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Concept: Extracorporeal


BACKGROUND: Preoperative extracorporeal membrane oxygenation (ECMO) is a risk factor for poor outcome and currently considered a contraindication to lung transplantation. The lung allocation score system was introduced in May 2005 and prioritizes lung allocation to those with the greatest respiratory impairment. The purpose of this study is to determine whether ECMO as a bridge to lung transplantation is an acceptable option to support those in respiratory failure until donor lungs become available in the lung allocation score era. METHOD: A retrospective review of 715 consecutive lung transplants performed between May 2005 and September 2011 was conducted using a prospectively collected institutional registry database. Twenty-four lung transplants (3.4%) were performed in the 31 patients with attempted pretransplant ECMO; 7 patients who received ECMO patients did not survive or were deemed unfit for transplantation. These patients were compared with a control group of 691 patients who did not receive pretransplant ECMO. RESULTS: The duration of pretransplant ECMO was 171 ± 242 hours (median, 91 hours). Venovenous ECMO was used for respiratory failure in 15 patients, whereas venoarterial ECMO was used for circulatory collapse due to pulmonary hypertension in 9 patients. Patients in the retransplant ECMO group were younger (46 ± 15 years vs 57 ± 14 years, P < .01) compared with the control group, with no difference in recipient gender (male/female: 10/14 vs 380/311), donor age (33 ± 14 years vs 36 ± 15 years), or donor gender (male/female: 10/14 vs 352/339). Emphysema was less common (1, 4% vs 260, 38%, P < .01), and cystic fibrosis (5, 21% vs 72, 10%, P = .09), redo lung transplant (3, 13% vs 28, 4%, P = .08), and bronchiectasis (2, 8% vs 6, 1%, P = .03) were more common in the pretransplant ECMO group. Patients in the pretransplant ECMO group had a significantly higher lung allocation score (87 ± 9 vs 44 ± 15, P < .01). All patients in the pretransplant ECMO group underwent double lung transplants on pump (cardiopulmonary bypass/ECMO), and single lung transplants were performed in 171 patients (25%) and pump was used in 243 patients (35%) in the control group. The cardiopulmonary bypass time was longer in the pretransplant ECMO group (277 ± 69 minutes vs 225 ± 89 minutes, P = .02), with no difference in ischemic time (343 ± 93 minutes vs 330 ± 98 minutes, P = .54). Cadaveric lobar lung transplants were performed because of the urgency to overcome size mismatch with an oversized donor more frequently in 25% (n = 6, no mortality with the longest follow-up at 6 years) of patients in the pretransplant ECMO group versus 0.3% (n = 2) of patients in the control group (P < .01). Post-transplant ECMO was used for primary graft dysfunction in 13 patients (54%) in the pretransplant ECMO group and 41 patients (6%) in the control group (P < .01). The median hospital stay was 46 days in the pretransplant ECMO group versus 27 days in the control group (P = .16). The actuarial survivals after lung transplants at 1, 3, 6, 12, and 24 months were 96%, 88%, 83%, 74%, and 74%, respectively, in the pretransplant ECMO group, and 97%, 94%, 90%, 83%, and 74%, respectively, in the control group (P = .787). CONCLUSIONS: Although the incidence of primary graft dysfunction requiring post-transplant ECMO is higher and the hospital stay is longer in patients receiving pretransplant ECMO, the graft survival is good (2-year survival, 74%). ECMO is efficacious as a bridge to lung transplantation with good post-lung transplant outcomes.

Concepts: Pulmonology, Cystic fibrosis, Organ transplant, Pulmonary hypertension, Lung transplantation, Extracorporeal, Extracorporeal membrane oxygenation, Lung allocation score


OBJECTIVESA sternal-sparing approach for bilateral lung transplantation was recently applied to reoperative lung transplant cases and is compared with the traditional clamshell approach.METHODSA retrospective analysis of 15 consecutive reoperative bilateral lung transplants performed from January 2008 to April 2011 was conducted. Outcomes were compared between the first 11 patients who underwent the traditional clamshell and the most recent 4 patients who underwent the sternal-sparing approach.RESULTSThe indication for retransplantation was obliterative bronchiolitis in all patients. Both groups were similar with regard to age, allograft ischaemic time and operative time. Cardiopulmonary bypass was more frequent in the sternal-sparing group although required for a shorter period of time. The need for postoperative extracorporeal membrane oxygenation for primary graft dysfunction was similar in both groups. The length of ICU care and total hospitalization length of stay were similar for the sternal-sparing group compared with the traditional clamshell approach. Operative mortality and overall survival also did not differ.CONCLUSIONSReoperative bilateral lung transplantation with a sternal-sparing approach is feasible and may yield outcomes similar to those in the traditional clamshell approach. Further analysis with larger numbers of patients is warranted to delineate the benefits of this approach for patients requiring reoperative lung transplantation.

Concepts: Time, Pulmonology, Pleural effusion, Organ transplant, Cardiopulmonary bypass, Lung transplantation, Bronchiolitis obliterans, Extracorporeal


Objective:To analyze operative repair, extracorporeal membrane oxygenation (ECMO) and survival rates based on highest pre-ductal oxygen saturation (Pre-O(2)SAT) in a large infant cohort reported to Congenital Diaphragmatic Hernia Study Group Registry between 2000 and 2010.Study Design:Analyzed data included gestational age, birth weight, defect side and size, repair, ECMO use, survival and highest reported PaO(2) and Pre-O(2)SAT in first 24 h of life. We excluded 614 infants due to severe anomaly. Pre-O(2)SAT data were available for 1672 infants.Result:Among infants with highest Pre-O(2)SAT value <85%, survival (24/105=23%) and repair (55/105=52%) rates were significantly decreased compared with infants with higher values. Survival increased to 44% for infants with highest Pre-O(2)SAT<85% who underwent operative repair. Of these, 83% (20/24) required ECMO support compared with 15% (144/961) of survivors with Pre-O(2)SAT>99% (P<0.001). The lowest reported Pre-O(2)SAT with survival was 32% and for survival without ECMO was 52%.Conclusion:A reported highest Pre-O(2)SAT<85% in the first 24 h of life was not uniformly fatal; but survival of infants with Pre-O(2)SAT<85% was associated with high ECMO use and prolonged hospitalization.

Concepts: Pregnancy, Fetus, Life, Obstetrics, Pediatrics, Extracorporeal, Extracorporeal membrane oxygenation, Congenital diaphragmatic hernia


Rationale: Increasing use of extracorporeal membrane oxygenation (ECMO) for acute respiratory failure may increase resource requirements and hospital costs. Better prediction of survival in these patients may improve resource utilisation, allow risk-adjusted comparison of center-specific outcomes and help clinicians to target patients most likely to benefit from ECMO. Objectives: To create a model for predicting hospital survival at initiation of ECMO for respiratory failure. Methods: Adult patients with severe acute respiratory failure treated by ECMO from 2000 to 2012 were extracted from the Extracorporeal Life Support Organization (ELSO) international registry. Multivariable logistic regression was used to create the Respiratory ECMO Survival Prediction score (RESP-score) using bootstrapping methodology with internal and external validation. Main results: Of the 2355 patients included in the study, 1338 patients (57%) were discharged alive from hospital. The RESP-score was developed using pre-ECMO variables independently associated with hospital survival on logistic regression which included: age, immunocompromised status, duration of mechanical ventilation prior to ECMO, diagnosis, central nervous system dysfunction, acute associated non-pulmonary infection, neuro-muscular blockade agents or nitric oxide use, bicarbonate infusion, cardiac arrest, PaCO2 and peak inspiratory pressure. The ROC curve analysis of the RESP score was c=0.74, 95% Confidence Interval (0.72 - 0.76). External validation, performed on 140 patients, exhibited excellent discrimination (c=0.92 [95%CI 0.89 - 0.97]). Conclusions: The RESP-score is a relevant and validated tool to predict survival for patients receiving ECMO for respiratory failure.

Concepts: Central nervous system, Nervous system, Regression analysis, Intensive care medicine, Prediction, Prediction interval, Extracorporeal, Extracorporeal membrane oxygenation


The use of extracorporeal membrane oxygenation (ECMO) as a bridge to lung transplantation was reported for the first time more than three decades ago; nevertheless, its use in lung transplantation was largely abandoned because of poor patient survival and frequent complications. The outcomes of patients bridged to lung transplantation using ECMO have substantially improved in the last 5 years. Recent advances in extracorporeal life support technology now allow patients with end-stage lung disease to be successfully supported for prolonged periods of time, preventing the use of mechanical ventilation and facilitating physical rehabilitation and ambulation while the patients awaits lung transplantation. This review briefly describes the evolution of ECMO use in lung transplantation and summarizes the available technology and current approaches to provide ECMO support.

Concepts: Pulmonology, Medical terms, Patient, Intensive care medicine, Medical equipment, Extracorporeal, Extracorporeal membrane oxygenation, Perfusionist


We present a 16-year-old male with severe acute respiratory and renal failure as a result of Goodpasture syndrome, requiring venovenous extracorporeal membrane oxygenation (VV-ECMO) for pulmonary haemorrhage. The patient received no systemic anticoagulation for 25 of 26 ECMO days (20 days consecutively) and suffered no coagulation-related adverse events. The patient had a subtherapeutic anticoagulation profile according to recommended ECMO guidelines during most of this time. The patient made a full recovery without respiratory compromise, ECMO circuit failure, thrombotic events or the need for ongoing haemodialysis.

Concepts: Present, Time, Chronic kidney disease, Nephrology, Intensive care medicine, Glomerulonephritis, Extracorporeal, Extracorporeal membrane oxygenation


The objective of this work was to conduct pre-clinical feasibility studies to determine if a highly efficient, active-mixing, adult extracorporeal carbon dioxide removal (ECCO2R) system can safely be translated to the pediatric population. The Hemolung Respiratory Assist System (RAS) was tested in vitro and in vivo to evaluate its performance for pediatric veno-venous applications. The Hemolung RAS operates at blood flows of 350-550 ml/min and utilizes an integrated pump-gas exchange cartridge with a membrane surface area of 0.59 m2 as the only component of the extracorporeal circuit. Both acute and seven-day chronic in vivo tests were conducted in healthy juvenile sheep using a veno-venous cannulation strategy adapted to the in vivo model. The Hemolung RAS was found to have gas exchange and pumping capabilities relevant to patients weighing 3-25 kg. Seven-day animal studies in juvenile sheep demonstrated that veno-venous extracorporeal support could be used safely and effectively with no significant adverse reactions related to device operation.

Concepts: Oxygen, Carbon dioxide, Magnesium, In vivo, Carbon, In vitro, Conducting, Extracorporeal


In patients under extracorporeal membrane oxygenation (ECMO) support requiring renal replacement therapy or plasmapheresis, connecting such extracorporeal therapy device to the ECMO circuit provides many advantages compared with central venous catheterization. However, high pressures of the ECMO circuit limit the usefulness of this technique. We propose a new approach to connect extracorporeal therapy lines to the ECMO circuit. Inlet line is connected to the oxygenator, and outlet line is connected either to the femoral artery antegrade perfusion cannula in case of venoarterial ECMO or to the lateral vent of the return cannula in case of venovenous ECMO. We report the successful management of 21 patients using this connection, with much longer hemofilter average lifetime than previously reported.

Concepts: Cardiopulmonary bypass, Medical equipment, Extracorporeal, Extracorporeal membrane oxygenation


In this article we review recent advances made in the pathophysiology, diagnosis, and treatment of inhalation injury. Historically, the diagnosis of inhalation injury has relied on nonspecific clinical exam findings and bronchoscopic evidence. The development of a grading system and the use of modalities such as chest computed tomography may allow for a more nuanced evaluation of inhalation injury and enhanced ability to prognosticate. Supportive respiratory care remains essential in managing inhalation injury. Adjuncts still lacking definitive evidence of efficacy include bronchodilators, mucolytic agents, inhaled anticoagulants, nonconventional ventilator modes, prone positioning, and extracorporeal membrane oxygenation. Recent research focusing on molecular mechanisms involved in inhalation injury has increased the number of potential therapies.

Concepts: Mode, Respiratory physiology, Medical imaging, Respiratory system, Inhalation, Extracorporeal, Prone position


Venovenous extracorporeal membrane oxygenation (vv-ECMO) has been classically employed as a rescue therapy for patients with respiratory failure not treatable with conventional mechanical ventilation alone. In recent years, however, the timing of ECMO initiation has been readdressed and ECMO is often started earlier in the time course of respiratory failure. Furthermore, some centers are starting to use ECMO as a first line of treatment, i.e., as an alternative to invasive mechanical ventilation in awake, non-intubated, spontaneously breathing patients with respiratory failure (“awake” ECMO). There is a strong rationale for this type of respiratory support as it avoids several side effects related to sedation, intubation, and mechanical ventilation. However, the complexity of the patient-ECMO interactions, the difficulties related to respiratory monitoring, and the management of an awake patient on extracorporeal support together pose a major challenge for the intensive care unit staff. Here, we review the use of vv-ECMO in awake, spontaneously breathing patients with respiratory failure, highlighting the pros and cons of this approach, analyzing the pathophysiology of patient-ECMO interactions, detailing some of the technical aspects, and summarizing the initial clinical experience gained over the past years.

Concepts: Pulmonology, Patient, Intensive care medicine, Mechanical ventilation, Therapy, Technical support, Extracorporeal, Extracorporeal membrane oxygenation