P ulmonary torsion is an uncommon complication of trauma or thoracic operations. 1,2 Increasing surgeon awareness about its existence is important because pulmonary torsion bears significant mortality, which may be decreased if recognized early and treated expeditiously. 1 Pathognomonic radiographic findings exist. 3,4 Spontaneous, pulmonary torsion is a very rare entity with poorly understood etiology. 5,6 In the absence of pulmonary resection, the etiology of pulmonary torsion is unclear and only speculative. We report a case of partial pulmonary torsion in the absence of pulmonary resection, aiming to elucidate the underlying mechanisms leading to its development and the differences with complete torsion.A 22-year-old male was brought in by paramedics, following a single transmediastinal gunshot wound. On arrival to the emergency room, his blood pressure was 132/82 mm Hg, pulse rate 100 beats/min, and hematocrit 32%. A left thoracostomy tube immediately drained 1400 mL of blood, prompting transfer to the operating room. Following singlelumen endotracheal intubation, a left anterior thoracotomy revealed a through-and-through laceration at the left upper lung and transection of the left internal mammary artery. The bullet entered the antero-medial portion of the upper lobe (Segment 1), exiting to the antero-lateral portion of the same lobe (Segment 2) after an approximately 10 cm course through the lung. The trajectory was not close to the pulmonary hilum and involvement of major pulmonary vessels did not exist. The oblique fissure was incomplete. A rudimentary pulmonary ligament was noted. The internal mammary artery was ligated. The bullet trajectory was unroofed by stapled tractotomy and individual suture ligation controlled bleeding vessels and sites of air leak. Because of our experience with a previous case of pulmonary torsion, 3 we paid particular attention at the end of the operation to expand the repaired lung and place it in its correct anatomic position. A posterior thoracostomy tube was placed and the thoracic wall closed, per standard fashion.Postoperatively, the patient remained on mechanical ventilatory support. On the first postoperative day, he did well with a partial arterial oxygen tension to fractional inspired oxygen ratio of 400. There was minimal drainage from the thoracostomy tube. However, the chest radiograph showed opacification of the entire left lung with mild mediastinal shift to the right (Fig. 1). Pulmonary torsion was immediately suspected; however, bronchoscopy revealed a tight, but patent left main stem bronchus. The upper and lower lobe bronchi were also intubated with some difficulty. The bronchoscopy was repeated 4 hours later by an experienced intensivist. Findings were unchanged, but the patient's respiratory status began to deteriorate. Still maintaining a high index of suspicion for pulmonary torsion, we ordered a helical computed tomography (CT) of the chest, which was done approximately 24 hours after the operation. It showed a nonvascularized, sub-aerated, engorged l...
