The accuracy and efficacy of portable chest radiography depends largely on the techniques used at the bedside and more importantly on the consistency with which these techniques are used. Routine chest exams are obtained in the radiology department in a posteroanterior (PA) direction to minimize magnification of the heart. The optimal ICU chest radiograph is obtained in the anteroposterior (AP) view at a target-to-film distance of 72 inches with the patient in the upright position at maximum inspiration; alternatively a distance of 40 inches is used in the supine patient. Due to the decreased mobility of patients in the ICU, chest radiographs are often taken while the patient is supine.

A normal anteroposterior chest radiograph