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Azygos vein erosion: A potential complication of central venous access
Journal of Pediatric Surgery Case Reports 24 (2017) 1e4
Contents lists available at ScienceDirect
Journal of Pediatric Surgery Case Reports journal homepage: www.jpscasereports.com
Azygos vein erosion: A potential complication of central venous access David P. Mysona a, Randi L. Lassiter b, Kenneth C. Walters b, c, Walter L. Pipkin b, c, Robyn M. Hatley b, c, * a
Medical College of Georgia at Augusta University, 1120 15th St, Augusta, GA 30912, USA Department of Surgery, Medical College of Georgia at Augusta University, 1120 15th St, BI-4070, Augusta, GA 30912, USA c Section of Pediatric Surgery, Children's Hospital of Georgia, 1120 15th St, BAN-8216, Augusta, GA 30912, USA b
a r t i c l e i n f o
a b s t r a c t
Article history: Received 18 April 2017 Received in revised form 18 May 2017 Accepted 19 May 2017 Available online 22 May 2017
Central venous access is a common procedure that is performed for a variety of reasons. However, occasionally these lines can be misplaced at an improper anatomic location despite fluoroscopic guidance. Here we present a pediatric case in which a central venous port appeared correctly located on anteriorposterior (AP) fluoroscopic view. However, it was later discovered on lateral views that the catheter was placed in the azygos vein. The catheter eroded through the azygos vein and into the pleural space. This article highlights the importance of proper technique when placing central lines and discusses additional techniques and avenues of research in order to prevent this complication in the future. © 2017 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Keywords: Central venous access Complications Azygos vein
1. Introduction
2. Case report
Central venous catheter placement is a common procedure with over 5 million central venous catheters placed each year in the United States alone [1]. There are a number of indications for catheter placement, including delivery of medications, total parental nutrition, and intravenous fluids. Two of the most common anatomic veins used are the internal jugular and subclavian veins [2]. Both ultrasound and fluoroscopic guidance are often used to aide in proper positioning and visualization of catheter placement [2,3]. However, despite these innovations, over 15% of these catheters placed will result in a complication [1]. Potential complications are numerous and range from causing a pneumothorax or cannulation of an artery during the procedure to the development of a catheter infection many weeks later [1,3,4]. This report describes a case of a rare complication of central venous access: placement within in the azygos vein with subsequent erosion into the pleural space. This article also provides a discussion of placement technique, ways to further reduce complications, and considerations when complications arise.
A 4-year-old child with prune belly syndrome resulting in renal failure was referred to the pediatric surgery clinic for port placement. The indications for port placement included vascular access to administer medications, perform laboratory blood draws, and facilitate listing for renal transplant. At the time of the operation, ultrasound was used to visualize and confirm needle puncture of the right internal jugular vein. The port was then inserted using standard Seldinger technique. The port returned blood on aspiration and flushed easily. Placement was confirmed using fluoroscopy in the anterior-posterior (AP) direction (Fig. 1). Four weeks later, the child returned to the hospital with lethargy, upper respiratory symptoms, and urinary tract infection. Upon admission, the port was accessed and maintenance fluids were started at 45 ml/h. The following morning, the child developed increased respiratory distress. A two-view chest x-ray was obtained. The AP view demonstrated a large right pleural effusion and what appeared to be appropriate catheter placement (Fig. 2A). The lateral view clearly showed the catheter tracking posteriorly, indicating that the catheter was not in the superior vena cava (SVC) (Fig. 2B). Position within the azygos vein with erosion through the parietal pleura, resulting in delivery of maintenance fluids into the pleural space overnight was suspected. The port was aspirated with return of 500 ml of clear fluid. Interventional Radiology was consulted to reposition the catheter within the SVC. Placement was
* Corresponding author. Medical College of Georgia at Augusta University, Department of Surgery, Section of Pediatric Surgery, Children's Hospital of Georgia, 1120 15th Street, BAN-8216, Augusta, GA 30912, USA. E-mail addresses: [email protected] (D.P. Mysona), [email protected] (R.L. Lassiter), [email protected] (K.C. Walters), [email protected] (W.L. Pipkin), [email protected] (R.M. Hatley).
http://dx.doi.org/10.1016/j.epsc.2017.05.013 2213-5766/© 2017 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
2
D.P. Mysona et al. / Journal of Pediatric Surgery Case Reports 24 (2017) 1e4
Fig. 1. Fluoroscopy image from original port placement.
verified by a contrast venogram. Contrast injected into the SVC was shown to travel directly into the heart followed by the pulmonary circulation. There was no evidence of contrast extravasation or filling of accessory veins (Fig. 3A,B). The patient tolerated the procedure well. Post-procedure, Interventional Radiology recommended that the port not be accessed for 2e3 weeks. In two weeks, the patient was brought in for outpatient follow up. At this time, skin sutures placed during the port revision were removed. The patient has done well, and the port has since been accessed for blood draws without issue. 3. Discussion Despite the use of ultrasound and fluoroscopic guidance
techniques for these common procedures, the complication rates associated with central venous access remain high (>15%) [1,5]. The most common complications encountered during central venous access include thrombosis, anatomic misplacement, and mechanical complications [5]. Anatomic and mechanical complications include events such as pneumothorax, arterial puncture, or malposition. Malposition can refer to the catheter being placed at a variety of sites including the contralateral brachiocephalic, inferior vena cava, or rarely, the azygos vein [8,9]. Furthermore, certain complications tend to be associated with specific techniques of achieving access. For example, it has been reported that arterial puncture occurs more often with jugular access (6e9% of procedures) versus subclavian access (3e4% of procedures) [1,4]. However, internal jugular placement leads to fewer malposition events (5% of all placements) and fewer pneumothoraces (0.1% of all placements) compared to subclavian placement, which has an almost 9% malposition rate and a 1.5e3% rate of pneumothorax [1,6]. Despite multiple studies comparing complication rates between subclavian and internal jugular placed catheters, there is still much debate about which is superior [4,7]. In this case, access was achieved using the right internal jugular vein and malposition unfortunately ensued. Although the sites of improper catheter position are generally agreed upon, much debate exists about the best place for the catheter tip to prevent malposition and other complications [10,11]. The primary debate over catheter tip placement revolves around whether the tip should lie within the SVC or the cavoatrial junction where the SVC joins the right atrium [11]. The main concern of this positioning battle is that the tip of the catheter should not be allowed to migrate into the heart, as recommended by the Food and Drug Administration [10]. Several radiologic landmarks have been suggested in order to verify correct catheter tip position in the desired location. In the pediatric population, the carina or slightly below is a recommended landmark for correct placement [10,12]. However, this implies use of AP chest radiographs. This technique did not prevent catheter placement in the azygos vein in our case. The current literature provides minimal recommendations for preventing this complication. However, the Interventional Radiology Department at Medical College of Georgia provided an expert opinion suggesting that
Fig. 2. Chest radiographs obtained four weeks after port placement. A. Anterior-posterior view. B. Lateral view of catheter projecting too far posterior to be within the superior vena cava.
D.P. Mysona et al. / Journal of Pediatric Surgery Case Reports 24 (2017) 1e4
3
Fig. 3. Fluoroscopy images from endovascular port repositioning. A. Port position verified with venography demonstrating catheter tubing in line with contrast injected into the superior vena cava and traveling to the heart and pulmonary vasculature. B. Anterior-posterior view of final port position.
advancing the guide wire all the way to the inferior vena cava would ensure that the wire did not travel down any accessory path. In theory, this would lead to proper catheter placement, but the efficacy of this technique has not been validated in the literature. Central venous catheter malposition in the azygos vein is a very rare occurrence [9]. Due to the azygos being a smaller vein, it is much more susceptible to be damaged by a catheter and can erode [13]. This is of significant concern because vascular erosion is associated with significant morbidity and mortality [14]. Furthermore, it is well-established that AP chest x-ray imaging is poor means of detecting central venous catheter placement within the azygos venous system [15]. This leads to a dangerous predicament because, as shown in this case, a chest x-ray in AP direction is often used first line when a patient presents with apparent cardiopulmonary issues. However, if the patient symptoms are due to catheter malposition it may not necessarily be obvious with an AP chest x-ray, and the diagnosis may be missed for an extended period, resulting in harm to the patient. We reviewed the literature for any studies performing a riskbenefit or cost-benefit analysis of doing a lateral chest x-ray in conjunction with an AP x-ray to evaluate central venous catheter placement. The literature search did not yield any studies evaluating these questions. The risk-benefit question is an especially important in the pediatric population where it is imperative to minimize radiation exposure as much as possible. Because of the rarity of catheter malposition, a prudent compromise may be to obtain both AP and lateral chest x-ray views in any patient presenting with acute cardiopulmonary symptoms within 4e6 weeks of central venous catheter placement. This could prevent missing the diagnosis of malposition with vascular erosion. It would also have the benefit of minimizing radiation exposure in the vast majority of cases in which the catheter is properly positioned. 4. Conclusion This case provides an interesting presentation of a right internal
jugular vein port placed in the azygos vein with subsequent erosion into the pleural space. In this case, improper positioning of catheter was recognized based on a lateral chest x-ray after an AP x-ray revealed a large pleural effusion but no indication of improper placement. If this complication had not been recognized early, it could have had severe consequences. Fortunately, the catheter was repositioned by Interventional radiology into the SVC. It is well known that the smaller veins such as the azygos have thinner walls and thus are predisposed to catheter irritation and erosion. These events can have significant consequences. To our knowledge, no studies have evaluated the use of lateral chest radiographs to verify proper central venous catheter placement. Further studies may need to evaluate a risk-benefit analysis of a lateral chest x-ray in addition to an AP oriented x-ray to confirm proper catheter placement and prevent this complication from happening in the future. Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Conflicts of interest None. Acknowledgements The authors would like to thank the Augusta University Division of Vascular and Interventional Radiology for their support in management of the patient and contribution of images to this manuscript. References [1] McGee DC, Gould MK. Preventing complications of central venous
4
[2]
[3]
[4]
[5]
[6]
[7]
[8]
D.P. Mysona et al. / Journal of Pediatric Surgery Case Reports 24 (2017) 1e4 catheterization. N Engl J Med 2003;348(12):1123e33. http://dx.doi.org/ 10.1056/NEJMra011883. Hind D, Calvert N, McWilliams R, Davidson A, Paisley S, Beverley C, et al. Ultrasonic locating devices for central venous cannulation: meta-analysis. BMJ 2003;327(7411):361. http://dx.doi.org/10.1136/bmj.327.7411.361. Yildizeli B, Lacin T, Batirel HF, Yuksel M. Complications and management of long-term central venous access catheters and ports. J Vasc Access 2004;5(4): 174e8. Ruesch S, Walder B, Tramer MR. Complications of central venous catheters: internal jugular versus subclavian accessea systematic review. Crit Care Med 2002;30(2):454e60. Bruzoni M, Slater BJ, Wall J, St Peter SD, Dutta S. A prospective randomized trial of ultrasound- vs landmark-guided central venous access in the pediatric population. J Am Coll Surg 2013;216(5):939e43. http://dx.doi.org/10.1016/ j.jamcollsurg.2013.01.054. Graham AS, Ozment C, Tegtmeyer K, Lai S, Braner DA. Videos in clinical medicine. Central venous catheterization. N Engl J Med 2007;356(21):e21. http://dx.doi.org/10.1056/NEJMvcm055053. Pikwer A, Baath L, Davidson B, Perstoft I, Akeson J. The incidence and risk of central venous catheter malpositioning: a prospective cohort study in 1619 patients. Anaesth Intensive Care 2008;36(1):30e7. Nayeemuddin M, Pherwani AD, Asquith JR. Imaging and management of complications of central venous catheters. Clin Radiol 2013;68(5):529e44. http://dx.doi.org/10.1016/j.crad.2012.10.013.
[9] Bankier AA, Mallek R, Wiesmayr MN, Fleischmann D, Kranz A, Kontrus M, et al. Azygos arch cannulation by central venous catheters: radiographic detection of malposition and subsequent complications. J Thorac Imaging 1997;12(1): 64e9. [10] Perin G, Scarpa MG. Defining central venous line position in children: tips for the tip. J Vasc Access 2015;16(2):77e86. http://dx.doi.org/10.5301/ jva.5000285. [11] Vesely TM. Central venous catheter tip position: a continuing controversy. J Vasc Interv Radiol 2003;14(5):527e34. [12] Baskin KM, Jimenez RM, Cahill AM, Jawad AF, Towbin RB. Cavoatrial junction and central venous anatomy: implications for central venous access tip position. J Vasc Interv Radiol 2008;19(3):359e65. http://dx.doi.org/10.1016/ j.jvir.2007.09.005. [13] Gish J, Wright T, Gadepalli S, Jarboe M. Avoiding postoperative malposition of upper body tunneled central venous catheters in children: evaluating technique and depth of placement. J Pediatr Surg 2016;51(8):1336e40. http:// dx.doi.org/10.1016/j.jpedsurg.2016.01.010. [14] Roldan CJ, Paniagua L. Central venous catheter intravascular malpositioning: causes, prevention, diagnosis, and correction. West J Emerg Med 2015;16(5): 658e64. http://dx.doi.org/10.5811/westjem.2015.7.26248. [15] Gibson F, Bodenham A. Misplaced central venous catheters: applied anatomy and practical management. Br J Anaesth 2013;110(3):333e46. http:// dx.doi.org/10.1093/bja/aes497.
Contents lists available at ScienceDirect
Journal of Pediatric Surgery Case Reports journal homepage: www.jpscasereports.com
Azygos vein erosion: A potential complication of central venous access David P. Mysona a, Randi L. Lassiter b, Kenneth C. Walters b, c, Walter L. Pipkin b, c, Robyn M. Hatley b, c, * a
Medical College of Georgia at Augusta University, 1120 15th St, Augusta, GA 30912, USA Department of Surgery, Medical College of Georgia at Augusta University, 1120 15th St, BI-4070, Augusta, GA 30912, USA c Section of Pediatric Surgery, Children's Hospital of Georgia, 1120 15th St, BAN-8216, Augusta, GA 30912, USA b
a r t i c l e i n f o
a b s t r a c t
Article history: Received 18 April 2017 Received in revised form 18 May 2017 Accepted 19 May 2017 Available online 22 May 2017
Central venous access is a common procedure that is performed for a variety of reasons. However, occasionally these lines can be misplaced at an improper anatomic location despite fluoroscopic guidance. Here we present a pediatric case in which a central venous port appeared correctly located on anteriorposterior (AP) fluoroscopic view. However, it was later discovered on lateral views that the catheter was placed in the azygos vein. The catheter eroded through the azygos vein and into the pleural space. This article highlights the importance of proper technique when placing central lines and discusses additional techniques and avenues of research in order to prevent this complication in the future. © 2017 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Keywords: Central venous access Complications Azygos vein
1. Introduction
2. Case report
Central venous catheter placement is a common procedure with over 5 million central venous catheters placed each year in the United States alone [1]. There are a number of indications for catheter placement, including delivery of medications, total parental nutrition, and intravenous fluids. Two of the most common anatomic veins used are the internal jugular and subclavian veins [2]. Both ultrasound and fluoroscopic guidance are often used to aide in proper positioning and visualization of catheter placement [2,3]. However, despite these innovations, over 15% of these catheters placed will result in a complication [1]. Potential complications are numerous and range from causing a pneumothorax or cannulation of an artery during the procedure to the development of a catheter infection many weeks later [1,3,4]. This report describes a case of a rare complication of central venous access: placement within in the azygos vein with subsequent erosion into the pleural space. This article also provides a discussion of placement technique, ways to further reduce complications, and considerations when complications arise.
A 4-year-old child with prune belly syndrome resulting in renal failure was referred to the pediatric surgery clinic for port placement. The indications for port placement included vascular access to administer medications, perform laboratory blood draws, and facilitate listing for renal transplant. At the time of the operation, ultrasound was used to visualize and confirm needle puncture of the right internal jugular vein. The port was then inserted using standard Seldinger technique. The port returned blood on aspiration and flushed easily. Placement was confirmed using fluoroscopy in the anterior-posterior (AP) direction (Fig. 1). Four weeks later, the child returned to the hospital with lethargy, upper respiratory symptoms, and urinary tract infection. Upon admission, the port was accessed and maintenance fluids were started at 45 ml/h. The following morning, the child developed increased respiratory distress. A two-view chest x-ray was obtained. The AP view demonstrated a large right pleural effusion and what appeared to be appropriate catheter placement (Fig. 2A). The lateral view clearly showed the catheter tracking posteriorly, indicating that the catheter was not in the superior vena cava (SVC) (Fig. 2B). Position within the azygos vein with erosion through the parietal pleura, resulting in delivery of maintenance fluids into the pleural space overnight was suspected. The port was aspirated with return of 500 ml of clear fluid. Interventional Radiology was consulted to reposition the catheter within the SVC. Placement was
* Corresponding author. Medical College of Georgia at Augusta University, Department of Surgery, Section of Pediatric Surgery, Children's Hospital of Georgia, 1120 15th Street, BAN-8216, Augusta, GA 30912, USA. E-mail addresses: [email protected] (D.P. Mysona), [email protected] (R.L. Lassiter), [email protected] (K.C. Walters), [email protected] (W.L. Pipkin), [email protected] (R.M. Hatley).
http://dx.doi.org/10.1016/j.epsc.2017.05.013 2213-5766/© 2017 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
2
D.P. Mysona et al. / Journal of Pediatric Surgery Case Reports 24 (2017) 1e4
Fig. 1. Fluoroscopy image from original port placement.
verified by a contrast venogram. Contrast injected into the SVC was shown to travel directly into the heart followed by the pulmonary circulation. There was no evidence of contrast extravasation or filling of accessory veins (Fig. 3A,B). The patient tolerated the procedure well. Post-procedure, Interventional Radiology recommended that the port not be accessed for 2e3 weeks. In two weeks, the patient was brought in for outpatient follow up. At this time, skin sutures placed during the port revision were removed. The patient has done well, and the port has since been accessed for blood draws without issue. 3. Discussion Despite the use of ultrasound and fluoroscopic guidance
techniques for these common procedures, the complication rates associated with central venous access remain high (>15%) [1,5]. The most common complications encountered during central venous access include thrombosis, anatomic misplacement, and mechanical complications [5]. Anatomic and mechanical complications include events such as pneumothorax, arterial puncture, or malposition. Malposition can refer to the catheter being placed at a variety of sites including the contralateral brachiocephalic, inferior vena cava, or rarely, the azygos vein [8,9]. Furthermore, certain complications tend to be associated with specific techniques of achieving access. For example, it has been reported that arterial puncture occurs more often with jugular access (6e9% of procedures) versus subclavian access (3e4% of procedures) [1,4]. However, internal jugular placement leads to fewer malposition events (5% of all placements) and fewer pneumothoraces (0.1% of all placements) compared to subclavian placement, which has an almost 9% malposition rate and a 1.5e3% rate of pneumothorax [1,6]. Despite multiple studies comparing complication rates between subclavian and internal jugular placed catheters, there is still much debate about which is superior [4,7]. In this case, access was achieved using the right internal jugular vein and malposition unfortunately ensued. Although the sites of improper catheter position are generally agreed upon, much debate exists about the best place for the catheter tip to prevent malposition and other complications [10,11]. The primary debate over catheter tip placement revolves around whether the tip should lie within the SVC or the cavoatrial junction where the SVC joins the right atrium [11]. The main concern of this positioning battle is that the tip of the catheter should not be allowed to migrate into the heart, as recommended by the Food and Drug Administration [10]. Several radiologic landmarks have been suggested in order to verify correct catheter tip position in the desired location. In the pediatric population, the carina or slightly below is a recommended landmark for correct placement [10,12]. However, this implies use of AP chest radiographs. This technique did not prevent catheter placement in the azygos vein in our case. The current literature provides minimal recommendations for preventing this complication. However, the Interventional Radiology Department at Medical College of Georgia provided an expert opinion suggesting that
Fig. 2. Chest radiographs obtained four weeks after port placement. A. Anterior-posterior view. B. Lateral view of catheter projecting too far posterior to be within the superior vena cava.
D.P. Mysona et al. / Journal of Pediatric Surgery Case Reports 24 (2017) 1e4
3
Fig. 3. Fluoroscopy images from endovascular port repositioning. A. Port position verified with venography demonstrating catheter tubing in line with contrast injected into the superior vena cava and traveling to the heart and pulmonary vasculature. B. Anterior-posterior view of final port position.
advancing the guide wire all the way to the inferior vena cava would ensure that the wire did not travel down any accessory path. In theory, this would lead to proper catheter placement, but the efficacy of this technique has not been validated in the literature. Central venous catheter malposition in the azygos vein is a very rare occurrence [9]. Due to the azygos being a smaller vein, it is much more susceptible to be damaged by a catheter and can erode [13]. This is of significant concern because vascular erosion is associated with significant morbidity and mortality [14]. Furthermore, it is well-established that AP chest x-ray imaging is poor means of detecting central venous catheter placement within the azygos venous system [15]. This leads to a dangerous predicament because, as shown in this case, a chest x-ray in AP direction is often used first line when a patient presents with apparent cardiopulmonary issues. However, if the patient symptoms are due to catheter malposition it may not necessarily be obvious with an AP chest x-ray, and the diagnosis may be missed for an extended period, resulting in harm to the patient. We reviewed the literature for any studies performing a riskbenefit or cost-benefit analysis of doing a lateral chest x-ray in conjunction with an AP x-ray to evaluate central venous catheter placement. The literature search did not yield any studies evaluating these questions. The risk-benefit question is an especially important in the pediatric population where it is imperative to minimize radiation exposure as much as possible. Because of the rarity of catheter malposition, a prudent compromise may be to obtain both AP and lateral chest x-ray views in any patient presenting with acute cardiopulmonary symptoms within 4e6 weeks of central venous catheter placement. This could prevent missing the diagnosis of malposition with vascular erosion. It would also have the benefit of minimizing radiation exposure in the vast majority of cases in which the catheter is properly positioned. 4. Conclusion This case provides an interesting presentation of a right internal
jugular vein port placed in the azygos vein with subsequent erosion into the pleural space. In this case, improper positioning of catheter was recognized based on a lateral chest x-ray after an AP x-ray revealed a large pleural effusion but no indication of improper placement. If this complication had not been recognized early, it could have had severe consequences. Fortunately, the catheter was repositioned by Interventional radiology into the SVC. It is well known that the smaller veins such as the azygos have thinner walls and thus are predisposed to catheter irritation and erosion. These events can have significant consequences. To our knowledge, no studies have evaluated the use of lateral chest radiographs to verify proper central venous catheter placement. Further studies may need to evaluate a risk-benefit analysis of a lateral chest x-ray in addition to an AP oriented x-ray to confirm proper catheter placement and prevent this complication from happening in the future. Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Conflicts of interest None. Acknowledgements The authors would like to thank the Augusta University Division of Vascular and Interventional Radiology for their support in management of the patient and contribution of images to this manuscript. References [1] McGee DC, Gould MK. Preventing complications of central venous
4
[2]
[3]
[4]
[5]
[6]
[7]
[8]
D.P. Mysona et al. / Journal of Pediatric Surgery Case Reports 24 (2017) 1e4 catheterization. N Engl J Med 2003;348(12):1123e33. http://dx.doi.org/ 10.1056/NEJMra011883. Hind D, Calvert N, McWilliams R, Davidson A, Paisley S, Beverley C, et al. Ultrasonic locating devices for central venous cannulation: meta-analysis. BMJ 2003;327(7411):361. http://dx.doi.org/10.1136/bmj.327.7411.361. Yildizeli B, Lacin T, Batirel HF, Yuksel M. Complications and management of long-term central venous access catheters and ports. J Vasc Access 2004;5(4): 174e8. Ruesch S, Walder B, Tramer MR. Complications of central venous catheters: internal jugular versus subclavian accessea systematic review. Crit Care Med 2002;30(2):454e60. Bruzoni M, Slater BJ, Wall J, St Peter SD, Dutta S. A prospective randomized trial of ultrasound- vs landmark-guided central venous access in the pediatric population. J Am Coll Surg 2013;216(5):939e43. http://dx.doi.org/10.1016/ j.jamcollsurg.2013.01.054. Graham AS, Ozment C, Tegtmeyer K, Lai S, Braner DA. Videos in clinical medicine. Central venous catheterization. N Engl J Med 2007;356(21):e21. http://dx.doi.org/10.1056/NEJMvcm055053. Pikwer A, Baath L, Davidson B, Perstoft I, Akeson J. The incidence and risk of central venous catheter malpositioning: a prospective cohort study in 1619 patients. Anaesth Intensive Care 2008;36(1):30e7. Nayeemuddin M, Pherwani AD, Asquith JR. Imaging and management of complications of central venous catheters. Clin Radiol 2013;68(5):529e44. http://dx.doi.org/10.1016/j.crad.2012.10.013.
[9] Bankier AA, Mallek R, Wiesmayr MN, Fleischmann D, Kranz A, Kontrus M, et al. Azygos arch cannulation by central venous catheters: radiographic detection of malposition and subsequent complications. J Thorac Imaging 1997;12(1): 64e9. [10] Perin G, Scarpa MG. Defining central venous line position in children: tips for the tip. J Vasc Access 2015;16(2):77e86. http://dx.doi.org/10.5301/ jva.5000285. [11] Vesely TM. Central venous catheter tip position: a continuing controversy. J Vasc Interv Radiol 2003;14(5):527e34. [12] Baskin KM, Jimenez RM, Cahill AM, Jawad AF, Towbin RB. Cavoatrial junction and central venous anatomy: implications for central venous access tip position. J Vasc Interv Radiol 2008;19(3):359e65. http://dx.doi.org/10.1016/ j.jvir.2007.09.005. [13] Gish J, Wright T, Gadepalli S, Jarboe M. Avoiding postoperative malposition of upper body tunneled central venous catheters in children: evaluating technique and depth of placement. J Pediatr Surg 2016;51(8):1336e40. http:// dx.doi.org/10.1016/j.jpedsurg.2016.01.010. [14] Roldan CJ, Paniagua L. Central venous catheter intravascular malpositioning: causes, prevention, diagnosis, and correction. West J Emerg Med 2015;16(5): 658e64. http://dx.doi.org/10.5811/westjem.2015.7.26248. [15] Gibson F, Bodenham A. Misplaced central venous catheters: applied anatomy and practical management. Br J Anaesth 2013;110(3):333e46. http:// dx.doi.org/10.1093/bja/aes497.