单项超声测量指标预测临产胎儿体重

目的 :探讨应用胎儿小脑横径单项超声测量指标预测胎儿出生体重的临床价值。方法 :应用B型超声对 115例临产胎儿的小脑横径、双顶径、头围、腹围、股骨长度、肝脏长度、股骨中段皮下组织厚度、肾脏长径进行测量 ,并与新生儿体重的关系进行分析 ,将预测体重与实际体重进行比较 ,分析其误差。结果 :小脑横径与新生儿出生体重相关性好 ,其相关系数r =0 85 (P <0 0 0 1)。预测体重与实际体重绝对误差在± 2 0 0g内者占75 % ,相对误差 <± 5 %者占 6 5 %。结论 :应用超声测量胎儿小脑横径预测胎儿出生体重 ,方法简单准确 ,具有较好的临床实用价值 ,值得在临床上推广。     

Does Sonographic Determination of Placental Location Predict Fetal Birth Weight in Diamniotic‐Dichorionic Twins?

OBJECTIVE: The purpose of this study was to determine the association between placental location in diamniotic-dichorionic twins as determined at the time of anatomic survey and birth weight. METHODS: We retrospectively identified all diamniotic-dichorionic twins in our Maternal-Fetal Medicine sonography database between 2000 and 2005 who had an anatomic survey, went on to be delivered at our hospital, and had records available for review (n = 304). Placental location for each twin was determined at the time of anatomic survey and grouped into both anterior or both posterior versus separate anterior and posterior. Maternal and fetal characteristics were collected from chart review. Placental pathologic findings were available for 249 (83%) patients. Outcomes analyzed were percent discordance, small size for gestational age of twin A or B, and difference in birth weight as a continuous variable. Multivariable logistic regression using stepwise backward elimination was used to adjust for potential confounders. RESULTS: There was no difference in discordance of 20% or greater or incidence of small size for gestational age when both placentas were both anterior and both posterior compared with separate anterior and posterior: adjusted odds ratio (AdjOR), 1.38 (95% confidence interval [CI], 0.64-2.95); and AdjOR, 1.29 (95% CI, 0.57-2.89). The actual birth weight difference (A - B) was not affected by placental location (P = .36). Opposite sex fetuses and nulliparity were significantly associated with birth weight discordance: AdjOR, 2.68 (95% CI, 1.39-5.17); and AdjOR, 0.34 (95% CI, 0.28-0.94). CONCLUSIONS: We did not find a correlation between birth weight and placental location in our cohort analysis. The presence of sex-discordant twins was associated with birth weight discordance of 20% or greater, whereas nulliparity was protective.     

极低出生体质量儿用氧方式对早产儿视网膜病变的影响

目的 探索极低出生体质量儿不同用氧方式对早产儿视网膜病变(retinopathy of prematurity,ROP)发生的影响,以便更安全地选择用氧方式,减少ROP的发生.方法 回顾分析极低出生体质量儿用氧护理信息,收集2005年1月-2008年7月全部极低出生体质量儿的病历资料,重点记录用氧方式包括给氧途径、时间、浓度,比较不同用氧方式患儿ROP的发生率,以发现可能存在的高危因素.应用SPSS 13.0统计软件进行数据处理,运用统计学描述和确切概率检验.结果 应用头罩吸氧方式者与未应用者相比,ROP发生率更高(P=0.012);应用机械通气者较未应用者ROP发生率更高(P=0.011).结论 头罩吸氧较其他吸氧方式ROP发生可能性更高,建议在早产儿特别是极低出生体质量儿不选用头罩吸氧方式;机械通气是发生ROP的高危因素,选择应用时应慎重;极低出生体质量儿的用氧安全浓度是否应该低于一般早产儿,是一个值得关注的问题.     

Understanding the Implications of Birth Weight

Neonatal growth parameters include birth weight, length, and head circumference. Weight, as it relates to gestational age, is monitored closely during pregnancy to assess the appropriate growth of the fetus. At birth, it becomes an important parameter to assess the health and well-being of the newborn. Birth weight carries implications for nursing care and monitoring of the newborn’s transition to extrauterine life. The importance of birth weight assessment and its interpretation will be reviewed, along with the implications for immediate neonatal care and potential long-term effects on an infant’s health outcomes.     

分时段中心静脉置管在极低出生体质量儿中的应用

目的探讨分时段脐静脉置管和经外周静脉置入中心静脉导管(peripherally inserted central catheter,PICC)置管在极低出生体质量儿中的应用效果。方法选取2010年1月—2011年12月入院的极低出生体质量儿111例,分为分时段应用脐静脉置管、PICC组（观察组）51例和外周静脉置管加PICC组（对照组）60例,监测两组住院期间的静脉置管情况、患儿身体指征反应及导管感染情况。结果观察组PICC 1次置管成功率高于对照组,输液外渗发生率低（P<0.01）;两组患儿纠正低血糖所需时间差异无统计学意义;呼吸暂停次数、体质量增长至2 kg时间经比较差异有统计学意义（P<0.01）。结论采用分时段中心静脉置管具有穿刺成功率高,留置时间长,输液外渗发生率低,且不增加感染的优点,能最大限度发挥中心静脉置管的优势,为极低出生体质量儿提供了安全有效的静脉治疗通道,值得在临床中推广应用。     

极/超低出生体质量儿经外周静脉置入中心静脉导管相关并发症及影响因素分析

目的调查极/超低出生体质量儿经外周静脉置入中心静脉导管(peripherally inserted central venous catheters,PICC)相关并发症的发生情况,探讨PICC相关并发症的影响因素。方法便利抽样法选取北京市某三级甲等综合医院新生儿重症监护病房收治的极低和超低出生体质量儿为研究对象,分析其PICC相关并发症的发生情况及影响因素。结果本研究共纳人360例极低和超低出生体质量儿,其中有49例极/超低出生体质量儿发生PICC相关并发症,发生率为13.6%。Logistic回归分析显示,胎龄<30周的早产儿发生PICC导管相关并发症的风险是胎龄≥30周的2.39倍;正中静脉/头静脉、大隐静脉/颞浅静脉置管发生并发症的风险分别是腋静脉置管的12.32倍和9.85倍。结论极低或超低出生体质量儿推荐考虑腋静脉和贵要静脉作为PICC置管的穿刺静脉;在导管维护过程中应保证及时有效的指标监测,以降低导管相关并发症的发生风险。     

Suboptimal Second‐Trimester Ultrasonographic Visualization of the Fetal Heart in Obese Women

OBJECTIVE: The purpose of this study was to determine whether a repeated antenatal ultrasound examination improves fetal cardiac visualization for the obese and nonobese population. METHODS: A computerized ultrasound database (October 1999-June 2003) was used to identify singleton pregnancies undergoing repeated prenatal ultrasound examinations because of initial suboptimal ultrasonographic visualization (SUV) of the 4-chamber view, outflow tracts, or both. Women with maternal diabetes, abnormal maternal serum screening results, or known fetal anomalies at the initial examination were excluded. Patients were classified by maternal body mass index (BMI): less than 30 kg/mg2 (nonobese), 30 to 34.9 kg/mg2 (class I obesity), 35 to 39.9 kg/mg2 (class II obesity), and 40 kg/mg2 or greater (morbid obesity). The association between maternal BMI and SUV of the fetal heart was analyzed. RESULTS: Three hundred seventy-two patients were abstracted from the database. The median gestational age was 19.0 weeks at the initial visit (range, 18.0-21.9 weeks) and 21.4 weeks at the second visit (range, 18.9-23.9 weeks). The median BMI was 32.6 kg/m2 (range, 16.4-58.7 kg/m2). Sixty-three percent of patients were obese (BMI >or=30). Cardiac anatomy continued to have SUV in 11% of the women. The rate of SUV was associated with the obesity class (1.5% for nonobese, 12% for obesity I, 17% for obesity II, and 20% for morbid obesity; P < .0001). A cardiac anomaly was found in 1 of 372 repeated examinations (arteriovenous canal defect) for a patient with BMI of 24.8 kg/m2. CONCLUSIONS: Repeated ultrasound examination for SUV of the fetal heart at a later gestational age dramatically reduces SUV. However, obese patients continue to have much higher rates of persistent SUV.     

A Method for Assessing the Microvasculature in a Murine Tumor Model Using Contrast‐Enhanced Ultrasonography

Objective. The purpose of this study was to develop a method for assessing tumor vascularity in a preclinical model of breast cancer using contrast‐enhanced ultrasonography. Methods. Eight mice were injected with 67NR breast cancer cells on their hind limbs and imaged with ultrasonography 8 days later. Mice were injected with an ultrasound contrast agent (UCA), and a sequence of images of the resultant backscattered echoes was recorded before and after high‐power “destruction” pulses for each of multiple parallel planes. From these, data maps of the maximum contrast enhancement (within each time course) were constructed for each pixel, which enabled reconstruction of high‐resolution coregistered sections into a 3‐dimensional (3D) volume reflecting tumor vascularity. Additional studies were performed to determine the duration and repeatability of image enhancement, and images were correlated with conventional 3D power Doppler measurements. Results. The lifetime of the UCA in vivo was found to be 4.3 ± 1.09 minutes (mean ± SD). The 3D contrast‐enhanced ultrasonographic technique produced images that correlated well with power Doppler images in specific regions but also depicted additional regions of flow surrounding the power Doppler signal. The mean correlation coefficient between voxel measurements of the central slice for each animal was 0.64 ± 0.07 (P < .01). In addition, sequential studies in each animal were reproducible. Conclusions. A method producing high‐resolution volumetric assessments of tumor vascularity in a preclinical model of breast cancer is shown that correlates with other ultrasonographic measures of blood flow, which may provide greater sensitivity to the microvasculature.     

Application of 3‐Dimensional Ultrasonography to Imaging the Fetal Anal Canal

Objective. Ultrasonography has been applied previously to the assessment of the fetal anal canal. We aimed to examine the potential of 3‐dimensional ultrasonography (3DUS) in the evaluation of the fetal anal canal and to obtain normal fetal anal canal measurements. Methods. Patients were recruited from an unselected population of gravidas with known gestational age (by dates or first‐trimester ultrasonography) and without known fetal anomalies presenting for fetal evaluation in the ultrasound units of 2 tertiary care centers between 16 and 39 gestational weeks. In addition to the ordered scan, 3DUS imaging of the fetal anal canal was performed. Transverse and sagittal views and volumes were obtained. Measurements of the fetal anal canal anteroposterior diameter, lateral diameter, and length were performed in transverse and sagittal planes, respectively, and scatterplots of these dimensions were created. Measurements were performed and repeated on raw data sets by 2 independent observers, and the results were analyzed to estimate interobserver and intraobserver reliability. Results. A total of 186 patients were examined for this study at 16 to 39 weeks' gestation (mean, 27.4 weeks). The anteroposterior diameter of the fetal anal canal in this study group ranged from 4 to 21 mm (mean, 11.2 mm; SD, ±3.5 mm), whereas the lateral diameter ranged from 7 to 18 mm (mean, 9.1 mm; SD, ±3.0 mm). The length of the fetal anal canal in this study group ranged from 3 to 24 mm (mean, 14.3 mm; SD, ±3.8 mm). Conclusions. Ultrasonographic assessment of the fetal anal canal with 3DUS is feasible. Scatterplots were created for internal anal sphincter width and length measurements from 16 to 39 weeks' gestation. Larger studies are necessary to establish nomograms of these measurements and their application to the evaluation of pathologic cases. We speculate that 3DUS assessment of the fetal anal canal may improve detection rates of disorders involving this system.