Chest sonography: a useful tool to differentiate acute cardiogenic pulmonary edema from acute respiratory distress syndrome.
BACKGROUND
Differential diagnosis between acute cardiogenic pulmonary edema (APE) and acute lung injury/acute respiratory distress syndrome (ALI/ARDS) may often be difficult. We evaluated the ability of chest sonography in the identification of characteristic pleuropulmonary signs useful in the diagnosis of ALI/ARDS and APE.


METHODS
Chest sonography was performed on admission to the intensive care unit in 58 consecutive patients affected by ALI/ARDS or by acute pulmonary edema (APE).


RESULTS
Ultrasound examination was focalised on finding in the two groups the presence of: 1) alveolar-interstitial syndrome (AIS) 2) pleural lines abnormalities 3) absence or reduction of "gliding" sign 4) "spared areas" 5) consolidations 6) pleural effusion 7) "lung pulse".AIS was found in 100% of patients with ALI/ARDS and in 100% of patients with APE (p = ns). Pleural line abnormalities were observed in 100% of patients with ALI/ARDS and in 25% of patients with APE (p < 0.0001). Absence or reduction of the 'gliding sign' was observed in 100% of patients with ALI/ARDS and in 0% of patients with APE. 'Spared areas' were observed in 100% of patients with ALI/ARDS and in 0% of patients with APE (p < 0.0001). Consolidations were present in 83.3% of patients with ALI/ARDS in 0% of patients with APE (p < 0.0001). A pleural effusion was present in 66.6% of patients with ALI/ARDS and in 95% of patients with APE (p < 0.004). 'Lung pulse' was observed in 50% of patients with ALI/ARDS and in 0% of patients with APE (p < 0.0001). All signs, except the presence of AIS, presented a statistically significant difference in presentation between the two syndromes resulting specific for the ultrasonographic characterization of ALI/ARDS.


CONCLUSIONS
Pleuroparenchimal patterns in ALI/ARDS do find a characterization through ultrasonographic lung scan. In the critically ill the ultrasound demonstration of a dyshomogeneous AIS with spared areas, pleural line modifications and lung consolidations is strongly predictive, in an early phase, of non-cardiogenic pulmonary edema.
Copetti
Roberto
R
Emergency Department S, Antonio Abate General Hospital, Tolmezzo, Italy. robcopet@tin.it
Soldati
Gino
G
Copetti
Paolo
P
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003937:Diagnosis, Differential; D006801:Humans; D008875:Middle Aged; D011654:Pulmonary Edema / Q000000981:diagnostic imaging* / Q000209:etiology*; D015203:Reproducibility of Results; D012128:Respiratory Distress Syndrome / Q000000981:diagnostic imaging*; D012680:Sensitivity and Specificity; D012770:Shock, Cardiogenic / Q000150:complications* / Q000000981:diagnostic imaging*; D013909:Thorax / Q000000981:diagnostic imaging*; D014463:Ultrasonography / Q000379:methods*