Morgan-Ortíz F, Rodríquez-Ontiveros C, Chang-Bátiz H, Avila-Vergara M A
Departamento de Gincología y Obstetricia, Coordinación Universitaria del Hospital Civil, Culiacán, Sinaloa, México.
Ginecol Obstet Mex. 1997 Dec;65:529-32.
A comparison was made of ultrasonographic diagnosis of fetal nuchal encirclement by the umbilical cord versus the gold standard in pregnant, women at labor. 114 pregnant women at labor were studied. On admission to the labor and delivery room, each patient underwent an abdominal ultrasonographic evaluation for the identification of nuchal encirclement by the umbilical cord and the diagnosis by ultrasound was compared versus direct visualization of the umbilical cord at the moment of delivery or cesarean section (gold standard). Of the 114 patients studied, the prevalence of nuchal cord diagnosed by ultrasound was 20.1%. The diagnostic test had a sensitivity of 80% (CI 95%: 72.66-87.34), specificity of 96% (CI 95%:92.91-99.09), and positive and negative predictive values of 87% and 94% respectively. The accuracy of the test was 92%. Analysis of the discordances by the McNemar's test was not significative between obstetric ultrasound and the gold standard (p = 0.7236). The likelihood ratios were 20 and 0.20 for a positive and a negative results respectively. The ultrasonographic study during labor for diagnosis of nuchal encirclement by the umbilical cord had a high specificity (96%), and this advantage permit it to be utilized like screening test for the identification of high risk pregnancies with nuchal cord.
对临产妇经超声诊断胎儿脐带绕颈与金标准进行了比较。研究了114名临产妇。入院待产时，对每位患者进行腹部超声评估以确定脐带绕颈情况，并将超声诊断结果与分娩或剖宫产时直接观察脐带情况（金标准）进行比较。在研究的114名患者中，超声诊断脐带绕颈的患病率为20.1%。该诊断试验的敏感性为80%（95%置信区间：72.66 - 87.34），特异性为96%（95%置信区间：92.91 - 99.09），阳性预测值和阴性预测值分别为87%和94%。该试验的准确性为92%。经McNemar检验分析，产科超声与金标准之间的不一致性无统计学意义（p = 0.7236）。阳性和阴性结果的似然比分别为20和0.20。临产期超声检查诊断脐带绕颈具有较高的特异性（96%），这一优势使其可作为筛查试验用于识别有脐带绕颈的高危妊娠。
