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Postpneumonectomy Syndrome: A Spectrum of Clinical Presentations

2007; Elsevier BV; Volume: 83; Issue: 3 Linguagem: Inglês

10.1016/j.athoracsur.2006.08.021

1552-6259

Eric L.R. Bédard, Karl Uy, Shaf Keshavjee,

Dysphagia Assessment and Management

Postpneumonectomy syndrome has classically been described as a late complication after pneumonectomy where gradually increasing shortness of breath develops secondary to mediastinal shift. We present our experience and a review of the literature demonstrating a variety of clinical scenarios that, when necessary, were successfully managed with mediastinal repositioning. Postpneumonectomy syndrome has classically been described as a late complication after pneumonectomy where gradually increasing shortness of breath develops secondary to mediastinal shift. We present our experience and a review of the literature demonstrating a variety of clinical scenarios that, when necessary, were successfully managed with mediastinal repositioning. The onset of shortness of breath secondary to postpneumonectomy syndrome is an unusual complication, more commonly occurring after right pneumonectomy, that has been described in both children and adults [1Rasch D.K. Grover F.L. Schnapf B.M. Clarke E. Pollard T.G. Right pneumonectomy syndrome in infancy treated with an expandable prosthesis.Ann Thor Surg. 1990; 50: 127-129Abstract Full Text PDF PubMed Scopus (36) Google Scholar, 2Grillo H.C. Shepard J.O. Mathisen D.J. Kanarek D.J. Postpneumonectomy syndrome: diagnosis, management, and results.Ann Thor Surg. 1992; 54: 638-651Abstract Full Text PDF PubMed Scopus (115) Google Scholar]. The pathophysiology has been ascribed to an extreme shift and rotation of the mediastinum into the pneumonectomy space, resulting in bronchial compression and subsequent dyspnea [2Grillo H.C. Shepard J.O. Mathisen D.J. Kanarek D.J. Postpneumonectomy syndrome: diagnosis, management, and results.Ann Thor Surg. 1992; 54: 638-651Abstract Full Text PDF PubMed Scopus (115) Google Scholar]. We describe our experience with 4 patients presenting with widely differing clinical manifestations of the syndrome. A 30-year-old woman underwent a left pneumonectomy through a thoracotomy. She recovered well, and during follow-up was noted to have rotation of the mediastinum posterior and left (Fig 1A). A computed tomography (CT) scan of the chest showed that her right bronchus intermedius was compressed (Fig 1B), but she was completely asymptomatic. A 43-year-old man underwent a sternotomy and left intrapericardial pneumonectomy. Three years later, progressive shortness of breath developed. Pulmonary function tests revealed forced vital capacity (FVC) of 70% predicted, forced mid expiratory flow rate of 11% predicted, and airway resistance of 243% predicted. A CT scan demonstrated an ipsilateral aortic arch and right middle lobe and bronchus intermedius narrowing, which was confirmed by bronchoscopy. The patient underwent a left thoracotomy for mediastinal repositioning and placement of two saline tissue expanders (Mentor, Santa Barbara, CA) containing a total of 1300 mL. The patient made a rapid recovery to full activities. A 59-year-old woman underwent a left pneumonectomy. During the following year, she experienced dysphagia. A barium swallow showed mild hold-up in the mid esophagus, but results of bronchoscopy and esophagogastroscopy were normal. Esophageal motility studies showed no motor abnormalities. Her symptoms progressed, and a chest CT scan demonstrated an ipsilateral aortic arch with the mediastinum shifted to the left and a distended proximal esophagus compressed between the left atrium and descending thoracic aorta (Fig 2A). A subsequent barium swallow confirmed the shifted and twisted esophagus into the left pneumonectomy space (Fig 2B). The patient underwent a redo left thoracotomy and mediastinal repositioning using saline-filled (1950 mL) prostheses (Mentor). Her dysphagia immediately resolved; however, she noticed a new onset of shortness of breath. A cardiac work-up was negative, and pulmonary function tests confirmed the clinical suspicion of compression of her right lung by the prostheses (FVC pre-repositioning 82% predicted versus post-repositioning 48% predicted). Her dyspnea, however, has largely resolved obviating the need for surgical intervention. A 64-year-old man underwent a right carinal pneumonectomy. He presented to a peripheral emergency department 5 weeks later with rapidly progressive shortness of breath. On arrival, he required more than 80% oxygen to maintain oxygen saturations of 92%. His initial chest roentgenogram was read as unremarkable, and a provisional diagnosis of pulmonary embolus was made, and he was heparinized. A spiral CT angiogram of the chest showed no embolus but did reveal left lower lobe collapse associated with compression of the left lower lobe bronchus between the pulmonary artery and descending thoracic aorta (Fig 3A). The patient was transferred to our institution, where an urgent flexible and rigid bronchoscopy confirmed left lower lobe bronchial compression (Fig 3B). An 8-mm-diameter silastic stent was placed in the left lower lobe bronchus. The patient made an uneventful recovery, and a repeat CT showed full reexpansion of the left lower lobe with the stent in place (Fig 3C). The patient underwent a redo right thoracotomy 3 months later for mediastinal repositioning with a saline-filled prostheses (1700 mL) and bronchial stent removal. Postoperative bronchoscopy revealed a widely patent left lower lobe orifice (Fig 3D). The classic description of postpneumonectomy syndrome is as a late complication of right pneumonectomy caused by a shift of the mediastinum into the postpneumonectomy space, with posterior displacement and counterclockwise rotation [2Grillo H.C. Shepard J.O. Mathisen D.J. Kanarek D.J. Postpneumonectomy syndrome: diagnosis, management, and results.Ann Thor Surg. 1992; 54: 638-651Abstract Full Text PDF PubMed Scopus (115) Google Scholar]. This results in compression of the distal trachea and left mainstem bronchus across either the aorta or vertebral column [2Grillo H.C. Shepard J.O. Mathisen D.J. Kanarek D.J. Postpneumonectomy syndrome: diagnosis, management, and results.Ann Thor Surg. 1992; 54: 638-651Abstract Full Text PDF PubMed Scopus (115) Google Scholar]. In their landmark report, Grillo and colleagues [2Grillo H.C. Shepard J.O. Mathisen D.J. Kanarek D.J. Postpneumonectomy syndrome: diagnosis, management, and results.Ann Thor Surg. 1992; 54: 638-651Abstract Full Text PDF PubMed Scopus (115) Google Scholar] described a similar phenomenon after left pneumonectomy only in the presence of a right aortic arch. Two patients in the current report were found to have the syndrome after a left pneumonectomy; however, neither had a right sided aortic arch, similar to patients described by Shamji and colleagues [3Shamji F.M. Deslauriers J. Daniel T.M. Matzinger F.R. Mehran R.J. Todd T.R.J. Postpneumonectomy syndrome with an ipsilateral aortic arch after left pneumonectomy.Ann Thor Surg. 1996; 62: 1627-1631Abstract Full Text Full Text PDF PubMed Scopus (36) Google Scholar]. They described the compression of the distal right mainstem bronchus and bronchus intermedius between the right pulmonary artery and the thoracic spine due to posterior displacement and clockwise rotation of the mediastinum [3Shamji F.M. Deslauriers J. Daniel T.M. Matzinger F.R. Mehran R.J. Todd T.R.J. Postpneumonectomy syndrome with an ipsilateral aortic arch after left pneumonectomy.Ann Thor Surg. 1996; 62: 1627-1631Abstract Full Text Full Text PDF PubMed Scopus (36) Google Scholar]. There is usually a significant time interval before the onset of symptoms secondary to a postpneumonectomy syndrome [2Grillo H.C. Shepard J.O. Mathisen D.J. Kanarek D.J. Postpneumonectomy syndrome: diagnosis, management, and results.Ann Thor Surg. 1992; 54: 638-651Abstract Full Text PDF PubMed Scopus (115) Google Scholar]. A more acute course has been presented in the pediatric literature, where children may be at risk for a more rapid course given their increased mediastinal mobility and lung compliance [1Rasch D.K. Grover F.L. Schnapf B.M. Clarke E. Pollard T.G. Right pneumonectomy syndrome in infancy treated with an expandable prosthesis.Ann Thor Surg. 1990; 50: 127-129Abstract Full Text PDF PubMed Scopus (36) Google Scholar, 2Grillo H.C. Shepard J.O. Mathisen D.J. Kanarek D.J. Postpneumonectomy syndrome: diagnosis, management, and results.Ann Thor Surg. 1992; 54: 638-651Abstract Full Text PDF PubMed Scopus (115) Google Scholar]. It is unclear why such a rapid onset of dyspnea developed in patient 4 in this report. In addition, the airway obstruction developed in the left lower lobe bronchus, an atypical location. The right carinal pneumonectomy likely shortened his left main stem bronchus and caused his lower lobe bronchus to be compressed over the aorta as the mediastinum shifted and rotated into the pneumonectomy space. Although dyspnea is the classic symptom associated with postpneumonectomy syndrome, the current report describes a patient with progressive dysphagia after left pneumonectomy. After multiple investigations, the symptom was ascribed to postpneumonectomy syndrome given the mid esophageal tortuosity and obstruction from the shift of the mediastinum and apparent trapping of the esophagus between the heart and aorta. A wide variety of treatment options have been described for these patients, ranging from simple bronchial stent insertion to aortic division and bypass grafting in addition to mediastinal repositioning [2Grillo H.C. Shepard J.O. Mathisen D.J. Kanarek D.J. Postpneumonectomy syndrome: diagnosis, management, and results.Ann Thor Surg. 1992; 54: 638-651Abstract Full Text PDF PubMed Scopus (115) Google Scholar, 4Wasserman K. Jamplis R.W. Lash H. Brown H.V. Cleary M.G. Lafair J. Post-pneumonectomy syndrome surgical correction using silastic implants.Chest. 1979; 75: 60-78Crossref Scopus (65) Google Scholar, 5Harney M.S. Lacy P.D. O’Neil S. Walsh M. Nitinol stent insertion for post-pneumonectomy syndrome.J Laryng Otol. 2001; 115: 938-939PubMed Google Scholar]. Currently, the most common approach is through a thoracotomy, with division of adhesions, mediastinal repositioning, and insertion of saline-filled prostheses [2Grillo H.C. Shepard J.O. Mathisen D.J. Kanarek D.J. Postpneumonectomy syndrome: diagnosis, management, and results.Ann Thor Surg. 1992; 54: 638-651Abstract Full Text PDF PubMed Scopus (115) Google Scholar, 3Shamji F.M. Deslauriers J. Daniel T.M. Matzinger F.R. Mehran R.J. Todd T.R.J. Postpneumonectomy syndrome with an ipsilateral aortic arch after left pneumonectomy.Ann Thor Surg. 1996; 62: 1627-1631Abstract Full Text Full Text PDF PubMed Scopus (36) Google Scholar, 4Wasserman K. Jamplis R.W. Lash H. Brown H.V. Cleary M.G. Lafair J. Post-pneumonectomy syndrome surgical correction using silastic implants.Chest. 1979; 75: 60-78Crossref Scopus (65) Google Scholar]. To better assess mediastinal position intraoperatively for patients presenting with bronchial compression, intraoperative bronchoscopy is recommended to ensure improvement in airway patency before chest closure. We have, on occasion, used saline filled protheses equipped with a subcutaneously placed injection port to adjust prosthesis size by adding or removing saline. However, this was found to be clinically unnecessary, and the subcutaneous port risks inducing added discomfort to the patient. Harney and colleagues [5Harney M.S. Lacy P.D. O’Neil S. Walsh M. Nitinol stent insertion for post-pneumonectomy syndrome.J Laryng Otol. 2001; 115: 938-939PubMed Google Scholar] described the use of an expandable nitinol bronchial stent as first-line therapy; however, consideration should be given to the patient’s age and the possibility of future stent migration or erosion. In addition, the use of self-expanding stents for benign conditions often leads to further complications with obstruction secondary to granulation tissue. Published reports describing the use of prostheses to maintain mediastinal position appear to most often use approximately 1 liter of fluid. Over-correction of mediastinal position is possible in this scenario, resulting in symptoms from compression of the remaining lung parenchyma [3Shamji F.M. Deslauriers J. Daniel T.M. Matzinger F.R. Mehran R.J. Todd T.R.J. Postpneumonectomy syndrome with an ipsilateral aortic arch after left pneumonectomy.Ann Thor Surg. 1996; 62: 1627-1631Abstract Full Text Full Text PDF PubMed Scopus (36) Google Scholar]. Shamji and colleagues [3Shamji F.M. Deslauriers J. Daniel T.M. Matzinger F.R. Mehran R.J. Todd T.R.J. Postpneumonectomy syndrome with an ipsilateral aortic arch after left pneumonectomy.Ann Thor Surg. 1996; 62: 1627-1631Abstract Full Text Full Text PDF PubMed Scopus (36) Google Scholar] described a patient requiring a redo thoracotomy on postoperative day 5 after symptoms worsened after repositioning and the instillation of 1600 mL of saline in prostheses. The dysphagia in the second patient described resolved after repositioning, but then an onset of dyspnea occurred that, fortunately, resolved. Caution should be used if large-volume prostheses appear necessary to maintain mediastinal position when performing this procedure. In conclusion, although most patients with extreme mediastinal shifting postpneumonectomy are asymptomatic, the gradual onset of dyspnea after pneumonectomy remains the most common presentation of postpneumonectomy syndrome. The patients described in this report demonstrate a wide clinical spectrum. We believe that once this difficult diagnosis has been established, the optimal treatment strategy for symptomatic patients is mediastinal repositioning using saline-filled prostheses.