Diagnostic Accuracy of Ultrasonography in the Acute Assessment of Common Thoracic Lesions After Trauma

CHEST Original ResearchCRITICAL CARE

www.chestpubs.org CHEST / 141 / 5 / MAY, 2012 1177

Pneumothoraces, hemothoraces, and lung contu-sions are common after chest trauma, but they

can be life-threatening if not promptly recognized in the ED. 1,2 The acute assessment of a patient with chest trauma usually includes a clinical examination (CE) and bedside chest radiography (CXR). Such patients are usually managed in the supine position with spinal immobilization, which underestimates the prevalence of these thoracic lesions in compar-ison with diagnosis with thoracic CT scan. 3,4 However, thoracic CT scanning raises problems for radiation exposure, cost, and transport of unstable high-risk patients. 5

Thoracic ultrasonography appears to be the opti-mal bedside diagnostic modality, with a growing body of evidence supporting its use after chest trauma in the diagnosis of pneumothorax, 6-13 hemothorax, 14,15 and lung contusion. 16 Although these studies reported a greater sensitivity of thoracic ultrasonography over that of CXR, 17 they assessed the performance of tho-racic ultrasonography in the diagnosis of one pre-defi ned thoracic lesion. Our study aimed to assess the ability of thoracic ultrasonography to detect, on arrival, the occurrence of common thoracic lesions (ie, pneumothorax, hemothorax, and/or lung contu-sion) in a cohort of chest trauma patients admitted to

Background: The accuracy of combined clinical examination (CE) and chest radiography (CXR) (CE 1 CXR) vs thoracic ultrasonography in the acute assessment of pneumothorax, hemothorax, and lung contusion in chest trauma patients is unknown. Methods: We conducted a prospective, observational cohort study involving 119 adult patients admitted to the ED with thoracic trauma. Each patient, secured onto a vacuum mattress, underwent a subsequent thoracic CT scan after fi rst receiving CE, CXR, and thoracic ultrasonography. The diagnostic performance of each method was also evaluated in a subgroup of 35 patients with hemodynamic and/or respiratory instability. Results: Of the 237 lung fi elds included in the study, we observed 53 pneumothoraces, 35 hemotho-races, and 147 lung contusions, according to either thoracic CT scan or thoracic decompression if placed before the CT scan. The diagnostic performance of ultrasonography was higher than that of CE 1 CXR, as shown by their respective areas under the receiver operating characteristic curves (AUC-ROC): mean 0.75 (95% CI, 0.67-0.83) vs 0.62 (0.54-0.70) in pneumothorax cases and 0.73 (0.67-0.80) vs 0.66 (0.61-0.72) for lung contusions, respectively (all P , .05). In addition, the diagnostic performance of ultrasonography to detect pneumothorax was enhanced in the most severely injured patients: 0.86 (0.73-0.98) vs 0.70 (0.61-0.80) with CE 1 CXR. No difference between modalities was found for hemothorax. Conclusions: Thoracic ultrasonography as a bedside diagnostic modality is a better diagnostic test than CE and CXR in comparison with CT scanning when evaluating supine chest trauma patients in the emergency setting, particularly for diagnosing pneumothoraces and lung contusions. CHEST 2012; 141(5):1177–1183

Abbreviations: AIS 5 Abbreviated Injury Scale; AUC-ROC 5 area under the receiver operating characteristic curve; CE 5 clinical examination; CXR 5 chest radiograph; GCS 5 Glasgow Coma Scale; ISS 5 Injury Severity Score; MV 5 mech-anical ventilation; SABP 5 systolic arterial BP; SAPS II 5 Simplifi ed Acute Physiology Score II; SOFA 5 Sequential Organ Failure Assessment

Diagnostic Accuracy of Ultrasonography in the Acute Assessment of Common Thoracic Lesions After Trauma Anne-Claire Hyacinthe , MD ; Christophe Broux , MD ; Gilles Francony , MD ; Céline Genty , BSc ; Pierre Bouzat , MD ; Claude Jacquot , MD ; Pierre Albaladejo , MD , PhD ; Gilbert R. Ferretti , MD , PhD ; Jean-Luc Bosson , MD , PhD; and Jean-François Payen , MD , PhD

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1178 Original Research

(curvature 40R, fi eld-of-view 75°), by one of three trained operators (A.-C. H., C. B., and G. F.), each with at least 50 thoracic ultraso-nography experiences and blinded to the CE and CXR results. The abdominal probe was used as part of ultrasonography pro-tocol for multiple trauma patients. 9 Pneumothorax, hemotho-rax, and lung contusion were sought according to the approach described by Lichtenstein. 19 The upper, middle, and lower parts of the anterior and lateral regions of the two chest walls were sequentially examined with the patient in the supine position. The posterior part of the chest was not explored because all patients were immobilized on a vacuum mattress until spinal trauma was excluded by CT scan. After localizing the diaphragm and lungs, conventional two-dimensional imaging was used to check in B-mode lung sliding and pleural effusion, B-lines, lung point, and lung consolidation, in this respective order.

Pneumothorax was defi ned by the absence of lung sliding (or lung pulse) with A-lines and by the presence of lung point ( Fig 1 ). Hemothorax was defi ned by dependent collection between the diaphragm and the pleura with inspiratory movement of the visceral pleura from depth to superfi cies (sinusoid sign) ( Fig 2 ). A lung contusion was diagnosed by the presence of the following: (1) an irregularly delineated tissue image, which could be a mod-erately hypoechoic blurred lesion with no change during respi-raztion or hyperechoic punctiform images corresponding to air bronchogram; (2) multiple B-lines ( Fig 2 ). The ultrasound oper-ator recorded each thoracic lesion assessment using the proba-bility diagnosis scale (0-3). Thoracic ultrasonography results could be disclosed to the physician in charge of the trauma patient, however, if patient had abnormal vital signs and required imme-diate diagnosis.

Thoracic CT Scan

Each patient, once stabilized, was transported to the radi-ology department. Thoracic CT scans were performed from the apex of the chest to the diaphragm, with the patient in the supine position (Somatom Sensation 16; Siemens Medical Systems) (e-Appendix 2). Thoracic CT scan was interpreted retrospectively by an independent radiologist who was blinded to the results from the former investigations (CE 1 CXR and ultrasonography).

In patients requiring immediate chest tube placement prior to CT scan, chest tube with no cutting end was placed after CXR and thoracic ultrasonography. The diagnosis of either pneu-mothorax and/or hemothorax was then confi rmed if air bubbles or blood (at least 100 mL) appeared in the chest tube with no worsening of the patient’s clinical condition.

Statistical Analysis

Variables were expressed as frequency and percentage, and median and interquartile range (ie, 25th and 75th percentiles). The accuracy of each method (CE 1 CXR, ultrasonography) in diagnosing thoracic lesions using CT scan (or chest drain) as the reference method was expressed using sensitivity, specifi city, and likelihood ratios, according to a probability diagnosis scale score of 2 or 3. The diagnosis performance of each method was then evaluated using the area under the receiver operating characteristic curve (AUC-ROC) (mean, 95% CI). The AUC-ROC curves of the two diagnostic modalities (CE 1 CXR, ultrasound) were compared using a test for dependent receiver operating characteristic curves (same sample). 20 The independence between right and left chest walls in the occurrence of each thoracic lesion was tested using the x 2 test. We also tested the interobserver variability between the three ultrasound operators by comparing their AUC-ROC curves for the three thoracic lesions. Statistical analysis was performed using Stata version 10.0 (Stata Corp). Statistical signif-icance was declared when P � .05.

the ED. We prospectively compared the diagnostic performance of combined CE and CXR (CE 1 CXR) vs thoracic ultrasonography, using thoracic CT scan (or chest drain if placed prior to the CT scan) as the gold standard. In addition, the diagnostic perfor-mance of each method was evaluated in a subgroup of patients with hemodynamic and/or respiratory instability.

Materials and Methods

Patients

This prospective observational cohort study was conducted from November 2005 to April 2007 in the ED at the University Hospital of Grenoble level 1 trauma center. The Regional Institu-tional Ethics Committee approved the design of the study and waived requirements for informed consent from the patients (registration number #5891). Patients were included if their admission to the ED indicated a thoracic CT scan within 6 h of their initial trauma and required CE, CXR, and thoracic ultraso-nography no more than 90 min before the CT examination. Pneumo-thorax, hemothorax, and lung contusion were sought in each patient using each diagnostic modality. Therapeutic decisions, such as thoracic decompression using chest tube drainage, were left to the discretion of the physician in charge of the trauma patient. A sub-group of severely injured patients was identifi ed as presenting on admission a respiratory and/or cardiovascular sequential organ failure assessment (SOFA) score of 3 or 4. 18

Clinical Examination and Chest Radiography

CE, including bilateral inspection, palpation, percussion, and auscultation for thoracic trauma lesions, was used as tolerated by the in-charge physician, with the patient in the supine position. The presence of subcutaneous emphysema was also noted. CXR was subsequently performed prior to CT scan and interpreted by the same physician (e-Appendix 1). According to the CE and CXR fi ndings, the physician was asked to write in a dedicated patient fi le a diagnosis of each thoracic lesion according to a probability diagnosis scale: 0 5 sure of absence of a lesion, 1 5 doubt the pres-ence of a lesion, 2 5 suspect the presence of a lesion, and 3 5 sure of presence of the lesion.

Thoracic Ultrasonography

Thoracic ultrasonography was performed prior to CT scan using Envisor C (Philips) and an abdominal 5-2 MHz probe

Manuscript received January 26, 2011; revision accepted October 1, 2011 . Affi liations: From the Pôle d’Anesthésie-Réanimation (Drs Hyacinthe, Broux, Francony, Bouzat, Jacquot, Albaladejo, and Payen), and the Département de Radiologie (Dr Ferretti), Hôpital Michallon, et Université Joseph Fourier; and the Centre de Recherche Clinique (Ms Genty and Dr Bosson), INSERM 003, Hôpital Michallon, et TIMC-IMAG, UMR-CNRS 5525, Université Joseph Fourier, Grenoble, France . Funding/Support: The authors have reported to CHEST that no funding was received for this study. Correspondence to: Jean-Francois Payen, MD, PhD, Pôle d’Anesthésie-Réanimation, Hôpital Albert Michallon, BP 217, 38043 Grenoble, France; e-mail: [email protected] © 2012 American College of Chest Physicians. Reproduction of this article is prohibited without written permission from the American College of Chest Physicians ( http://www.chestpubs.org/site/misc/reprints.xhtml ). DOI: 10.1378/chest.11-0208


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(unilateral chest tube placement revealed both a pneumothorax and hemothorax, no CT scan exami-nation), six patients died of refractory intracranial hypertension due to severe head injury, one patient suffered multiple organ failure, and one died of refractory ARDS. Of the 119 patients, 17 patients required thoracic decompression, using 18 chest tubes overall for pneumothorax (n 5 13), hemothorax (n 5 2), or both (n 5 3). Of these, 13 chest tubes were placed before CT scan to drain pneumothorax (eight of 13), hemothorax (two of two), or both (three of three). The period from admission to results for thoracic CT scan was 85 min (65-105 min) with a delay of 60 min (40-85 min) between thoracic ultra-sonography and CT scan.

We found no difference between the right and left chest walls about the occurrence of each thoracic lesion (data not shown), which allowed us to analyze lung fi elds as separate entities. There were 237 lung fi elds analyzed for pneumothorax and hemothorax and 236 for lung contusions. Eighteen lung fi elds had subcutaneous emphysema. There were 53 cases of pneumothoraces (15 lung points), 35 cases of hemothoraces, and 147 cases of lung contusions according to reference methods. Table 2 shows the sensitivity, specifi city, likelihood ratios, and AUC-ROC curves for each diagnostic method. The AUC-ROC of ultrasonography for pneumothorax and lung con-tusion diagnosis was signifi cantly higher than the AUC-ROC curve of CE 1 CXR ( P , .05) ( Fig 3 ). We found no signifi cant difference between the two diagnostic modalities for hemothorax diagnosis ( P 5 .09) ( Fig 3 ).

In a subgroup of 35 patients with a respiratory and/or cardiovascular SOFA score of 3 or 4 on admis-sion, thoracic ultrasonography was the only modality to enhance its diagnostic performance in detecting pneumothorax in these patients by comparison with patients with no cardiovascular failure ( Table 3 ). The AUC-ROC curves of the three operators (A.-C. H., C. B., G. F.) were comparable for the three thoracic lesions (e-Appendix 3).

Of the 25 pneumothoraces not diagnosed on ultra-sonography, 15 corresponded to small pleural air bubbles, eight were not accessible (eg, retrosternal, in the posterior mediastinal region, or beneath a bandage), and two occurred in lung fi elds with subcu-taneous emphysema. Only one pneumothorax was missed on thoracic ultrasonography that subsequently required a chest tube according to the CT scan; in that case, there was a 1-hour delay between thoracic ultrasonography and CT scan in a patient with subcu-taneous emphysema. Of 22 missed hemothoraces, 20 were minimal and located posteriorly and two occurred in lung fi elds with subcutaneous emphy-sema. Only one hemothorax was missed by thoracic

Figure 1. Typical image of pneumothorax. Left, M-mode imag-ing showing the absence of movement of the lung under the pleu-ral line. Right, Conventional two-dimensional imaging of the pleural line (double-headed arrow) and the shadow of two ribs (thick arrow). Note the presence of A-lines (thin arrows) and the absence of B-lines.

Figure 2. Left, Typical image of hemothorax and lung contusion in M-mode. Right, Typical image of hemothorax and lung contu-sion in conventional two-dimensional imaging. Hemothorax (H) is contained between parietal and visceral pleura (white arrows). Lung contusion has irregularly delineated tissue image (black arrows) and air artifact.

Results

Of the 137 consecutive patients screened dur-ing the study period, 18 were excluded from the analysis: 11 patients had CT scans not reviewed by the radiologist, two patients had no indication for a CT scan, and fi ve patients had thoracic ultrasonog-raphy after CT examination or chest tube drainage. Of the 119 included patients, fi ve patients had evi-dence of penetrating thoracic trauma ( Table 1 ). All patients were admitted to the ED within 120 min (90-150 min) of the initial trauma. Nine patients died before discharge from the hospital: One patient suf-fered complete aortic disruption after blunt trauma


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thoracic trauma. Furthermore, the diagnostic perfor-mance of thoracic ultrasonography was enhanced to detect pneumothorax in patients with hemodynamic and/or respiratory instability. Due to its accessibility in the emergency setting, thoracic ultrasonography should be encouraged to markedly enhance the eval-uation of chest trauma patients.

In ICU patients with ARDS, thoracic ultrasonog-raphy detected pleural effusion, alveolar consolida-tion, and interstitial syndrome more accurately than CE or CXR. 21-23 However, the major breakthrough with thoracic ultrasonography came with the early assessment of chest trauma patients, as shown for sion. 16 Adding to these studies with separated dis-orders, we deliberately chose to evaluate the accu-racy of thoracic ultrasonography in consecutive trauma patients in the ED.

We found that the sensitivity of thoracic ultraso-nography in detecting each thoracic lesion ranged from 37% to 61%. This is much lower than the 85% to 100% sensitivities reported from earlier stud-ies. 17 There are several explanations for these dis-crepancies. Patients with other thoracic lesions than assessed, those with subcutaneous emphysema, or

Table 2— Sensitivity, Specifi city, Positive and Negative Likelihood Ratios, and AUC-ROC of CE 1 CXR

vs Thoracic Ultrasonography for Detecting Pneumothorax, Hemothorax, and Lung Contusion

in 119 Patients With Thoracic Trauma

Findings CE 1 CXRThoracic

Ultrasonography

Pneumothorax (n 5 53) Sensitivity, % 19 53 Specifi city, % 100 95 Positive likelihood / 9.7 Negative likelihood 0.8 0.5 Correctly classifi ed, % 82 85 AUC-ROC, mean, 95% CI 0.62 (0.54-0.70) 0.75 (0.67-0.83)Hemothorax (n 5 35) Sensitivity, % 17 37 Specifi city, % 94 96 Positive likelihood 2.9 9.4 Negative likelihood 0.9 0.7 Correctly classifi ed, % 83 87 AUC-ROC, mean, 95% CI 0.59 (0.50-0.69) 0.69 (0.60-0.78)Lung contusion (n 5 147) Sensitivity, % 29 61 Specifi city, % 94 80 Positive likelihood 5.2 3 Negative likelihood 0.7 0.5 Correctly classifi ed, % 54 68 AUC-ROC, mean, 95% CI 0.66 (0.61-0.72) 0.74 (0.67-0.80)

Two hundred thirty-seven lung fi elds were assessed for pneumotho-rax and hemothorax and 236 lung fi elds for lung contusion. The accuracy of each diagnostic modality was assessed using a probabil-ity diagnosis scale score of 2 or 3 (see text). / 5 impossible to calcu-late because the specifi city was 100%; AUC-ROC 5 area under the receiver operating characteristic curve; CE 5 clinical examination; CXR 5 chest radiograph.

Table 1— Baseline Characteristics and Physiologic Data Collected on Admission From 119 Patients

With Thoracic Trauma

Characteristics Patients

Age, y 39 (22-51)Male sex 97 (82)BMI 24 (22-26)Injury type Motor accident 51 (43) Sports-related 25 (21) Fall 37 (31) Other 6 (5)ISS 17 (9-29)SAPS II 25 (13-45)SOFA score 3 or 4 on admission a 35 (29) Respiratory 15 (13) Cardiovascular 30 (25)Thorax-AIS b 2 (0-3)In-hospital mortality 9 (8)Heart rate, bpm 89 (75-100)SABP, mm Hg 130 (110-142)Catecholamines 31 (26)Sa o 2 on admission, % 100 (98-100)MV 62 (52)For patients with MV Pa o 2 , mm Hg 240 (150-370) Pa co 2 , mm Hg 35 (31-40) Arterial pH 7.35 (7.27-7.39)Head trauma 79 (66)GCS score 14 (7-15)

Data are expressed as medians (IQR) or No. (%). AIS 5 Abbreviated Injury Scale; GCS 5 Glasgow Coma Scale; IQR 5 interquartile range; ISS 5 Injury Severity Score; MV 5 mechanical ventilation; SABP 5 sys-tolic arterial BP; Sa o 2 5 arterial oxygen saturation; SAPS II 5 Simpli-fi ed Acute Physiology Score II; SOFA 5 Sequential Organ Failure Assessment. a The number of individual organ failures (SOFA score 3 or 4) exceeds the total number of included patients. b The maximum thorax AIS score (thorax-AIS) ranges from 1 to 6; severe thoracic damage is given an AIS score of 3 or more, and no thoracic lesion is 0.

ultrasonography that subsequently required a chest tube according to the CT scan; in that case, the chest tube was initially placed to drain an anterior pneu-mothorax in a lung fi eld with subcutaneous emphy-sema. Of the 57 undiagnosed lung contusions, 35 were minimal and/or posterior, 13 were not acces-sible to ultrasound (eg, retrosternal or paravertebral), and two lung contusions occurred in lung fi elds with substantial subcutaneous emphysema. Seven lung contusions were missed by thoracic ultrasonography for reasons that remain unclear.

Discussion

This cohort study showed thoracic ultrasonog-raphy as superior to the combined CE and CXR in diagnosing pneumothorax and lung contusion in trauma patients seen in the ED with a suspicion of



secured onto a vacuum mattress for spinal immobi-lization. This limitation explains why ultrasonog-raphy showed modest value for hemothorax, and why the rate of lung point was weak (15 of 53).

Despite relatively unfavorable conditions to assess its performance, thoracic ultrasonography showed higher accuracy than combined CE and CXR in the detection of pneumothorax and lung contusions. We determined the receiver operating characteristic curves of these two diagnostic modalities that revealed how accurate each modality was at detecting or rul-ing out various thoracic lesions. 24 We constructed a probability diagnosis scale refl ecting doubts and certainties about the interpretation of results from each diagnosis modality, as seen in clinical practice, and a score of 2 or 3 was considered as refl ecting the operator’s conviction about the presence of thoracic lesion. The 95% CI lower limit of the area under the curve for CE 1 CXR was close to 0.5 for the diag-nosis of the three thoracic lesions, confi rming their low selectivity in chest trauma patients. However, the diagnostic accuracy of thoracic ultrasonography did not differ statistically from that of CE and CXR

those who required mechanical ventilation were excluded from some former studies. 11,12,15,16 In this study, the presence of pneumothorax or hemotho-rax could have prevented the diagnosis of underlying disease such as lung contusion, as previously shown. 10 In the two missed pleural effusions that subse-quently required a chest tube according to the CT scan, the lung fi eld had substantial subcutaneous emphysema, a condition known to impair the explo-ration of parietal pleura by thoracic ultrasonography. The 1-hour delay between thoracic ultrasonography and CT scan might have allowed a thoracic lesion undetectable at the time of ultrasonography to pro-gress to become recognizable on CT scan. Moreover, the diagnostic performance of thoracic ultrasound diagnosis was assessed with a physician blinded to the CE and CXR results. It is unlikely but not fully ruled out that knowledge of the patient’s condition during the thoracic ultrasound examination had infl uenced the rate of probability diagnosis scale. Above all, the exploration by thoracic ultrasonography was limited to the anterior and axillary areas because, in our insti-tution, all trauma patients admitted to the ED are

Figure 3. Receiver operating characteristic curves of CE 1 CXR vs thoracic US in diagnosing pneumothorax, hemothorax, and lung contusion in 119 patients with thoracic trauma. A, Pneumothorax. B, Hemothorax. C, Lung contusion. Thoracic CT scan (or chest drain if placed prior to the CT scan) was used as the reference diagnostic method. CE 5 clinical examination; CXR 5 chest radiography; US 5 ultrasonography.

Table 3— Comparison of the AUC-ROC of CE 1 CXR and Thoracic Ultrasonography for Detecting Pneumothorax, Hemothorax, and Lung Contusion, According to the Presence of a Respiratory and/or CV Failure on Admission

Findings Lung Fields in Patients With SOFA 3-4 (n 5 69) Lung Fields in Patients With SOFA 0-2 (n 5 168) P Value

Pneumothorax (n 5 53) CE 1 CXR 0.65 (0.51-0.79) 0.61 (0.51-0.71) .62 Ultrasonography 0.86 (0.73-0.98) 0.70 (0.61-0.80) .05Hemothorax (n 5 35) CE 1 CXR 0.45 (0.32-0.59) 0.67 (0.56-0.79) .02 Ultrasonography 0.66 (0.51-0.81) 0.70 (0.59-0.81) .67Lung contusion (n 5 147) CE 1 CXR 0.71 (0.62-0.80) 0.65 (0.58-0.72) .32 Ultrasonography 0.74 (0.62-0.87) 0.73 (0.66-0.81) .84

Data are presented as mean (95% CI). Respiratory and CV failure defi ned by a SOFA score of 3 or 4 (n 5 35 chest trauma patients). CV 5 cardiovascular. See Table 1 and 2 legends for expansion of other abbreviations.


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Dr Payen: contributed to designing the research, analyzing data, and writing the manuscript. Financial/nonfi nancial disclosures: The authors have reported to CHEST that no potential confl icts of interest exist with any companies/organizations whose products or services may be dis-cussed in this article . Additional information: The e-Appendixes can be found in the Online Supplement at http://chestjournal.chestpubs.org/content/141/5/1177/suppl/DC1.

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for hemothorax diagnosis, in line with previous studies. 14,15 This lack of difference in our study could be due to the supine position of patients, preventing an adequate examination of posterior lung regions. Nevertheless, the diagnostic accuracy of thoracic ultra-sonography was enhanced to detect pneumothorax in patients with hemodynamic and/or respiratory insta-bility. No such effect was found with CE 1 CXR. These fi ndings might provide important insights into the value of thoracic ultrasonography in the prompt assess-ment of this subgroup of patients.

This study is observational. Whether the diagnosis ascertained by thoracic ultrasonography infl uences the decision-making process also needs to be evalu-ated. In addition, it is believed that ultrasonog-raphy is an operator-dependent examination. We did not test its reproducibility among our operators by using a k -test. However, the absence of a signifi cant difference in diagnostic performance between our three operators argues against a substantial operator performance bias, because they probably used stan-dardized signs. This study considered physical exam-ination plus radiography as a whole. Consequently, the value of each cannot be assessed separately. Data extracted from physical examination sometimes have considerable value (eg, in patients with massive pneu-mothorax and no sonographic lung point). In any case, clinical examination should be still carried on.

In conclusion, thoracic ultrasonography is more accurate than clinical examination and bedside CXR in comparison with CT scanning when evaluating supine chest trauma patients. Early diagnosis of pneu-mothorax and lung contusion can be made using this modality. Because of its availability at the bedside, thoracic ultrasonography should be considered in the initial evaluation of chest trauma patients in the emergency setting.

Acknowledgments Author contributions: Dr Payen is the guarantor of the manu-script, taking responsibility for the integrity of the work as a whole, from inception to published article . Dr Hyacinthe: contributed to performing research, analyzing data, and writing the manuscript. Dr Broux: contributed to designing and performing research, analyzing data, and writing the manuscript. Dr Francony: contributed to performing research and drafting, revising, and approving the manuscript. Ms Genty: contributed to analyzing data and revising the manu-script. Dr Bouzat: contributed to performing research and reviewing the manuscript. Dr Jacquot: contributed to analyzing data and reviewing and approving the manuscript. Dr Albaladejo: contributed to analyzing data and reviewing and approving the manuscript. Dr Ferretti: contributed to performing research and revising and approving the manuscript. Dr Bosson: contributed to designing the research, analyzing data, and revising and approving the manuscript.


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17 . Wilkerson RG , Stone MB . Sensitivity of bedside ultrasound and supine anteroposterior chest radiographs for the iden-tifi cation of pneumothorax after blunt trauma . Acad Emerg Med . 2010 ; 17 ( 1 ): 11 - 17 .

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21 . Lichtenstein D , Goldstein I , Mourgeon E , Cluzel P , Grenier P , Rouby JJ . Comparative diagnostic performances of auscul-tation, chest radiography, and lung ultrasonography in acute respiratory distress syndrome . Anesthesiology . 2004 ; 100 ( 1 ): 9 - 15 .

22 . Remérand F , Dellamonica J , Mao Z , et al . Multiplane ultra-sound approach to quantify pleural effusion at the bedside . Intensive Care Med . 2010 ; 36 ( 4 ): 656 - 664 .

23 . Rocco M , Carbone I , Morelli A , et al . Diagnostic accuracy of bedside ultrasonography in the ICU: feasibility of detect-ing pulmonary effusion and lung contusion in patients on respiratory support after severe blunt thoracic trauma . Acta Anaesthesiol Scand . 2008 ; 52 ( 6 ): 776 - 784 .

24 . Hanley JA , McNeil BJ . The meaning and use of the area under a receiver operating characteristic (ROC) curve . Radiology . 1982 ; 143 ( 1 ): 29 - 36 .


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Diagnostic Accuracy of Ultrasonography in the Acute Assessment of Common Thoracic Lesions After Trauma