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Lung torsion is a rare but life-threatening condition in which rotation of the lung or a pulmonary lobe causes bronchovascular compromise, airway obstruction, and, if untreated, irreversible necrosis. Most commonly occurring after thoracic surgical procedures, trauma, or lung transplant, lung torsion carries a mortality rate as high as 8.3% and is misdiagnosed in nearly 1 in 5 affected patients. Despite the availability of diagnostic imaging modalities and bronchoscopy, clinicians across specialties frequently lack the knowledge needed to promptly recognize and manage this condition. This activity provides a comprehensive review of the etiology, pathophysiology, clinical presentation, diagnostic evaluation, and surgical management of lung torsion. Participants gain actionable skills to improve diagnostic accuracy, implement timely intervention, prevent complications, and coordinate effective interprofessional communication to optimize patient outcomes. Objectives: Identify the common and spontaneous causes of lung torsion in both adult and pediatric patients, including thoracic surgical procedures, trauma, and lung transplant. Assess the urgency of surgical intervention in patients with suspected lung torsion based on the degree of bronchovascular compromise, the time since onset, and the viability of the affected lung tissue. Implement prophylactic measures following thoracic surgical procedures, including pneumopexy and intravenous heparin infusion, to reduce the risk of lung torsion and associated thromboembolic complications. Collaborate with thoracic surgeons, radiologists, nurses, and surgical assistants to ensure rapid interprofessional communication, timely diagnosis, and coordinated surgical correction of lung torsion in the emergent setting. Access free multiple choice questions on this topic.

Lung torsion is a rare condition that is classically seen when a disruption occurs in the thoracic cavity. Common causes of lung torsion include thoracotomy, lung transplant, and trauma. However, spontaneous cases have also been reported.[1]Lung torsion is a life-threatening condition that requires timely diagnosis because lung rotation can cause vascular compromise and airway obstruction, resulting in lung tissue necrosis. With immediate management, the affected lung or pulmonary lobe can be salvaged. Overall, lung torsion has a poor prognosis when misdiagnosis or treatment delay occurs. If detorsion occurs and the lung is fixed in place, the lung can recover full function. This article reviews the etiology, epidemiology, clinical manifestations, diagnosis, and management of lung torsion.

A history of intrathoracic procedures is common in patients with lung torsion, although spontaneous etiologies are also known.[1] The causes of lung torsion in adults include the following: Thoracic or abdominal trauma [2] Lung transplant [3][4] Unilateral Bilateral Video-assisted thoracoscopic surgery procedure [5] Thoracentesis [6] Thoracic procedures [7] Transesophageal operation [8] Aorta repair [9] Transthoracic correction of hiatal hernia [10] Transthoracic needle aspiration Transabdominal surgical diaphragmatic hernia Spontaneous etiology Pneumothorax [1] Pleural effusion Lobar atelectasis [11] Pulmonary sequestration [12] Diaphragmatic hernia [8] Commonly known causes of lung torsion in pediatric patients include the following: Blunt thoracic and abdominal trauma [12] Tracheoesophageal repair [13] Thoracotomy for hiatal hernia [14] Ductus arteriosus closure [15]

Lung torsion is rare, with a reported incidence ranging from 0.089% to 0.3% in a single case series.[16] Results from this case series showed lung torsion in 62.4% of patients postoperatively, 8.3% after trauma, and spontaneously in 29.4% of patients.[16] Additionally, results from the case series showed that 21.6% of lung torsion cases occurred after a VATS procedure and 78.4% after thoracotomy. The case series also reviewed the most commonly involved site of lung torsion. In the series, 74.4% of lung torsions occurred after right upper-lobe lobectomy. The right middle lobe was the most common site overall (29.4% of patients after thoracic surgical procedures). The incidence among sexes was not significantly different. Results from the case series showed that 58.3% of lung torsion cases occurred in men and 41.7% in women.[16]

Lung torsion is a result of a disruption in the thoracic cavity and commonly occurs following upper lobectomy.[16] The disruption can range from thoracotomy to pleural effusion, pneumothorax, trauma, or anything that can affect the vasculature or lung tissue. Fluid accumulation from pleural effusion, inflammatory infiltrates from atelectasis, opacities from pneumonia, or other invasive procedures can compress the lung, vasculature, or airways. Compression may cause the lung to rotate, obstructing the pulmonary vessels. The large space in the thoracic cavity is a risk factor, allowing the lung or lobes to rotate after segmentectomy or lobectomy. Even complete fissures without pleural adhesions or long bronchovascular vessels can cause lung torsion.[1][4][10][11][12][13][17] Lung torsion results in either part of the lobe or the entire lobe twisting along an axis. Twisting results in the obstruction of the bronchovascular tree, which eventually compromises the pulmonary arterial and venous circulation, along with the bronchial circulation. When the lobe is rotated more than 180 degrees, the bronchovascular pedicle is acutely obstructed, leading to atelectasis, then pulmonary infarction and necrosis. Bronchovascular obstruction will decrease arterial oxygen content due to ischemia.[13] Hypoxemia may result from intrapulmonary shunting, alveolar hypoventilation, and a ventilation-perfusion mismatch. Intrapulmonary shunting occurs if lobular veins are partially obstructed in an unventilated lung with some venous return. Alveolar hypoventilation occurs when the bronchus is kinked, reducing airflow from the airway into the bronchus. Kinking may also increase airway secretions, contributing to obstruction. If a ventilation-perfusion mismatch occurs, there is partial bronchial obstruction, but no venous return to the lobe due to complete vascular obstruction. Without proper oxygen delivery, the lung tissue can become nonviable. If not treated early, the lung tissue can become necrotic.[13][18][19][20]

No specific clinical signs or physical exam findings suggest lung torsion as the diagnosis. Nonspecific clinical signs include fever, chest pain, shortness of breath, and cough.[16] The most common symptoms, however, are dyspnea, fever, and chest pain.[16] Most of these symptoms appear 4 to 14 days after a thoracic surgical procedure, trauma, or any other triggering event. Some patients were even asymptomatic and showed no clinical signs. Physical examination findings can reveal hypoxia, respiratory discomfort, and tachypnea.[1][13][16][18][21] Radiological imaging, however, is required to confirm the diagnosis of lung torsion.[22]

Initial laboratory tests can show leukocytosis, but this condition is not always present. Arterial blood gas may appear normal and not reflect hypoxia; therefore, the diagnosis is based on radiologic imaging.[2] Radiography can show worsening consolidation and, sometimes, disruption of the pulmonary artery. Anatomic abnormalities and pulmonary opacities can also be seen on radiographic imaging. Serial radiographs can show progression of consolidation, especially if pneumonia is superimposed on lung torsion.[16][23][24] Bronchoscopy can also reveal findings indicating lung torsion. In previous case series, bronchoscopy revealed obstruction, in which the bronchoscope could not be advanced into the bronchus due to narrowing of the passageway. Bronchial stenosis and a fish-mouth orifice, or evidence of twisting or extrinsic compression, could be seen through bronchoscopy. Early identification of lung torsion using bedside bronchoscopy can preserve the lung tissue without requiring a pneumonectomy.[25] However, bronchoscopy does not always reveal narrowing or diagnose lung torsion; therefore, a computed tomography (CT) scan is required to confirm the diagnosis.[16][18][26] A CT scan can show bronchial artery obstruction, lobar opacification, atelectasis, or lobular collapse.[27][28] Vascular and bronchial structures can appear stenosed, obstructed, or inverted on imaging and may present as the antler sign.[29][30] Airway obstruction can reveal narrowing of the affected bronchus in the tracheobronchial tree. The lung can rotate at various angles. However, results from one case series showed that the lobe was rotated about 180 degrees in most cases. Follow-up CT scans can indicate changes in lesion position as lung torsion progresses. The presence of an antler sign on a contrast-enhanced chest CT, along with evidence of bronchial obstruction or abnormal fissure orientation, indicates lung torsion and warrants confirmation with 3-dimensional CT reconstructions.[29] CT angiography can show abrupt truncation and pulmonary artery obstruction. CT angiography images have also revealed interlobular septal thickening in the displaced lobe and venous congestion. Sometimes, abnormal lobe displacement can reveal a fissure. If the lung tissue has become necrotic, imaging will reveal the loss of parenchymal and pulmonary vascular integrity.[2][16][18][26][29]

Patients treated early, before necrosis occurs, can have viable tissue preserved. Results from case studies showed that patients who underwent detorsion of the rotated lung could regain full function as the lung re-expanded. Once the lungs have undergone detorsion, they must be fixed between the involved lung and the surrounding tissue using sutures or staples.[31] If the lung cannot be detorsed or detorsion fails, lobectomy must be performed; detorsion must be performed within the first few hours of diagnosis to save a viable lung. If more time passes, the lung may already have irreversible ischemic damage, and it may be safer to perform a resection without detorsion. Resection without detorsion would prevent inflammatory markers that accumulate during torsion from leaking into the rest of the body and causing multiorgan failure. For damaged tissue, it is best to keep the lung rotated until the pulmonary veins are clamped to prevent systemic release of inflammatory markers. Once safely clamped, a clinical decision can be made whether the lung can undergo detorsion or if resection should occur. Delayed treatment can also cause a clot to form, resulting in pulmonary embolism or stroke. An intravenous heparin infusion can be used as prophylaxis to prevent this complication. Conservative management has been found to result in recurrent pneumonia, eventually leading to death. Very few cases had complications after fixation, including pneumonia, air leaks, or emphysema. Most surgical procedures were performed without complications intraoperatively and postoperatively.[18][32][33][34]

Findings from studies showed that misdiagnosis occurred in 18.3% of patients with lung torsion. Most differentials can be excluded with a CT scan, CT angiography, or bronchoscopy, given the abnormal lobular placement. Diagnosis is confirmed with the vascular and airway obstructions seen on the CT scans. The differential diagnosis of lung torsion includes the following possibilities: Hemothorax Hemorrhage Pneumonia (infectious versus aspiration) Contusion (after sublobar resection; can appear like airspace consolidation that resolves after a few days) Lung gangrene Parenchymal infection Atelectasis Tumor Loculated effusion Emphysema Inadvertent ligation of the hilum Diaphragmatic herniation Leakage of the anastomosis site [13][14][16][35][36]

Prognosis is poor if lung torsion is treated late or if the patient develops sepsis, leading to lung tissue ischemia. The mortality rate was found to be as high as 8.3%.[16] Higher mortality rates were associated with whole-lung torsion compared with lobar torsion.[16] Findings from studies showed similar survival rates between indirect repositioning and direct repositioning. Direct resection had higher mortality. Mortality from lung torsion was found to be highest in trauma patients at 22.2%, followed by thoracic surgical procedures at 8.8% and spontaneous lung torsion at 3.1%.[16][37]

Correction of lung torsion is an emergent surgical procedure with many associated complications, including the following: Pneumonia Cerebrovascular accident Necrosis of the lung tissue Hemorrhage Vocal cord injury Bronchopleural fistulae Pulmonary embolism Postthoracic surgery noncardiogenic pulmonary edema Atelectasis Bronchospasm Respiratory failure Air leak, including pneumothorax, pneumomediastinum, pneumopericardium Emphysema [13][38][39][40][41][42]

Lung torsion can be identified on radiography, CT scan, or bronchoscopy. However, the diagnosis must be confirmed with a CT scan. Lung torsion is a life-threatening condition in which bronchovascular and airway compromise occur. If not treated promptly, lung necrosis can occur. Detorsion of the lung or lobectomy is the recommended treatment. If a thoracic surgical procedure is performed, pneumopexy of the lung lobe should be performed to prevent lung torsion. After lobectomy or segmentectomy, the remaining lobe should be stapled or sutured to keep it fixed; however, this is not commonly practiced as part of prophylactic treatment. A postoperative follow-up would require monitoring for air leaks. Clinicians should consider an intravenous heparin infusion for prophylaxis against pulmonary embolism.

If a thoracic surgical procedure, such as video-assisted thoracic surgery or lobectomy, is performed, stapling the lung or performing a pneumopexy of the lobe should be considered to prevent lung torsion. Lung torsion is a diagnosis that must be made promptly, typically via radiologic imaging. Once a diagnosis is made, it is imperative to contact the thoracic surgical team to salvage the lung. Coordination and rapid, effective communication among interprofessional care team members, including clinicians and surgeons, radiologists, nurses, and surgical assistants, are essential to ensure a timely diagnosis and correction of this potentially fatal condition.