ECMO in trauma care: What you need to know.

ABSTRACT: Over the past 10 years, extracorporeal membrane oxygenation (ECMO) use in trauma patients has increased significantly. This includes adult and pediatric trauma patients and even combat casualties. Most ECMO applications are in a venovenous (VV ECMO) configuration for acute hypoxemic respiratory failure or anatomic injuries that require pneumonectomy or extreme lung rest in a patient with insufficient respiratory reserve. In this narrative review, we summarize the most common indications for VV ECMO and other forms of ECMO support used in critically injured patients, underscore the importance of early ECMO consultation or regional referral, review the technical aspects of ECMO cannulation and management, and examine the expected outcomes for these patients. In addition, we evaluate the data where it exists to try to debunk some common myths surrounding ECMO management.

A Case Report of Combat Blast Injury Requiring Combat Casualty Care, Far-Forward ECMO, Air Transport, and All Levels of Military Critical Care.

We describe a 34-year-old soldier who sustained a blast injury in Syria resulting in tracheal 5 cm tracheal loss, cervical spine and cord injury with tetraplegia, multiple bilateral rib fractures, esophageal injury, traumatic brain injury, globe evisceration, and multiple extremity soft tissue and musculoskeletal injuries including a left tibia fracture with compartment syndrome. An emergent intubation of the transected trachea was performed in the field, and the patient was resuscitated with whole blood prehospital. During transport to the Role 2, the patient required cardiopulmonary resuscitation for cardiac arrest. On arrival, he underwent a resuscitative thoracotomy and received a massive transfusion exclusively with whole blood. A specialized critical care team transported the patient to the Role 3 hospital in Baghdad, and the DoD extracorporeal membrane oxygenation (ECMO) team was activated secondary to his unstable airway and severe hypoxia secondary to pulmonary blast injury. The casualty was cannulated in Baghdad approximately 40 hours after injury with bifemoral cannulae in a venovenous configuration. He was transported from Iraq to the U.S. Army Institute of Surgical Research Burn Center in San Antonio without issue. Extracorporeal membrane oxygenation support was successfully weaned, and he was decannulated on ECMO day 4. The early and en route use of venovenous ECMO allowed for maintenance of respiratory support during transport and bridge to operative management and demonstrates the feasibility of prolonged ECMO transport in critically ill combat casualties.

Management of Surge in Extracorporeal Membrane Oxygenation Transport.

BACKGROUND: Transporting patients receiving extracorporeal membrane oxygenation (ECMO) support is safe and reliable with a dedicated program and established management protocols. As our program has grown, our teams have had to adapt to manage surges in transport volume while maintaining patient safety. We assessed the outcomes at peak use of our ECMO transport services during surges. METHODS: We conducted a single-center retrospective review of all patients transported to our institution while supported with ECMO from September 2008 to September 2016. Survival to discharge was the primary outcome. Surge patients were defined as those transported during months with at least 8 transports or patients transported within 24 hours of another patient in nonsurge months. RESULTS: From 2008 to 2016, 222 patients were transported to our institution while supported with ECMO. Baseline characteristics and indices of disease severity were comparable between surge and nonsurge patients. Of the 84 patients transported during surges, 59 surge patients (70%) survived to hospital discharge vs 86 (63%) of nonsurge patients (p = 0.31). Multivariable logistic regression showed that age and APACHE II (Acute Physiology and Chronic Health Evaluation) severity index score were predictors of in-hospital death (p < 0.05), but transportation during a surge was not (odds ratio, 0.91; 95% confidence interval, 0.46 to 1.80; p = 0.79). CONCLUSIONS: Patient safety and clinical outcomes can be maintained during surges in ECMO transport volume if the ECMO program has developed plans for handling transient increases in volume and considers staff fatigue and burnout. Standardizing interhospital communication, patient selection, and management protocols are critical to maintaining quality of care.

Morbid obesity is not a contraindication to transport on extracorporeal support.

OBJECTIVES: Extracorporeal membrane oxygenation (ECMO) transport has not been described in morbidly obese patients, a population that can pose significant challenges in obtaining vascular access, indexed flows and transport logistics. We sought to study the feasibility and safety of transporting obese and morbidly obese patients during extracorporeal support. METHODS: We conducted a retrospective review of all patients transported to our institution while receiving ECMO from September 2008 to September 2016. Survival to decannulation and survival to discharge were the primary outcomes. Obesity and morbid obesity were defined as a body mass index of greater than 30 kg/m2 and greater than 40 kg/m2, respectively. RESULTS: From 2008 to 2016, 222 patients were transported to our institution while receiving ECMO. Among these included patients, 131 were non-obese (interquartile range 22-27 kg/m2), 63 were obese (interquartile range 31-35 kg/m2) and 28 were morbidly obese (interquartile range 41-49 kg/m2), with 6 patients having a body mass index greater than 50 kg/m2 (range 52.3-79 kg/m2). Pre-ECMO arterial blood gases, disease severity indices, cannulation strategies and transport distances were similar between these 3 groups. There was no mortality of patients during transport, and survival to discharge was 66% (n = 87) in non-obese patients, 56% (n = 35) in obese patients and 82% (n = 23) in morbidly obese patients (P = 0.042). On multivariable logistic regression analysis, body mass index was not a predictor of in-hospital mortality (odds ratio 0.99, 95% confidence interval 0.95-1.03; P = 0.517). CONCLUSIONS: Transport of morbidly obese patients receiving ECMO may be performed safely and with excellent results in the setting of a dedicated ECMO transport programme with well-established management protocols.

Functional vascularized lung grafts for lung bioengineering.

End-stage lung disease is the third leading cause of death worldwide, accounting for 400,000 deaths per year in the United States alone. To reduce the morbidity and mortality associated with lung disease, new therapeutic strategies aimed at promoting lung repair and increasing the number of donor lungs available for transplantation are being explored. Because of the extreme complexity of this organ, previous attempts at bioengineering functional lungs from fully decellularized or synthetic scaffolds lacking functional vasculature have been largely unsuccessful. An intact vascular network is critical not only for maintaining the blood-gas barrier and allowing for proper graft function but also for supporting the regenerative cells. We therefore developed an airway-specific approach to removing the pulmonary epithelium, while maintaining the viability and function of the vascular endothelium, using a rat model. The resulting vascularized lung grafts supported the attachment and growth of human adult pulmonary cells and stem cell-derived lung-specified epithelial cells. We propose that de-epithelialization of the lung with preservation of intact vasculature could facilitate cell therapy of pulmonary epithelium and enable bioengineering of functional lungs for transplantation.

Awake Extracorporeal Membrane Oxygenation as Bridge to Lung Transplantation: A 9-Year Experience.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) is used as a bridge to lung transplantation, but characteristics that influence its success are poorly understood. This large, single-center experience evaluated the implementation and outcomes of ECMO in this setting. METHODS: Data were collected for patients at our institution (New York-Presbyterian Hospital/Columbia University Medical Center in New York) who received ECMO as a bridge to lung transplantation from January 1, 2007 through July 10, 2016. Data were analyzed for demographics, baseline characteristics, survival, and ECMO configuration. RESULTS: Seventy-two patients received ECMO as a bridge to lung transplantation. Of the 72 patients, 40 (55.6%) underwent the transplantation procedure, 37 (92.5%) survived to discharge, and 21 (84.0%) survived for 2 years. Inotropy or vasopressor support (70% vs 93.8%; p = 0.011), Simplified Acute Physiology Score (26.8 vs 30.5; p = 0.048), and ambulation (80% vs 56.2%; p = 0.030) were significantly different between the patients who underwent lung transplantation and those who did not. Patients with cystic fibrosis were more likely to have a bridge to transplantation than patients with other lung diseases (47.5% vs 25%; p = 0.050). Daily participation in physical therapy was achieved in 50 patients (69.4%). CONCLUSIONS: This study demonstrated favorable survival in patients receiving ECMO as a bridge to lung transplantation and achieved high rates of physical therapy and avoidance of mechanical ventilation while ECMO was used in patients awaiting lung transplantation. With more than half of these patients successfully bridged to lung transplantation, we gained insight into the factors influencing patients' outcomes, including patient selection, timing of ECMO, and patient management.

Extracorporeal Membrane Oxygenation for Cardiopulmonary Failure During Pregnancy and Postpartum.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) has been used with increasing frequency to support pregnant and postpartum patients with severe cardiac or pulmonary failure, although patient management and clinical outcomes are underreported. This study represents patients who received ECMO during the peripartum period. METHODS: All pregnant or postpartum patients treated with ECMO in the medical intensive care unit between January 1, 2009, and June 30, 2015, were included in this study. Data were analyzed retrospectively. The primary objective was to characterize the circumstances and clinical characteristics of the patients who received ECMO, describe our management during pregnancy and at the time of delivery, evaluate maternal and fetal outcomes, and report bleeding and thrombotic complications. RESULTS: Eighteen peripartum patients were treated with ECMO during the study period; 4 were pregnant at the time of cannulation. Median age was 32.6 years, and median gestational age in pregnant patients was 32 weeks. Sixteen patients (88.9%) survived to hospital discharge. Fetal survival was 14 (77.8%) in the entire cohort and 100% in patients cannulated after fetal viability. Two patients successfully delivered on ECMO. Bleeding complications developed in 6 patients (33.3%) and were associated with disseminated intravascular coagulation. No fetal complications were attributed to ECMO. CONCLUSIONS: ECMO can be used during pregnancy and postpartum with favorable maternal and fetal outcomes, and it outweighs the risk of bleeding or thrombotic complications when managed by an experienced, multidisciplinary team.

One Hundred Transports on Extracorporeal Support to an Extracorporeal Membrane Oxygenation Center.

BACKGROUND: Extracorporeal life support technology has gained acceptance as a salvage mode for patients in respiratory or cardiac failure. Patients who are sick enough to require extracorporeal membrane oxygenation (ECMO) support are often too unstable for transfer to a hospital with ECMO capabilities. We highlight the progressive development of an ECMO transport team and the manner in which it provides reliable transport with excellent outcomes. METHODS: All data were collected retrospectively from our hospital's electronic medical record. Patient outcomes are reported through April 2, 2014. RESULTS: Our institution began an ECMO transport program in 2008, with the initial phase involving transport of highly selected patients for short distances. With experience we refined our intake and evaluation process. We also consolidated care for ECMO patients into two intensive care units and developed a dedicated ECMO intensivist position. As the program has matured, patient selection has become more inclusive and we have extended our capabilities to include interstate and international transport. All 100 patients were successfully placed on ECMO and transported to our center. Seventy-nine patients were placed on venovenous ECMO, 19 on venoarterial ECMO, and 2 on venovenous arterial ECMO. The median transport distance was 16 miles and ranged from 2.5 to 7,084 miles. CONCLUSIONS: Extracorporeal membrane oxygenation transport can be performed safely and reliably with excellent outcomes with a dedicated team that maintains stringent adherence to well-designed management protocols.

ECMO as bridge to lung transplant.

Since the advent of lung transplantation more than 5 decades ago, preoperative, surgical, and anesthetic management have improved. The growing experience with extracorporeal membrane oxygenation (ECMO) has enabled clinicians to expand its effective use to care for patients while bridging them to transplant (BTT). We highlight the approach in which ECMO is used to successfully bridge critically ill patients to lung transplantation when stringent daily clinical assessment is applied. In patients who continued to meet transplant criteria and were successfully transplanted, postoperative survival rates are acceptable. Larger studies are needed to inform decision algorithms for BTT patients and optimize outcomes.

Comparison of extracorporeal membrane oxygenation versus cardiopulmonary bypass for lung transplantation.

OBJECTIVE: This study compared differences in patient outcomes and operative parameters for extracorporeal membrane oxygenation (ECMO) versus cardiopulmonary bypass (CPB) in patients undergoing lung transplants. METHODS: Between January 1, 2008, and July 13, 2013, 316 patients underwent lung transplants at our institution, 102 requiring intraoperative mechanical cardiopulmonary support (CPB, n=55; ECMO, n=47). We evaluated survival, blood product transfusions, bleeding complications, graft dysfunction, and rejection. RESULTS: Intraoperatively, the CPB group required more cell saver volume (1123±701 vs 814±826 mL; P=.043), fresh-frozen plasma (3.64±5.0 vs 1.51±3.2 units; P=.014), platelets (1.38±1.6 vs 0.43±1.25 units; P=.001), and cryoprecipitate (4.89±6.3 vs 0.85±2.8 units; P<.001) than the ECMO group. Postoperatively, the CPB group received more platelets (1.09±2.6 vs 0.13±0.39 units; P=.013) and was more likely to have bleeding (15 [27.3%] vs 3 [6.4%]; P=.006) and reoperation (21 [38.2%] vs 7 [14.9%]; P=.009]. The CPB group had higher rates of primary graft dysfunction at 24 and 72 hours (41 [74.5%] vs 23 [48.9%]; P=.008; and 42 [76.4%] vs 26 [56.5%]; P=.034; respectively). There were no differences in 30-day and 1-year survivals. CONCLUSIONS: Relative to CPB, the ECMO group required fewer transfusions and had less bleeding, fewer reoperations, and less primary graft dysfunction. There were no statistically significant survival differences at 30 days or 1 year.

The "sport model": extracorporeal membrane oxygenation using the subclavian artery.

Venoarterial extracorporeal membrane oxygenation is used for patients with refractory cardiopulmonary failure. Arterial cannulation by means of femoral arteries is fraught with potential complications. We present a technique for subclavian artery cannulation to provide a safe and durable means of venoarterial extracorporeal membrane oxygenation support.