Cannulation‐Related Complications on Veno‐Arterial Extracorporeal Membrane Oxygenation: Prevalence and Effect on Mortality

Cannulation‐related complications are a known source of morbidity in patients supported on veno‐arterial extracorporeal membrane oxygenation (VA‐ECMO). Despite its prevalence, little is known regarding the outcomes of patients who suffer such complications. This is a single institution review of cannulation‐related complications and its effect on mortality in patients supported on VA‐ECMO from January 2010–2015 using three cannulation strategies: axillary, femoral, and central. Complications were defined as advanced if they required major interventions (fasciotomy, amputation, site conversion). Patients were divided into two groups (complication present vs. not present) and Kaplan‐Meier analysis was performed to determine any differences in their survival distributions. There were 103 patients supported on VA‐ECMO: 41 (40%), 36 (35%), and 26 (25%) were cannulated via axillary, femoral, and central access, respectively. Cannulation‐related complications occurred in 33 (32%) patients and this did not differ significantly between either axillary (34%), femoral (36%), or central (23%) strategies (P = 0.52). The most common complications encountered were hemorrhage and limb ischemia in 19 (18%) and 11 (11%) patients. Hemorrhagic complications did not differ between groups (P = 0.37), while limb ischemia and hyperperfusion were significantly associated with femoral and axillary cannulation, at a rate of 25% (P < 0.01) and 15% (P = 0.01), respectively. There was no difference in the incidence of advanced complications between cannulation groups: axillary (12%) vs. femoral (14%) vs. central (8%; P = 0.75). In addition, no increase in mortality was noted in patients who developed a cannulation‐related complication by Kaplan‐Meier estimates (P = 0.37). Cannulation‐related complications affect a significant proportion of patients supported on VA‐ECMO but do not differ in incidence between different cannulation strategies and do not affect patient mortality. Improved efforts at preventing these complications need to be developed to avoid the additional morbidity in an already critical patient population.     

Limb ischemia after common femoral artery cannulation for venoarterial extracorporeal membrane oxygenation: an unresolved problem

Purpose

Extracorporeal Life Support Organization Registry data confirm that the number of pediatric patients being supported by extracorporeal membrane oxygenation (ECMO) is increasing. To minimize the potential neurologic effects of carotid artery ligation, the common femoral artery (CFA) is frequently being used for arterial cannulation. The cannula has the potential for obstructing flow to the lower limb, thus increasing ischemia and possible limb loss. We present a single institution's experience with CFA cannulation for venoarterial (VA) ECMO and ask whether any precannulation variables correlate with the development of significant limb ischemia.

Methods

We reviewed all pediatric patients who were supported by VA ECMO via CFA cannulation from January 2000 to February 2010. Limb ischemia was the primary variable. The ischemia group was defined as the patients requiring an intervention because of the development of lower extremity ischemia. The patients in the no-ischemia group did not develop significant ischemia. Continuous variables were reported as medians with interquartile ranges and compared using Mann-Whitney U tests. Differences in categorical variables were assessed using χ² testing (Fisher's Exact). Statistical significance was assumed at P < .05.

Results

Twenty-one patients (age, 2-22 years) were cannulated via the CFA for VA ECMO. Significant ischemia requiring intervention (ischemia group) occurred in 11 (52%) of 21. In comparing the 2 groups (ischemia vs no ischemia), no clinical variables predicted the development of ischemia (Table 1). In the ischemia group, 9 (81%) of 11 had a distal perfusion catheter (DPC) placed. Complications of DPC placement included one case of compartment syndrome requiring a fasciotomy and one patient requiring interval toe amputation. Of the 2 patients in the ischemia group who did not have a DPC placed, 1 required a vascular reconstruction of an injured superficial femoral artery and 1 underwent a below-the-knee amputation. Mortality was lower in the ischemia group (27% vs 60%).

Conclusions

Limb ischemia remains a significant problem, as more than half of our patients developed it. The true incidence may not be known as a 60% mortality in the no-ischemia group could mask subsequent ischemia. Although children are at risk for developing limb ischemia/loss, no variable was predictive of the development of significant limb ischemia in our series. Because of the inability to predict who will develop limb ischemia, early routine placement of a DPC at the time of cannulation may be warranted. However, DPCs do not completely resolve issues around tissue loss and morbidity. Prevention of limb ischemia/loss because of CFA cannulation for VA ECMO continues to be a problem that could benefit from new strategies.     

Arterial protocol including prophylactic distal perfusion catheter decreases limb ischemia complications in patients undergoing extracorporeal membrane oxygenation

Objective

Venoarterial extracorporeal membrane oxygenation (ECMO) is a salvage therapy in patients with severe cardiopulmonary failure. Owing to the large size of the cannulas inserted via the femoral vessels (≤24-F) required for adequate oxygenation, this procedure could result in significant limb ischemic complications (10%-70%). This study evaluates the results of a distal limb perfusion arterial protocol designed to reduce associated complications.

Bridging to a Long‐Term Ventricular Assist Device With Short‐Term Mechanical Circulatory Support

Implanting short‐term mechanical circulatory support (MCS) devices as a bridge‐to‐decision is increasingly popular. However, outcomes have not been well studied in patients who receive short‐term MCS before receiving long‐term left ventricular assist device (LVAD) support. We analyzed outcomes in our single‐center experience with long‐term continuous‐flow (CF)‐LVAD recipients with pre‐implantation short‐term MCS. From November 2003 through March 2016, 526 patients (mean age, 54.7 ± 13.5 years) with chronic heart failure (mean ejection fraction, 21.7 ± 3.6%) underwent implantation of either the HeartMate II (n = 403) or the HeartWare device (n = 123). Before implantation, 269 patients received short‐term MCS with the TandemHeart, the Impella 2.5/5.0, an intra‐aortic balloon pump (IABP), venoarterial extracorporeal membrane oxygenation (VA‐ECMO), or the CentriMag. The short‐term MCS patients were compared with the CF‐LVAD–only patients regarding preoperative demographics, incidence of postoperative complications, and long‐term survival. The 269 patients received the following short‐term MCS devices: 57 TandemHeart, 27 Impella, 172 IABP, 12 VA‐ECMO, and 1 CentriMag. Survival at 30 days, 6 months, 1 year, and 2 years was 94.2, 87.2, 79.4, and 72.4%, respectively, for CF‐LVAD–only patients versus 91.0, 78.1, 73.4, and 65.6%, respectively, for short‐term MCS + CF‐LVAD patients (P = 0.17). Within the short‐term MCS group, survival at 24 months was poorest for patients supported with VA‐ECMO or the TandemHeart (P = 0.03 for both), and survival across all four time points was poorest for patients supported with VA‐ECMO (P = 0.02). Short‐term MCS was not an independent predictor of mortality in multivariate Cox regression models (hazard ratio = 1.12, 95% confidence interval = 0.84–1.49, P = 0.43). In conclusion, we found that using short‐term MCS therapy—except for VA‐ECMO—as a bridge to long‐term CF‐LVAD support was not associated with poorer survival.     

Refractory Pulmonary Edema and Upper Body Hypoxemia During Veno‐Arterial Extracorporeal Membrane Oxygenation—A Case for Atrial Septostomy

Veno‐arterial extracorporeal membrane oxygenation (VA‐ECMO) provides mechanical circulatory support for patients with advanced cardiogenic shock, facilitating myocardial recovery and limiting multi‐organ failure. In patients with severely limited left ventricular ejection, peripheral VA‐ECMO can further increase left ventricular and left atrial pressures (LAP). Failure to decompress the left heart under these circumstances can result in pulmonary edema and upper body hypoxemia, that is, myocardial and cerebral ischemia. Atrial septostomy can decrease LAP in these situations. However, the effects of atrial septostomy on upper body oxygenation remain unknown. After IRB approval, we identified 9 out of 242 adult VA‐ECMO patients between January 2011 and June 2016 who also underwent atrial septostomy for refractory pulmonary edema/upper body hypoxemia. We analyzed LAP/pulmonary capillary wedge pressure (PCWP), right atrial pressures (RAPs), P_aO₂/F_iO₂ ratios (blood samples from right radial artery), intrathoracic volume status, and resolution of pulmonary edema before and up to 48 h after septostomy. There were no procedure‐related complications. Thirty‐day survival was 44%. LAP/PCWP decreased by approximately 40% immediately following septostomy and remained so for at least 24 h. P_aO₂/F_iO₂ ratios significantly increased from 0.49 (0.38–2.12) before to 5.35 (3.01–7.69) immediately after septostomy and continued so for 24 h, 6.6 (4.49–10.93). Radiographic measurements also indicated a significant improvement in thoracic intravascular volume status after atrial septostomy. Atrial septostomy reduces LAP and improves upper body oxygenation and intrathoracic vascular volume status in patients developing severe refractory pulmonary edema while undergoing peripheral VA‐ECMO. Atrial septostomy therefore appears safe and suitable to reduce the risk of upper body ischemia under these circumstances.     

Managing Traps and Pitfalls During Initial Steps of an ECMO Retrieval Program Using a Miniaturized Portable System: What Have We Learned From the First Two Years?

The aim of this study was to provide early and mid‐term results of the newly established extracorporeal membrane oxygenation (ECMO) retrieval service in a tertiary cardiothoracic center using the miniaturized portable Cardiohelp System (Maquet, Rastatt, Germany). A particular attention was paid to organizational and logistic specifics as well as challenges and pitfalls associated with initial phase of the program. From January 2015 until January 2017 a heterogenic group of 28 consecutive patients underwent ECMO implantation in distant hospitals for acute cardiac, pulmonary or combined failure as a bridge‐to‐decision and were subsequently transported to our institution. Each cannulation was performed bedside on intensive care units (ICU) using the Seldinger's technique. Early outcomes and mid‐term overall survival with up to two‐year follow‐up along with the impact of ongoing cardiopulmonary resuscitation (CPR) on outcome were presented. Also, changes in hemodynamics and tissue perfusion factors 24 h after ECMO implantation were evaluated. ECMO implantations were performed in 15 distant departments with the median distance of 23(10;40) (maximum 60) km. A total of 15 patients (54%) were cannulated under CPR with the median duration of 30(20;110) (maximum 180) min. After 24 h of support there were significant improvements in SvO₂ (P = 0.021), mean arterial pressure (P = 0.027), FiO₂ (P = 0.001), lactate (P = 0.001), and pH (P < 0.001). The mean ECMO support duration was 96 ± 100 (maximum 384) hours, whereas 11 patients (40%) were weaned off support and discharged from hospital. Overall cumulative survival in patients without the need for CPR was 61.5% at one week and 38.5% at 1 month, 6 month, and 1 year, whereas patients requiring CPR survived in 40% at one week, and 33.3% at 1 month, 6 month, and 1 year (Log‐Rank (Mantel‐Cox) P = 0.374, Breslow (Generalized Wilcoxon) P = 0.162). Our initial experience shows that launching new ECMO retrieval programs in centers with sufficient ICU capacities and local ECMO experience can be feasible and associated with acceptable “real world” results despite the initial learning curve. Rapid logistical organization and team flexibility are the key points to ensure comparable survival of patients requiring prolonged CPR.     

Incidence,Risk Factors,and Outcomes of Hyperbilirubinemia in Adult Cardiac Patients Supported by Veno‐Arterial ECMO

The aims of this study were to evaluate the incidence, risk factors, and outcomes of hyperbilirubinemia in cardiac patients with veno‐arterial (VA) ECMO. Data on 89 adult patients with cardiac diseases who received VA ECMO implantation in our hospital were retrospectively reviewed. All patients were divided into the following three groups: 24 in normal group (N, total bilirubin [TBIL] ≤3 mg/dL), 30 in high bilirubin group (HB, 6 mg/dL ≥ TBIL > 3 mg/dL), and 35 in severe high bilirubin group (SHB, TBIL > 6 mg/dL). lg(variables + 1) was performed for nonnormally distributed variables. The incidence of hyperbilirubinemia (>3 mg/dL) was 73%. In a multiple linear regression analysis, lg(peak TBIL + 1) was significantly associated with lg(peak AST + 1) (b‐coefficient 0.188, P = 0.001), lg(peak pFHb + 1) (b‐coefficient 0.201, P = 0.003), and basic TBIL (b‐coefficient 0.006, P = 0.009). Repeated measurement analysis of variance revealed that the main effect for three groups in pFHb and lg(AST + 1) was significant at first 3 days during ECMO. The patients in SHB had low platelets during ECMO and low in‐hospital survival rate. Hyperbilirubinemia remains common in patients with VA ECMO and is associated with low platelets and high in‐hospital mortality. Hemolysis and liver dysfunction during ECMO and basic high bilirubin levels are risk factors of hyperbilirubinemia.     

Effect of Anemia on Prognosis in Patients on Extracorporeal Membrane Oxygenation

Anemia is a component of the pathological triangle in cardiorenal anemia syndrome and is a risk factor for mortality in acute respiratory distress syndrome. This study assessed the predictive value of anemia for outcomes in critically ill patients receiving extracorporeal membrane oxygenation (ECMO) support. This retrospective study analyzed patients who received ECMO support at the cardiovascular surgery intensive care unit in the study institute between July 2003 and March 2012. Patient data, such as demographic information, etiologies of ECMO implementation, clinical parameters, and in‐hospital and 6‐month mortality rates, were statistically analyzed. The overall in‐hospital mortality rate among the enrolled 295 patients was 55.6%. Multivariate logistical regression analysis indicated that age, albumin levels, sequential organ failure assessment (SOFA) score, and hemoglobin (Hb) level on ECMO day 1 exhibited independent prognostic significance for predicting in‐hospital mortality rate. The SOFA score exhibited the highest areas under the receiver operating characteristic curve value (0.812 ± 0.025). The Hb level on ECMO day 1 exhibited satisfactory calibration and discriminatory power. The cumulative 6‐month survival rates differed significantly between patients with Hb levels less than and more than 8.85 g/dL (30.6 vs. 54.0%, respectively, P < 0.001). This study indicated that old age, low albumin levels, low Hb levels, and higher SOFA scores on ECMO day 1 increased the risk of mortality. The Hb level is a readily measurable parameter and with good predictive power for critical patients on ECMO.     

Extracorporeal Membrane Oxygenation Support in Trauma Versus Nontrauma Patients with Noninfectious Acute Respiratory Failure

The utility of extracorporeal membrane oxygenation (ECMO) in patients with acute respiratory distress syndrome (ARDS) of noninfectious origin remains unclear. Data on patients with ARDS of noninfectious origin who underwent ECMO were reviewed retrospectively. We compared the pre‐ECMO characteristics and hospital outcomes of patients with traumatic and nontraumatic ARDS. In total, 23 patients (trauma, n = 9; nontrauma, n = 14) were included in the study. The mean patient age was 42 years, there were three females, and the mean pre‐ECMO Simplified Acute Physiologic Score (SAPS) II was 60.0 (49.0–71.0). The hemoglobin level was lower and the prothrombin time (PT) more prolonged, prior to initiation of ECMO, in traumatic compared with nontraumatic ARDS patients. During the first 48 h of ECMO support, the coagulation parameters did not differ between the two groups, but the platelet counts, PT, and activated partial thromboplastin time indicated that coagulopathy was developing in all patients. The hospital and 28‐day mortality rates were 21.7 and 13.0%, respectively, and serious neurological outcomes (cerebral performance category [CPC] of three points or more) developed in 26.1% of all patients; however, the extent of such outcomes did not differ between traumatic and nontraumatic ARDS patients. Upon multivariate analysis, the pre‐ECMO SAPS II tended to be associated with composite events (i.e., hospital death and/or a CPC of three points or more) (P = 0.051). Additionally, a history of hypertension and an elevated pre‐ECMO SAPS II were significant risk factors for serious neurological outcomes among hospital survivors (n = 18). In conclusion, ECMO support can be associated with favorable outcomes in patients with ARDS of noninfectious origin, irrespective of whether the ARDS is associated with trauma. The pre‐ECMO SAPS II and a history of hypertension may be independent risk factors for poor outcomes.     

Extracorporeal Membrane Oxygenation for Refractory Severe Respiratory Failure in Acute Interstitial Pneumonia

Acute interstitial pneumonia (AIP) is a rare idiopathic interstitial lung disease with rapid progressive respiratory failure and high mortality. In the present report, three cases of AIP complicated by refractory respiratory failure supported with extracorporeal membrane oxygenation (ECMO) are presented. One male and two female patients (ages 27–59) were included. Venovenous ECMO support was provided using miniaturized systems, with two‐site femoro‐jugular circuit configuration. Despite lung protective ventilation, prone position and neuromuscular blockade, refractory respiratory failure of unknown etiology supervened (ratio of arterial oxygen partial pressure to fractional inspired oxygen 46–130) and ECMO was initiated after 3–7 days of mechanical ventilation. AIP diagnosis was established after exclusion of infectious and noninfectious acute respiratory distress syndrome on the basis of clinical and analytical data, bronchoalveolar lavage analysis and lung imaging, with a confirmatory surgical lung biopsy revealing diffuse alveolar damage of unknown etiology. Immunosuppressive treatment consisted in high‐dose corticosteroids and cyclophosphamide in one case. Two patients survived to hospital discharge. ECMO allowed AIP diagnosis and treatment in the presence of refractory respiratory failure, therefore reducing ventilator‐induced lung injury and bridging lung recovery in two patients. ECMO referral should be considered in refractory respiratory failure if AIP is suspected.     

Distal Limb Perfusion: Achilles' Heel in Peripheral Venoarterial Extracorporeal Membrane Oxygenation

Extracorporeal membrane oxygenation (ECMO) is a temporary mechanical circulatory assist method that offers circulatory as well as respiratory support efficiently via peripheral access; however, it is liable to complications. Limb ischemia is one of the notorious complications of ECMO but can be avoided utilizing a proper distal limb perfusion method. A retrospective study of patients undergoing peripheral venoarterial (VA) ECMO for various reasons between June 2010 and December 2012 was performed. All patients were evaluated by our multidisciplinary team for suitability as candidates for ECMO. A peripheral VA‐ECMO circuit was implanted via groin: inflow cannula in the femoral vein, an outflow cannula and distal‐perfusion cannula, or an introducer sheath in the femoral artery. During the study period, 83 patients underwent various types of ECMO; 45 received peripheral VA‐ECMO. Distal limb perfusion was achieved with an introducer sheath (6–8 Fr) in 13 cases and with a distal‐perfusion cannula (10–12 Fr) in 32 cases. Nine (20%) patients developed signs of ischemia; five (11.2%) were treated conservatively, while four (8.8%) required surgical intervention. One patient required a below‐knee amputation. The incidences of limb ischemia and limb ischemia requiring surgical intervention were significantly higher for the introducer sheath compared with the cannula (30.6 vs. 15.6% and 15.4 vs. 6.25%, respectively). Moreover, the patients supported on ECMO with a distal‐perfusion cannula spent a significantly longer time on ECMO compared with the ones in whom an introducer sheath was used (11.9 ± 9.1 vs. 7.7 ± 4.3 days). The mean cannula size was significantly greater than the mean introducer sheath size (11.1 ± 1.3 vs. 7.0 ± 1.1 Fr). Use of a distal‐perfusion cannula is a most reliable method of limb perfusion in peripheral VA‐ECMO. The cannula can ensure adequate and smooth perfusion of the limb owing to its large caliber, its less turbulent flow, the ability it provides to monitor the flow, and the option to attach a side port.     

Cerebral and lower limb near-infrared spectroscopy in adults on extracorporeal membrane oxygenation

Percutaneous femoral venoarterial (VA) or jugular venovenous (VV) extracorporeal membrane oxygenation (ECMO) can result in delivery of hypoxic blood to the brain, coronaries, and upper extremities. Additionally, VA-ECMO by percutaneous femoral artery cannulation may compromise perfusion to the lower limbs. Use of near-infrared spectroscopy (NIRS) detects regional ischemia and warns of impending hypoxic damage. We report the first known series with standardized monitoring of this parameter in adults on ECMO. This is an institutional review board-approved single institution retrospective review of patients with NIRS monitoring on ECMO from July 2010 until June 2011. Patients were analyzed for drops in NIRS tracings below 40 or >25% from baseline. VA-ECMO and VV-ECMO were initiated by percutaneous cannulation of the femoral vessels and the internal jugular vein, respectively. Sensors were placed on the patients' foreheads and on the lower limbs. NIRS tracings were recorded, analyzed, and correlated with clinical events. Twenty patients were analyzed (median age: 47.5 years): 17 patients were placed on VA-ECMO, and three patients on VV-ECMO. The median duration on ECMO was 7 days (range 2-26). One hundred percent of patients had a significant drop in bilateral cerebral oximetry tracings resulting in hemodynamic interventions, which involved increasing pressure, oxygenation, and/or ECMO flow. In 16 patients (80%), these interventions corrected the underlying ischemia. Four patients (20%) required further diagnostic intervention for persistent decreased bilateral and/or unilateral cerebral oximetry tracings, and were found to have a cerebrovascular accident (CVA). Six (30%) patients had persistent unilateral lower limb oximetry events, which resolved upon placement or replacement of a distal perfusion cannula. No patient was found to have either lower limb ischemia or a CVA with normal NIRS tracings. Use of NIRS with ECMO is important in detecting ischemic cerebral and peripheral vascular events. This allows for potential correction of the underlying process, thus preventing permanent ischemic damage.     

Extracorporeal Membrane Oxygenation Outcomes After the Comprehensive Stage II Procedure in Patients With Single Ventricles

Outcomes for extracorporeal membrane oxygenation (ECMO) have been described for patients with single ventricle physiology (SVP) undergoing cavopulmonary connection (Glenn procedure). An alternative surgical pathway for patients with SVP consists of an initial hybrid procedure followed by a comprehensive Stage II procedure. No data exist describing the outcomes of patients requiring ECMO after the comprehensive Stage II procedure. The goal of this study is to describe the outcomes for patients who required ECMO after the comprehensive Stage II procedure. Data from the Extracorporeal Life Support Organization (ELSO) registry from 2001 to 2015 for children undergoing the comprehensive Stage II procedure older than 3 months of age were retrospectively analyzed. Demographics and ECMO characteristics were recorded. A total of six children required ECMO support after the comprehensive Stage II procedure (2 males, 4 females). Four patients had the diagnosis of hypoplastic left heart syndrome and two patients had the diagnosis of an unbalanced atrioventricular septal defect. Bypass time was 242.8 ± 110.9 min and cross‐clamp time was 91.2 ± 46.2 min for the surgical procedure. Weight was 5.8 ± 1.3 kg and age was 150.2 + 37.9 days at time of ECMO. ECMO duration was 276.0 ± 218.1 h. Complications during the ECMO run included hemorrhage in four patients (67%), renal dysfunction in two patients (33%), and neurologic injury in two patients (33%). Four patients (67%) were discharged alive after ECMO decannulation. Despite being a much more extensive surgical procedure, the morbidity and mortality after ECMO in patients undergoing the comprehensive Stage II procedure are similar to those in patients undergoing the Glenn procedure. If needed, ECMO support is reasonable for patients after the comprehensive Stage II procedure.     

Use of ECMO support in pediatric patients with severe thoracic trauma

BackgroundExtracorporeal membrane oxygenation (ECMO) has been used in the non-trauma setting for over 30 years. However, the use of ECMO in trauma remains a difficult question, as the risk of bleeding must be weighed against the benefits of cardiopulmonary support.MethodsRetrospective review of children who sustained severe thoracic trauma (chest abbreviated injury score ≥ 3) and required ECMO support between 2009 and 2016.ResultsOf the 425 children who experienced severe thoracic trauma, 6 (1.4%) underwent ECMO support: 67% male, median age 4.8 years, median ISS 36, median GCS 3, and overall survival 83%. The median hospital day of ECMO initiation was 2 with a median ECMO duration of 7 days. All cannulations occurred through the right neck regardless of the size of the child. Five initially had veno-venous support with 1 requiring conversion to veno-arterial (VA) support. Both children on VA support suffered devastating cerebrovascular accidents, one of which ultimately led to withdrawal of care and death. Complications in the cohort included: paraplegia (1), neurocognitive defects/dysphonia (1), infected neck hematoma (1), deep femoral venous thrombosis (1), bilateral lower extremity spasticity (1).ConclusionThis small cohort supports the use of ECMO in children with severe thoracic injuries as a potentially lifesaving intervention, however, not without significant complication.Level of EvidenceIV.     

Extracorporeal membrane oxygenation cannulation trends for pediatric respiratory failure and central nervous system injury

BackgroundGuidelines regarding arterial cannula site and cannula site-specific risks of central nervous system (CNS) injury for pediatric patients requiring extracorporeal membrane oxygenation (ECMO) support are lacking. We reviewed cannulation trends for pediatric respiratory failure and evaluated CNS complication rates by cannulation site and mode of support.MethodsThe Extracorporeal Life Support Organization (ELSO) registry was queried for all pediatric respiratory failure patients <18 years treated from 1993-2007. The primary outcome was radiographic evidence of CNS injury.ResultsVenoarterial (VA) support was used in 62% of 2617 ECMO runs. The carotid artery was used in 93% of VA patients. Femoral artery use increased in patients >5 years of age and >20 kg. Venovenous (VV) ECMO was used in >50% of children >10 years. No significant difference was identified in CNS injury between carotid and femoral cannulation in any age group but the femoral group was small (4.4%). VA support was independently associated with increased odds of CNS injury compared to VV cannulation (OR, 1.6).ConclusionVA ECMO is the most common mode of support in pediatric respiratory failure patients. Although no significant difference in CNS injury was noted between carotid and femoral artery cannulation, the odds of injury were significantly higher than VV support.     

Evaluation of Hemodynamic Performance of a Combined ECLS and CRRT Circuit in Seven Positions With a Simulated Neonatal Patient

As it is common for patients treated with extracorporeal life support (ECLS) to subsequently require continuous renal replacement therapy (CRRT), and neonatal patients encounter limitations due to lack of access points, inclusion of CRRT in the ECLS circuit could provide advanced treatment for this population. The objective of this study was to evaluate an alternative neonatal ECLS circuit containing either a Maquet RotaFlow centrifugal pump or Maquet HL20 roller pump with one of seven configurations of CRRT using the Prismaflex 2000 System. All ECLS circuit setups included a Quadrox‐iD Pediatric diffusion membrane oxygenator, a Better Bladder, an 8‐Fr arterial cannula, a 10‐Fr venous cannula, and 6 feet of ¼‐inch diameter arterial and venous tubing. The circuit was primed with lactated Ringer's solution and packed human red blood cells resulting in a total priming volume of 700 mL for both the circuit and the 3‐kg pseudopatient. Hemodynamic data were recorded for ECLS flow rates of 200, 400, and 600 mL/min and a CRRT flow rate of 50 mL/min. When a centrifugal pump is used, the hemodynamic performance of any combined ECLS and CRRT circuit was not significantly different than that of the circuit without CRRT, thus any configuration could potentially be used. However, introduction of CRRT to a circuit containing a roller pump does affect performance properties for some CRRT positions. The circuits with CRRT positions B and G demonstrated decreased total hemodynamic energy (THE) levels at the post‐arterial cannula site, while positions D and E demonstrated increased post‐arterial cannula THE levels compared to the circuit without CRRT. CRRT positions A, C, and F did not have significant changes with respect to pre‐arterial cannula flow and THE levels, compared to the circuit without CRRT. Considering hemodynamic performance, for neonatal combined extracorporeal membrane oxygenation (ECMO) and CRRT circuits with both blood pumps, we recommend the use of CRRT position A due to its hemodynamic similarities to the ECMO circuit without CRRT.     

Post-cardiotomy extracorporeal cardiopulmonary resuscitation in neonates with complex single ventricle: analysis of outcomes

Objective: Extracorporeal cardiopulmonary resuscitation (ECPR) in children with cardiac arrest refractory to conventional cardiopulmonary resuscitation (CPR) has been reported with encouraging results. We sought to review outcomes of neonates with functional single ventricle (FSV) receiving post-cardiotomy ECPR. Methods: Forty-eight patients who required post-cardiotomy extracorporeal membrane oxygenation (ECMO) since the introduction of our ECPR protocol (January2007–December 2009) were identified. Twenty-seven were neonates. Review of records and survival analysis were conducted. Results: Of 27 neonates receiving post-cardiotomy ECMO 20 had FSV. Fourteen had ECPR. Ten underwent Norwood operation (NO) for hypoplastic left heart syndrome (HLHS). Four had FSV other than HLHS. Three underwent Damus–Kay–Stansel or modified NO with systemic-to-pulmonary shunt (SPS) and one SPS with anomalous pulmonary venous connection repair. Mean age and weight were 7.8 ± 2.9 days and 3.44 ± 1.78 kg, respectively. ECMO median duration was 6 days (interquartile range (IQR) 3–14). Survival to ECMO discontinuation was 79% (11 of 14 patients) and at hospital discharge was 57% (8 of 14 patients). The most common cause of death was multi-organ failure (four of six deaths). At last follow-up (median: 11 months (1–34)) 43% of patients were alive. CPR mean duration for patients with favorable versus unfavorable outcome was 38.6 ± 6.3 versus 42.1 ± 7.7 min (p = 0.12). Previously reported determinants for poorer prognosis in conventional non-rescue ECMO (such as pre-ECMO pH < 7.2, renal, neurological or pulmonary hemorrhage complications, and pre- and post-vasoactive inotropic score) did not influence outcome between survivors and non-survivors (p > 0.05). Conclusions: ECMO support in neonates with FSV requiring ECPR can result in favorable outcome in more than half of patients at hospital discharge. Aggressive strategy toward timely application of ECPR is justified. Expeditious ECPR deployment after proper patients’ selection, refinement of CPR quality and use of adjunctive neuroprotective interventions, such as induced hypothermia, might further improve outcomes.     

体外膜氧合治疗期间缺血性肝炎发病率、危险因素及预后

目的 研究探讨体外膜氧合（extracorporeal membrane oxygenation, ECMO）治疗期间缺血性肝炎（ischemic hepatitis, IH）的发生率、危险因素及结局。 方法 回顾性收集了82例因心源性疾病接受静脉-动脉（venous-arterial, VA）ECMO支持的成年患者（≥18周岁）资料,排除有肝、肾疾病病史者。患者分为IH组和非缺血性肝炎（NIH）组,对患者临床资料进行分析比较。 结果 20例（24.4%）患者发生IH,且均出现在使用ECMO 24 h内。AST随着时间的延长逐渐下降,而总胆红素（total bilirubin, TBIL）却逐步增高。IH组的生存率显著低于NIH组（15% 比 50%,P=0.006）。此外,IH组急性肾功能衰竭的发病率显著高于NIH组（70.0% 比 41.9%, P=0.029）。多元回归模型发现,内科心功能衰竭［比值比（odds ratio, OR） =149.71,95%CI 6.22～3 602.58,P=0.002］、乳酸最大值（OR=1.41,95%CI 1.14～1.76,P=0.002）、TBIL最大值（OR=1.02,95%CI 1.01～1.04,P=0.010）是ECMO支持24 h内发生IH的危险因素。 结论 IH在ECMO中较为常见,而且发生IH的患者预后较差。内科心功能衰竭、乳酸和TBIL最大值是VA ECMO支持期间IH的危险因素。     

Venovenous perfusion in ECMO for newborn respiratory insufficiency. A clinical comparison with venoarterial perfusion.

Venoarterial (VA) extracorporeal membrane oxygenation (ECMO) has been successful in the treatment of newborns less than 1 week of age and greater than 2000 gm birthweight with respiratory failure resistant to current medical and surgical management. While VA ECMO supports the heart as well as the lungs, it has the disadvantage of requiring carotid artery ligation and the possibility of perfusing air bubbles or particles into the arterial tree. We have treated 11 newborns with respiratory failure with venovenous (VV) ECMO returning the oxygenated blood to a cannula in the distal iliac vein. We compared these patients with 16 patients treated during the same period of time with VA ECMO. Three of the 11 VV patients required conversion to VA ECMO because of inadequate oxygenation and unstable hemodynamic situations. Ten of the 11 VV patients survived. Eleven of the 16 VA patients survived. The better survival in these patients treated with VV ECMO is attributed to their more favorable initial condition compared to patients treated with VA ECMO. The disadvantages of VV ECMO include a longer operative time to place the cannulas, groin wound problems, and persistent leg swelling along with the necessity to convert some patients to VA ECMO. Although this experience demonstrates that newborns with severe respiratory failure can be supported with VV ECMO, the complications and lack of practical advantages over VA lead us to recommend VA ECMO for routine clinical use at present.     

Venovenous extracorporeal membrane oxygenation in neonates with respiratory failure

Venoarterial (VA) extracorporeal membrane oxygenation (ECMO) has been successful in support of neonates with respiratory failure but requires right common carotid artery ligation. While no short-term neurologic complications have resulted from neonatal carotid ligation, late complications may occur. For both VA ECMO and venovenous (VV) ECMO, blood is drained from the right atrium via a right internal jugular cannula, oxygenated by a membrane lung, and returned to the patient. VV ECMO spares the carotid by perfusing the oxygenated blood into a vein. VV ECMO gave total respiratory support to three neonates with respiratory failure and each infant survived. In comparison with three similar VA ECMO patients, the VV patients required higher ECMO circuit flow rates and had lower systemic arterial Po2s. Length of time on ECMO, length of hospital stay, and neurologic outcome were similar in the VV and VA patients. Differences among the patients were related to their primary disease rather than to the mode of ECMO support. The VV patients had cannulation of the femoral vein for perfusion of oxygenated blood. Late complications may occur from femoral vein ligation as well as from carotid ligation so long-term follow-up is needed to assess these two ECMO techniques.