Bechtel K, Bhende M, Venkataraman S, Allen J
Department of Pediatrics, Children's Hospital of Pittsburgh, PA, USA.
Ann Emerg Med. 1998 Mar;31(3):344-50. doi: 10.1016/s0196-0644(98)70345-2.
To determine the accuracy of the esophageal detector device (EDD) in predicting correct endotracheal tube (ETT) placement in a newborn-piglet model.
We used an EDD, comprising a 5-, 10- or 20-mL syringe attached to 4-mm tubing fitted to a 15-mm ETT adapter, to aspirate gas from cuffed or uncuffed ETTs placed in the trachea or esophagus of each newborn piglet. During aspiration, we noted any resistance encountered while pulling back the plunger of the syringe and recorded the total volume of gas aspirated into the syringe. A positive test, signifying tracheal ETT placement, was defined as the ability to freely aspirate gas without resistance and the aspiration of enough gas to fill the entire volume of the syringe. A negative test, signifying esophageal ETT placement, was defined as resistance encountered during the aspiration of gas into the syringe and rebound of the syringe plunger, leading to aspiration of a volume of gas less than the total volume of the syringe.
We conducted 444 trials (222 for uncuffed ETTs, 222 for cuffed ETTs). ETT size ranged from 3.0 to 4.5 mm. For cuffed ETTs, the 5-mL syringe had a sensitivity of 100% and a specificity of 5%, the 10-mL syringe had a sensitivity of 95% and a specificity of 16%, and the 20-mL syringe had a sensitivity of 86% and a specificity of 97%. For uncuffed ETTs, the 5-mL syringe had a sensitivity of 100% and a specificity of 5%, the 10-mL syringe had a sensitivity of 97% and a specificity of 24%, and the 20-mL syringe had a sensitivity of 81% and a specificity of 100%.
No syringe had 100% sensitivity and specificity in correctly predicting ETT placement. The 20-mL syringe had the highest combination of sensitivity and specificity. Further studies are warranted to determine whether the EDD using a 20-mL syringe would aid in the prediction of correct ETT placement in the pediatric population.
在新生仔猪模型中确定食管探测器装置（EDD）预测气管内导管（ETT）正确置入的准确性。
我们使用一种EDD，它由一个连接到4毫米 tubing 上的5毫升、10毫升或20毫升注射器组成，该 tubing 又连接到一个15毫米的ETT适配器上，用于从置于每只新生仔猪气管或食管内的带套囊或不带套囊的ETT中抽吸气体。在抽吸过程中，我们记录拉动注射器活塞时遇到的任何阻力，并记录吸入注射器的气体总体积。阳性测试表示ETT置于气管内，定义为能够无阻力地自由抽吸气体且抽吸的气体量足以充满整个注射器容积。阴性测试表示ETT置于食管内，定义为在向注射器内抽吸气体时遇到阻力且注射器活塞回弹，导致吸入的气体量小于注射器的总体积。
我们进行了444次试验（222次针对不带套囊的ETT，222次针对带套囊的ETT）。ETT尺寸范围为3.0至4.5毫米。对于带套囊的ETT，5毫升注射器的灵敏度为100%，特异性为5%；10毫升注射器的灵敏度为95%，特异性为16%；20毫升注射器的灵敏度为86%，特异性为97%。对于不带套囊的ETT，5毫升注射器的灵敏度为100%，特异性为5%；10毫升注射器的灵敏度为97%，特异性为24%；20毫升注射器的灵敏度为81%，特异性为100%。
没有一种注射器在正确预测ETT置入方面具有100%的灵敏度和特异性。20毫升注射器的灵敏度和特异性组合最高。有必要进一步研究以确定使用20毫升注射器的EDD是否有助于预测儿科人群中ETT的正确置入。
