Blaivas Michael, Lyon Matthew, Duggal Sandeep
Section of Emergency Ultrasound, Department of Emergency Medicine, Medical College of Georgia, Augusta, GA 30912-4007, USA.
Acad Emerg Med. 2005 Sep;12(9):844-9. doi: 10.1197/j.aem.2005.05.005.
Supine anteroposterior (AP) chest radiography may not detect the presence of a small or medium pneumothorax (PTX) in trauma patients.
To compare the sensitivity and specificity of bedside ultrasound (US) in the emergency department (ED) with supine portable AP chest radiography for the detection of PTX in trauma patients, and to determine whether US can grade the size of the PTX.
This was a prospective, single-blinded study with convenience sampling, based on researcher availability, of blunt trauma patients at a Level 1 trauma center with an annual census of 75,000 patients. Enrollment criteria were adult trauma patients receiving computed tomography (CT) of the abdomen and pelvis (which includes lung windows at the authors' institution). Patients in whom the examination could not be completed were excluded. During the initial evaluation, attending emergency physicians performed bedside trauma US examinations to determine the presence of a sliding lung sign to rule out PTX. Portable, supine AP chest radiographs were evaluated by an attending trauma physician, blinded to the results of the thoracic US. The CT results (used as the criterion standard), or air release on chest tube placement, were compared with US and chest radiograph findings. Sensitivities and specificities with 95% confidence intervals (95% CIs) were calculated for US and AP chest radiography for the detection of PTX, and Spearman's rank correlation was used to evaluate for the ability of US to predict the size of the PTX on CT.
A total of 176 patients were enrolled in the study over an eight-month period. Twelve patients had a chest tube placed prior to CT. Pneumothorax was detected in 53 (30%) patients by US, and 40 (23%) by chest radiography. There were 53 (30%) true positives by CT or on chest tube placement. The sensitivity for chest radiography was 75.5% (95% CI = 61.7% to 86.2%) and the specificity was 100% (95% CI = 97.1% to 100%). The sensitivity for US was 98.1% (95% CI = 89.9% to 99.9%) and the specificity was 99.2% (95% CI = 95.6% to 99.9%). The positive likelihood ratio for a PTX was 121. Spearman's rank correlation showed at rho of 0.82.
With CT as the criterion standard, US is more sensitive than flat AP chest radiography in the diagnosis of traumatic PTX. Furthermore, US allowed sonologists to differentiate between small, medium, and large PTXs with good agreement with CT results.
仰卧前后位胸部X线摄影可能无法检测出创伤患者中存在的小或中等大小的气胸。
比较急诊科床边超声（US）与仰卧便携式胸部前后位X线摄影对创伤患者气胸检测的敏感性和特异性，并确定超声是否能够对气胸大小进行分级。
这是一项前瞻性、单盲研究，采用方便抽样，基于研究人员的可用性，选取一家年接诊量为75000例患者的一级创伤中心的钝性创伤患者。纳入标准为接受腹部和骨盆计算机断层扫描（CT）（在作者所在机构包括肺部窗位）的成年创伤患者。无法完成检查的患者被排除。在初始评估期间，主治急诊医师进行床边创伤超声检查以确定是否存在肺滑动征以排除气胸。便携式仰卧前后位胸部X线片由一位对胸部超声结果不知情的主治创伤医师进行评估。将CT结果（用作标准参照）或胸腔置管时的气体排出情况与超声和胸部X线片检查结果进行比较。计算超声和胸部X线摄影检测气胸的敏感性和特异性以及95%置信区间（95%CI），并使用Spearman等级相关性评估超声预测CT上气胸大小的能力。
在八个月的时间里，共有176例患者纳入研究。12例患者在CT检查前已进行胸腔置管。超声检测到53例（30%）患者存在气胸，胸部X线摄影检测到40例（23%）。通过CT或胸腔置管确定有53例（30%）真阳性。胸部X线摄影的敏感性为75.5%（95%CI = 61.7%至86.2%），特异性为100%（95%CI = 97.1%至100%）。超声的敏感性为98.1%（95%CI = 89.9%至99.9%），特异性为99.2%（95%CI = 95.6%至99.9%）。气胸的阳性似然比为121。Spearman等级相关性显示rho为0.82。
以CT作为标准参照，超声在诊断创伤性气胸中比胸部前后位平片更敏感。此外，超声使超声科医生能够区分小、中、大气胸，与CT结果有良好的一致性。
