Venovenous Extracorporeal Membrane Oxygenation Support Research Articles

Physiotherapy for Patients on Awake Extracorporeal Membrane Oxygenation: A Systematic Review.

Extracorporeal membrane oxygenation (ECMO) is used as temporary life support in subjects with potentially reversible respiratory/cardiac failure. The principal purpose of this review was to assess the characteristics and potential advantages of physiotherapeutic interventions in subjects on awake ECMO support. Seven databases were interrogated: we searched titles, abstracts and keywords using the Medical Subject Headings terms 'extracorporeal membrane oxygenation' and 'rehabilitation' linked with the Boolean operator 'AND'. In total, 216 citations were retrieved. Nine citations satisfied our inclusion criteria and were subjected to full-text analysis. The numbers of patients enrolled in the included studies (most of which were case series) were low (n = 52). We found no prospective studies or randomized controlled trials. Overall, subjects on awake ECMO usually received a combination of passive and active physiotherapy, and most achieved an acceptable degree of autonomy after treatment. Emerging research in the field affords preliminary evidence supporting the safety of early mobilization and ambulation in patients on awake veno-venous ECMO support. Copyright © 2015 John Wiley & Sons, Ltd.

Safety of recombinant factor VIIa in patients under extracorporeal membrane oxygenation

To address the safety (rate of thromboembolic events and circuit complications) and efficacy (rate of bleeding control) of recombinant activated coagulation factor VII (rFVIIa) to treat severe bleeding refractory to all surgical and medical treatments in patients under veno-arterial (VA) or veno-venous (VV) extracorporeal membrane oxygenation (ECMO) support. In a tertiary referral University Cardiothoracic Surgery Centre including three intensive care units, 30 patients received the rFVIIa during ongoing VA or VV ECMO support (8.6% of ECMO activity from 2005 to 2014; N = 347). Early and late clinical results were analysed (retrospective analysis of prospectively collected data). In a substudy, a case-matching procedure was performed among ECMO patients who received (Group A) or did not receive (Group B) rFVIIa treatment. The mediastinum was the most common site of refractory bleeding (after heart transplantation or other cardiac surgery; 90%); 90% (n = 27) of patients were on VA ECMO and the remainder on VV ECMO. The survival rate at ECMO explantation and at the 30th post-implantation day was 67 and 50%, respectively. The final efficacy rate of rFVIIa in stopping bleeding was 93.3%. The rate of thromboembolic events was 3.3% (1 case) and the rate of circuit change was 16.7% (without instances of overt circuit clotting). After case-matching, Group A comprised 23 patients and Group B included 43 patients. No statistically significant differences were observed among groups in terms of thromboembolic events (P = 0.99), circuit change, ventilation time (P = 0.71), infectious complications (P = 06) and survival at both ECMO explantation and the 30th post-implantation day. Late survival was comparable (Kaplan-Meier analysis; P = 0.42). In case of life-threatening bleeding refractory to all conventional therapies, rFVIIa presents an acceptable safety profile in patients under ECMO support. No circuit dysfunctions and limited rates of thromboembolism are observed.

Effects on membrane lung gas exchange of an intermittent high gas flow recruitment maneuver: preliminary data in veno-venous ECMO patients.

Gas exchange capabilities of polymethylpentene membrane lungs (MLs) worsen over time. ML deterioration is related to protein deposit and clot formation. Condensation and trapping of water vapor inside ML hollow fibers might affect ML performances as well. Increasing sweep gas flow (GF) could remove such fluid. The purpose of this study was to evaluate the effects on ML gas exchange of a recruitment maneuver (RM) based on a brief increase in GF, during veno-venous ECMO support. Short-term (15min) effects of 20 RMs were assessed. RM raised ML CO2 removal from 149±37 to 174±41ml/min (p<0.001). Conversely, RM did not improve ML O2 transfer (155±31 and 158±31ml/min before and after RM, respectively). ML outlet pCO2 decreased after RM from 51.2±5.8 to 45.8±5.4mmHg (p<0.001), while ML outlet pO2 increased from 520±61 to 555±51mmHg (p<0.001). Both ML dead space and shunt fractions decreased from 47.8±15.3 to 29.6±14.7% (p<0.001) and from 8.8±4.2 to 7.0±3.8% (p<0.001), respectively. Furthermore, a subset of 5 RMs was evaluated on a 6-h time frame. The beneficial effects on ML performances due to the RM gradually diminished and waned over a 6-h interval after the RM. The RM improved ML CO2 removal substantially, albeit temporarily. ML oxygenation performance was marginally affected.

Veno-veno-arterial extracorporeal membrane oxygenation for respiratory failure with severe haemodynamic impairment: technique and early outcomes.

Patients with respiratory failure may benefit from veno-venous and veno-arterial extracorporeal membrane oxygenation (ECMO) support. We report on our initial experience of veno-veno-arterial (v-v-a) ECMO in patients with respiratory failure. Between January 2012 and February 2014, 406 patients required ECMO support at our institution. Here, we retrospectively analysed the characteristics and outcomes of patients commenced on either veno-venous or veno-arterial ECMO due to respiratory failure, and then switched to v-v-a ECMO. Ten (2%) patients proceeded to v-v-a ECMO. The underlying conditions were acute respiratory distress syndrome (n = 3), end-stage pulmonary fibrosis (n = 5) and respiratory failure after major thoracic surgery (n = 1) and Caesarean section (n = 1). In all of these patients, ECMO was initially started as veno-venous (n = 9) or veno-arterial (n = 1) ECMO but was switched to a veno-veno-arterial (v-v-a) approach after a mean of 2 (range, 0-7) days. Reasons for switching were: haemodynamic instability (right heart failure, n = 5; pericardial tamponade, n = 1; severe mitral valve regurgitation, n = 1; haemodynamic instability following cardiopulmonary resuscitation, n = 1 and evidence of previously unknown atrial septal defect with pulmonary hypertension and Eisenmenger syndrome, n = 1) and upper-body hypoxaemia (n = 1). ECMO-related complications were bleeding (n = 3) and leg ischaemia (n = 2). Seven patients were successfully taken off ECMO with 4 being bridged to recovery and a further 3 to lung transplantation after a mean of 11 (range, 9-18) days. Five patients survived until hospital discharge and all of them were alive at the end of the follow-up. Veno-veno-arterial ECMO is a technically feasible rescue strategy in treating patients presenting with combined respiratory and haemodynamic failure.

Is Veno-venous ECMO Support Indicated in Hypoxic Patients Post Resuscitation with Compromised Circulation?

Is Veno-venous ECMO Support Indicated in Hypoxic Patients Post Resuscitation with Compromised Circulation?

Extracorporeal Membrane Oxygenation: Past, Present and Future

Extracorporeal membrane oxygenation (ECMO) was originated from heart-lung machine for cardiac surgery. This technique that receive the blood from venous system, oxygenate it and support to selected patients with severe respiratory or cardiac failure as flow and oxygen. ECMO can provide partial or total support, is temporary, and requires systemic anticoagulation. ECMO controls gas exchange and perfusion, stabilizes the patient physiologically, decreases the risk of ongoing iatrogenic injury, and allows enough time for decision, diagnosis, treatment, and recovery from the primary injury or disease. The two major ECMO modalities are venoarterial and venovenous. Until 1980s, ECMO usually used to pediatric respiratory failure. However after H1N1 influenza epidemic in the world, venovenous ECMO support for adult has been increased rapidly. Venoarterial ECMO support for cardiac failure and resuscitation also abruptly has been increased. As a support modality, cannula position and possibility of complication is different. Survival rate of ECMO has a range from 30% in extracorporeal cardiopulmonary resuscitation to 70% for acute myocarditis and acute respiratory distress syndrome in adult, and better in neonate and pediatrics. Advancing ECMO technology and increasing experience with ECMO techniques have improved patient outcomes, reduced complications and expanded the potential applications of ECMO. Awareness of the indications and implications of ECMO among physicians managing patients with severe but potentially reversible respiratory or cardiac failure may help facilitate better communication between health care teams and improve patient recovery. (Korean J Med 2015;88:651-657)

Successful use of extracorporeal membrane oxygenation in a human immunodeficiency virus infected patient with severe acute respiratory distress syndrome.

IntroductionWe report a case of an adult patient with human immunodeficiency virus (HIV), acute respiratory distress syndrome (ARDS) and ventilator associated pneumonia (VAP) caused by multidrug resistant (MDR) bacteria that was successfully managed with veno-venous extracorporeal membrane oxygenation (ECMO).Case reportA 25 year old male with no significant past medical history had been admitted to a local hospital due to dyspnea and fever. His pulmonary function subsequently failed necessitating mechanical ventilation (MV) and introduction of ECMO support. The patient was transported for 300 km by road on ECMO to a tertiary medical center. The diagnosis of ARDS, HIV infection and MDR bacterial and fungal VAP was made. Patient was successfully treated with antiretroviral therapy (ART), anti-infective agents and 58 days of veno-venous ECMO support, with complete resolution of the respiratory symptoms.ConclusionHIV infected patients with ARDS and MDR bacterial VAP whose HIV replication is controlled by ART could be successfully managed with ECMO.

Relationship between hemoglobin concentration and extracorporeal blood flow as determinants of oxygen delivery during venovenous extracorporeal membrane oxygenation: a mathematical model.

During veno-venous extracorporeal membrane oxygenation (VV-ECMO) support, optimization of oxygenation can be achieved by therapeutic interventions on both patient physiological variables and adjustment of ECMO settings. Based on the physiology of oxygen delivery during VV-ECMO support, we established the mathematical relationship between the variables which define the oxygenation state: hemoglobin (Hb), extracorporeal blood flow (ECBF), cardiac output (Q), and systemic oxygen consumption (VO2). Assuming constant values for Q and VO2, the model was applied to elucidate the interplay between Hb and ECBF in determining arterial oxygen saturation (SaO2), and the resultant systemic oxygen delivery (DO2) and native venous oxygen saturation (SvO2) in static conditions. At constant VO2 and Q, an inverse relationship exists between Hb and ECBF in determining SaO2 and SvO2. Despite the same value of SaO2, the DO2 resulting from the different combinations of Hb and ECBF progressively decreases with decreasing Hb. By demonstrating the quantitative relationship between Hb and ECBF as determinants of oxygenation during VV-ECMO support, this mathematical model could provide a theoretical basis for a rational approach to strategies to optimize oxygenation in patients on VV-ECMO.

Three-year experience of using venovenous extracorporeal membrane oxygenation for patients with severe respiratory failure.

To present the 3-year experience of using venovenous extracorporeal membrane oxygenation for patients with severe respiratory failure in a single centre in Hong Kong. Case series. A 19-bed Intensive Care Unit of a tertiary hospital in Hong Kong. All patients who were managed with venovenous extracorporeal membrane oxygenation from 1 July 2010 to 30 June 2013 in the Intensive Care Unit. Overall, 31 patients (mean age, 42.2 years, standard deviation, 14.1 years; 21 males) received venovenous extracorporeal membrane oxygenation for the treatment of severe respiratory failure. Of these, 90.3% (28 patients) presented with pneumonia as the cause of the respiratory failure, and 22 of them had identifiable causes. A total of nine (29.0%) patients were diagnosed to have H1N1 infection. The median Murray score was 3.5 (interquartile range, 3.0-3.5); the median duration of venovenous extracorporeal membrane oxygenation support was 5.0 (2.8-8.6) days; and the median duration of mechanical ventilator support was 18.2 (7.8-27.9) days. The overall intensive care unit mortality was 19.4% (n=6). The overall in-hospital mortality and the 28-day mortality were both 22.6% (n=7). Among the 22 patients who had identifiable infective causes, those suffering from viral infection had lower intensive care unit and hospital mortality than those who had bacterial infection (8.3% vs 20.0%). All the H1N1 patients survived. Complications related to extracorporeal membrane oxygenation included severe bleeding (n=2; 6.5%) and mechanical complications of the circuits (n=3; 9.7%). Venovenous extracorporeal membrane oxygenation is an effective adjunctive therapy and can be used as a life-saving procedure for carefully selected patients with severe acute respiratory distress syndrome when the limits of standard therapy have been reached.

Surgical extraction after thrombosis around the Avalon dual lumen cannula

The use of a dual lumen cannula (DLC) for venovenous extracorporeal membrane oxygenation (ECMO) has several advantages and reports of complications are rare. We present a case of thrombosis around and inside the Avalon Elite™ bicaval DLC (Avalon Laboratories, Rancho Dominguez, CA, US), for which simple removal by retraction was impossible.A 30-year-old man had experienced an unstable C6/7 fracture with spinal contusion and haematoma in the spinal canal with incomplete neurological paraplegia and thoracic trauma. He developed acute respiratory failure due to posttraumatic systemic inflammatory response syndrome and venovenous extracorporeal membrane oxygenation (ECMO) support was indicated. The cannulation was performed with an Avalon Elite™ cannula (31Fr) in the right jugular vein under fluoroscopy. After 18 days of ECMO therapy, despite the continuous administration of heparin (400iu/h), ECMO was discontinued because of the formation of a massive thrombus in the oxygenator. At that time, the patient’s haemodynamic and respiratory parameters were stable, and we were able to induce a rapid weaning from ECMO. The surgical removal of the cannula became necessary and was performed using a small neck incision without complications.We report this case to emphasise that any resistance encountered during an attempt to extract the Avalon Elite™ cannula may cause serious complications. In such cases, surgical removal must be considered.

Initial Experience With Single-Vessel Cannulation for Venovenous Extracorporeal Membrane Oxygenation in Pediatric Respiratory Failure*

Venovenous extracorporeal membrane oxygenation has been used to provide cardiopulmonary support in critically ill infants and children. Recently, dual-lumen venovenous extracorporeal membrane oxygenation has gained popularity in the pediatric population. Herein, we report our institutional experience using a bicaval dual-lumen catheter for pediatric venovenous extracorporeal membrane oxygenation support, which has been our unified approach for venovenous extracorporeal membrane oxygenation since 2009. This study is a retrospective review. The setting is a tertiary children's hospital in a major metropolitan area. Between 2009 and 2011, 11 patients were cannulated using a dual-lumen bicaval venous catheter. Patient demographics, cannulation details, circuit complications, complications of catheter use, and patient outcomes were collected from a retrospective chart review. None. Eleven of the patients were cannulated for venovenous extracorporeal membrane oxygenation using the dual-lumen bicaval cannula. The median age at the time of venovenous cannulation was 1.9 years (range, 0.14-17.1), and the median weight was 10.2 kg (range, 3-84). Three patients (27%) required conversion to venoarterial extracorporeal membrane oxygenation. The median duration of extracorporeal membrane oxygenation support was 10 days (2-38 days). Fifty-five percent of patients suffered from a bleeding complication (disseminated intravascular coagulation, pulmonary hemorrhage, or intraventricular hemorrhage), and 45% had a circuit complication. Adequate flow rates were achieved in all patients. The overall hospital mortality in the series was 55%. There were no cannula-related complications. This review presents the first single-institution experience with the dual-lumen Avalon cannula in pediatric patients. Preliminary results indicate that the catheter can be safely placed and has an acceptable complication profile; however, continued study within larger trials is necessary to fully ascertain the clinical profile of this catheter.

Outcomes of Long-Term Veno-Venous Extracorporeal Membrane Oxygenation Support for Acute Respiratory Distress Syndrome

Purpose Given substantial advances in veno-venous extracorporeal membrane oxygenation (ECMO) technology, long-term support is increasingly feasible. Although the benefits of short-term ECMO as a bridge to recovery in acute respiratory distress syndrome (ARDS) are well described in the literature, the outcomes of patients requiring long-term support remain unclear. Methods and Materials Patients requiring ECMO for ARDS between January 2009 and November 2012 were retrospectively reviewed and analyzed separately for those requiring short-term and long-term ECMO support (≥3 weeks). Demographics, ECMO variables and outcomes of patient bridged to recovery or transplantation were assessed. Results 57 patients with ARDS were placed on ECMO during that time period with 11 patients requiring long-term ECMO support (59±51 days). Recovery was the goal in all patients. In the long-term support group, pre-ECMO mechanical ventilation was conventional PC or PRVC (N=4), APRV (N=5), or HFO (N=2). The mean pre-ECMO FiO2 was 0.93±0.13 with mean pH, PaO2, and PaCO2 of 7.3±0.1, 69±26 mmHg, 63±21 mmHg, respectively. Pre-ECMO Murray Scores were 3.7±0.4 and 3.82±0.29 (p=NS) in the long-term and short-term groups, respectively. 8 (73%) long-term support patients were successfully bridged to recovery and 1 patient was bridged to transplantation after a refractory course. 25 (52%) short-term support patients and 8 (73%) long-term support patients survived to 30-days or hospital discharge. In the long-term support group, 4 of the 8 surviving patients had mid-term follow-up available; with 100% surviving, returned to home, and with normal functional status at 1 year. Conclusions Previously, long-term ECMO support has not been thought to be associated with favorable outcomes. This study, however, may provide support for the efficacy of ECMO for patients even requiring support greater than 3 weeks as a bridge to recovery or transplantation.

Anesthetic management including extracorporeal membrane oxygenation therapy of liver transplant recipient with life-threatening hypoxemia -a case report-

We present a rare case of successful anesthetic management for a patient who had refractory hypoxia during liver transplantation (LT) with intraoperative veno-venous (VV) extracorporeal membrane oxygenation (ECMO) support. A 49 year-old female patient underwent living donor LT. After reperfusion of the grafted liver, graft congestion and massive oozing developed. Thus it was decided to reoperate with a temporary gauze packing. However, the patient's condition deteriorated with azotemia and severe hypoxemia. VV ECMO with continuous renal replacement therapy was started 24 hours before secondary LT and maintained during secondary LT. VV ECMO was weaned 32 hours after secondary LT. This case indicates that not only after the LT but also before and during LT, VV ECMO can be a treatment option for the patient with end-stage liver disease combined with respiratory failure when there is the possibility of lung recovery.

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Introduction: Centrifugal blood pumps are being increasingly used to support adults requiring veno-venous (VV) extracorporeal membrane oxygenation support (ECMO). Hypothesis: Our aim was to determine if survival and ECMO related morbidities between adults undergoing VV ECMO differed by pump type. Methods: Adults > 18 years old who underwent VV ECMO support (n = 1585) during 2005 – 2011 and reported to the ECMO registry of the Extracorporeal Life Support Organization with inclusion of pump identity. Data were limited to VV mode and for those patients who underwent more than 1 run of ECMO, only data from the first run was analyzed (n = 907). Using Greedy 1:1 propensity score matching of pre-ECMO characteristics, we compared ECMO-related outcomes in adults supported with centrifugal versus roller style pumps. Results: A total of 406 patients (203 in per pump type) were included. There were no significant differences in pre-ECMO related variables. Adults supported with centrifugal pumps had increased odds of hemolysis OR=5.4 [95% CI 2.3 – 12.6], however, had a decreased odds of diagnosis of surgical bleeding OR=0.51 [0.28 – 0.93] and diagnosis of pneumothorax OR=0.49 [0.26 – 0.93]. There was no difference in odds of acute renal injury between pump type. Survival did not differ between groups. Conclusions: In a propensity score matched cohort of adult ECMO patients, adults supported with centrifugal pumps had increased odds of hemolysis. However there was no difference in odds of renal injury or survival between pump type.

High incidence of upper-extremity deep vein thrombosis with dual-lumen venovenous extracorporeal membrane oxygenation

Venovenous extracorporealmembrane oxygenation (ECMO) has emerged as an important intervention for patients with acute respiratory failure, as well as as a bridge to lung transplantation for end-stage lung disease. A recently introduced bicaval, dual-lumen cannula appears to be a promising technologic advancement for venovenous ECMO support. Introduced percutaneously through the right internal jugular or left subclavian vein, the Avalon Elite cannula (Avalon Laboratories, Rancho Dominguez, Calif) selectively drains venous blood from the inferior and superior venae cavae and infuses oxygenated blood directly into the right atrium. Advantages of this cannula include a single insertion and upper body placement, which can allow ambulation to maintain patient conditioning.Although the cannula is available inmultiple sizes (23-31F), clinical experience has shown that larger cannula sizes are required to generate adequate flow for respiratory support in adults (>4.0 L/min). Larger cannulas used for extended durations, however, probably predispose the patient toward upper-extremity deep venous thrombosis (DVT). We evaluated the incidence and subsequent clinical implications of upper extremity DVT in patients who were supported with venovenous ECMO by means of the Avalon dual-lumen cannula.

Extracorporeal Membrane Oxygenation Support in a Patient with Status Asthmaticus

Status asthmaticus is a rare, fatal condition, especially in children. Sometimes respiratory support is insufficient with a mechanical ventilator or medical therapy for patients with status asthmaticus. In such situations, early extracorporeal membrane oxygenation application is a useful method for treating refractory respiratory failure. We report on a case of a six-year-old, male child who underwent venovenous extracorporeal membrane oxygenation support for refractory status asthmaticus.

Extracorporeal Life Support: First Year of Experience Implementing the Technique in Slovenia

Extracorporeal life support (ELS) is emerging as a standard treatment option for acute respiratory and/or cardiac failure. In this article we describe our first year of experience with ELS activity in adult medical patients in our center. Veno-venous extracorporeal membrane oxygenation (VV ECMO) support was applied in cases of severe acute respiratory distress syndrome (ARDS) not responsive to conventional treatments. The use of veno-arterial (VA) ECMO support was reserved for cases of cardiac shock refractory to standard treatment and cardiac arrests not responding to conventional resuscitation. A total of 19 patients were treated with ELS during the first year of activity. Eight of these received VV ECMO for ARDS of various etiologies, with a survival rate of 63%. Eleven patients received VA ECMO support due to cardiac failure (2 post-resuscitation). Survival in this group was 45%. We report our results, including complications and organizational issues that we encountered, and describe protocol improvements developed over the short period of time since ELS treatment has been implemented in our center.

Outcomes of Venovenous Extracorporeal Membrane Oxygenation Support for Acute Respiratory Distress Syndrome in Adults

BackgroundDespite improved managements for acute respiratory distress syndrome (ARDS), its mortality remains high. Extracorporeal membrane oxygenation (ECMO) has emerged as the final option for the treatment of ARDS unresponsive to conventional measures. This study describes our experiences of venovenous ECMO support for the treatment of ARDS.Materials and MethodsBetween 2007 and 2010, 56 patients (aged 56.6±13.4 years, 43 males) received venovenous ECMO for the treatment of ARDS. The detailed clinical records were retrospectively reviewed.ResultsBefore the institution of ECMO support, 35 patients (55.4%) required nitric oxide inhalation, 35 patients (55.4%) received continuous renal replacement therapy, and 20 patients (35.7%) were in shock status. The median duration of ECMO support was 164 hours (range, 5 to 1,413 hours). 27 (48%) patients could be successfully weaned from ECMO. Of them, 7 (13%) survived to discharge. On logistic regression analysis, a requirement for higher inspiratory pressure before ECMO support was the only significant factor that could predict ECMO weaning failure.ConclusionThe outcome of venovenous ECMO support for the treatment of ARDS was suboptimal. Further improvements in outcomes should be made through the accumulation of experience and establishment of a standardized protocol for the management of ECMO.

Extracorporeal membrane oxygenation for 2009 influenza A (H1N1) acute respiratory distress syndrome: single-centre experience with 1-year follow-up

During 2009, pandemic influenza A (H1N1) affected France and several patients developed influenza A (H1N1)-associated acute respiratory distress syndrome. The use of extracorporeal membrane oxygenation (ECMO) could be advocated as therapeutic solution. We present our experience with ECMO utilized in patients with influenza A (H1N1)-associated respiratory failure. We conducted a retrospective observational analysis of our experience with veno-venous ECMO for 2009 influenza A (H1N1)-associated respiratory failure. We have excluded from our study all not confirmed cases of influenza A (H1N1). Veno-venous ECMO was always instituted using a percutaneous cannulation technique. Mechanical circulatory support was maintained until respiratory function recovery. Between October 2009 and February 2010, we performed veno-venous ECMO support in 12 patients with influenza A (H1N1)-associated respiratory failure. Mean age was 33 ± 12 years (14-63 years) and there was a prevalence of female sex. Median time from influenza A (H1N1) onset to mechanical ventilation (MV) initiation was 6 days (1-17 days); median time from MV to veno-venous ECMO support was 3 days (1-20 days). Six patients (50%) suffered ventilator-associated pneumonia during ECMO support. Eight patients (66.6%) suffered significant haemorrhage requiring transfusion of more than 2 packed red cells. In two patients (16.6%), there was a thrombosis of the inferior vena cava and one of them experienced pulmonary embolism. Mean duration of ECMO support was 23 ± 14 days (3-47 days); mean duration of mechanical ventilatory support was 24 ± 21 days (6-70 days). ECMO was weaned in 10 patients (83.3%) and all these patients are still alive after a period of follow-up of 13.8 ± 1.12 months (11.03-14.83 months). Two patients (in-hospital mortality of 16.6%) died under ECMO support for refractory septic shock. Veno-venous ECMO for 2009 H1N1-associated respiratory failure gives good results with a very low mortality rate. The use of a mobile unit is a safe procedure and may improve survival of patients who might not be otherwise eligible for transfer to our institution. Larger studies are however required in order to optimize and refine the best treatment strategy in this subgroup of patients.

Improved Survival but Marginal Allograft Function in Patients Treated With Extracorporeal Membrane Oxygenation After Lung Transplantation

Previous reports demonstrate that 1-year survival is severely compromised in patients with severe primary graft dysfunction (PGD) after lung transplantation. We examined if advances in extracorporeal membrane oxygenation (ECMO) support, including polymethylpentene oxygenators and reliance on venovenous (VV) ECMO have improved outcomes in patients with severe PGD after lung transplantation. The analysis included data prospectively collected on all single-lung or double-lung transplants between November 2001 and December 2009. Heart-lung transplants were excluded. Comparisons were made between recipients who did and did not require ECMO for PGD after transplant. Since November 2001, when VV ECMO became the routine treatment for severe PGD after transplant at our center, 28 of 498 patients (6%) have required VV ECMO support. Successful weaning occurred in 27 of 28 (96%). Support was withdrawn for 1 patient with irreversible neurologic injury. Survival was substantially better than in previous reports: 30 days, 82%; 1 year, 64%; and 5 years, 49%. Freedom from bronchiolitis obliterans syndrome was 88% in the ECMO survivors at 3 years, but maximum allograft function was considerably worse than in transplant recipients not requiring ECMO (peak forced expiratory volume in 1 second: 58% in ECMO vs 83% in non-ECMO, p=0.001). Advances in ECMO technology, particularly VV ECMO, have greatly improved the ability to support patients with severe PGD after lung transplantation. VV ECMO is an important tool in the armamentarium of any lung transplant program to optimize patient outcomes; however, strategies to improve lung allograft function in patients experiencing severe PGD are still needed.