Ultrasound Detects Pneumothorax as Effectively as CT
The January issue of Chest includes a report from Italian researchers which indicates that occult traumatic pneumothorax (PTX), can be detected with lung ultrasound. As well, findings from this modality appear to be almost as accurate as those procured with computed tomography (CT).
The team completed a study over a year and a half to quantitatively compared the accuracy of lung ultrasound for diagnosis of PTX to both CT lung scanning and chest radiography. The team recruited 109 patients who were admitted to the emergency department for chest trauma or polytrauma. All the patients were spontaneously breathing and conscious.
The research team noted the downsides associated with CT scanning. One such concern with this patient population, in which many are acutely ill, is transporting patients who are not completely stable to the radiology suite to undergo scanning. A secondary consideration that makes CT a less appealing diagnostic tool is the high amount of radiation exposure.
A total of 25 PTXs were diagnosed in the 218 total hemithoraxes that underwent assessment. Just over half (52 percent) were detected with simple chest x-ray, while 92 percent were noted with lung ultrasound. Lung ultrasound yielded only one false positive. The sensitivity and specificity of lung ultrasound determined were 92 and 99.4 percent, respectively.
Another key piece of data usually collected with CT, pneumothorax extension, was noted to be fairly accurate with lung ultrasonography. In eighty percent of the cases, findings from CT and ultrasound were consistent with respect to PTX extension. The difference between the two was, on average, 1.9 centimeters.
The research team suggests that lung ultrasound should be completed as part of the primary survey, included into the focused assessment with sonography for trauma (FAST), when patients are treated for traumatic injury. The tool appears to be as effective as CT in detecting occult pneumothorax. If further imaging is required, patients can be referred for CT scans after they have been stabilized.
February 8, 2008 Related topics: Imaging, Diagnostic, Surgery, Emergency