Touw HR, et al. - In this prospective, observational, single-centre study in a tertiary intensive care unit, researchers compared the diagnostic accuracy of lung ultrasound with that of chest X-ray to detect postoperative pulmonary complications in adult patients who had undergone cardiothoracic surgery. Lung ultrasound facilitated bedside decision making and showed utility in detecting postoperative pulmonary complications and hence may be used as the primary imaging technique for this purpose in such a patient populace.

Methods

• On admission and on postoperative days 2 and 3, chest X-ray findings were recorded in addition to rates of postoperative pulmonary complications and clinically-relevant postoperative pulmonary complications that required therapy according to the treating physician as part of their standard clinical practice.
• An independent researcher performed lung ultrasound at the time of chest X-ray.
• Comparisons between lung ultrasound and chest X-ray were carried out with respect to the detection of postoperative pulmonary complications and clinically-relevant postoperative pulmonary complications.
• Inter-observer agreement for lung ultrasound as well as the time to perform both imaging techniques was evaluated.
• Using subgroup analyses, the time to detection of clinically-relevant postoperative pulmonary complications by both modalities was compared.

Results

• Data showed a total of 177 patients underwent both lung ultrasound and chest X-ray imaging.
• Lung ultrasound vs chest X-ray identified 159 (90%) vs 107 (61%) postoperative pulmonary complications on the day of admission, respectively (p < 0.001).
• The presence of clinically-relevant postoperative pulmonary complications was detected by lung ultrasound in 11 out of 17 patients (65%) and by chest X-ray in 7 out of 17 patients (41%) (p < 0.001).
• Lung ultrasound vs chest X-ray (p=0.024) provided earlier detection of clinically-relevant postoperative pulmonary complications.
• Excellent inter-observer agreement was observed for lung ultrasound (κ = 0.907, p < 0.001).
• Lung ultrasound vs chest X-ray detected more postoperative pulmonary complications and clinically-relevant postoperative pulmonary complications after cardiothoracic surgery, and at an earlier time-point.