外周血钙、磷指标与骨质疏松骨折风险无明显相关性。依据本试验统计学分析,钙、磷指标在本算法中不能作为桂西地区诊断骨质疏松骨折风险的依据;在整体人群中,BMI与PMOF和PHF之间呈现负向相关性,提示低BMI人群容易发生骨折。     

在中老年人群中2型糖尿病病程和FRAX评分之间相关性分析

目的探讨FRAX评分在与糖尿病病程之间的关系。方法选取278例糖尿病人群,并收集相关临床指标。通过FRAX公式计算2型糖尿病患者10年髋部骨折发生概率(PHF)和10年主要骨质疏松性骨折发生概率(PMOF)。研究2型糖尿病患者中FRAX与糖尿病病程之间的关系。结果发现随着糖尿病病程的延长,L_(1-4)、股骨颈骨密度均无明显改变(P0.05),而随着病程的增长,PMOF、PHF水平之间有区别,差异有统计学意义,且随着病程的延长两者呈逐渐增大的趋势(P0.05)。结论糖尿病病程与10年骨质疏松性骨折发生概率之间有密切相关性。     

FRAX®探讨绝经后骨质疏松症中医证型与骨折风险的相关性研究

目的 运用FRAX? ( fracture risk assessment tool，FRAX? )评估不同证型骨质疏松症( osteoporosis，OP)患者骨折风险，从中医辨证角度探讨骨折高风险人群的临床特征，以期更好地预防骨折发生。方法 选取2021年12月至 2022年3月在南京中医药大学附属无锡中医医院骨伤科门诊纳入的绝经后骨质疏松症女性 125 例。依照中医辨证分型将患者分为脾肾阳虚、肝肾阴虚、肾阳虚以及血瘀气滞4组，采集所有受试者临床资料，运用FRAX?计算各组患者发生髋部骨折的发生概率( probability of hip fractures，PHF) 以及主要骨质疏松性骨折概率( probability of major osteoporotic fractures，PMOF)，分析骨质疏松症中医证型与骨折风险的相关性。结果 与肝肾阴虚、肾阳虚以及血瘀气滞组相比，脾肾阳虚组BMI指数最低，差异具有统计学意义（P=0.020、P＜0.001、P=0.040）；与肝肾阴虚、肾阳虚以及血瘀气滞组相比，脾肾阳虚组骨密度T值最低，差异具有统计学意义（P=0.002、P＜0.001、P=0.040）；4组骨折率差异具有统计学意义（χ2=11.23，P=0.010），脾肾阳虚组骨折率高于肝肾阴虚组，差异具有统计学意义（P=0.001）；不代入骨密度T值各组PHF、PMOF差异无统计学意义（H=4.853，P=0.183；H=4.691，P=0.196）；代入骨密度计算各组PHF，脾肾阳虚组PHF高于肝肾阴虚、肾阳虚组PHF，差异具有统计学意义（P=0.017、P＜0.001）；脾肾阳虚组PMOF高于肝肾阴虚、肾阳虚组PMOF，差异有统计学意义（P=0.025、P=0.001）。结论 脾肾阳虚证OP患者骨折风险更高，将现代医学骨折风险评估工具FRAX与传统中医辨证内容相结合，有望OP患者能更早了解自身骨折风险从而更好地预防骨折发生。     

FRAX评估北京地区中老年人群骨折风险的回顾性研究

目的评价WHO发布的骨折风险评估工具FRAX对北京地区中老年人群的适用性,预测北京地区不同性别及年龄亚组中老年人群的骨折风险,讨论既往骨折病史对于FRAX的影响。方法对3021例北京地区中老年人群进行分组性研究。输入相关资料及FRAX工具中所包含的危险因素,计算未来10年内发生全身骨质疏松性骨折及髋部骨折的风险概率,比较既往骨折病史人群对FRAX预测结果影响。结果北京地区女性中老年人群未来10年内骨折风险远高于同年龄组男性;伴随年龄增大,未来10年内发生全身骨质疏松性骨折及髋部骨折的风险概率不分性别均同步增高。有既往骨折病史的老年人群10年内再发骨折风险远高于无骨折史人群。结论利用FRAX工具可以对北京地区中老年人群骨折风险做出有效评估,针对于不同性别、不同年龄亚组的人群,联合髋部BMD值后获取的FRAX预测在既往骨折或未骨折患者中均具有临床应用价值。FRAX评估工具在骨质疏松的诊断、治疗及预后评价等方面具有良好的临床应用价值。     

Vasopressor hormone response following mesenteric traction during major abdominal surgery

Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI₂) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI₂), TXB₂ (stabile metabolite of thromboxane A₂) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI₂ release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF_1α (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB² (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI₂ release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A₂, presumably contributing to hemodynamic stability within 30 min after MT.     

A Teaspoon Pump for Pumping Blood with High Hydraulic Efficiency and Low Hemolysis Potential

Abstract: Virtually all blood pumps contain some kind of rubbing, sliding, closely moving machinery surfaces that are exposed to the blood being pumped. These valves, internal bearings, magnetic bearing position sensors, and shaft seals cause most of the problems with blood pumps. The original teaspoon pump design prevented the rubbing, sliding machinery surfaces from contacting the blood. However, the hydraulic efficiency was low because the blood was able to "slip around" the rotating impeller so that the blood itself never rotated fast enough to develop adequate pressure. An improved teaspoon blood pump has been designed and tested and has shown acceptable hydraulic performance and low hemolysis potential. The new pump uses a nonrotating "swinging" hose as the pump impeller. The fluid enters the pump through the center of the swinging hose; therefore, there can be no fluid slip between the revolving blood and the revolving impeller. The new pump uses an impeller that is comparable to a flexible garden hose. If the free end of the hose were swung around in a circle like half of a jump rope, the fluid inside the hose would rotate and develop pressure even though the hose impeller itself did not "rotate"; therefore, no rotating shaft seal or internal bearings are required.     

Microspheres Based Detoxification System: A New Method in Convective Blood Purification

Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.     

Tissue perfusion in relation to cardiac output during continuous positive-pressure ventilation and administration of propranolol or verapamil

Background : Our objective was to determine whether administration of propranolol or verapamil modifies the hemodynamic adaptation to continuous positive-pressure ventilation (CPPV), in particular the regional distribution of cardiac output (CO).
Methods : General hemodynamics and regional blood flows assessed by microsphere technique (15 (μm) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H₂O end-expiratory pressure (CPPV8) before and after intravenous administration of propranolol (0.3 mg · kg⁻¹ followed by 0.15 mg · kg⁻¹ · h⁻¹, n=8) or verapamil (0.1 mg · kg⁻¹ followed by 0.3 mg · kg⁻¹ · h⁻¹, n=8).
Results : CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase.
Conclusions : The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO.     

Bariatric Surgery in Some "Central and East-European (former Eastern bloc)"Countries - Current Status and Prediction for the Next Millennium

Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.     

Volatile anaesthetics reduce adhesion of blood platelets under low-flow conditions in the coronary system of isolated guinea pig hearts

Background : Inhibitory effects of volatile anaesthetics on platelet aggregation have been demonstrated in several studies. However, the influence of volatile anaesthetics on intracoronary platelet adhesion has not been elucidated so far.
Methods : Isolated hearts of guinea pigs were perfused with buffer in the absence or presence of volatile anaesthetics (0.5 and 1 MAC) at constant coronary flow rates of 5 ml/min for 25 min, then 1 ml/min for 30 min and again 5 ml/min for 10 min. Before, during and after low-flow perfusion, a bolus of human platelets was applied into the coronary system. To simulate thrombogenic conditions, 0.3 U/ml human thrombin was infused during low-flow perfusion and reperfusion. The number of platelets sequestered to the endothelium was calculated from the difference between coronary in- and output of platelets. The myocardial production of lactate and consumption of pyruvate and coronary perfusion pressure were also determined.
Results : At a flow rate of 5 ml/min only about 3% of the applied platelets did not emerge from the coronary system, in any group. In contrast, 13.1±1.2% (mean±SEM) of infused platelets became adherent in low-flow perfusion in the control group without anaesthetic. The adherence was reduced with each 1 MAC isoflurane (to 6.2±1.2%), sevoflurane (to 4.4±0.9%) or halothane (to 3.2±1.5%) (each P <0.05 vs. control). Volatile anaesthetic, 0.5 MAC, did not inhibit platelet adhesion to a statistically significant extent in any case. Perfusion pressure and metabolic parameters were not statistically different between the control and the hearts exposed to anaesthetics.
Conclusion : Volatile anaesthetics in a concentration of 1 MAC can reduce the adhesion of platelets in the coronary system under reduced flow conditions. This action does not arise from vasodilation or inhibition of ischaemic stress.     

Synergistic interaction between the effects of propofol and midazolam with fentanyl on phrenic nerve activity in rabbits

Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg^?1 i. v. and 32 μg · kg^?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg^?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg^?1. The mean ED₅₀s, calculated from dose-response curves, were 5.4 mg · kg^?1, 3.9 μg · kg^?1 and 0.4 mg · kg^?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg^?1 and 8 μg · kg^?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration.     

Influence of dopexamine hydrochloride on haemodynamics and regulators of circulation in patients undergoing major abdominal surgery

Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg^?1 · min^?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min^?1 · m^?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO₂I) and oxygen consumption index (VO₂I) were also significantly increased in the dopexamine group (DO₂I: from 416±91 to 717±110 ml/m² · m²; VO₂I: from 98±25 to 157±22 ml/m² · m²), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow.     

Systemic analgesia adapted to the children's condition

A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.     

A comparison of the inhibitory effects of four volatile anaesthetics on the metabolism of chlorzoxazone, a substrate for CYP2E1, in rabbits

Background: Halothane inhibits in vitro and in vivo activity of cytochrome P-450 (CYP) 2E1. There are several fluorinated volatile anaesthetics besides halothane, and most of them are defluorinated by CYP2E1. It is unclear whether other fluorinated anaesthetics inhibit the in vivo activity of CYP2E1.
Methods: We compared the inhibitory effects of therapeutic concentrations of four inhalational anaesthetics, halothane, enflurane, isoflurane, and sevoflurane, on chlorzoxazone metabolism in rabbits receiving artificial ventilation.
Results: All four inhalational anaesthetics decreased arterial blood pressure and increased plasma chlorzoxazone concentration. However, no significant differences in the plasma chlorzoxazone concentration were found between the four anaesthetics. The estimated chlorzoxazone clearance increased after beginning inhalation with all four agents, but no significant difference in clearance was noted between agents.
Conclusions: At therapeutic concentrations, the in vivo inhibitory effect on chlorzoxazone metabolism was similar for all four inhalational anaesthetics examined, even though their chemical characteristics and extent of hepatic metabolism differ considerably.