The study objective was to determine the usefulness of routine early (within 24 h after admission) and late (on the 3rd posttraumatic day) flexible fiberoptic bronchoscopy in patients with severe chest trauma. METHODS By history, physical examination, and radiologic findings, we identified 15 consecutive patients, all of whom were anaesthetized, orally intubated, and mechanically ventilated. There was no change in ventilation, including FIO2, for bronchoscopy. The patients had continuous cardiovascular monitoring and peripheral pulse oximetry. The bronchoscope was inserted through a tight-fitting side port at the endotracheal tube connector. Pulse rate, mean arterial pressure, and arterial blood gases were recorded before, 1 min after, and 10 min after bronchoscopy, as were intracranial pressure (ICP) in 7 patients with an ICP probe (early bronchoscopy only) and the duration of the examination. Statistical significance was tested by means of the Wilcoxon test for correlating samples. Significance was assumed at P less than 0.05 in a two-sided test. RESULTS Early bronchoscopy revealed two bronchial avulsions, two aspirations, and ruled out one suspected aspiration. Late bronchoscopy showed plugging of at least 3 segmental bronchi by clots in 4 patients, none of whom was able to expectorate effectively. In general, changes in the observed vital parameters were minimal. There was a significant but clinically irrelevant increase in mean pulse rate before and 1 min after early bronchoscopy. CONCLUSIONS We conclude that bronchoscopy should always be considered in patients with severe chest trauma, the decision being based on typical radiological findings as well as clinical signs and symptoms. Given the proper indication, bronchoscopy supplies valuable information at minimal risk to the patient.