The efficacy of sighs in patients with COPD undergoing general anesthesia and controlled ventilation.

Fourteen patients with COPD underwent elective procedures below the umbilicus, all receiving a standard anesthetic. They were randomized to one of four groups differentiated by the presence or absence of sighing during mechanical ventilation. Patients who were sighed experienced both statistically and clinically significant improvement in their oxygenation efficiency as measured by the alveolar to arterial oxygen gradient.