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Bi-caval dual lumen venovenous extracorporeal membrane oxygenation and high-frequency percussive ventilatory support for postintubation tracheal injury and acute respiratory distress syndrome
Journal of Pediatric Surgery (2011) 46, E11–E15
www.elsevier.com/locate/jpedsurg
Bi-caval dual lumen venovenous extracorporeal membrane oxygenation and high-frequency percussive ventilatory support for postintubation tracheal injury and acute respiratory distress syndrome Julie C. Fitzgerald a,⁎, Alexis A. Topjian a , Andrew D. McInnes a , Peter Mattei b , John J. McCloskey a , Stuart H. Friess a , Todd J. Kilbaugh a a
Department of Anesthesiology and Critical Care Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA Department of General, Thoracic, and Fetal Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
b
Received 29 June 2011; revised 6 September 2011; accepted 7 September 2011
Key words: Extracorporeal membrane oxygenation; High-frequency percussive ventilation; Acute respiratory distress syndrome; Postintubation tracheal injury; Mediastinal emphysema
Abstract Bi-caval dual lumen venovenous extracorporeal membrane oxygenation (VV-ECMO) as a nonoperative approach to postintubation tracheal injury has not been described. We report the case of a 7-year-old boy who sustained a postintubation tracheal injury, developed acute respiratory distress syndrome from aspiration and viral pneumonitis, and was supported on bi-caval dual lumen VV-ECMO for 16 days until the trachea healed without surgical repair. Before ECMO decannulation, highfrequency percussive ventilation using a volumetric diffusive respiration ventilator was used for lung recruitment and airway clearance without disruption of the healed trachea. The use of ECMO to allow for lower mean airway pressure during initial healing and high-frequency percussive ventilation for lung recruitment and secretion clearance is a promising strategy to allow nonoperative tracheal injury repair in critically ill patients with multiple comorbidities. © 2011 Elsevier Inc. All rights reserved.
Lung-protective strategies to treat acute respiratory distress syndrome (ARDS) such as high-frequency oscillatory ventilation (HFOV) and high-frequency percussive ventilation (HFPV) are often used to maintain lung recruitment while minimizing peak airway pressures and barotrauma [1] with use of venovenous extracorporeal membrane oxygenation (VV-ECMO) as a rescue strategy for refractory ARDS [2,3]. One type of HFPV,
⁎ Corresponding author. Tel.: +1 267 426 2344. E-mail address: [email protected] (J.C. Fitzgerald). 0022-3468/$ – see front matter © 2011 Elsevier Inc. All rights reserved. doi:10.1016/j.jpedsurg.2011.09.048
the Volumetric Diffusive Respiration (VDR) ventilator (Percussionaire Corp, Sandpoint, ID), an advanced mechanical ventilation strategy that allows for better oxygenation and ventilation at lower peak inspiratory pressures (PIP), is associated with less barotrauma than conventional ventilation [4-6] and may improve airway clearance [7]. We report a pediatric patient with a postintubation tracheal injury, severe air leak syndrome, and ARDS who was supported with bicaval dual-lumen VV-ECMO to allow tracheal healing by secondary intention and HFPV with the VDR ventilator for lung recruitment and airway clearance.
E12
1. Case report A 7-year-old, 51-kg boy with epilepsy and autism had several episodes of emesis followed by a generalized tonicclonic seizure at school. He was given 10 mg of rectal diazepam and was unresponsive when medics arrived. He was induced with etomidate without neuromuscular blockade and intubated by direct laryngoscopy with a styletted 6.0 cuffed endotracheal tube (ETT). During transport, he had a second episode of vomiting, and on arrival to the emergency department, he was gagging and had vomitus in his ETT. In the emergency department, his physical examination was pertinent for progressing crepitus over his neck and chest. Because of the patient vocalizing and the vomitus in the ETT, as described by the emergency physician, there was a concern for ETT dislodgement. The ETT was removed, and he was induced with etomidate and rocuronium and subsequently reintubated with a styletted 5.0 cuffed ETT. A chest radiograph obtained after reintubation confirmed appropriate ETT position, pneumomediastinum, and subcutaneous emphysema. He was transferred to the pediatric intensive care unit (PICU) for further management. On presentation to the PICU, a chest radiograph revealed extension of the pneumomediastinum and bilateral pulmonary infiltrates (Fig. 1A). He developed progressive air leak syndrome and ARDS with a minimum PaO2–to–fraction of inspired oxygen ratio of 79 and maximum oxygenation index of 22 in the first 12 hours after PICU admission. Respiratory viral testing was positive for metapneumovirus. The mean airway pressure was increased to improve oxygenation but resulted in worsening pneumomediastinum and subcutaneous emphysema. Bronchoscopy revealed a large defect of the posterior trachea just proximal to the carina (Fig. 1B). Chest computed tomography (CT) scan revealed a diverticular-like sac measuring 2.2 × 0.7 × 1 cm in the distal trachea with an area of discontinuity measuring 0.6 × 0.8 cm in the inferiorposterior portion of the diverticulum (Fig. 1C). The patient had significant worsening of oxygenation and hemodynamic status during the transport to CT. On return to the PICU, he
J.C. Fitzgerald et al. was briefly managed with HFOV without improvement in oxygenation. His oxygenation index had increased to 50, and he was subsequently cannulated for VV-ECMO. Possible therapies considered before ECMO cannulation included primary surgical repair supported by single lung ventilation, primary operative repair supported by ECMO, or bi-caval dual lumen VV-ECMO as a nonoperative approach. Because of rapidly progressive ARDS, neither placement of a double-lumen ETT nor single lung ventilation was implemented. Emergent thoracotomy for primary operative repair was considered high risk with his worsening oxygenation and hemodynamic status. Ultimately, the patient was taken to the operating room for placement of a 27F Avalon bi-caval dual lumen catheter (Avalon Laboratories, LLC, Rancho Dominguez, CA) through his right internal jugular vein under fluoroscopic guidance. He was maintained on VV-ECMO for 16 days. He was also treated with antibiotics for 10 days for mediastinitis prophylaxis. The patient was initially maintained on low conventional ventilator settings with a PIP of 10 cm H2O, positive endexpiratory pressure (PEEP) of 5 cm H2O, and intermittent mechanical ventilation rate of 10. The ECMO flow rate was maintained at 55 mL/kg/min, and PaO2 ranged from 45 to 60 mm Hg. Exhaled tidal volume was undetectable on the ventilator. Starting on day 6 of VV-ECMO, mean airway pressures were gradually increased over 5 days to a PIP of 20 and PEEP of 10 with no improvement on the chest radiograph and continued undetectable exhaled tidal volume. Bronchoscopy on day 11 of VV-ECMO revealed granulation tissue covering the tracheal injury (Fig. 2A) and thick secretions in the upper airway. Recruitment maneuvers, conversion to airway pressure release ventilation with a mean airway pressure of 22 cm H2O, and secretion clearance from this bronchoscopy did not improve lung recruitment. Repeat bronchoscopies were performed daily from days 14 through 16 of bi-caval dual lumen VV-ECMO to facilitate clearance of thick, copious secretions from the lower airways and aid lung recruitment. After bronchoscopy on day 14, the patient was converted to the VDR ventilator with a
Fig. 1 A, Chest radiograph after PICU admission shows pneumomediastinum and bilateral pulmonary infiltrates. B, Bronchoscopy image showing large posterior tracheal defect above carina. C, CT reconstruction of trachea. Arrow indicates tracheal defect.
Bi-caval dual lumen VV-ECMO and HFPV for tracheal injury
E13
Fig. 2 A, Bronchoscopy image of healing tracheal injury on ECMO day 11. B, Chest radiograph on ECMO day 15 after 24 hours of HFPV shows improved aeration of lungs. C, Bronchoscopy image on ECMO day 15 shows continued healing of tracheal injury.
convective PEEP of 10, convective PIP of 30, conventional rate of 20, inspiratory time of 1.5 seconds, percussive rate of 550, and mean airway pressure of 18 to 19 cm H2O. Chest radiograph after 1 hour of HFPV showed improved aeration of the right lung. Brisk secretion clearance from the ETT was noted within the first 12 hours on HFPV. Repeat bronchoscopy was performed after 24 hours of HFPV, and follow-up chest radiograph showed that both lungs were completely expanded (Fig. 2B). Continued healing of the tracheal injury was seen on bronchoscopy on bi-caval dual lumen VVECMO day 15 (Fig. 2C). There was no sign of air leak recurrence on radiograph or clinical examination. The patient was decannulated from ECMO on day 16 and maintained on HFPV for 4 more days at which point he was converted to conventional volume ventilation. He was successfully extubated 38 days after PICU admission and was transferred to the general inpatient ward breathing spontaneously on room air 45 days after PICU admission.
2. Discussion Postintubation tracheal injury is rare but carries a high mortality rate. A meta-analysis of case reports and case series in adults showed an overall mortality rate of 22% for postintubation tracheal injury with emergent intubation increasing the mortality risk 3-fold compared with elective intubation [8]. Nonoperative management of postintubation tracheobronchial injuries in adults is becoming widely accepted for selected patients. Patients who may benefit from a nonoperative approach include those spontaneously breathing and those on mechanical ventilation who do not have clinical progression of air leak and respiratory insufficiency [8-11]. Given the location of our patient's injury, his size, his progressive ARDS, and his hemodynamic instability, anesthetic management and primary surgical repair would have been challenging. Therefore, bi-caval dual lumen VV-ECMO cannulation in the operating room under fluoroscopic guidance was chosen as a strategy to decrease
mean airway pressure and to allow healing of the tracheal injury, to decrease severe air leak syndrome, and to allow the patient time to recover from ARDS (likely viral pneumonitis exacerbated by aspiration). Venovenous extracorporeal membrane oxygenation served as a bridge to maintain oxygenation and ventilation in our patient when conventional therapies and advanced modes of mechanical ventilation failed. Cannulation was performed in the operating room because of the need for radiographic guidance (echocardiographic or fluoroscopic) to ensure proper positioning because cannula position is important for proper blood flow and ejection across the tricuspid valve and to reduce the potential for vascular injury with placement via Seldinger technique. Once tracheal healing was confirmed by bronchoscopy in our patient, conventional recruitment methods, including increased mean airway pressure, were unable to recruit his lungs. The HFPV strategy, combined with frequent bronchoscopy to both confirm integrity of the airway and to aid in focused secretion clearance, was chosen because of the decreased risk of barotrauma and the possibility of improving both lung recruitment at lower mean airway pressure and secretion clearance with the VDR ventilator. This strategy successfully recruited the lungs without disrupting the healed injury in the distal trachea. This manifested as improvement in lung aeration evidenced by chest radiograph, physical examination findings, and increase in the patient's PaO2. Extracorporeal membrane oxygenation has been described in the perioperative management of tracheal and bronchial injuries [12-15]. One pediatric case report describes an attempt to use ECMO to allow healing of a tracheal injury by secondary intention; however, definitive surgical repair of the airway was ultimately necessary [12]. Notably, HFOV was used to aid lung recruitment after tracheal repair on ECMO in this case. To date, there is no published report of bi-caval dual lumen VV-ECMO combined with alternative methods of ventilation to facilitate tracheal healing, lung recruitment, and secretion clearance without primary surgical repair of postintubation tracheal
E14
Fig. 3 Pressure waveform of VDR ventilator. Oscillations occur during exhalation (E) at a lower pressure, the convective PEEP, and during inhalation (I) at a higher convective PIP. The convective I:E ratio is typically 1:1.
injury. In contrast to venoarterial ECMO, VV-ECMO does not require carotid artery access or ligation. Bi-caval dual lumen VV-ECMO uses a single venous site and a dual-lumen catheter that draws blood from the superior and inferior vena cava and ejects oxygenated blood across the tricuspid valve. The use of bi-caval dual lumen VV-ECMO support for respiratory failure is an emerging rescue strategy [3]. The proposed advantages over traditional VV-ECMO are reduced recirculation, decreased potential for catheter-site complications, and increased mobility. Despite these potential advantages, successful ECMO decannulation is still dependent on improvement in ARDS and lung recruitment, which may be aided by the addition of HFPV. The principle of HFPV is the use of small tidal volumes and rapid respiratory rates to promote gas exchange through longitudinal dispersion, pendelluft, bulk flow, and changes in the airflow dynamics in the airway [7]. The VDR ventilator is a flow-regulated, time-cycled, and pressurelimited pneumatic ventilator that combines the principles of conventional ventilation with superimposed high-frequency percussion (Fig. 3). The inspiration is composed of a stepwise series of small volumes at high frequency that stack to create the convective breath. The inspiratory and expiratory times are matched, and maximum PIP achieved during the oscillations during inspiration is set on the ventilator. Exhalation is passive to the PEEP set on the ventilator. High-frequency percussive ventilation is typically used as an advanced mode of mechanical ventilation for severe ARDS and for burn patients with inhalational injury who require aggressive airway clearance. It has been used to minimize barotrauma [6,16] and to improve airway secretion clearance to facilitate lung recruitment and improve compliance [7]. In small randomized trials in children and adults, HFPV has been shown to improve oxygenation and ventilation at lower mean airway pressures than conventional mechanical ventilation [4,17]; however, no random-
J.C. Fitzgerald et al. ized trial has shown a survival benefit. When compared with other high-frequency strategies used in patients with ARDS, HFPV maintains the benefits of other open lung strategies of ventilation that minimize ventilator-induced lung injury by reducing barotrauma from high peak inspiratory pressures and decreasing atelectotrauma while alleviating the need for neuromuscular blockade and improving secretion clearance [7]. Anecdotally, we have found that the presence of thick, inspisated secretions is a barrier to lung recruitment when preparing to separate from ECMO support in children with ARDS. Use of HFPV in this case improved secretion clearance and lung recruitment, facilitating decannulation. Prospective trials of different methods to optimize lung recruitment before ECMO decannulation may be informative, and HFPV may be an exciting form of ventilation to promote low mean airway pressure, secretion clearance, and lung recruitment to expedite EMCO decannulation.
References [1] Esan A, Hess DR, Raoof S, et al. Severe hypoxemic respiratory failure part 1—ventilatory strategies. Chest 2010;137:1203-16. [2] Raoof S, Goulet K, Esan A, et al. Severe hypoxemic respiratory failure part 2—nonventilatory strategies. Chest 2010;137:1437-48. [3] Javidfar J, Brodie D, Wang D, et al. Use of bicaval dual-lumen catheter for adult venovenous extracorporeal membrane oxygenation. Ann Thorac Surg 2011;91:1763-9. [4] Carman B, Cahill T, Warden G, et al. A prospective, randomized comparison of the volume diffusive respirator vs conventional ventilation for ventilation of burned children. 2001 ABA paper. J Burn Care Rehabil 2002;23:444-8. [5] Rodeberg DA, Housinger TA, Greenhalgh DG, et al. Improved ventilatory function in burn patients using volumetric diffusive respiration. J Am Coll Surg 1994;179:518-22. [6] Rodeberg DA, Maschinot NE, Housinger TA, et al. Decreased pulmonary barotrauma with the use of volumetric diffusive respiration in pediatric patients with burns: the 1992 Moyer Award. J Burn Care Rehabil 1992;13:506-11. [7] Salim A, Martin M. High-frequency percussive ventilation. Crit Care Med 2005;33(Suppl.):S241-5. [8] Minambres E, Buron J, Ballesteros MA, et al. Tracheal rupture after endotracheal intubation: a literature systematic review. Eur J Cardiothorac Surg 2009;35:1056-62. [9] Conti M, Pougeoise M, Wurtz A, et al. Management of postintubation tracheobronchial ruptures. Chest 2006;130:412-8. [10] Fong PA, Seder CW, Chmielewski GW, et al. Nonoperative managment of postintubation tracheal injuries. Ann Thorac Surg 2010;89:1265-6. [11] Gomez-Caro A, Ausin P, Moradiellos FJ, et al. Role of conservative medical management of tracheobronchial injuries. J Trauma 2006;61: 1426-35. [12] Goldman AP, Macrae DJ, Tasker RC, et al. Extracorporeal membrane oxygenation as a bridge to definitive tracheal surgery in children. J Pediatr 1996;128:386-8. [13] Voelckel W, Wenzel V, Rieger M, et al. Temporary extracorporeal membrane oxygenation in the treatment of acute traumatic lung injury. Can J Anaesth 1998;45:1097-102. [14] Korvenoja P, Pitkanen O, Berg E, et al. Veno-venous extracorporeal membrane oxygenation in surgery for bronchial repair. Ann Thorac Surg 2008;86:1348-9.
Bi-caval dual lumen VV-ECMO and HFPV for tracheal injury [15] Campione A, Agostini M, Portolan M, et al. Extracorporeal membrane oxygenation in respiratory failure for pulmonary contusion and bronchial disruption after trauma. J Thorac Cardiovasc Surg 2007;133:1673-4. [16] Smith DW, Frankel LR, Derish MT, et al. High-frequency jet ventilation in children with the adult respiratory distress syndrome
E15 complicated by pulmonary barotrauma. Pediatr Pulmonol 1993;15: 279-86. [17] Hurst JM, Branson RD, Davis K, et al. Comparison of conventional mechanical ventilation and high-frequency ventilation. A prospective, randomized trial in patients with respiratory failure. Ann Surg 1990;211:486-91.
www.elsevier.com/locate/jpedsurg
Bi-caval dual lumen venovenous extracorporeal membrane oxygenation and high-frequency percussive ventilatory support for postintubation tracheal injury and acute respiratory distress syndrome Julie C. Fitzgerald a,⁎, Alexis A. Topjian a , Andrew D. McInnes a , Peter Mattei b , John J. McCloskey a , Stuart H. Friess a , Todd J. Kilbaugh a a
Department of Anesthesiology and Critical Care Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA Department of General, Thoracic, and Fetal Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
b
Received 29 June 2011; revised 6 September 2011; accepted 7 September 2011
Key words: Extracorporeal membrane oxygenation; High-frequency percussive ventilation; Acute respiratory distress syndrome; Postintubation tracheal injury; Mediastinal emphysema
Abstract Bi-caval dual lumen venovenous extracorporeal membrane oxygenation (VV-ECMO) as a nonoperative approach to postintubation tracheal injury has not been described. We report the case of a 7-year-old boy who sustained a postintubation tracheal injury, developed acute respiratory distress syndrome from aspiration and viral pneumonitis, and was supported on bi-caval dual lumen VV-ECMO for 16 days until the trachea healed without surgical repair. Before ECMO decannulation, highfrequency percussive ventilation using a volumetric diffusive respiration ventilator was used for lung recruitment and airway clearance without disruption of the healed trachea. The use of ECMO to allow for lower mean airway pressure during initial healing and high-frequency percussive ventilation for lung recruitment and secretion clearance is a promising strategy to allow nonoperative tracheal injury repair in critically ill patients with multiple comorbidities. © 2011 Elsevier Inc. All rights reserved.
Lung-protective strategies to treat acute respiratory distress syndrome (ARDS) such as high-frequency oscillatory ventilation (HFOV) and high-frequency percussive ventilation (HFPV) are often used to maintain lung recruitment while minimizing peak airway pressures and barotrauma [1] with use of venovenous extracorporeal membrane oxygenation (VV-ECMO) as a rescue strategy for refractory ARDS [2,3]. One type of HFPV,
⁎ Corresponding author. Tel.: +1 267 426 2344. E-mail address: [email protected] (J.C. Fitzgerald). 0022-3468/$ – see front matter © 2011 Elsevier Inc. All rights reserved. doi:10.1016/j.jpedsurg.2011.09.048
the Volumetric Diffusive Respiration (VDR) ventilator (Percussionaire Corp, Sandpoint, ID), an advanced mechanical ventilation strategy that allows for better oxygenation and ventilation at lower peak inspiratory pressures (PIP), is associated with less barotrauma than conventional ventilation [4-6] and may improve airway clearance [7]. We report a pediatric patient with a postintubation tracheal injury, severe air leak syndrome, and ARDS who was supported with bicaval dual-lumen VV-ECMO to allow tracheal healing by secondary intention and HFPV with the VDR ventilator for lung recruitment and airway clearance.
E12
1. Case report A 7-year-old, 51-kg boy with epilepsy and autism had several episodes of emesis followed by a generalized tonicclonic seizure at school. He was given 10 mg of rectal diazepam and was unresponsive when medics arrived. He was induced with etomidate without neuromuscular blockade and intubated by direct laryngoscopy with a styletted 6.0 cuffed endotracheal tube (ETT). During transport, he had a second episode of vomiting, and on arrival to the emergency department, he was gagging and had vomitus in his ETT. In the emergency department, his physical examination was pertinent for progressing crepitus over his neck and chest. Because of the patient vocalizing and the vomitus in the ETT, as described by the emergency physician, there was a concern for ETT dislodgement. The ETT was removed, and he was induced with etomidate and rocuronium and subsequently reintubated with a styletted 5.0 cuffed ETT. A chest radiograph obtained after reintubation confirmed appropriate ETT position, pneumomediastinum, and subcutaneous emphysema. He was transferred to the pediatric intensive care unit (PICU) for further management. On presentation to the PICU, a chest radiograph revealed extension of the pneumomediastinum and bilateral pulmonary infiltrates (Fig. 1A). He developed progressive air leak syndrome and ARDS with a minimum PaO2–to–fraction of inspired oxygen ratio of 79 and maximum oxygenation index of 22 in the first 12 hours after PICU admission. Respiratory viral testing was positive for metapneumovirus. The mean airway pressure was increased to improve oxygenation but resulted in worsening pneumomediastinum and subcutaneous emphysema. Bronchoscopy revealed a large defect of the posterior trachea just proximal to the carina (Fig. 1B). Chest computed tomography (CT) scan revealed a diverticular-like sac measuring 2.2 × 0.7 × 1 cm in the distal trachea with an area of discontinuity measuring 0.6 × 0.8 cm in the inferiorposterior portion of the diverticulum (Fig. 1C). The patient had significant worsening of oxygenation and hemodynamic status during the transport to CT. On return to the PICU, he
J.C. Fitzgerald et al. was briefly managed with HFOV without improvement in oxygenation. His oxygenation index had increased to 50, and he was subsequently cannulated for VV-ECMO. Possible therapies considered before ECMO cannulation included primary surgical repair supported by single lung ventilation, primary operative repair supported by ECMO, or bi-caval dual lumen VV-ECMO as a nonoperative approach. Because of rapidly progressive ARDS, neither placement of a double-lumen ETT nor single lung ventilation was implemented. Emergent thoracotomy for primary operative repair was considered high risk with his worsening oxygenation and hemodynamic status. Ultimately, the patient was taken to the operating room for placement of a 27F Avalon bi-caval dual lumen catheter (Avalon Laboratories, LLC, Rancho Dominguez, CA) through his right internal jugular vein under fluoroscopic guidance. He was maintained on VV-ECMO for 16 days. He was also treated with antibiotics for 10 days for mediastinitis prophylaxis. The patient was initially maintained on low conventional ventilator settings with a PIP of 10 cm H2O, positive endexpiratory pressure (PEEP) of 5 cm H2O, and intermittent mechanical ventilation rate of 10. The ECMO flow rate was maintained at 55 mL/kg/min, and PaO2 ranged from 45 to 60 mm Hg. Exhaled tidal volume was undetectable on the ventilator. Starting on day 6 of VV-ECMO, mean airway pressures were gradually increased over 5 days to a PIP of 20 and PEEP of 10 with no improvement on the chest radiograph and continued undetectable exhaled tidal volume. Bronchoscopy on day 11 of VV-ECMO revealed granulation tissue covering the tracheal injury (Fig. 2A) and thick secretions in the upper airway. Recruitment maneuvers, conversion to airway pressure release ventilation with a mean airway pressure of 22 cm H2O, and secretion clearance from this bronchoscopy did not improve lung recruitment. Repeat bronchoscopies were performed daily from days 14 through 16 of bi-caval dual lumen VV-ECMO to facilitate clearance of thick, copious secretions from the lower airways and aid lung recruitment. After bronchoscopy on day 14, the patient was converted to the VDR ventilator with a
Fig. 1 A, Chest radiograph after PICU admission shows pneumomediastinum and bilateral pulmonary infiltrates. B, Bronchoscopy image showing large posterior tracheal defect above carina. C, CT reconstruction of trachea. Arrow indicates tracheal defect.
Bi-caval dual lumen VV-ECMO and HFPV for tracheal injury
E13
Fig. 2 A, Bronchoscopy image of healing tracheal injury on ECMO day 11. B, Chest radiograph on ECMO day 15 after 24 hours of HFPV shows improved aeration of lungs. C, Bronchoscopy image on ECMO day 15 shows continued healing of tracheal injury.
convective PEEP of 10, convective PIP of 30, conventional rate of 20, inspiratory time of 1.5 seconds, percussive rate of 550, and mean airway pressure of 18 to 19 cm H2O. Chest radiograph after 1 hour of HFPV showed improved aeration of the right lung. Brisk secretion clearance from the ETT was noted within the first 12 hours on HFPV. Repeat bronchoscopy was performed after 24 hours of HFPV, and follow-up chest radiograph showed that both lungs were completely expanded (Fig. 2B). Continued healing of the tracheal injury was seen on bronchoscopy on bi-caval dual lumen VVECMO day 15 (Fig. 2C). There was no sign of air leak recurrence on radiograph or clinical examination. The patient was decannulated from ECMO on day 16 and maintained on HFPV for 4 more days at which point he was converted to conventional volume ventilation. He was successfully extubated 38 days after PICU admission and was transferred to the general inpatient ward breathing spontaneously on room air 45 days after PICU admission.
2. Discussion Postintubation tracheal injury is rare but carries a high mortality rate. A meta-analysis of case reports and case series in adults showed an overall mortality rate of 22% for postintubation tracheal injury with emergent intubation increasing the mortality risk 3-fold compared with elective intubation [8]. Nonoperative management of postintubation tracheobronchial injuries in adults is becoming widely accepted for selected patients. Patients who may benefit from a nonoperative approach include those spontaneously breathing and those on mechanical ventilation who do not have clinical progression of air leak and respiratory insufficiency [8-11]. Given the location of our patient's injury, his size, his progressive ARDS, and his hemodynamic instability, anesthetic management and primary surgical repair would have been challenging. Therefore, bi-caval dual lumen VV-ECMO cannulation in the operating room under fluoroscopic guidance was chosen as a strategy to decrease
mean airway pressure and to allow healing of the tracheal injury, to decrease severe air leak syndrome, and to allow the patient time to recover from ARDS (likely viral pneumonitis exacerbated by aspiration). Venovenous extracorporeal membrane oxygenation served as a bridge to maintain oxygenation and ventilation in our patient when conventional therapies and advanced modes of mechanical ventilation failed. Cannulation was performed in the operating room because of the need for radiographic guidance (echocardiographic or fluoroscopic) to ensure proper positioning because cannula position is important for proper blood flow and ejection across the tricuspid valve and to reduce the potential for vascular injury with placement via Seldinger technique. Once tracheal healing was confirmed by bronchoscopy in our patient, conventional recruitment methods, including increased mean airway pressure, were unable to recruit his lungs. The HFPV strategy, combined with frequent bronchoscopy to both confirm integrity of the airway and to aid in focused secretion clearance, was chosen because of the decreased risk of barotrauma and the possibility of improving both lung recruitment at lower mean airway pressure and secretion clearance with the VDR ventilator. This strategy successfully recruited the lungs without disrupting the healed injury in the distal trachea. This manifested as improvement in lung aeration evidenced by chest radiograph, physical examination findings, and increase in the patient's PaO2. Extracorporeal membrane oxygenation has been described in the perioperative management of tracheal and bronchial injuries [12-15]. One pediatric case report describes an attempt to use ECMO to allow healing of a tracheal injury by secondary intention; however, definitive surgical repair of the airway was ultimately necessary [12]. Notably, HFOV was used to aid lung recruitment after tracheal repair on ECMO in this case. To date, there is no published report of bi-caval dual lumen VV-ECMO combined with alternative methods of ventilation to facilitate tracheal healing, lung recruitment, and secretion clearance without primary surgical repair of postintubation tracheal
E14
Fig. 3 Pressure waveform of VDR ventilator. Oscillations occur during exhalation (E) at a lower pressure, the convective PEEP, and during inhalation (I) at a higher convective PIP. The convective I:E ratio is typically 1:1.
injury. In contrast to venoarterial ECMO, VV-ECMO does not require carotid artery access or ligation. Bi-caval dual lumen VV-ECMO uses a single venous site and a dual-lumen catheter that draws blood from the superior and inferior vena cava and ejects oxygenated blood across the tricuspid valve. The use of bi-caval dual lumen VV-ECMO support for respiratory failure is an emerging rescue strategy [3]. The proposed advantages over traditional VV-ECMO are reduced recirculation, decreased potential for catheter-site complications, and increased mobility. Despite these potential advantages, successful ECMO decannulation is still dependent on improvement in ARDS and lung recruitment, which may be aided by the addition of HFPV. The principle of HFPV is the use of small tidal volumes and rapid respiratory rates to promote gas exchange through longitudinal dispersion, pendelluft, bulk flow, and changes in the airflow dynamics in the airway [7]. The VDR ventilator is a flow-regulated, time-cycled, and pressurelimited pneumatic ventilator that combines the principles of conventional ventilation with superimposed high-frequency percussion (Fig. 3). The inspiration is composed of a stepwise series of small volumes at high frequency that stack to create the convective breath. The inspiratory and expiratory times are matched, and maximum PIP achieved during the oscillations during inspiration is set on the ventilator. Exhalation is passive to the PEEP set on the ventilator. High-frequency percussive ventilation is typically used as an advanced mode of mechanical ventilation for severe ARDS and for burn patients with inhalational injury who require aggressive airway clearance. It has been used to minimize barotrauma [6,16] and to improve airway secretion clearance to facilitate lung recruitment and improve compliance [7]. In small randomized trials in children and adults, HFPV has been shown to improve oxygenation and ventilation at lower mean airway pressures than conventional mechanical ventilation [4,17]; however, no random-
J.C. Fitzgerald et al. ized trial has shown a survival benefit. When compared with other high-frequency strategies used in patients with ARDS, HFPV maintains the benefits of other open lung strategies of ventilation that minimize ventilator-induced lung injury by reducing barotrauma from high peak inspiratory pressures and decreasing atelectotrauma while alleviating the need for neuromuscular blockade and improving secretion clearance [7]. Anecdotally, we have found that the presence of thick, inspisated secretions is a barrier to lung recruitment when preparing to separate from ECMO support in children with ARDS. Use of HFPV in this case improved secretion clearance and lung recruitment, facilitating decannulation. Prospective trials of different methods to optimize lung recruitment before ECMO decannulation may be informative, and HFPV may be an exciting form of ventilation to promote low mean airway pressure, secretion clearance, and lung recruitment to expedite EMCO decannulation.
References [1] Esan A, Hess DR, Raoof S, et al. Severe hypoxemic respiratory failure part 1—ventilatory strategies. Chest 2010;137:1203-16. [2] Raoof S, Goulet K, Esan A, et al. Severe hypoxemic respiratory failure part 2—nonventilatory strategies. Chest 2010;137:1437-48. [3] Javidfar J, Brodie D, Wang D, et al. Use of bicaval dual-lumen catheter for adult venovenous extracorporeal membrane oxygenation. Ann Thorac Surg 2011;91:1763-9. [4] Carman B, Cahill T, Warden G, et al. A prospective, randomized comparison of the volume diffusive respirator vs conventional ventilation for ventilation of burned children. 2001 ABA paper. J Burn Care Rehabil 2002;23:444-8. [5] Rodeberg DA, Housinger TA, Greenhalgh DG, et al. Improved ventilatory function in burn patients using volumetric diffusive respiration. J Am Coll Surg 1994;179:518-22. [6] Rodeberg DA, Maschinot NE, Housinger TA, et al. Decreased pulmonary barotrauma with the use of volumetric diffusive respiration in pediatric patients with burns: the 1992 Moyer Award. J Burn Care Rehabil 1992;13:506-11. [7] Salim A, Martin M. High-frequency percussive ventilation. Crit Care Med 2005;33(Suppl.):S241-5. [8] Minambres E, Buron J, Ballesteros MA, et al. Tracheal rupture after endotracheal intubation: a literature systematic review. Eur J Cardiothorac Surg 2009;35:1056-62. [9] Conti M, Pougeoise M, Wurtz A, et al. Management of postintubation tracheobronchial ruptures. Chest 2006;130:412-8. [10] Fong PA, Seder CW, Chmielewski GW, et al. Nonoperative managment of postintubation tracheal injuries. Ann Thorac Surg 2010;89:1265-6. [11] Gomez-Caro A, Ausin P, Moradiellos FJ, et al. Role of conservative medical management of tracheobronchial injuries. J Trauma 2006;61: 1426-35. [12] Goldman AP, Macrae DJ, Tasker RC, et al. Extracorporeal membrane oxygenation as a bridge to definitive tracheal surgery in children. J Pediatr 1996;128:386-8. [13] Voelckel W, Wenzel V, Rieger M, et al. Temporary extracorporeal membrane oxygenation in the treatment of acute traumatic lung injury. Can J Anaesth 1998;45:1097-102. [14] Korvenoja P, Pitkanen O, Berg E, et al. Veno-venous extracorporeal membrane oxygenation in surgery for bronchial repair. Ann Thorac Surg 2008;86:1348-9.
Bi-caval dual lumen VV-ECMO and HFPV for tracheal injury [15] Campione A, Agostini M, Portolan M, et al. Extracorporeal membrane oxygenation in respiratory failure for pulmonary contusion and bronchial disruption after trauma. J Thorac Cardiovasc Surg 2007;133:1673-4. [16] Smith DW, Frankel LR, Derish MT, et al. High-frequency jet ventilation in children with the adult respiratory distress syndrome
E15 complicated by pulmonary barotrauma. Pediatr Pulmonol 1993;15: 279-86. [17] Hurst JM, Branson RD, Davis K, et al. Comparison of conventional mechanical ventilation and high-frequency ventilation. A prospective, randomized trial in patients with respiratory failure. Ann Surg 1990;211:486-91.