Conventional radiographic studies of the chest in the intensive care unit often fail to positively identify suspected intrathoracic pathology due to many patient- and equipment-related variables. Our experience has indicated that CT scanning of the chest improves diagnostic accuracy, precisely defines anatomic abnormalities, frequently affects treatment decisions, and has been performed safely in this fragile patient population. Examples of correctable lesions have included pneumothorax, empyema, lung abscess, mediastinal abscess and pleural effusion. Chest CT findings always occurred while the portable plane chest radiographs were nondiagnostic. CT-directed intervention often improved patient outcome.