儿科重症监护病房中影响机械通气成功的相关因素

目的 探讨儿科重症监护病房(PICU)中影响机械通气成功的相关因素。方法 将lll例行机械通气的危重病儿分成治疗成功组与失败组，对其相关因素进行回顾性分析。结果两组患儿在上机前危重病例评分、是否伴有心跳呼吸骤停和(或)休克及并发多系统器官功能衰竭(MODS)等方面差异有权显著意义(P＜0．001)；超过48h的机械通气患儿是否继发呼吸机相关肺炎(VAP)亦有显著意义(P＜0.05)。结论 PICU中影响机械通气成功率的因素主要是原发病的性质及严重程度，并与MODS与VAP有密切关系。     

小剂量芬太尼在机械通气中的应用

目的　 了解机械通气患儿以小剂量芬太尼持续静脉滴注的作用。 方法 　观察用药前后呼吸顺应性 (Cdyn)、气道阻力 (Raw)及呼气末二氧化碳分压 (PetCO2 )的变化。 结果 　 1个月～ 3岁患儿用药前后Raw及PetCO2 明显下降 ,肺部感染患儿指标变化显著大于非感染患儿 ,Cdyn用药前后均未发现显著差异。 结论 　提示机械通气中用小剂量芬太尼可以减轻人机对抗 ,降低气道压 ,改善肺气体交换及肺功能 ,有利于患儿顺利地渡过危险期     

气道闭合压P0.1在小儿机械通气中的临床价值

目的探讨气道闭合压(P0.1)在小儿机械通气中的临床价值.方法对收住儿童ICU的呼吸衰竭上呼吸机的患儿,分别于上呼吸机第一天和撤机时(中枢性呼吸衰竭放弃治疗的那一天)测气道闭合压(P0.1).结果在外周型呼吸衰竭患儿,0～1岁组、1～3岁组和3岁以上组,P0.1在撒机时与上呼吸机第一天比较均有显著的统计学差异(P＜0.001或0.001＜P＜0.05).结论在机械通气中,检测Po.1的动态变化,可了解患儿的病情变化,指导呼吸机参数的调节,为临床小儿呼吸机的成功撤离提供了有关肺功能的预测指标.     

Mechanical Loading Stimulates Differentiation of Periodontal Osteoblasts in a Mouse Osteoinduction Model: Effect on Type I Collagen and Alkaline Phosphatase Genes

The effects of mechanical loading on the osteoblast phenotype remain unclear because of many variables inherent to the current experimental models. This study reports on utilization of a mouse tooth movement model and a semiquantitative video image analysis of in situ hybridization to determine the effect of mechanical loading on cell-specific expression of type I collagen (collagen I) and alkaline phosphatase (ALP) genes in periodontal osteoblasts, using nonosseous cells as an internal standard. The histomorphometric analysis showed intense osteoid deposition after 3 days of treatment, confirming the osteoinductive nature of the mechanical signal. The results of in situ hybridization showed that in control periodontal sites both collagen I and ALP mRNAs were expressed uniformly across the periodontium. Treatment for 24 hours enhanced the ALP mRNA level about twofold over controls and maintained that level of stimulation after 6 days. In contrast, collagen I mRNA level was not affected after 24 hours of treatment, but it was stimulated 2.8-fold at day 6. This increase reflected enhanced gene expression in individual osteoblasts, since the increase in osteoblast number was small. These results indicate that (1) the mouse model and a semiquantitative video image analysis are suitable for detecting osteoblast-specific gene regulation by mechanical loading; (2) osteogenic mechanical stress induces deposition of bone matrix primarily by stimulating differentiation of osteoblasts, and, to a lesser extent, by an increase in number of these cells; (3) ALP is an early marker of mechanically-induced differentiation of osteoblasts. (4) osteogenic mechanical stimulation in vivo produces a cell-specific 2.8-fold increase in collagen gene expression in mature, matrix-depositing osteoblasts located on the bone surface and within the osteoid layer. Received: 9 August 1999 / Accepted: 4 February 2000     

Early increase of TNFα and IL-6 in tracheobronchial aspirate fluid indicator of subsequent chronic lung disease in preterm infants

AIM—To investigate if early changes in concentrations of proinflammatory cytokines in tracheobronchial aspirate fluid (TAF) from preterm infants could be used to detect infants at risk of chronic lung disease (CLD) and help in the selection of patients for early steroid treatment.METHODS—Twenty eight preterm infants less than 34 weeks of gestation (median 26 weeks) were intubated and daily measurements of TAF concentrations of tumour necrosis factor α (TNFα) and the interleukins IL-1β, IL-6, and IL-8 were made, using enzyme immunoassay techniques.RESULTS—Seventeen of the infants developed CLD. The infants who developed CLD had significantly increased concentrations of TNFα, IL-1ß, IL-6 on days 2 and 3. TNFα, IL-6, and IL-8 concentrations were significantly related to gestational age and duration of supplemental oxygen; TNFα, IL-6, and IL-8 concentrations also correlated with length of time on the ventilator.CONCLUSION—These data indicate that tracheobronchial aspirate fluid cytokine concentrations may be used as a predictor of subsequent CLD and may help select a group of preterm infants at high risk of developing CLD for early treatment.     

机械通气患者下呼吸道感染抗生素治疗的临床观察

目的：探讨机械通气患者并发下呼吸道感染菌群变化规律，方法：将机械通气患者49例，且通气时间48h以上者，每日查痰培养，隔日照X线胸片，记录痰培养致病菌出现时间规则使用抗生素，直至脱机时的变化规律。结果：以革兰阴性杆菌致病几率为最高，其次为革兰阳性菌、金黄色葡萄球菌及肠球杆菌。发病至气管吸痰细菌培养阳性的时间表明，机械通气〈4d，痰培养阳性率为15％（3例／20例）；5～6d者达50％（4例／8例）；超过7d者，痰培养阳性率100％（n=21）。结论：本观察表明机械通气患者并发下呼吸道感染的防治中，加强呼吸道管理，防止交互感染，合理使用抗生素，对患者的预后是不可忽视的。     

Mechanical Accuracy of a New Stereotactic Guide

Summary ? Objective. A new stereotactic guide using a navigational computer is developed for stereotactic procedures. In order to compare the mechanical accuracy of the guide to frame based systems, an error analysis study was designed.  Methods. A biopsy procedure was simulated using a phantom model. Targets with known co-ordinates in a three-dimensional Cartesian co-ordinate system were positioned inside the skull model. A biopsy needle was inserted along computer set trajectories from three different entry points. The position of the biopsy needle in the co-ordinate system was measured. Distance from needle tip to target was calculated and defined as the error of the system for each trial. The results were statistically analyzed for precision and biasedness.  Results. A total of 242 accuracy measurements (182 on two MRI scans, 60 on one CT scan) were carried out. Mean incision length along the trajectories was 59 mm. Mean error using MRI scans was 3.8 mm and for the CT scan 2.9 mm. The error of the stereotactic computer was found to be 1.0 mm with both MR and CT imaging. The main cause of error for the MRI based trials was distortion of the magnetic field.  Conclusion. The results indicate a stereotactic system with high degree of accuracy. This is confirmed by a clinical study of 39 biopsies where all tumours were reached. MRI affected the mechanical accuracy significantly due to distortion of the magnetic field. The accuracy is comparable to other studies performed on both stereotactic computers and frame based systems.     

呼吸机治疗新生儿肺透明膜病预后多因素分析

目的分析呼吸机治疗新生儿肺透明膜病(HMD)的疗效及影响预后的因素。方法对2000年1月~2002年12月在我科NICU呼吸机治疗的54例HMD患儿进行总结,分析其疗效,比较治愈组与病死组胎龄、出生体重、上机日龄、上机前血气及吸气峰压(PIP)、呼吸未正压(PEEP)、各种并发症的差异。结果呼吸机治疗新生儿HMD的治愈率为68.4％;病死组胎龄、出生体重均明显低于治愈组(P<0.05),病死组上机时的日龄及上机前的血pH值均明显小于治愈组(P<0.01),病死组呼吸机参数PIP、PEEP均明显高于治愈组(P<0.05),两组间各种并发症的比较差异无显著性。结论呼吸机是治疗新生儿HMD的主要手段;HMD患儿胎龄越小,体重越低,则病变发生越早,上机前酸中毒越明显,病死率就越高。     

新生儿机械通气后远期肺功能随访

目的　了解新生儿机械通气对远期肺功能及反复呼吸道疾病影响。方法　新生儿期用呼吸机治疗16例患儿 ,8年后对其进行随访 ,并作肺功能检测。结果　 5 0 %患儿有反复呼吸道疾病症状 ,75 %患儿肺功能异常 ,其中残气量 /肺总量 (RV/TLC)为 5 6 .2 5 %、肺活量 2 5 %时最大呼气流量 (Vmax 2 5 )为 4 3.7%、特殊呼吸道阻力 (sRaw)及特殊呼吸道传导 (sGaw)均为 5 0 %。吸气峰压 (PIP) >2 5cmH2 O组用力肺活量中期平均呼气流速 (FEF 2 5 %～ 75 % )及 5 0 %用力肺活量时的最大呼气流速 (Vmax 5 0 )低于PIP <2 5cmH2 O组。呼气末正压 (PEEP)≤ 4cmH2 O组sRaw >4cmH2 O组。结论　新生儿机械通气可影响远期肺功能。较高PIP或过低PEEP可引起肺损伤 ,从而引起呼吸道阻力增加 ,呼吸道高反应。而儿童期反复呼吸道疾病可能与肺损伤后支气管反应性增高有关     

早产儿肺出血机械通气治疗探讨

目的:探讨低机械通气参数治疗早产儿肺出血的疗效及应用价值。方法:将96例肺出血早产儿随机分为较低机械通气参数(IPPV+PEEP)治疗组和常频机械通气参数(IPPV+PEEP)对照组,并对结果进行统计学分析。结果:治疗组52例肺出血早产儿中存活45例,死亡6例,放弃治疗1例;对照组44例肺出血早产儿中存活27例,死亡11例,放弃治疗6例。存活者平均机械通气治疗时间79h(最短10h,最长120h)。结论:采用机械通气能显著提高早产儿肺出血治愈率,可大大降低早产儿肺出血的死亡率。低机械通气参数比常频机械通气参数优越。