B80-6-01 Lung Torsion of the Right Middle Lobe After Robotic Assisted Right Lower Lobectomy

Abstract Introduction Lobar torsion is characterized by a malrotation of the lobes of the lung resulting in life-threatening compromise of the airway and pulmonary vasculature. This complication is exceedingly rare, with incidence reported as low as 0.089%. It can occur because of trauma or as a result of surgical intervention to the thorax, be it lobectomy, thoracotomy, or lung transplant. Surgical techniques such as pneumopexy or pleurodesis may be used to avoid torsion post-operatively, but do not guarantee prevention. Description A 75-year-old male was found to have a 2.0 x 1.1 cm right lower lobe lung nodule on screening CT. Navigational bronchoscopy was positive for mucinous adenocarcinoma. PET scan was negative for metastatic or regional disease; thus, the patient was referred for robotic right lower lobectomy. During the primary operation, dissection around the lower lobe pulmonary artery was noted to be difficult and the operation was converted to an open thoracotomy. Once the right lower lobe (RLL) was resected, the right upper (RUL) and right middle (RML) lobes were noted to expand nicely. Three sutures were placed to approximate the RML to the RUL edges, to prevent torsion of the RML. On post-operative day 4, some resistance was noted during the attempted removal of the apical chest tube, which prompted CT evaluation. This revealed an opacification of the RML- a concern for possible lobar torsion of RML. The patient returned to the operating room for exploratory thoracotomy. They attempted to pass a 5.8 bronchoscope into a constricted RML bronchus, then attempted a 3.5 bronchoscope, which was advanced with difficulty, likely due to compression by the neighboring anatomy. This further highlighted the concern for compression or torsion of the lobe. Upon examination, the RML appeared boggy, congested and failed to expand; it was resected to prevent further complications. The pathology report described sites of normal lung surrounded by signs of intraparenchymal hemorrhage and early necrosis consistent with the vascular compromise, as seen in lobar torsion. Discussion Middle Lobe Torsion (MLT) is the rotation of the lobe leading to obstruction of the bronchovascular pedicle. MLT is rare following upper lobe resection and even rarer following lower lobe resection. Mechanical alterations in the vasculature lead to ischemia and vascular congestion with subsequent pulmonary capillary hemorrhage, and erythrocytes infiltration into the airway leading to necrosis of the lobe and loss of viability. Early identification and surgical detorsion should be pursued to avoid lobectomy. This abstract is funded by: None