MedPage Today -- Chest radiographs for mechanically ventilated patients that are taken as needed, rather than as part of daily routine, reduce radiation exposure without compromising safety, researchers found. An on-demand approach reduced chest x-rays by 32% for these ICU patients (mean 0.75 versus 1.09 radiographs per-patient day of ventilation, P<0.0001), in a randomized clinical trial led by Gilles Hejblum, PhD, of the Institut National de la Santé et de la Recherche Médicale in Paris.