Pulmonary complications of the McSwain Dart.

We evaluated the McSwain Dart on a "worst case" basis. Dogs were sedated with 30 mg/kg pentobarbital, intubated, and placed on 15 cm H2O positive end-expiratory pressure. Percutaneous introduction of the McSwain Dart was not possible without parenchymal damage to the lung in over 20 attempts under these conditions. The McSwain Dart should be used only when the diagnosis of pneumothorax is without doubt.