The value of daily routine chest radiographs in intensive care patients

Introduction

It is uncertain whether daily routine chest radiographs (CXRs) truly affect the daily management of critically ill patients. The consensus opinion of the American College of Radiology, however, is that routine CXRs are indicated in all mechanically ventilated patients http://www.acr.org.

Methods

The study was performed in a mixed surgical/medical ICU. During a period of 6 months, routine CXRs were performed next to CXRs on clinical indication (on-demand CXRs). During a second phase of 3.5 months, the routine CXR was abandoned and only on-demand CXRs were made. Questionnaires (on the back side of each CXR request form) were completed for all CXRs, addressing the indication and expected findings. The presence of the following abnormalities was scored by the radiologist: pulmonary abnormalities (atelectasis, major infiltrates, any pneumothorax, pulmonary congestion or significant pleural fluid), and abnormal position of any invasive device (tube, central venous lines). Statistical analysis was by chi-squared test.

Results

During the first 6 months, 5180 CXRs were made in 888 patients (3400 routine and 1780 on-demand CXRs). Of all routine CXRs, only 221 revealed an unexpected abnormality (6.5%) compared with 249 of the on-demand CXRs (14.0%) (χ² = 79.42, df = 1, P < 0.0001). These findings included (on the routine CXRs) 1.2% malposition of the tube, 1.1% malposition of central venous lines and 1.2% atelectasis, versus 1.8% malposition of the tube, 1.8% malposition of central venous lines and 1.2% atelectasis in the on-demand CXRs. In the second period, 1093 (all 'by definition' on-demand) CXRs were made in 425 patients. Of these CXRs, 153 revealed an 'unexpected' abnormality (14.3%) (χ² < 0.0001, df = 1, P = not significant); these findings included 2.2% malposition of the tube, 2.7% malposition in central venous lines and 2.8% pleural fluid.

Conclusion

Compared with the first period, the number of on-demand CXRs did not change in the second period. In addition, the incidence and type of unexpected findings of on-demand CXRs did not change. From this we can conclude that daily routine CXRs may not be necessary for all ICU patients.