[Agreement between lung ultrasonography and chest radiography in the intensive care unit]

Because the chest radiograph currently remains the routine choice of imaging for the examination of the chest in the intensive care unit, we compared lung ultrasonography with chest radiography.

Observational prospective study.

An ultrasound examination and chest radiography were simultaneously ordered in 50 patients whose clinical exam justified a lung exploration. Each exam was interpreted independently by an intensivist. The abnormalities found were classified into interstitial syndrome, alveolar consolidation, and pleural effusion. An agreement analysis was performed between the results of the two techniques. The delay between the order and interpretation of both investigations, and the degree of interobserver agreement were also collected.

The kappa agreement between lung ultrasonography and chest radiography was 0.42. In total, 329 total abnormalities were detected, 156 abnormalities were found by both techniques, 31 by radiography alone, and 142 by ultrasonography alone. The interobserver agreement was 0.86. Ultrasonography was performed with a shorter delay (14.8 ± 6.9 min vs 44.2 ± 21.4 min).

There was only moderate agreement between lung ultrasonography and chest radiography for the diagnosis of interstitial syndrome, alveolar consolidation and pleural effusion in intensive care unit. This result is mainly explained by the higher number of ultrasound abnormalities. With the ability to provide fast diagnosis, good reproducibility and high feasibility, ultrasound scan could represent an alternative exam for chest exploration in intensive care unit.