Editorials
Extubation and Extracorporeal Membrane Oxygenation: What a Difference a Decade Makes!!* Heidi J. Dalton, MD Critical Care Medicine Phoenix Children’s Hospital Phoenix, AZ; and Child Health University of Arizona College of Medicine-Phoenix Phoenix, AZ
A
long with the rise of smartphones, apps for everything, social media, electric cars and miniaturization of items from computers to televisions, changes in the medical environment include the rise in the use of extracorporeal membrane oxygenation (ECMO) and changes in patient management associated with it. Much of the current shift in the acceptance of ECMO as a viable technique in patients with severe cardiac or respiratory failure, cardiac arrest or as a bridge to transplant has come with the changes in technology that have occurred over the past few years. Smaller and more efficient pumps, oxygenators and tubing configurations now allow ECMO to be set up, primed and ready for use almost instantaneously (1, 2). Cannulas with improved flow dynamics that can support infants through adults are available and experience gained is resulting in improved cannulation techniques and potentially safer routes for access. Along with technology, research in critical care has shown us that many “traditional” approaches to patient care may actually be harmful—from mechanical ventilation, immobility and the overuse of sedative agents designed to keep patients “comfortable” during their intensive care stay (3, 4). Maintaining sedation to the point of coma was for many years a hallmark in critically ill patients such as those receiving ECMO. Limiting metabolic demands in these critically ill patients coupled with concern over the potential adverse effects on pump flow or cannula position that would impair function of the extracorporeal support system kept many patient sedated and receiving neuromuscular blockade for days or weeks on end (5). Indeed, for patients requiring prolonged ECMO, withdrawal from narcotic medications received during ECMO kept many in the hospital long after their critical illness was resolved. As we are learning to limit such medications
*See also p. 861. Key Words: acute respiratory distress syndrome; extracorporeal membrane oxygenation; extracorporeal life support; extubation; respiratory failure Dr. Dalton lectured for rEVO Biologics and ThermoFisher and received support for the development of educational presentations from the Society of Critical Care Medicine (Pediatric Critical Care Medicine Board Review Course). Her institution received grant support from the National Institutes of Health. Copyright © 2014 by the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies DOI: 10.1097/PCC.0000000000000265
Pediatric Critical Care Medicine
in other critically ill patients, so too has ECMO seen a paradigm shift in this area. The current trend to maintain ECMO patients in as “awake” state as possible is a dramatic example of how medicine is changing. Now, the concern is not so much as how MUCH a patient is allowed to move, but whether we are letting them move ENOUGH. Just as research has shown that patients with acute respiratory distress syndrome (ARDS) have prolonged muscle weakness and disability from their ICU illness, such has been noted in ECMO patients as well (6–8). The push to enteral nutrition and away from parenteral support also is improved by limiting narcotics and allowing more normal mobility. The current emphasis on eliminating pressure ulcers in hospitalized patients is equally or more important in ECMO patients, as wounds can increase the rate of infection or bleeding in patients who are already at high risk for these events (9, 10). Clinicians have also gained knowledge, from how best to operate on ECMO despite heparinization, how to limit SOME bleeding and thrombotic complications (although this remains the most frustrating problem in extracorporeal support) and that patients CAN be moved without adverse events (11, 12). Two other important factors have also appeared: first, that patients can be maintained on ECMO for weeks to months as a bridge to transplant or recovery (13, 14); second, in patients with severely diseased lungs on adequate ECMO support, use of mechanical ventilation is not needed nor may it be useful (15). Many reports of persistent subphysiologic tidal volumes despite high inflating pressures used during ECMO have shown us how futile trying to expand non-compliant lungs is—and reports from Sweden and other sites have for years advocated that the known course of ARDS takes WEEKS to recovery and that patience is more important than attempting to maintain tidal volume during ECMO with mechanical ventilation. New reports of patients who have been bridged to lung transplant have noted that recipients who are kept awake and are able to participate in physical therapy to maintain muscle strength tend to do better than those who aren’t (16). In this issue of Pediatric Critical Care Medicine, the current report by Antón-Martín et al (17) on the success of extubation during ECMO is another ripple in the shift that is occurring with ECMO. The advantages seem obvious: the ability for a patient to spontaneously breath, provide their own pulmonary toilet, eat orally, interact with family and caregivers and participate in exercise, schoolwork and activities of daily living which may all play a part in successful recovery. While some fear that losing whatever lung expansion is being maintained with mechanical ventilator support may retard healing, provide a breeding ground for infection and reduce the ability for mechanical means of removing secretions from the airways, there is little data that this is true. Research is also finding that maintaining stretch of damaged alveoli may www.pccmjournal.org
907
Editorials
induce cytokines that result in multiple organ failure or limit recovery (18–22). The current report is an excellent demonstration of how much ECMO care has evolved over the past few years (17). It also demonstrates how much ECMO remains a “team sport” (23). One good example of this is the focused ECMO physician team who provide consultative support to the primary service team. Given the long ECMO duration and complexities of patients supported, having such a focus team can help provide continuity and offer consultation to the primary service team on issues such as timing and advisability of extubation. Involving families, nursing, respiratory and support staff in these decisions is also important to promote success. The issues raised regarding the dyspnea noted in some patients, despite seemingly adequate oxygenation and ventilation via the ECMO circuit, have been noted by others and remain mysterious and often distressing (24). Whether this is related to intrinsic stretch receptor signals coming from consolidated lungs to initiate respiratory effort and try to improve tidal volume or other factors has yet to be elucidated. In some patients, the dyspnea can be reduced by driving down the carbon dioxide level in the blood returning to the brain via the ECMO circuit and eliminating the hypercarbic drive to breathe (25). In other patients, especially small infants, the ECMO circuit is so efficient at removing carbon dioxide that the patient has NO hypercarbic drive to breathe and may appear apneic. For some patients, however, it seems as if no adjustment in the ECMO circuit can lessen the patient’s spontaneous efforts. One caveat in this circumstance is that unless the patient’s respiratory effort compromises extracorporeal pump flow, it is often more distressing to the caregivers than it is to the patient. Patient’s may report feeling “fine” even with nasal flaring and visual signs of respiratory distress. Learning to adjust to these aspects of care in an extubated ECMO patient requires buy-in from all team members, including the family. While the benefits of extubation in terms of decreased sedation, increased mobility and interaction with the environment are notable, adoption of this practice requires careful planning. As noted in the Anton-Martin report, emergent reintubation for assistance with resuscitation was required in 1 patient. Several other patients were reintubated for “recruitment”—it would be interesting to know exactly “why” these decisions were made and how long after reintubation the survivors were weaned from ECMO. Clearly, the loudest argument AGAINST extubation during ECMO comes from camps who believe that maintaining positive pressure is required to prevent complete atelectasis during ECMO and that measures to improve tidal volume, whether with airway pressure or clearance procedures are a vital part of patient care (26). Arguing against this is the lack of expansion obtained, even with high levels of ventilator support, that has been noted in patients with severe ARDS and the rationale that exposing the patient to high levels of positive pressure or repeated therapies such as bronchoscopy (unless removing mucous plugs or obstructions) or other intermittent airway clearance modalities merely encourages more cytokine formation and may place the patient at higher risk of airleak or bleeding (27). Spontaneous breathing efforts, even in 908
www.pccmjournal.org
consolidated lungs, may promote lymphatic drainage from the pulmonary bed which may be beneficial (15, 28, 29). It is evident that further research in the area of how best to “treat” the lung during ECMO for respiratory and cardiac support is needed (30). The current trend towards extubation in many centers highlights the need for a team effort with procedures and practices in place both to implement extubation safely, have readily available algorithms and equipment if reintubation is required and agreement among members that this is a goal for the patient (31, 32). As has been noted in several recent publications, titles such as “We don’t need mechanical ventilation anymore” (15), or “Extracorporeal gas exchange and spontaneous breathing as a treatment for acute respiratory distress syndrome: an alternative to mechanical ventilation?” (32), this novel approach to patient care during ECMO outlined in the current report is becoming more commonplace. Further investigation is needed to refine patient populations and management to improve outcomes. Investigation into the issues in dyspnea, which can result in interruption of pump flow from respiratory effort, are also required to allow successful use of extubation during the ECMO course.
REFERENES
1. Chai PJ, Jacobs JP, Dalton HJ, et al: Extracorporeal cardiopulmonary resuscitation for post-operative cardiac arrest: indications, techniques, controversies, and early results–what is known (and unknown). Cardiol Young 2011; 21 Suppl 2:109–117 2. Dalton HJ: Extracorporeal membrane oxygenation in the 21st century: a decade of change. Pediatr Crit Care Med 2011; 12:692–693 3. Azoulay E, Citerio G, Bakker J, et al: Year in review in Intensive Care Medicine 2013: II. Sedation, invasive and noninvasive ventilation, airways, ARDS, ECMO, family satisfaction, end-of-life care, organ donation, informed consent, safety, hematological issues in critically ill patients. Intensive Care Med 2014; 40:305–319 4. Adhikari NK, Tansey CM, McAndrews MP, et al: Self-reported depressive symptoms and memory complaints in survivors five years after ARDS. Chest 2011; 140:1484–1493 5. Andrews AF, Roloff DW, Bartlett RH: Use of extracorporeal membrane oxygenators in persistent pulmonary hypertension of the newborn. Clin Perinatol 1984; 11:729–735 6. Bartlett RH, Andrews AF, Toomasian JM, et al: Extracorporeal membrane oxygenation for newborn respiratory failure: forty-five cases. Surgery 1982; 92:425–433 7. Boykin AR, Quivers ES, Wagenhoffer KL, et al: Cardiopulmonary outcome of neonatal extracorporeal membrane oxygenation at ages 10-15 years. Crit Care Med 2003; 31:2380–2384 8. Andrews AF, Nixon CA, Cilley RE, et al: One- to three-year outcome for 14 neonatal survivors of extracorporeal membrane oxygenation. Pediatrics 1986; 78:692–698 9. Frenckner B, Ehrén H, Palmér K: Patient complications during extracorporeal membrane oxygenation (ECMO). Eur J Pediatr Surg 1991; 1:339–342 10. Bilen O, Loftis L, Teruya J: Severe thrombotic and bleeding complications in a baby with heterozygous factor V Leiden and acquired von Willebrand disease on ECMO. J Extra Corpor Technol 2011; 43:64–69 11. Haefner SM, Bratton SL, Annich GM, et al: Complications of intermittent prone positioning in pediatric patients receiving extracorporeal membrane oxygenation for respiratory failure. Chest 2003; 123:1589–1594 12. Munshi L, Fan E, Del Sorbo L: Prone position during ECMO: a turn of events? Minerva Anestesiol 2014; 80:281–283 13. Almond CS, Singh TP, Gauvreau K, et al: Extracorporeal membrane oxygenation for bridge to heart transplantation among children in the United States: analysis of data from the Organ Procurement and November 2014 • Volume 15 • Number 9
Editorials Transplant Network and Extracorporeal Life Support Organization Registry. Circulation 2011; 123:2975–2984 14. Haneya A, Philipp A, Mueller T, et al: Extracorporeal circulatory systems as a bridge to lung transplantation at remote transplant centers. Ann Thorac Surg 2011; 91:250–255 15. Del Sorbo L, Ranieri VM: We do not need mechanical ventilation any more. Crit Care Med 2010; 38:S555–S558 16. Turner DA, Cheifetz IM, Rehder KJ, et al: Active rehabilitation and physical therapy during extracorporeal membrane oxygenation while awaiting lung transplantation: a practical approach. Crit Care Med 2011; 39:2593–2598 17. Anton-Martin P, Thompson MT, Sheeran PD, et al: Extubation During Pediatric Extracorporeal Membrane Oxygenation: A Single-Center Experience. Pediatr Crit Care Med 2014; 15:861–869 18. Dixon DL, Barr HA, Bersten AD, et al: Intracellular storage of surfactant and proinflammatory cytokines in co-cultured alveolar epithelium and macrophages in response to increasing CO2 and cyclic cell stretch. Exp Lung Res 2008; 34:37–47 19. Bohrer B, Silveira RC, Neto EC, et al: Mechanical ventilation of newborns infant changes in plasma pro- and anti-inflammatory cytokines. J Pediatr 2010; 156:16–19 20. Vobruba V, Klimenko OV, Kobr J, et al: Effects of high tidal volume mechanical ventilation on production of cytokines, iNOS, and MIP-1β proteins in pigs. Exp Lung Res 2013; 39:1–8 21. Terragni PP, Del Sorbo L, Mascia L, et al: Tidal volume lower than 6 ml/kg enhances lung protection: role of extracorporeal carbon dioxide removal. Anesthesiology 2009; 111:826–835 22. Del Sorbo L, Goffi A, Ranieri VM: Mechanical ventilation during acute lung injury: current recommendations and new concepts. Presse Med 2011; 40:e569–e583 23. Turner DA, Williford WL, Peters MA, et al: Development of a collaborative program to provide extracorporeal membrane oxygenation for
adults with refractory hypoxemia within the framework of a pandemic. Pediatr Crit Care Med 2011; 12:426–430 24. Raake J, Johnson B, Seger B, et al: Extracorporeal membrane oxygenation, extubation, and lung-recruitment maneuvers as rescue therapy in a patient with tracheal dehiscence following slide tracheoplasty. Respir Care 2011; 56:1198–1202 25. Abrams DC, Brenner K, Burkart KM, et al: Pilot study of extracorporeal carbon dioxide removal to facilitate extubation and ambulation in exacerbations of chronic obstructive pulmonary disease. Ann Am Thorac Soc 2013; 10:307–314 26. Kamat PP, Popler J, Davis J, et al: Use of flexible bronchoscopy in pediatric patients receiving extracorporeal membrane oxygenation (ECMO) support. Pediatr Pulmonol 2011; 46:1108–1113 27. Bartsch H, Kössel H, Brummer G, et al: The influence of lung injury due to mechanical ventilation on the initiation of ECMO. Int J Artif Organs 1995; 18:565–568 28. Riquet M, Hidden G, Debesse B: Direct lymphatic drainage of lung segments to the mediastinal nodes. An anatomic study on 260 adults. J Thorac Cardiovasc Surg 1989; 97:623–632 29. Bobrrikov AV, Beliakov NA, Serikov VB: [Lymph flow and the vascular permeability of the lungs during spontaneous respiration and artificial pulmonary ventilation]. Anesteziol Reanimatol 1981; 3:28–32 30. Marhong JD, Telesnicki T, Munshi L, et al: Mechanical ventilation during extracorporeal membrane oxygenation. An international survey. Ann Am Thorac Soc 2014; 11:956–961 31. Duru JA, Menges T, Bodner J, et al: [Awake ECMO therapy in airway stenosis. Bronchoscopic treatment using laser resection]. Anaesthesist 2014; 63:401–405 32. Langer T, Vecchi V, Belenkiy SM, et al: Extracorporeal gas exchange and spontaneous breathing for the treatment of acute respiratory distress syndrome: an alternative to mechanical ventilation?*. Crit Care Med 2014; 42:e211–e220
Is This Heart Going to Work?* Steven Schwartz, MD Alejandro A. Floh, MD Department of Critical Care Medicine The Hospital for Sick Children Toronto, Ontario, Canada
E
xtracorporeal membrane oxygenation (ECMO) is commonly used as a short-term rescue for critically ill patients with cardiac and cardiac failure who are unable
*See also p. 870. Key Words: congenital heart disease; extracorporeal membrane oxygenation; heart failure; ventricular function Dr. Schwartz consulted for Novartis and provided expert testimony for Summers and Schwartz. His institution received grant support from the National Institutes of Health (NIH/National Heart, Lung and Blood Institutes) and the Heart and Stroke Foundation of Canada. Dr. Floh is employed by the Office of the Chief Coroner (Member of the provincial Pediatric Death Review Committee). His institution received grant support from the Pediatric Heart Network and the NIH (1-year funding for randomized study). Copyright © 2014 by the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies DOI: 10.1097/PCC.0000000000000266
Pediatric Critical Care Medicine
to meet their systemic output demands. Following initiation, patients are supported until the myocardium recovers sufficiently to allow for separation from circulatory support or they are transitioned to longer term devices while awaiting transplantation. Overall ECMO survival ranges from 35% to 60% but varies based on the indication for initiation (1–3). Once instituted, however, short of daily trial and error, there is little in the way of objective data to prognosticate success of weaning off ECMO and longer term survival. In this issue of Pediatric Critical Care Medicine, Punn et al (4) uses echocardiography to address the question of how to risk stratify patients with ECMO and inform the likelihood of successful separation from mechanical support. The main finding of this single-center cohort was that serial echocardiographic measurements of the velocity time integral (VTI) while trialing off ECMO identified individuals likely to tolerate separation. Patients who survived to hospital discharge increased VTI by more than 30% when transitioned from full ECMO support to a nonsupported state. Patients who died or later underwent heart transplantation did not have a statistically significant increase in VTI. Changes to other clinical and echocardiographic indicators did not differentiate those who survived from those who did not. www.pccmjournal.org
909
Extubation and Extracorporeal Membrane Oxygenation: What a Difference a Decade Makes!!* Heidi J. Dalton, MD Critical Care Medicine Phoenix Children’s Hospital Phoenix, AZ; and Child Health University of Arizona College of Medicine-Phoenix Phoenix, AZ
A
long with the rise of smartphones, apps for everything, social media, electric cars and miniaturization of items from computers to televisions, changes in the medical environment include the rise in the use of extracorporeal membrane oxygenation (ECMO) and changes in patient management associated with it. Much of the current shift in the acceptance of ECMO as a viable technique in patients with severe cardiac or respiratory failure, cardiac arrest or as a bridge to transplant has come with the changes in technology that have occurred over the past few years. Smaller and more efficient pumps, oxygenators and tubing configurations now allow ECMO to be set up, primed and ready for use almost instantaneously (1, 2). Cannulas with improved flow dynamics that can support infants through adults are available and experience gained is resulting in improved cannulation techniques and potentially safer routes for access. Along with technology, research in critical care has shown us that many “traditional” approaches to patient care may actually be harmful—from mechanical ventilation, immobility and the overuse of sedative agents designed to keep patients “comfortable” during their intensive care stay (3, 4). Maintaining sedation to the point of coma was for many years a hallmark in critically ill patients such as those receiving ECMO. Limiting metabolic demands in these critically ill patients coupled with concern over the potential adverse effects on pump flow or cannula position that would impair function of the extracorporeal support system kept many patient sedated and receiving neuromuscular blockade for days or weeks on end (5). Indeed, for patients requiring prolonged ECMO, withdrawal from narcotic medications received during ECMO kept many in the hospital long after their critical illness was resolved. As we are learning to limit such medications
*See also p. 861. Key Words: acute respiratory distress syndrome; extracorporeal membrane oxygenation; extracorporeal life support; extubation; respiratory failure Dr. Dalton lectured for rEVO Biologics and ThermoFisher and received support for the development of educational presentations from the Society of Critical Care Medicine (Pediatric Critical Care Medicine Board Review Course). Her institution received grant support from the National Institutes of Health. Copyright © 2014 by the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies DOI: 10.1097/PCC.0000000000000265
Pediatric Critical Care Medicine
in other critically ill patients, so too has ECMO seen a paradigm shift in this area. The current trend to maintain ECMO patients in as “awake” state as possible is a dramatic example of how medicine is changing. Now, the concern is not so much as how MUCH a patient is allowed to move, but whether we are letting them move ENOUGH. Just as research has shown that patients with acute respiratory distress syndrome (ARDS) have prolonged muscle weakness and disability from their ICU illness, such has been noted in ECMO patients as well (6–8). The push to enteral nutrition and away from parenteral support also is improved by limiting narcotics and allowing more normal mobility. The current emphasis on eliminating pressure ulcers in hospitalized patients is equally or more important in ECMO patients, as wounds can increase the rate of infection or bleeding in patients who are already at high risk for these events (9, 10). Clinicians have also gained knowledge, from how best to operate on ECMO despite heparinization, how to limit SOME bleeding and thrombotic complications (although this remains the most frustrating problem in extracorporeal support) and that patients CAN be moved without adverse events (11, 12). Two other important factors have also appeared: first, that patients can be maintained on ECMO for weeks to months as a bridge to transplant or recovery (13, 14); second, in patients with severely diseased lungs on adequate ECMO support, use of mechanical ventilation is not needed nor may it be useful (15). Many reports of persistent subphysiologic tidal volumes despite high inflating pressures used during ECMO have shown us how futile trying to expand non-compliant lungs is—and reports from Sweden and other sites have for years advocated that the known course of ARDS takes WEEKS to recovery and that patience is more important than attempting to maintain tidal volume during ECMO with mechanical ventilation. New reports of patients who have been bridged to lung transplant have noted that recipients who are kept awake and are able to participate in physical therapy to maintain muscle strength tend to do better than those who aren’t (16). In this issue of Pediatric Critical Care Medicine, the current report by Antón-Martín et al (17) on the success of extubation during ECMO is another ripple in the shift that is occurring with ECMO. The advantages seem obvious: the ability for a patient to spontaneously breath, provide their own pulmonary toilet, eat orally, interact with family and caregivers and participate in exercise, schoolwork and activities of daily living which may all play a part in successful recovery. While some fear that losing whatever lung expansion is being maintained with mechanical ventilator support may retard healing, provide a breeding ground for infection and reduce the ability for mechanical means of removing secretions from the airways, there is little data that this is true. Research is also finding that maintaining stretch of damaged alveoli may www.pccmjournal.org
907
Editorials
induce cytokines that result in multiple organ failure or limit recovery (18–22). The current report is an excellent demonstration of how much ECMO care has evolved over the past few years (17). It also demonstrates how much ECMO remains a “team sport” (23). One good example of this is the focused ECMO physician team who provide consultative support to the primary service team. Given the long ECMO duration and complexities of patients supported, having such a focus team can help provide continuity and offer consultation to the primary service team on issues such as timing and advisability of extubation. Involving families, nursing, respiratory and support staff in these decisions is also important to promote success. The issues raised regarding the dyspnea noted in some patients, despite seemingly adequate oxygenation and ventilation via the ECMO circuit, have been noted by others and remain mysterious and often distressing (24). Whether this is related to intrinsic stretch receptor signals coming from consolidated lungs to initiate respiratory effort and try to improve tidal volume or other factors has yet to be elucidated. In some patients, the dyspnea can be reduced by driving down the carbon dioxide level in the blood returning to the brain via the ECMO circuit and eliminating the hypercarbic drive to breathe (25). In other patients, especially small infants, the ECMO circuit is so efficient at removing carbon dioxide that the patient has NO hypercarbic drive to breathe and may appear apneic. For some patients, however, it seems as if no adjustment in the ECMO circuit can lessen the patient’s spontaneous efforts. One caveat in this circumstance is that unless the patient’s respiratory effort compromises extracorporeal pump flow, it is often more distressing to the caregivers than it is to the patient. Patient’s may report feeling “fine” even with nasal flaring and visual signs of respiratory distress. Learning to adjust to these aspects of care in an extubated ECMO patient requires buy-in from all team members, including the family. While the benefits of extubation in terms of decreased sedation, increased mobility and interaction with the environment are notable, adoption of this practice requires careful planning. As noted in the Anton-Martin report, emergent reintubation for assistance with resuscitation was required in 1 patient. Several other patients were reintubated for “recruitment”—it would be interesting to know exactly “why” these decisions were made and how long after reintubation the survivors were weaned from ECMO. Clearly, the loudest argument AGAINST extubation during ECMO comes from camps who believe that maintaining positive pressure is required to prevent complete atelectasis during ECMO and that measures to improve tidal volume, whether with airway pressure or clearance procedures are a vital part of patient care (26). Arguing against this is the lack of expansion obtained, even with high levels of ventilator support, that has been noted in patients with severe ARDS and the rationale that exposing the patient to high levels of positive pressure or repeated therapies such as bronchoscopy (unless removing mucous plugs or obstructions) or other intermittent airway clearance modalities merely encourages more cytokine formation and may place the patient at higher risk of airleak or bleeding (27). Spontaneous breathing efforts, even in 908
www.pccmjournal.org
consolidated lungs, may promote lymphatic drainage from the pulmonary bed which may be beneficial (15, 28, 29). It is evident that further research in the area of how best to “treat” the lung during ECMO for respiratory and cardiac support is needed (30). The current trend towards extubation in many centers highlights the need for a team effort with procedures and practices in place both to implement extubation safely, have readily available algorithms and equipment if reintubation is required and agreement among members that this is a goal for the patient (31, 32). As has been noted in several recent publications, titles such as “We don’t need mechanical ventilation anymore” (15), or “Extracorporeal gas exchange and spontaneous breathing as a treatment for acute respiratory distress syndrome: an alternative to mechanical ventilation?” (32), this novel approach to patient care during ECMO outlined in the current report is becoming more commonplace. Further investigation is needed to refine patient populations and management to improve outcomes. Investigation into the issues in dyspnea, which can result in interruption of pump flow from respiratory effort, are also required to allow successful use of extubation during the ECMO course.
REFERENES
1. Chai PJ, Jacobs JP, Dalton HJ, et al: Extracorporeal cardiopulmonary resuscitation for post-operative cardiac arrest: indications, techniques, controversies, and early results–what is known (and unknown). Cardiol Young 2011; 21 Suppl 2:109–117 2. Dalton HJ: Extracorporeal membrane oxygenation in the 21st century: a decade of change. Pediatr Crit Care Med 2011; 12:692–693 3. Azoulay E, Citerio G, Bakker J, et al: Year in review in Intensive Care Medicine 2013: II. Sedation, invasive and noninvasive ventilation, airways, ARDS, ECMO, family satisfaction, end-of-life care, organ donation, informed consent, safety, hematological issues in critically ill patients. Intensive Care Med 2014; 40:305–319 4. Adhikari NK, Tansey CM, McAndrews MP, et al: Self-reported depressive symptoms and memory complaints in survivors five years after ARDS. Chest 2011; 140:1484–1493 5. Andrews AF, Roloff DW, Bartlett RH: Use of extracorporeal membrane oxygenators in persistent pulmonary hypertension of the newborn. Clin Perinatol 1984; 11:729–735 6. Bartlett RH, Andrews AF, Toomasian JM, et al: Extracorporeal membrane oxygenation for newborn respiratory failure: forty-five cases. Surgery 1982; 92:425–433 7. Boykin AR, Quivers ES, Wagenhoffer KL, et al: Cardiopulmonary outcome of neonatal extracorporeal membrane oxygenation at ages 10-15 years. Crit Care Med 2003; 31:2380–2384 8. Andrews AF, Nixon CA, Cilley RE, et al: One- to three-year outcome for 14 neonatal survivors of extracorporeal membrane oxygenation. Pediatrics 1986; 78:692–698 9. Frenckner B, Ehrén H, Palmér K: Patient complications during extracorporeal membrane oxygenation (ECMO). Eur J Pediatr Surg 1991; 1:339–342 10. Bilen O, Loftis L, Teruya J: Severe thrombotic and bleeding complications in a baby with heterozygous factor V Leiden and acquired von Willebrand disease on ECMO. J Extra Corpor Technol 2011; 43:64–69 11. Haefner SM, Bratton SL, Annich GM, et al: Complications of intermittent prone positioning in pediatric patients receiving extracorporeal membrane oxygenation for respiratory failure. Chest 2003; 123:1589–1594 12. Munshi L, Fan E, Del Sorbo L: Prone position during ECMO: a turn of events? Minerva Anestesiol 2014; 80:281–283 13. Almond CS, Singh TP, Gauvreau K, et al: Extracorporeal membrane oxygenation for bridge to heart transplantation among children in the United States: analysis of data from the Organ Procurement and November 2014 • Volume 15 • Number 9
Editorials Transplant Network and Extracorporeal Life Support Organization Registry. Circulation 2011; 123:2975–2984 14. Haneya A, Philipp A, Mueller T, et al: Extracorporeal circulatory systems as a bridge to lung transplantation at remote transplant centers. Ann Thorac Surg 2011; 91:250–255 15. Del Sorbo L, Ranieri VM: We do not need mechanical ventilation any more. Crit Care Med 2010; 38:S555–S558 16. Turner DA, Cheifetz IM, Rehder KJ, et al: Active rehabilitation and physical therapy during extracorporeal membrane oxygenation while awaiting lung transplantation: a practical approach. Crit Care Med 2011; 39:2593–2598 17. Anton-Martin P, Thompson MT, Sheeran PD, et al: Extubation During Pediatric Extracorporeal Membrane Oxygenation: A Single-Center Experience. Pediatr Crit Care Med 2014; 15:861–869 18. Dixon DL, Barr HA, Bersten AD, et al: Intracellular storage of surfactant and proinflammatory cytokines in co-cultured alveolar epithelium and macrophages in response to increasing CO2 and cyclic cell stretch. Exp Lung Res 2008; 34:37–47 19. Bohrer B, Silveira RC, Neto EC, et al: Mechanical ventilation of newborns infant changes in plasma pro- and anti-inflammatory cytokines. J Pediatr 2010; 156:16–19 20. Vobruba V, Klimenko OV, Kobr J, et al: Effects of high tidal volume mechanical ventilation on production of cytokines, iNOS, and MIP-1β proteins in pigs. Exp Lung Res 2013; 39:1–8 21. Terragni PP, Del Sorbo L, Mascia L, et al: Tidal volume lower than 6 ml/kg enhances lung protection: role of extracorporeal carbon dioxide removal. Anesthesiology 2009; 111:826–835 22. Del Sorbo L, Goffi A, Ranieri VM: Mechanical ventilation during acute lung injury: current recommendations and new concepts. Presse Med 2011; 40:e569–e583 23. Turner DA, Williford WL, Peters MA, et al: Development of a collaborative program to provide extracorporeal membrane oxygenation for
adults with refractory hypoxemia within the framework of a pandemic. Pediatr Crit Care Med 2011; 12:426–430 24. Raake J, Johnson B, Seger B, et al: Extracorporeal membrane oxygenation, extubation, and lung-recruitment maneuvers as rescue therapy in a patient with tracheal dehiscence following slide tracheoplasty. Respir Care 2011; 56:1198–1202 25. Abrams DC, Brenner K, Burkart KM, et al: Pilot study of extracorporeal carbon dioxide removal to facilitate extubation and ambulation in exacerbations of chronic obstructive pulmonary disease. Ann Am Thorac Soc 2013; 10:307–314 26. Kamat PP, Popler J, Davis J, et al: Use of flexible bronchoscopy in pediatric patients receiving extracorporeal membrane oxygenation (ECMO) support. Pediatr Pulmonol 2011; 46:1108–1113 27. Bartsch H, Kössel H, Brummer G, et al: The influence of lung injury due to mechanical ventilation on the initiation of ECMO. Int J Artif Organs 1995; 18:565–568 28. Riquet M, Hidden G, Debesse B: Direct lymphatic drainage of lung segments to the mediastinal nodes. An anatomic study on 260 adults. J Thorac Cardiovasc Surg 1989; 97:623–632 29. Bobrrikov AV, Beliakov NA, Serikov VB: [Lymph flow and the vascular permeability of the lungs during spontaneous respiration and artificial pulmonary ventilation]. Anesteziol Reanimatol 1981; 3:28–32 30. Marhong JD, Telesnicki T, Munshi L, et al: Mechanical ventilation during extracorporeal membrane oxygenation. An international survey. Ann Am Thorac Soc 2014; 11:956–961 31. Duru JA, Menges T, Bodner J, et al: [Awake ECMO therapy in airway stenosis. Bronchoscopic treatment using laser resection]. Anaesthesist 2014; 63:401–405 32. Langer T, Vecchi V, Belenkiy SM, et al: Extracorporeal gas exchange and spontaneous breathing for the treatment of acute respiratory distress syndrome: an alternative to mechanical ventilation?*. Crit Care Med 2014; 42:e211–e220
Is This Heart Going to Work?* Steven Schwartz, MD Alejandro A. Floh, MD Department of Critical Care Medicine The Hospital for Sick Children Toronto, Ontario, Canada
E
xtracorporeal membrane oxygenation (ECMO) is commonly used as a short-term rescue for critically ill patients with cardiac and cardiac failure who are unable
*See also p. 870. Key Words: congenital heart disease; extracorporeal membrane oxygenation; heart failure; ventricular function Dr. Schwartz consulted for Novartis and provided expert testimony for Summers and Schwartz. His institution received grant support from the National Institutes of Health (NIH/National Heart, Lung and Blood Institutes) and the Heart and Stroke Foundation of Canada. Dr. Floh is employed by the Office of the Chief Coroner (Member of the provincial Pediatric Death Review Committee). His institution received grant support from the Pediatric Heart Network and the NIH (1-year funding for randomized study). Copyright © 2014 by the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies DOI: 10.1097/PCC.0000000000000266
Pediatric Critical Care Medicine
to meet their systemic output demands. Following initiation, patients are supported until the myocardium recovers sufficiently to allow for separation from circulatory support or they are transitioned to longer term devices while awaiting transplantation. Overall ECMO survival ranges from 35% to 60% but varies based on the indication for initiation (1–3). Once instituted, however, short of daily trial and error, there is little in the way of objective data to prognosticate success of weaning off ECMO and longer term survival. In this issue of Pediatric Critical Care Medicine, Punn et al (4) uses echocardiography to address the question of how to risk stratify patients with ECMO and inform the likelihood of successful separation from mechanical support. The main finding of this single-center cohort was that serial echocardiographic measurements of the velocity time integral (VTI) while trialing off ECMO identified individuals likely to tolerate separation. Patients who survived to hospital discharge increased VTI by more than 30% when transitioned from full ECMO support to a nonsupported state. Patients who died or later underwent heart transplantation did not have a statistically significant increase in VTI. Changes to other clinical and echocardiographic indicators did not differentiate those who survived from those who did not. www.pccmjournal.org
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