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Lung injury and pneumothorax after defibrillation as demonstrated with computed tomography
American Journal of Emergency Medicine 31 (2013) 1003.e1–1003.e3
Contents lists available at SciVerse ScienceDirect
American Journal of Emergency Medicine journal homepage: www.elsevier.com/locate/ajem
Case Report
Lung injury and pneumothorax after defibrillation as demonstrated with computed tomography Abstract Many patients present for emergency services after electric injuries or require defibrillation during emergency services. Although the defibrillation process is safe, skin burns and myocardial injuries are reported after defibrillation procedures. There are limited data about the complications of defibrillation. In the case reported here, a lung injury and a small pneumothorax were observed after defibrillation. To the best of our knowledge, this is the first reported case in which computed tomography is used to demonstrate that a trace of electric current passed through the lung. Computed tomography may be an excellent diagnostic modality to demonstrate the severity and extent of electric injuries to the lung. Defibrillation is a widely used, life-saving procedure with a relatively low complication rate [1]. However, potential complications of defibrillation are well documented [2]. The electric shock used in defibrillation is enough to cause tissue burns. In addition, it has been reported that defibrillation can cause significant myocardial damage [3]. It has also been reported that sufficiently strong defibrillation shocks can cause temporary or permanent damage to the heart, although this effect has not yet been demonstrated with imaging modalities [4]. To the best of our knowledge, no complication associated with the lungs other than pulmonary edema after defibrillation has been reported in the literature. It is believed that
Fig. 1. Axial plane CT image: branching hypolucent lines (lighting pattern) in the middle lobe and lingular segment (white arrows). Also note the small pneumothorax in the left hemithorax (black arrow). 0735-6757/$ – see front matter © 2013 Elsevier Inc. All rights reserved.
pulmonary edema is due to left ventricular dysfunction or transient left atrial standstill, both of which are unrelated to damage due to electricity [5]. We present a case with a lung parenchyma injury and pneumothorax after defibrillation. A 26-year-old male patient developed a sudden loss of consciousness following alcohol intake. Cardiopulmonary resuscitation was performed for 50 minutes due to asystole. When asystole was converted into ventricle fibrillation, defibrillation was performed. The patient was followed up in the intensive care unit. The next day, a chest computed tomographic (CT) examination revealed bilateral consolidation and ground glass attenuation consistent with pulmonary edema. In the middle lobe and lingular segment, there were hypolucent lines branching toward the heart (Fig. 1). These lines began at the application locations of the apical and sternal defibrillation paddles. In addition, a small pneumothorax was noted in the left hemithorax. Cardiac CT examination was performed 5 days later to evaluate the coronary arteries and other possible cardiac pathologies. This examination also revealed the same hypolucent lines in both lungs, which were almost unchanged. The pneumothorax also observed in the right hemithorax, mostly around the heart, which was the target organ of the defibrillation (Fig. 2). A minimum intensity projection image in the oblique reformatted plane shows the trace and pattern of the hypolucent lines more clearly, including their resemblance to lightening (Fig. 3). The coronary arteries were unremarkable. The patient had undergone no trauma, had no previous pneumothorax history, and had no air cyst or emphysema throughout the lung that may be potential causes for the pneumothorax. The first reported defibrillation of an exposed human heart was performed by Claude Beck, a cardiothoracic surgeon at Western Reserve University/University Hospitals of Cleveland, Ohio, in 1947. Since then, defibrillation has been performed safely with relatively low complication rates [6]. Although no pneumothorax is generally reported after defibrillation procedures, pneumothorax has been reported after accidental electrocution injuries [7,8]. In addition, an electrical burn of the lung was reported after high-voltage electrical trauma [9]. In these accidental scenarios, the electric voltage and current were much higher than that used in defibrillation. However, defibrillators use shocks of 200 to 360 J, which is enough to cause tissue damage. After defibrillation, skin burns and myocardial injuries are sometimes reported [10]. These tissue injuries are minor and mostly self-healing. In the case reported here, CT revealed the trace of electric current that began at the anterior chest wall (entrance point) with a single line and branched toward the heart. This pattern is typical for electrical current conduction in a low-conductive environment, which was air in this situation. These hypolucent lines are traces of electric current that passed through the lung. The pattern is similar to naturally occurring
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T. Gümüş et al. / American Journal of Emergency Medicine 31 (2013) 1003.e1–1003.e3
Fig. 3. Oblique axial plane CT image (minimum intensity projection): branching pattern of hypolucent lines is shown more clearly (arrow). Note that the line is single anteriorly (probable entrance point) and branches while proceeding posteriorly and medially.
Fig. 2. Axial cardiac CT images performed 5 days later than the first CT: hypolucent lines toward the heart (arrows) (A); the more cranial image reveals a small pneumothorax around heart (arrow) (B).
lightning, where electricity travels in air. In this case, the electric current damaged the lung parenchyma along its course, which caused leakage of air. The leaked air, which followed the path of the electric current, entered the pleural space, where it caused the pneumothorax. Reported cases of pneumothorax after high-voltage electric injury were based on x-ray images [7,8]. If these cases used CT, the trace of the electric current might have been observed. These hypolucent traces are only observed in the lung over which the defibrillation paddles are placed. Streak artifacts may cause hypolucent lines on CT images. In the case reported here, these hypolucent lines branch, which is atypical for streak artifacts. There were no metal objects, which commonly causes streak artifacts, on or in the patient. Furthermore, an electrocardiogram-gated cardiac CT examination, which was performed 5 days after the initial lung CT examination, showed the same hypolucent traces in exactly the same location with a further increase in pneumothorax findings. These data also support the theory of a possible microdissection of the lung and subsequent air leakage, which increased with time. Over 5 days, the pneumothorax and lung injury were self-limiting, and no further
Fig. 4. X-ray image reveals no pneumothorax or parenchymal injury observed in CT images.
treatment such as a chest tube was needed. This may explain why we are not familiar with these findings despite the high numbers of routinely performed defibrillation procedures. In the days following defibrillation, many patients undergo x-ray examination. However, it is almost impossible to observe such a small pneumothorax with x-ray images. In the case reported here, we obtained x-ray images that were performed 1 day before the second CT (Fig. 4). In those images, the pneumothorax is not visible. To determine the frequency of and possible factors that can cause this lightning pattern after defibrillation, retrospective and prospective studies must be conducted.
Terman Gümüş MD American Hospital Department of Radiology Güzelbahçe sokak No:20 Nişantaşı, 34365 Istanbul, Turkey E-mail address: [email protected]
T. Gümüş et al. / American Journal of Emergency Medicine 31 (2013) 1003.e1–1003.e3
Düzgün Yıldırım MD Centermed Advanced Imaging Center Department of Radiology Nişantaşı, Istanbul, Turkey Gökhan Uçar MD American Hospital Department of Radiology Güzelbahçe sokak No:20 Nişantaşı, 34365 Istanbul, Turkey http://dx.doi.org/10.1016/j.ajem.2013.02.018 References [1] Lake CL, Sellers TD, Nolan SP, Crosby IK, Wellons HA, Crampton RS. Low-energy defibrillation: safe and effective. Am J Emerg Med 1985;3(2):104–7.
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[2] Sucu M, Davutoglu V, Ozer O. Electrical cardioversion. Ann Saudi Med 2009;29(3): 201–6. [3] Jones JL. Waveforms for implantable cardioverter defibrillators (ICDs) and transchest defibrillation. In: Tacker WA, editor. Defibrillation of the heart. St. Louis: Mosby-Year Book; 1994. p. 46–81. [4] Walcott GP, Killingsworth CR, Ideker RE. Do clinically relevant transthoracic defibrillation energies cause myocardial damage and dysfunction? Resuscitation 2003;59(1):59–70. [5] Lindsay J. Pulmonary edema following cardioversion. Am Heart J 1967;74:434. [6] Cakulev I, Efimov IR, Albert LW. Cardioversion past, present, and future. MD Circulation 2009;120:1623–32. [7] Ceber M, Ozturk C, Baghaki S, Cınar C. Pneumothorax due to electrical burn injury. Emerg Med J 2007;24(5):371–2. [8] Khan AH, Siddiqui RJ. Pneumothorax due to electrical burn. Indian J Chest Dis Allied Sci 1998;40:291–3. [9] Masanès MJ, Gourbière E, Prudent J, Lioret N, Febvre M, Prévot S, et al. A high voltage electrical burn of lung parenchyma. Burns 2000;26(7):659–63. [10] Ambler JJ, Sado DM, Zideman DA, Deakin CD. The incidence and severity of cutaneous burns following external DC cardioversion. Resuscitation 2004;61: 281–8.
Contents lists available at SciVerse ScienceDirect
American Journal of Emergency Medicine journal homepage: www.elsevier.com/locate/ajem
Case Report
Lung injury and pneumothorax after defibrillation as demonstrated with computed tomography Abstract Many patients present for emergency services after electric injuries or require defibrillation during emergency services. Although the defibrillation process is safe, skin burns and myocardial injuries are reported after defibrillation procedures. There are limited data about the complications of defibrillation. In the case reported here, a lung injury and a small pneumothorax were observed after defibrillation. To the best of our knowledge, this is the first reported case in which computed tomography is used to demonstrate that a trace of electric current passed through the lung. Computed tomography may be an excellent diagnostic modality to demonstrate the severity and extent of electric injuries to the lung. Defibrillation is a widely used, life-saving procedure with a relatively low complication rate [1]. However, potential complications of defibrillation are well documented [2]. The electric shock used in defibrillation is enough to cause tissue burns. In addition, it has been reported that defibrillation can cause significant myocardial damage [3]. It has also been reported that sufficiently strong defibrillation shocks can cause temporary or permanent damage to the heart, although this effect has not yet been demonstrated with imaging modalities [4]. To the best of our knowledge, no complication associated with the lungs other than pulmonary edema after defibrillation has been reported in the literature. It is believed that
Fig. 1. Axial plane CT image: branching hypolucent lines (lighting pattern) in the middle lobe and lingular segment (white arrows). Also note the small pneumothorax in the left hemithorax (black arrow). 0735-6757/$ – see front matter © 2013 Elsevier Inc. All rights reserved.
pulmonary edema is due to left ventricular dysfunction or transient left atrial standstill, both of which are unrelated to damage due to electricity [5]. We present a case with a lung parenchyma injury and pneumothorax after defibrillation. A 26-year-old male patient developed a sudden loss of consciousness following alcohol intake. Cardiopulmonary resuscitation was performed for 50 minutes due to asystole. When asystole was converted into ventricle fibrillation, defibrillation was performed. The patient was followed up in the intensive care unit. The next day, a chest computed tomographic (CT) examination revealed bilateral consolidation and ground glass attenuation consistent with pulmonary edema. In the middle lobe and lingular segment, there were hypolucent lines branching toward the heart (Fig. 1). These lines began at the application locations of the apical and sternal defibrillation paddles. In addition, a small pneumothorax was noted in the left hemithorax. Cardiac CT examination was performed 5 days later to evaluate the coronary arteries and other possible cardiac pathologies. This examination also revealed the same hypolucent lines in both lungs, which were almost unchanged. The pneumothorax also observed in the right hemithorax, mostly around the heart, which was the target organ of the defibrillation (Fig. 2). A minimum intensity projection image in the oblique reformatted plane shows the trace and pattern of the hypolucent lines more clearly, including their resemblance to lightening (Fig. 3). The coronary arteries were unremarkable. The patient had undergone no trauma, had no previous pneumothorax history, and had no air cyst or emphysema throughout the lung that may be potential causes for the pneumothorax. The first reported defibrillation of an exposed human heart was performed by Claude Beck, a cardiothoracic surgeon at Western Reserve University/University Hospitals of Cleveland, Ohio, in 1947. Since then, defibrillation has been performed safely with relatively low complication rates [6]. Although no pneumothorax is generally reported after defibrillation procedures, pneumothorax has been reported after accidental electrocution injuries [7,8]. In addition, an electrical burn of the lung was reported after high-voltage electrical trauma [9]. In these accidental scenarios, the electric voltage and current were much higher than that used in defibrillation. However, defibrillators use shocks of 200 to 360 J, which is enough to cause tissue damage. After defibrillation, skin burns and myocardial injuries are sometimes reported [10]. These tissue injuries are minor and mostly self-healing. In the case reported here, CT revealed the trace of electric current that began at the anterior chest wall (entrance point) with a single line and branched toward the heart. This pattern is typical for electrical current conduction in a low-conductive environment, which was air in this situation. These hypolucent lines are traces of electric current that passed through the lung. The pattern is similar to naturally occurring
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T. Gümüş et al. / American Journal of Emergency Medicine 31 (2013) 1003.e1–1003.e3
Fig. 3. Oblique axial plane CT image (minimum intensity projection): branching pattern of hypolucent lines is shown more clearly (arrow). Note that the line is single anteriorly (probable entrance point) and branches while proceeding posteriorly and medially.
Fig. 2. Axial cardiac CT images performed 5 days later than the first CT: hypolucent lines toward the heart (arrows) (A); the more cranial image reveals a small pneumothorax around heart (arrow) (B).
lightning, where electricity travels in air. In this case, the electric current damaged the lung parenchyma along its course, which caused leakage of air. The leaked air, which followed the path of the electric current, entered the pleural space, where it caused the pneumothorax. Reported cases of pneumothorax after high-voltage electric injury were based on x-ray images [7,8]. If these cases used CT, the trace of the electric current might have been observed. These hypolucent traces are only observed in the lung over which the defibrillation paddles are placed. Streak artifacts may cause hypolucent lines on CT images. In the case reported here, these hypolucent lines branch, which is atypical for streak artifacts. There were no metal objects, which commonly causes streak artifacts, on or in the patient. Furthermore, an electrocardiogram-gated cardiac CT examination, which was performed 5 days after the initial lung CT examination, showed the same hypolucent traces in exactly the same location with a further increase in pneumothorax findings. These data also support the theory of a possible microdissection of the lung and subsequent air leakage, which increased with time. Over 5 days, the pneumothorax and lung injury were self-limiting, and no further
Fig. 4. X-ray image reveals no pneumothorax or parenchymal injury observed in CT images.
treatment such as a chest tube was needed. This may explain why we are not familiar with these findings despite the high numbers of routinely performed defibrillation procedures. In the days following defibrillation, many patients undergo x-ray examination. However, it is almost impossible to observe such a small pneumothorax with x-ray images. In the case reported here, we obtained x-ray images that were performed 1 day before the second CT (Fig. 4). In those images, the pneumothorax is not visible. To determine the frequency of and possible factors that can cause this lightning pattern after defibrillation, retrospective and prospective studies must be conducted.
Terman Gümüş MD American Hospital Department of Radiology Güzelbahçe sokak No:20 Nişantaşı, 34365 Istanbul, Turkey E-mail address: [email protected]
T. Gümüş et al. / American Journal of Emergency Medicine 31 (2013) 1003.e1–1003.e3
Düzgün Yıldırım MD Centermed Advanced Imaging Center Department of Radiology Nişantaşı, Istanbul, Turkey Gökhan Uçar MD American Hospital Department of Radiology Güzelbahçe sokak No:20 Nişantaşı, 34365 Istanbul, Turkey http://dx.doi.org/10.1016/j.ajem.2013.02.018 References [1] Lake CL, Sellers TD, Nolan SP, Crosby IK, Wellons HA, Crampton RS. Low-energy defibrillation: safe and effective. Am J Emerg Med 1985;3(2):104–7.
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[2] Sucu M, Davutoglu V, Ozer O. Electrical cardioversion. Ann Saudi Med 2009;29(3): 201–6. [3] Jones JL. Waveforms for implantable cardioverter defibrillators (ICDs) and transchest defibrillation. In: Tacker WA, editor. Defibrillation of the heart. St. Louis: Mosby-Year Book; 1994. p. 46–81. [4] Walcott GP, Killingsworth CR, Ideker RE. Do clinically relevant transthoracic defibrillation energies cause myocardial damage and dysfunction? Resuscitation 2003;59(1):59–70. [5] Lindsay J. Pulmonary edema following cardioversion. Am Heart J 1967;74:434. [6] Cakulev I, Efimov IR, Albert LW. Cardioversion past, present, and future. MD Circulation 2009;120:1623–32. [7] Ceber M, Ozturk C, Baghaki S, Cınar C. Pneumothorax due to electrical burn injury. Emerg Med J 2007;24(5):371–2. [8] Khan AH, Siddiqui RJ. Pneumothorax due to electrical burn. Indian J Chest Dis Allied Sci 1998;40:291–3. [9] Masanès MJ, Gourbière E, Prudent J, Lioret N, Febvre M, Prévot S, et al. A high voltage electrical burn of lung parenchyma. Burns 2000;26(7):659–63. [10] Ambler JJ, Sado DM, Zideman DA, Deakin CD. The incidence and severity of cutaneous burns following external DC cardioversion. Resuscitation 2004;61: 281–8.