Pulmonary function studies after smoke inhalation

Pulmonary function studies were performed within 72 hours of injury in seven patients with smoke inhalation injury diagnosed by positive ¹³³Xe scintiphotographs and in eight patients with burns of similar size but with negative ¹³³Xenon scans. The former patients showed decreased peak flow, decreased flow at 25, 50, and 75 per cent of vital capacity, and an elevated pulmonary resistance. In addition, single breath nitrogen tests revealed evidence of maldistribution of ventilation/perfusion abnormalities. Total lung capacity, functional residual capacity, and compliance (both dynamic and static) were similar in the two groups. Pulmonary function studies can be of assistance in evaluating smoke inhalation, estimating the severity, and following the course of patients with this disorder.