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Pulmonary torsion after cardiac surgery in two infants: Review of pediatric literature
Pulmonary Torsion After Cardiac Surgery in Two Infants: Review of Pediatric Literature By Daniele Alberti, Alessandro Borsellino, Lucia Migliazza, Mario Leo Brena, Aurelio Sonzogni, Maurizio Cheli, Angelo Colombo, and Giuseppe Locatelli Bergamo, Italy
Torsion of a lung or a lobe (LT) is a severe, sometimes life-threatening event that may occur spontaneously, after trauma, or after cardiac or thoracic surgery. The authors report on 2 prematurely born neonates who had LT after cardiac surgery. Both patients successfully underwent pulmonary lobectomy, which seems to be the best surgical approach. Given that careful anatomic unfolding of the lung and its reinflation under vision at the end of a cardiac or thoracic operation is deemed crucial to avoid LT, the authors suggest that, in case of a complete pulmonary fissure and/or
free long bronchovascular pedicle, lobe fixation should be accomplished, too. Because of its rarity, we could find only 6 well-documented reports of LT diagnosed in children, whereas another 3 cases were quoted without clinical details. The pediatric literature is reviewed. J Pediatr Surg 39:1719-1723. © 2004 Elsevier Inc. All rights reserved.
T
Case 2
ORSION OF THE LUNG or one of its lobes (LT), is a rare life-threatening event that may occur spontaneously, after trauma, or after thoracic surgery. Only 6 cases have been thoroughly reported in children. We present 2 infants in whom LT developed after cardiovascular surgery. Etiology, diagnosis, and treatment of LT are discussed, and the pediatric literature is reviewed. CASE REPORTS
Case 1 A 1.6-kg preterm neonate, delivered at 29 weeks’ gestation, was referred to our department of cardiovascular surgery presenting with pulmonary artery atresia and ventricular septal defect. The baby underwent surgical intervention at 20 days of life; a modified BlalockTaussig shunt with a 3.5 polytetrafluoroethylene tube was undertaken through a right posterolateral thoracotomy. A thoracic drain was inserted at the end of the procedure. The early postoperative course was uneventful with normal cardiopulmonary function in spite of persistent opacification of the right hemithorax without madiastinal shift in serial chest radiographs associated with diminished breath sounds on the corresponding area. Despite repeated efforts of endotracheal suctioning and physiotherapy, radiologic findings persisted, and replacement of the thoracic drain was accomplished on the third postoperative day. Because neither liquid nor blood was drained (Fig 1), LT was suspected, and an exploratory thoracotomy was performed. A 360° clockwise torsion of the right middle lobe (RML) was detected with occlusion of its relatively long bronchovascular bundle at hilum. The lobe was engorged, not aerated, with a blue-black hemorragic appearance. It was noted that the oblique fissure was essentially complete. The lobe then was rotated back and quickly removed. Histologic examination showed stasis and hemorragic pulmonary necrosis. The post operative course was uneventful, and the infant was discharged on postoperative day 8 with normal chest x-ray. At the age of 9 months, he underwent further palliation of the cardiac anomaly by means of a bidirectional Glenn procedure. At 5 years of follow-up the child is doing well with normal cardiopulmonary function.
INDEX WORDS: Lung torsion, lobar torsion, complete pulmonary fissure.
A 1.6-kg girl was delivered at 29 weeks’ gestation by cesarian section because of placental abruption. Surfactant was given, and high-frequency oscillatory ventilation was instituted immediately because of severe respiratory distress. On day 5 of life, surgical closure of the ductus arteriosus was performed through a left posterolateral thoracotomy because there was significant hemodynamic imbalance. The patient was discharged at 47 days of age. Two weeks later, the infant was readmitted to the neonatal intensive care unit because of severe dyspnea and bradycardia that needed cardiopulmonary resuscitation and ventilatory support. A plain chest x-ray showed an hyperaeration with retrosternal herniation of the left upper lobe and displacement of heart and trachea to the right hemithorax (Fig 2). High-frequency oscillatory ventilation (HFOV) was instituted. At serial chest x-rays, emphysema resolved 6 hours after admission but unfortunately recurred 24 hours later with the patient’s clinical deterioration and warranted increasing ventilatory support. Therefore, 30 hours after her admission, the baby underwent left posterolateral thoracotomy. The left upper lobe (LUL) appeared 6 times larger than normal and surprisingly twisted by 180° in clockwise direction around a long free bronchovascular pedicle. No parenchymal bridges to the lower lobe were found. The LUL then was removed. Histology findings showed emphysematous transformation with normal bronchial partition, thus, ruling out congenital lobar emphysema. The patient was discharged home 19 days after surgery. At 5 years of follow-up, the baby is quite healthy with normal pulmonary function.
From the Departments of Pediatric Surgery and Pathology and the Neonatal Intensive Care Unit, Ospedali Riuniti di Bergamo, Bergamo, Italy. Address reprint requests to Alessandro Borsellino, Unita` Operativa di Chirurgia Pediatrica, Ospedali Riuniti di Bergamo, L.go Barozzi, 1–24128 Bergamo, Italy. © 2004 Elsevier Inc. All rights reserved. 0022-3468/04/3911-0022$30.00/0 doi:10.1016/j.jpedsurg.2004.07.025
Journal of Pediatric Surgery, Vol 39, No 11 (November), 2004: pp 1719-1723
1719
1720
ALBERTI ET AL
Fig 1. Chest x-ray. Persistent opacification of the right hemithorax after replacement of the thoracic drain on postoperative day 3; no outflow occurred, suggesting LT.
DISCUSSION
Torsion of the lung or one of its lobes (LT) is a severe but fortunately rare event. Rotation of the bronchovascular pedicle results in airway obstruction and vascular compromise. Little more than 80 cases have been reported in adults7-23 and only 9 in the pediatric age group, 5 in children and 4 in infants (Table 1).1-6 Unfortunately, 3 affected children after operation for congenital heart
Fig 2. Chest x-ray. Hyperinflation of the LUL with lung herniation and mediastinal shift; previous closure of a patent ductus arteriosus by a metallic clip.
disease,22 could not be included in the current discussion because of lack of clinical details. Among children, LT has been reported after chest trauma, after transthoracic nonpulmonary surgical procedures, and spontaneously (Table 1). Different predisposing factors have been addressed: in case of traumatic LT (cases 1 through 4), progressive consolidation or atelectasis changes associated with hemothorax and/or
Intraoperative findings
Etiology
Study
Age at Symptoms
Original Disease
Treatment
Radiologic Findings
Diagnostic Delay 6 wk
Lung Appearance
Lobe
Rotation
LL
180° CW
Hemorrhagic necrosis of the whole LL except segment 6
LL
? CW
Hemorrhagic necrosis whole LL, RL congested necropsy findings
Treatment LUL ⫹ basal segment LLL resection
Outcome
Parks1
7 yr
Thoracic and abdominal blunt trauma: rib fractures, spleen rupture
Splenectomy
Progressive consolidation of the LL
Stratemeier and Barry2
6 yr
Thoracic blunt trauma: rib fractures, bilateral pneumothorax, shock
Resuscitation
Progressive consolidation of the upper half of lungs
Daughtry3
7 yr
Thoracic and abdominal blunt trauma: rib fractures, spleen rupture
Splenectomy
Progressive consolidation of the LL
7 wk
LL
180° CW
Hemorrhagic necrosis of the whole LL except segment 6
LUL ⫹ basal segment LLL resection
Complete recovery
Selmonosky et al4
13 yr
Severe blunt thoracic trauma: hemopneumothorax
Chest tube
Persistent opacification of the RL
2d
RML
360° CW
Hemorragic necrosis of the RML
RML resection
Complete recovery
Hislop and Reid5
2 mo
Bronchiolitis
Medical treatment
Persistent LUL emphysema, mediastinal shift
5 wk
LUL
180° CW
3-4 times enlargement of the LUL
LUL resection
Complete recovery
Fu et al6
1.5 yr
Hiatal hernia
Posterolateral thoracotomy, Belsey Mark IV
2d
LL
90° CW
LL purple, edematous
Detorsion
Shrunken nonfunctioning LL
Current report
20 d
Ventricular septal defect, pulmonary artery atresia, mitral straddling
Posterolateral thoracotomy, Blallock shunt
Persistent opacification of the right thorax
3d
RML
360° CW
Hemoragic necrosis RML
RML resection
Complete recovery
Current report
2 mo
Patent ductus arteriosus
Posterolateral thoracotomy, ductal closure
Persistent LUL emphysema, mediastinal shift
1d
LUL
180° CW
6 times enlargement of the LUL
LUL resection
Complete recovery
Complete recovery
Died 7 hours after admission
POSTOPERATIVE PULMONARY TORSION
Table 1. Characteristics, Treatment, and Outcome of Pulmonary Torsion in Children. Literature Review and Current Cases
Abbreviations: CW, clockwise; LL, left lung; LLL, left lower lobe; LUL, left upper lobe; RML, right medium lobe. 1721
1722
ALBERTI ET AL
pneumothorax could have provided a milieu of easily displaceable free air or fluids with rearrangement of the lobes. In the remaining 2 reported cases, 1 with spontaneous LT (case 5) and 1 after thoracotomy (case 6), no explanation was found at surgery. Regarding our 2 patients, a complete interlobar fissure (case 7) and a relatively free long pedicle coupled with the absence of any parenchymal bridges between the contiguous lobes (case 8) were most likely to facilitate the rotation process that lead to LT. This condition represents a diagnostic challenge: respiratory failure leads to striking deterioration of the patient’s condition while arterial blood gases remain adequate because lung perfusion is preserved in uninvolved areas.8 Radiology can help with diagnosis, although no specific patterns exist. Nevertheless, LT should be considered in every patient with rapid opacification of the pulmonary parenchyma on serial postoperative chest radiographs.12-13 As observed in one of our patients, increasing density and enlarging size of a lobe after trauma or thoracic surgery should suggest the potential for LT.15,16-23 Atelectasis can be excluded because of progressive enlargement of the involved area caused by hemorragic infarction and also because of absence of mediastinal shift. Abnormal location of bronchovascular marking, bronchial cut off or distortion, and serial positional change of the affected lobe have been described.8 In case of complete lung torsion, total opacification of the affected hemithorax may mimic hemothorax or pleural effusion.12 In such instances, computed tomography (CT) scan probably proves the most sensitive diagnostic tool and should be performed promptly especially when thoracentesis fails to drain fluid or blood or when ultrasonography shows the absence of pleural effusion. In case of lobar torsion causing emphysema and me-
diastinal shift, as encountered in 2 infants (cases 5 and 7), differential diagnosis has to be made with congenital lobar emphysema (CLE) and pneumothorax: clinical history and eventually previous chest x-rays will help in differentiating between these conditions. However, despite various radiologic investigations, diagnosis remained uncertain until surgery in all pediatric patients. Maybe bronchoscopy could be of diagnostic value, as in adults, but it was never performed in affected children. Histologic examination was consistent with hemorragic necrosis and parenchymal infarction owing to vascular compromise in 6 children, whereas lobar emphysema produced by check-valve effect of the constricted bronchus with air trapping was present in 2 cases. This mechanism may account for spontaneous transient resolution of emphysema as observed in our latter case. In both infants, a 180° torsion involved the LUL. Once LT is detected, a conservative approach, namely, lung or lobe detorsion, may be attempted only when torsion is diagnosed within a few hours from its onset and in the presence of a moderate degree of vascular impairment7-9; however, simple lung detorsion performed in 1 child resulted in a nonfunctioning shrunken left lung, which was later removed.6 According to the literature and to our own experience, we believe that resection of the involved lobe or entire lung is the best curative option to lower any additional morbidity and mortality. Besides, if careful anatomic unfolding of the lobes with inflation under vision before chest closure is mandatory to avoid LT, we suggest that pulmonary lobe fixation should be accomplished to prevent further morbility in every child undergoing cardiothoracic surgery, in whom a complete pulmonary fissure and/or free long pedicle is detected.
REFERENCES 1. Parks R: Traumatic torsion of the lung. Radiology 67:582-583, 1952 2. Stratemeier EH, Barry JW: Torsion of the lung following thoracic trauma. Radiology 62:726-727, 1954 3. Daughtry DC: Traumatic torsion of the lung. N Engl J Med 258:385-388, 1957 4. Selmonosky CA, Flege JB Jr, Ehrenhaft JL: Torsion of the lobe of the lung due to blunt chest trauma. Ann Thorac Surg 4:166-170, 1967 5. Hislop A, Reid L: New pathological findings in emphysema in childhood: Overinflation of a normal lobe. Thorax 26:190-194, 1971 6. Fu J, Chen CL, Wu JY, et al: Lung torsion: Survival of a patient whose hemorragic infarcted lung remained in situ after torsion. J Thorac Cardiovasc Surg 99:1112-1114, 1990 7. Huang TY, Cho SR: Torsion of the lung without trauma. Diag Radiol 143:25-26, 1979 8. Kelly MV, Kyger ER, Miller WC: Postoperative lobar torsion and gangrene. Thorax 72:501-504, 1977 9. Chambers RF, Sweeney DF: Gangrenous sequestration of remaining lobe following lobectomy. Ann Thorac Surg 5:156-161, 1968
10. Oddi MA, Taugott RC, Will RJ, et al: Unrecognized intraoperative torsion of the lung. Surgery 89:390-393, 1981 11. Pintsein MZ, Winer-Muram H, Eastridge C, et al: Middle lobe torsion following right upper lobectomy. Radiology 155:580, 1985 12. Felson B: Lung torsion: Radiographic findings in nine cases. Radiology 162:631-638, 1987 13. Larsson S, Lepore V, Dernevik L, et al: Torsion of a lung lobe: Diagnosis and treatment. Thorac Cardiovasc Surg 36:281-283, 1988 14. Schamaun M: Postoperative pulmonary torsion: Report of a case and survey of the literature including spontaneous and posttraumatic torsion. Thorac Cardiovasc Surg 42:116-121, 1994 15. Munk PL, Vellet AD, Zwirewich C: Torsion of the upper lobe of the lung after surgery: Findings on pulmonary angiography. AJR 157:471-472, 1991 16. Chan MCK, Scott JM, Mercer CD, et al: Intraoperative wholelung torsion producing pulmonary venous infarction. Ann Thorac Surg 57:1330-1331, 1994 17. Kucich VA, Villareal JR, Schwartz DB: Left upper lobe torsion following lower lobe resection: Early recognition of a rare complication. Chest 95:1146-1147, 1989
POSTOPERATIVE PULMONARY TORSION
18. Livaudais W, Cavanaugh DG, Geer TM: Rapid postoperative thoracotomy for torsion of the left lower lobe: Case report. Milit Med 145:698-699, 1980 19. Mullin MJ, Zumbro GL, Fishback ME, et al: Pulmonary lobar gangrene complicating lobectomy. Ann Surg 175:62-66, 1972 20. Louis JR, Daffner RH: Torsion of the lung causing refractory hypoxemia. J Trauma 27:687-688, 1987
1723
21. Hislop A, Reid L: New pathological findings in emphysema of childhood. Overinflation of a normal lobe. Thorax 26:190-194, 1971 22. Wong PS, Goldstraw P: Pulmonary torsion: A questionnaire survey and a survey of the literature. Ann Thorac Surg 54:286-28, 1992 23. Cable DG, Deschamps C, Allen MS, et al: Lobar torsion after pulmonary resection: Presentation and outcome. J Thorac Cardiovasc Surg 122:1091-1093, 2001
Torsion of a lung or a lobe (LT) is a severe, sometimes life-threatening event that may occur spontaneously, after trauma, or after cardiac or thoracic surgery. The authors report on 2 prematurely born neonates who had LT after cardiac surgery. Both patients successfully underwent pulmonary lobectomy, which seems to be the best surgical approach. Given that careful anatomic unfolding of the lung and its reinflation under vision at the end of a cardiac or thoracic operation is deemed crucial to avoid LT, the authors suggest that, in case of a complete pulmonary fissure and/or
free long bronchovascular pedicle, lobe fixation should be accomplished, too. Because of its rarity, we could find only 6 well-documented reports of LT diagnosed in children, whereas another 3 cases were quoted without clinical details. The pediatric literature is reviewed. J Pediatr Surg 39:1719-1723. © 2004 Elsevier Inc. All rights reserved.
T
Case 2
ORSION OF THE LUNG or one of its lobes (LT), is a rare life-threatening event that may occur spontaneously, after trauma, or after thoracic surgery. Only 6 cases have been thoroughly reported in children. We present 2 infants in whom LT developed after cardiovascular surgery. Etiology, diagnosis, and treatment of LT are discussed, and the pediatric literature is reviewed. CASE REPORTS
Case 1 A 1.6-kg preterm neonate, delivered at 29 weeks’ gestation, was referred to our department of cardiovascular surgery presenting with pulmonary artery atresia and ventricular septal defect. The baby underwent surgical intervention at 20 days of life; a modified BlalockTaussig shunt with a 3.5 polytetrafluoroethylene tube was undertaken through a right posterolateral thoracotomy. A thoracic drain was inserted at the end of the procedure. The early postoperative course was uneventful with normal cardiopulmonary function in spite of persistent opacification of the right hemithorax without madiastinal shift in serial chest radiographs associated with diminished breath sounds on the corresponding area. Despite repeated efforts of endotracheal suctioning and physiotherapy, radiologic findings persisted, and replacement of the thoracic drain was accomplished on the third postoperative day. Because neither liquid nor blood was drained (Fig 1), LT was suspected, and an exploratory thoracotomy was performed. A 360° clockwise torsion of the right middle lobe (RML) was detected with occlusion of its relatively long bronchovascular bundle at hilum. The lobe was engorged, not aerated, with a blue-black hemorragic appearance. It was noted that the oblique fissure was essentially complete. The lobe then was rotated back and quickly removed. Histologic examination showed stasis and hemorragic pulmonary necrosis. The post operative course was uneventful, and the infant was discharged on postoperative day 8 with normal chest x-ray. At the age of 9 months, he underwent further palliation of the cardiac anomaly by means of a bidirectional Glenn procedure. At 5 years of follow-up the child is doing well with normal cardiopulmonary function.
INDEX WORDS: Lung torsion, lobar torsion, complete pulmonary fissure.
A 1.6-kg girl was delivered at 29 weeks’ gestation by cesarian section because of placental abruption. Surfactant was given, and high-frequency oscillatory ventilation was instituted immediately because of severe respiratory distress. On day 5 of life, surgical closure of the ductus arteriosus was performed through a left posterolateral thoracotomy because there was significant hemodynamic imbalance. The patient was discharged at 47 days of age. Two weeks later, the infant was readmitted to the neonatal intensive care unit because of severe dyspnea and bradycardia that needed cardiopulmonary resuscitation and ventilatory support. A plain chest x-ray showed an hyperaeration with retrosternal herniation of the left upper lobe and displacement of heart and trachea to the right hemithorax (Fig 2). High-frequency oscillatory ventilation (HFOV) was instituted. At serial chest x-rays, emphysema resolved 6 hours after admission but unfortunately recurred 24 hours later with the patient’s clinical deterioration and warranted increasing ventilatory support. Therefore, 30 hours after her admission, the baby underwent left posterolateral thoracotomy. The left upper lobe (LUL) appeared 6 times larger than normal and surprisingly twisted by 180° in clockwise direction around a long free bronchovascular pedicle. No parenchymal bridges to the lower lobe were found. The LUL then was removed. Histology findings showed emphysematous transformation with normal bronchial partition, thus, ruling out congenital lobar emphysema. The patient was discharged home 19 days after surgery. At 5 years of follow-up, the baby is quite healthy with normal pulmonary function.
From the Departments of Pediatric Surgery and Pathology and the Neonatal Intensive Care Unit, Ospedali Riuniti di Bergamo, Bergamo, Italy. Address reprint requests to Alessandro Borsellino, Unita` Operativa di Chirurgia Pediatrica, Ospedali Riuniti di Bergamo, L.go Barozzi, 1–24128 Bergamo, Italy. © 2004 Elsevier Inc. All rights reserved. 0022-3468/04/3911-0022$30.00/0 doi:10.1016/j.jpedsurg.2004.07.025
Journal of Pediatric Surgery, Vol 39, No 11 (November), 2004: pp 1719-1723
1719
1720
ALBERTI ET AL
Fig 1. Chest x-ray. Persistent opacification of the right hemithorax after replacement of the thoracic drain on postoperative day 3; no outflow occurred, suggesting LT.
DISCUSSION
Torsion of the lung or one of its lobes (LT) is a severe but fortunately rare event. Rotation of the bronchovascular pedicle results in airway obstruction and vascular compromise. Little more than 80 cases have been reported in adults7-23 and only 9 in the pediatric age group, 5 in children and 4 in infants (Table 1).1-6 Unfortunately, 3 affected children after operation for congenital heart
Fig 2. Chest x-ray. Hyperinflation of the LUL with lung herniation and mediastinal shift; previous closure of a patent ductus arteriosus by a metallic clip.
disease,22 could not be included in the current discussion because of lack of clinical details. Among children, LT has been reported after chest trauma, after transthoracic nonpulmonary surgical procedures, and spontaneously (Table 1). Different predisposing factors have been addressed: in case of traumatic LT (cases 1 through 4), progressive consolidation or atelectasis changes associated with hemothorax and/or
Intraoperative findings
Etiology
Study
Age at Symptoms
Original Disease
Treatment
Radiologic Findings
Diagnostic Delay 6 wk
Lung Appearance
Lobe
Rotation
LL
180° CW
Hemorrhagic necrosis of the whole LL except segment 6
LL
? CW
Hemorrhagic necrosis whole LL, RL congested necropsy findings
Treatment LUL ⫹ basal segment LLL resection
Outcome
Parks1
7 yr
Thoracic and abdominal blunt trauma: rib fractures, spleen rupture
Splenectomy
Progressive consolidation of the LL
Stratemeier and Barry2
6 yr
Thoracic blunt trauma: rib fractures, bilateral pneumothorax, shock
Resuscitation
Progressive consolidation of the upper half of lungs
Daughtry3
7 yr
Thoracic and abdominal blunt trauma: rib fractures, spleen rupture
Splenectomy
Progressive consolidation of the LL
7 wk
LL
180° CW
Hemorrhagic necrosis of the whole LL except segment 6
LUL ⫹ basal segment LLL resection
Complete recovery
Selmonosky et al4
13 yr
Severe blunt thoracic trauma: hemopneumothorax
Chest tube
Persistent opacification of the RL
2d
RML
360° CW
Hemorragic necrosis of the RML
RML resection
Complete recovery
Hislop and Reid5
2 mo
Bronchiolitis
Medical treatment
Persistent LUL emphysema, mediastinal shift
5 wk
LUL
180° CW
3-4 times enlargement of the LUL
LUL resection
Complete recovery
Fu et al6
1.5 yr
Hiatal hernia
Posterolateral thoracotomy, Belsey Mark IV
2d
LL
90° CW
LL purple, edematous
Detorsion
Shrunken nonfunctioning LL
Current report
20 d
Ventricular septal defect, pulmonary artery atresia, mitral straddling
Posterolateral thoracotomy, Blallock shunt
Persistent opacification of the right thorax
3d
RML
360° CW
Hemoragic necrosis RML
RML resection
Complete recovery
Current report
2 mo
Patent ductus arteriosus
Posterolateral thoracotomy, ductal closure
Persistent LUL emphysema, mediastinal shift
1d
LUL
180° CW
6 times enlargement of the LUL
LUL resection
Complete recovery
Complete recovery
Died 7 hours after admission
POSTOPERATIVE PULMONARY TORSION
Table 1. Characteristics, Treatment, and Outcome of Pulmonary Torsion in Children. Literature Review and Current Cases
Abbreviations: CW, clockwise; LL, left lung; LLL, left lower lobe; LUL, left upper lobe; RML, right medium lobe. 1721
1722
ALBERTI ET AL
pneumothorax could have provided a milieu of easily displaceable free air or fluids with rearrangement of the lobes. In the remaining 2 reported cases, 1 with spontaneous LT (case 5) and 1 after thoracotomy (case 6), no explanation was found at surgery. Regarding our 2 patients, a complete interlobar fissure (case 7) and a relatively free long pedicle coupled with the absence of any parenchymal bridges between the contiguous lobes (case 8) were most likely to facilitate the rotation process that lead to LT. This condition represents a diagnostic challenge: respiratory failure leads to striking deterioration of the patient’s condition while arterial blood gases remain adequate because lung perfusion is preserved in uninvolved areas.8 Radiology can help with diagnosis, although no specific patterns exist. Nevertheless, LT should be considered in every patient with rapid opacification of the pulmonary parenchyma on serial postoperative chest radiographs.12-13 As observed in one of our patients, increasing density and enlarging size of a lobe after trauma or thoracic surgery should suggest the potential for LT.15,16-23 Atelectasis can be excluded because of progressive enlargement of the involved area caused by hemorragic infarction and also because of absence of mediastinal shift. Abnormal location of bronchovascular marking, bronchial cut off or distortion, and serial positional change of the affected lobe have been described.8 In case of complete lung torsion, total opacification of the affected hemithorax may mimic hemothorax or pleural effusion.12 In such instances, computed tomography (CT) scan probably proves the most sensitive diagnostic tool and should be performed promptly especially when thoracentesis fails to drain fluid or blood or when ultrasonography shows the absence of pleural effusion. In case of lobar torsion causing emphysema and me-
diastinal shift, as encountered in 2 infants (cases 5 and 7), differential diagnosis has to be made with congenital lobar emphysema (CLE) and pneumothorax: clinical history and eventually previous chest x-rays will help in differentiating between these conditions. However, despite various radiologic investigations, diagnosis remained uncertain until surgery in all pediatric patients. Maybe bronchoscopy could be of diagnostic value, as in adults, but it was never performed in affected children. Histologic examination was consistent with hemorragic necrosis and parenchymal infarction owing to vascular compromise in 6 children, whereas lobar emphysema produced by check-valve effect of the constricted bronchus with air trapping was present in 2 cases. This mechanism may account for spontaneous transient resolution of emphysema as observed in our latter case. In both infants, a 180° torsion involved the LUL. Once LT is detected, a conservative approach, namely, lung or lobe detorsion, may be attempted only when torsion is diagnosed within a few hours from its onset and in the presence of a moderate degree of vascular impairment7-9; however, simple lung detorsion performed in 1 child resulted in a nonfunctioning shrunken left lung, which was later removed.6 According to the literature and to our own experience, we believe that resection of the involved lobe or entire lung is the best curative option to lower any additional morbidity and mortality. Besides, if careful anatomic unfolding of the lobes with inflation under vision before chest closure is mandatory to avoid LT, we suggest that pulmonary lobe fixation should be accomplished to prevent further morbility in every child undergoing cardiothoracic surgery, in whom a complete pulmonary fissure and/or free long pedicle is detected.
REFERENCES 1. Parks R: Traumatic torsion of the lung. Radiology 67:582-583, 1952 2. Stratemeier EH, Barry JW: Torsion of the lung following thoracic trauma. Radiology 62:726-727, 1954 3. Daughtry DC: Traumatic torsion of the lung. N Engl J Med 258:385-388, 1957 4. Selmonosky CA, Flege JB Jr, Ehrenhaft JL: Torsion of the lobe of the lung due to blunt chest trauma. Ann Thorac Surg 4:166-170, 1967 5. Hislop A, Reid L: New pathological findings in emphysema in childhood: Overinflation of a normal lobe. Thorax 26:190-194, 1971 6. Fu J, Chen CL, Wu JY, et al: Lung torsion: Survival of a patient whose hemorragic infarcted lung remained in situ after torsion. J Thorac Cardiovasc Surg 99:1112-1114, 1990 7. Huang TY, Cho SR: Torsion of the lung without trauma. Diag Radiol 143:25-26, 1979 8. Kelly MV, Kyger ER, Miller WC: Postoperative lobar torsion and gangrene. Thorax 72:501-504, 1977 9. Chambers RF, Sweeney DF: Gangrenous sequestration of remaining lobe following lobectomy. Ann Thorac Surg 5:156-161, 1968
10. Oddi MA, Taugott RC, Will RJ, et al: Unrecognized intraoperative torsion of the lung. Surgery 89:390-393, 1981 11. Pintsein MZ, Winer-Muram H, Eastridge C, et al: Middle lobe torsion following right upper lobectomy. Radiology 155:580, 1985 12. Felson B: Lung torsion: Radiographic findings in nine cases. Radiology 162:631-638, 1987 13. Larsson S, Lepore V, Dernevik L, et al: Torsion of a lung lobe: Diagnosis and treatment. Thorac Cardiovasc Surg 36:281-283, 1988 14. Schamaun M: Postoperative pulmonary torsion: Report of a case and survey of the literature including spontaneous and posttraumatic torsion. Thorac Cardiovasc Surg 42:116-121, 1994 15. Munk PL, Vellet AD, Zwirewich C: Torsion of the upper lobe of the lung after surgery: Findings on pulmonary angiography. AJR 157:471-472, 1991 16. Chan MCK, Scott JM, Mercer CD, et al: Intraoperative wholelung torsion producing pulmonary venous infarction. Ann Thorac Surg 57:1330-1331, 1994 17. Kucich VA, Villareal JR, Schwartz DB: Left upper lobe torsion following lower lobe resection: Early recognition of a rare complication. Chest 95:1146-1147, 1989
POSTOPERATIVE PULMONARY TORSION
18. Livaudais W, Cavanaugh DG, Geer TM: Rapid postoperative thoracotomy for torsion of the left lower lobe: Case report. Milit Med 145:698-699, 1980 19. Mullin MJ, Zumbro GL, Fishback ME, et al: Pulmonary lobar gangrene complicating lobectomy. Ann Surg 175:62-66, 1972 20. Louis JR, Daffner RH: Torsion of the lung causing refractory hypoxemia. J Trauma 27:687-688, 1987
1723
21. Hislop A, Reid L: New pathological findings in emphysema of childhood. Overinflation of a normal lobe. Thorax 26:190-194, 1971 22. Wong PS, Goldstraw P: Pulmonary torsion: A questionnaire survey and a survey of the literature. Ann Thorac Surg 54:286-28, 1992 23. Cable DG, Deschamps C, Allen MS, et al: Lobar torsion after pulmonary resection: Presentation and outcome. J Thorac Cardiovasc Surg 122:1091-1093, 2001