Tension pneumomediastinum from opioid inhalation.

Pneumomediastinum is a rare complication of substance use, likely due to a Valsalva maneuver after drug inhalation. There are no previously documented associations between pneumomediastinum and opioid use. A 30-year-old man with a history of recent heroin and fentanyl inhalation presented to the emergency department in respiratory distress requiring intubation. His course was complicated by pneumomediastinum which subsequently developed tension physiology. He required emergent surgical decompression with a "blowhole incision" to his anterior chest. Although a rare complication of polysubstance use, pneumomediastinum can progress to tension physiology, requiring prompt diagnosis and management.

Implementation and Outcomes of a Mobile Extracorporeal Membrane Oxygenation Program in the United States During the Coronavirus Disease 2019 Pandemic.

The coronavirus disease 2019 (COVID-19) pandemic began in the United States around March 2020. Because of limited access to extracorporeal membrane oxygenation (ECMO) in the authors' region, a mobile ECMO team was implemented by April 2020 to serve patients with COVID-19. Several logistical and operational needs were assessed and addressed to ensure a successful program, including credentialing, equipment management, and transportation. A multidisciplinary team was included in the planning, decision-making, and implementation of the mobile ECMO. From April 2020 to January 2021, mobile ECMO was provided to 22 patients in 13 facilities across four southern California counties. The survival to hospital discharge of patients with COVID-19 who received mobile ECMO was 52.4% (11 of 21) compared with 45.2% (14 of 31) for similar patients cannulated in-house. No significant patient or transportation complications occurred during mobile ECMO. Neither the ECMO nor transport teams experianced unprotected exposures to or infections with severe acute respiratory syndrome coronavirus 2. Herein, the implementation of the mobile ECMO team is reviewed, and patient characteristics and outcomes are described.

Tracheostomy Is Safe During Extracorporeal Membrane Oxygenation Support.

Patients receiving extracorporeal membrane oxygenation (ECMO) often require prolonged mechanical ventilation. Providers may be reluctant to perform tracheostomies on patients during ECMO due to their tenuous clinical status and systemic anticoagulation. We report our experience with performing open and percutaneous tracheostomies on patients supported on ECMO from August 2009 to December 2017. Of the 127 patients who underwent tracheostomy during ECMO support, the median age was 42 years (interquartile range [IQR], 29-54), 99 (78%) patients had venovenous (VV) cannulation, 22 (17%) patients had venoarterial (VA) cannulation, and six (5%) patients had hybrid configurations. Percutaneous tracheostomy was performed in 110 (87%) patients. Median-activated partial thromboplastin time (aPTT) at the time of tracheostomy was 47.5 seconds (IQR, 41-57.6 seconds). The median time from ECMO initiation to tracheostomy was 7 days (IQR, 4-11 days). A total of 55 patients (43%) received packed red blood cell (pRBC) transfusions within 48 hours after tracheostomy with a median transfusion of 2 units (IQR, 1-3). There was no procedural mortality. Overall, 88 (69%) patients survived to decannulation and 74 (58%) survived to hospital discharge. Our experience with the largest published series of tracheostomies during ECMO demonstrates that excellent outcomes can be achieved without significant morbidity.

Regeneration of severely damaged lungs using an interventional cross-circulation platform.

The number of available donor organs limits lung transplantation, the only lifesaving therapy for the increasing population of patients with end-stage lung disease. A prevalent etiology of injury that renders lungs unacceptable for transplantation is gastric aspiration, a deleterious insult to the pulmonary epithelium. Currently, severely damaged donor lungs cannot be salvaged with existing devices or methods. Here we report the regeneration of severely damaged lungs repaired to meet transplantation criteria by utilizing an interventional cross-circulation platform in a clinically relevant swine model of gastric aspiration injury. Enabled by cross-circulation with a living swine, prolonged extracorporeal support of damaged lungs results in significant improvements in lung function, cellular regeneration, and the development of diagnostic tools for non-invasive organ evaluation and repair. We therefore propose that the use of an interventional cross-circulation platform could enable recovery of otherwise unsalvageable lungs and thus expand the donor organ pool.

Increasing Opportunity for Lung Transplant in Interstitial Lung Disease With Pulmonary Hypertension.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) as a bridge to lung transplantation for end-stage interstitial lung disease (ILD) and pulmonary hypertension (PH) has varying results based on ECMO configuration. We compare our experience using venovenous (VV) and venoarterial (VA) ECMO bridge to transplantation for ILD with PH on survival to successful transplantation. METHODS: A single-center retrospective review was done of patients with ILD and secondary PH who were placed on either VV or VA ECMO as bridge to transplantation from 2010 to 2016. Comparisons for factors associated with survival to transplantation between VV and VA ECMO strategies were made using Cox proportional hazards model. Subgroup analysis included comparisons of VV ECMO patients who remained on VV or were converted to VA ECMO. RESULTS: A total of 50 patients with ILD and PH were treated initially with either VV (n = 19) or VA (n = 31) ECMO as bridge to lung transplantation. Initial VA ECMO had a significantly higher survival to transplantation compared with initial VV ECMO (p = 0.03). Cox proportional hazards modeling showed a 59% reduction in risk of death for VA compared with VV ECMO (hazard reduction 0.41, 95% confidence interval: 0.18 to 0.92, p = 0.03). Patients converted from VV to VA ECMO had significantly longer survival awaiting transplant than patients who remained on VV ECMO (p = 0.03). Ambulation on ECMO before transplantation was associated with an 80% reduction in the risk of death (hazard reduction 0.20, 95% confidence interval: 0.08 to 0.48, p < 0.01). CONCLUSIONS: Venoarterial ECMO upper body configuration for patients with end stage ILD and PH significantly improves overall survival to transplantation.

Extracorporeal Membrane Oxygenation for End-Stage Interstitial Lung Disease With Secondary Pulmonary Hypertension at Rest and Exercise: Insights From Simulation Modeling.

Interstitial lung disease (ILD) represents a collection of lung disorders with a lethal trajectory with few therapeutic options with the exception of lung transplantation. Various extracorporeal membrane oxygenation (ECMO) configurations have been used for bridge to transplant (BTT), yet no optimal configuration has been clearly demonstrated. Using a cardiopulmonary simulation, we assessed different ECMO configurations for patients with end-stage ILD to assess the physiologic deficits and help guide the development of new long-term pulmonary support devices. A cardiopulmonary ECMO simulation was created, and changes in hemodynamics and blood gases were compared for different inflow and outflow anatomic locations and for different sweep gas and blood pump flow rates. The system simulated the physiologic response of patients with severe ILD at rest and during exercise with central ECMO, peripheral ECMO, and with no ECMO. The output parameters were total cardiac output (CO), mixed venous oxygen (O2) saturation, arterial pH, and O2 delivery (DO2)/O2 utilization (VO2) at different levels of exercise. The model described the physiologic state of progressive ILD and showed the relative effects of using various ECMO configurations to support them. It elucidated the optimal device configurations and required physiologic pump performance and provided insight into the physiologic demands of exercise in ILD patients. The simulation program was able to model the pathophysiologic state of progressive ILD with PH and demonstrate how mechanical support devices can be implemented to improve cardiopulmonary function at rest and during exercise. The information generated from simulation can be used to optimize ECMO configuration selection for BTT patients and provide design guidance for new devices to better meet the physiologic demands of exercise associated with normal activities of daily living.

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.

The "Central Sport Model": Extracorporeal Membrane Oxygenation Using the Innominate Artery for Smaller Patients as Bridge to Lung Transplantation.

Venoarterial extracorporeal membrane oxygenation (VA ECMO) may be used in patients with advanced cardiac or pulmonary failure. Arterial cannulation via the femoral arteries is suboptimal in many clinical scenarios because of associated complications and the potential for differential hypoxemia between the upper and lower body. To address these concerns, we typically use an upper body configuration (sport model) with right internal jugular and axillary or subclavian artery cannulation to allow a safe and durable means of providing VA ECMO support without differential hypoxemia. Unfortunately, this approach may not be feasible in smaller patients, whose vessels may preclude optimal use of the axillary or subclavian arteries and in those with systemic vasculopathy associated with connective tissue disorders. We describe a new approach for patients of small stature using the innominate artery through a mini-upper sternotomy in seven patients.