Schlager D, Sanders A B, Wiggins D, Boren W
Section of Emergency Medicine, College of Medicine, University of Arizona, Tucson 85724.
Ann Emerg Med. 1991 Feb;20(2):189-91. doi: 10.1016/s0196-0644(05)81220-x.
To determine the ability of an emergency physician to detect a variety of foreign bodies in an experimental model using a portable ultrasound device.
Ten pieces of beef were sliced into cubes approximately 6 cm on each side. Six different groups of foreign bodies were examined: gravel, cactus spine, glass, metal, wood, and plastic. An independent observer placed the objects in a random fashion into the beef cubes. One hundred twenty observations were made using sets of ten beef cubes at a time. Five foreign bodies were placed into each set of ten beef cubes.
A blinded emergency physician used a portable ultrasound with a 7.5-MHz transducer to determine the presence or absence of a foreign body in each cube.
Ultrasound detected 59 of 60 foreign bodies, including all cubes of meat embedded with gravel, cactus spine, plastic, metal, and wood. Glass was detected nine of ten times. Of the 60 cubes of meat with no foreign bodies, one false-positive was recorded. This yielded sensitivity, specificity, positive predictive value, and negative predictive value of 98%. Positive determinations by ultrasound were significantly greater in the meat cubes with foreign bodies compared with the control group with no foreign bodies (P less than .001 by chi 2). Although the subset of glass foreign bodies had one false-positive and one false-negative, it was not significantly different in comparison with the other groups (P greater than .05 by chi 2).
Ultrasound has promise as a diagnostic tool for the detection of a variety of foreign bodies. Further clinical studies using ultrasound for the detection of foreign bodies are warranted.
使用便携式超声设备，确定急诊医生在实验模型中检测各种异物的能力。
将十块牛肉切成边长约6厘米的立方体。检查六组不同的异物：砾石、仙人掌刺、玻璃、金属、木头和塑料。一名独立观察者将这些物体随机放入牛肉立方体中。每次使用十块牛肉立方体进行120次观察。每组十块牛肉立方体中放置五个异物。
一名不知情的急诊医生使用带有7.5兆赫换能器的便携式超声，确定每个立方体中是否存在异物。
超声检测出60个异物中的59个，包括所有嵌入砾石、仙人掌刺、塑料、金属和木头的肉块。玻璃检测出十次中的九次。在60个没有异物的肉块中，记录到一次假阳性。这得出的敏感性、特异性、阳性预测值和阴性预测值为98%。与没有异物的对照组相比，有异物的肉块中超声阳性判定显著更多（卡方检验P<0.001）。虽然玻璃异物子集中有一次假阳性和一次假阴性，但与其他组相比无显著差异（卡方检验P>0.05）。
超声有望成为检测各种异物的诊断工具。有必要进一步开展使用超声检测异物的临床研究。
