The risk of pulmonary infectious complications in critically ill patients requiring ventilatory support is well established. To evaluate the impact of tracheal intubation on the risk of pneumonia, the records of three hundred seventy thermally injured patients (mean age, 37.6 years, mean total body surface area burn, 44.7%) who were admitted during a 6-year interval and required ventilatory support were reviewed. The mean duration of intubation in these patients was 16.6 days, the incidence of pneumonia was 50%, and observed mortality was 37% (137 patients). Though they were significantly older (42.7 vs 35.6 years, p = 0.005) and had a higher frequency of pneumonia (60% vs 46%, p = 0.015) than the 265 patients with inhalation injury, the 105 patients without documented inhalation injury had mean burn size (41.9% vs 45.9%), length of intubation (18.9 vs 15.7 days), postburn day of pneumonia (12.7 vs 10.5 days), and mortality (38.1% vs 36.6%) similar to that group. Actuarial Ufe table analysis considering only pneumonia acquired during ventilatory support was used to evaluate the relation between the risk of pneumonia and duration of ventilatory support. In this cohort of patients with burns, no difference in the risk of pneumonia was observed between patients with and without inhalation injury who required ventilatory support; the hazard of pneumonia was relatively constant during the first 6 weeks of intubation and was similar for all who underwent ventilation. © 1995, Burn Science Publishers, Inc. All rights reserved.