Chest radiographs in 104 French ICUs: current prescription strategies and clinical value (the RadioDay study).

Objective: To analyze the current practices of chest radiograph (CXR) prescription and their clinical impact.
Design: Prospective snapshot observational study (on RadioDay) combined with a survey.
Patients: Patients who were given a CXR on RadioDay.
Setting: One hundred four French intensive care units (ICUs).
Results: On RadioDay, 854 CXRs (in 804 patients) were ordered. For the "CXRs morning round," the prescription policy was declared to be "on-demand" (in 63 % of the ICUs), "daily routine only in mechanically ventilated patients (MV)" (30 %) or, less frequently, "daily routine in all patients" (7 %). When analyzing the two main local policies, as compared with "daily routine only in MV" ICUs, in "on-demand" ICUs: (1) fewer CXRs were ordered (0.6 ± 0.3 vs. 0.9 ± 0.2 CXRs/patient, p < 0.001) with no increase in the rate of unscheduled CXRs (i.e., CXRs performed outside the morning round), and (2) individual CXRs were more often followed by a therapeutic intervention (which would not have occurred without the CXR): 34 vs. 25 % of the CXRs (p < 0.05). Last, in case of severe respiratory disease (low PaO(2)/FiO(2) ratio), it is noteworthy that the clinical value of "on-demand" individual CXRs was still markedly higher than that of "daily routine" CXRs.
Conclusion: Nearly two-thirds of the participating ICUs adopted the "on-demand" strategy of prescription, which was associated with a lower rate of CXRs with no increase in unscheduled CXRs and was of higher clinical value than a "daily routine in MV" strategy. Importantly, the study design did not allow assessing if the "on-demand" strategy had missed or delayed some diagnoses.