The pre-operative chest X-ray

"a regular course or procedure, a more or less mechanical or unvarying performance of certain acts or duties". Over tie past 20 years a chest radio-graph has become a routine part of the assessment of a patient prior to general anaesthesia. It is right that we should periodically confirm, or perhaps question, our reasons for performing any investiga-tion which has become routine, particularly when there is some hazard, however small, to the patient as a result of the examination. One must weigh the benefits against the risks. Obviously the benefits are going to be greater in preoperative chest radio-graphy in patients with symptoms or physical signs referable to the chest, than in patients with no chest symptoms. Patients with no chest symptoms or physical signs. There are two reasons for the routine chest radio-graph in this group: (1) to reveal unsuspected disease; (2) as a baseline for postoperative care. Preoperative chest radiography provides an oppor-tunity to screen the population for chest disease. In this country though, it is doubtful whether random radiography of all persons is now justified. The use of mass radiography was widely introduced in the 1940s. Its success in the detection of pulmonary tuberculosis led to the view that every person, whether healthy or not, should have a chest X-ray at least once a year. This training, both of doctors and of the population, is difficult to dispel. In the 1940s 6.7 new cases of pulmonary tuberculosis were being discovered per 1,000 persons X-rayed (Springett and Eley, 1956). Nowadays, figures of 4.4 to 40.5 per 1,000 X-rays are found in develop-ing countries, whereas in industrial countries such as Great Britain, only 0.2 to 4.4 unknown cases of active pulmonary tuberculosis are discovered per 1,000 X-rays (Neumann, 1972). As a result, the use of random mass miniature X-ray surveys of the population has now been greatly reduced. In South-West London in 1972, the incidence of pulmonary tuberculosis in the general public attending the mas