Outcomes and factors associated with early mortality in pediatric postcardiotomy veno‐arterial extracorporeal membrane oxygenation

Mortality and morbidity of children received veno‐arterial extracorporeal membrane oxygenation (VA‐ECMO) support after cardiac surgery remain high despite remarkable advances in medical management and devices. The purpose of this study was to describe outcomes and risk factors of applying VA‐ECMO in the surgical pediatric population. We retrospectively analyzed 85 consecutive pediatric patients (aged <18 years) who received postcardiotomy VA‐ECMO from January 2010 to December 2018. Median (IQR) age at ECMO implantation in this cohort was 12.7 (6.4, 43.2) months, median weight was 8.5 (6.0, 12.8) kg, mean ECMO duration was 143.2 ± 81.6 hours and mean hospital length of stay was 48.4 ± 32.4 days. Seventy‐five patients (88.2%) were indicated for postcardiotomy cardiogenic shock. The successful ECMO weaning rate was 70.6% and in‐hospital mortality was 52.9%. The most common diagnosis was transposition of great arteries (n = 18, 21.2%), while acute kidney injury occurred most often (n = 64, 75.3%). Multivariate logistic regression analysis showed that thrombocytopenia, hemolysis, and nosocomial infection were positively correlated with in‐hospital mortality. Multivariate Cox proportional hazard regression analysis presented that thrombocytopenia significantly increased the 180‐day mortality in patients with successful weaning. Therefore, multiple factors had adverse effects on prognosis. Patient selection and procedures from ECMO implantation to weaning need to be closely monitored and performed in a timely manner to improve outcome.     

Patient with liver dysfunction while maintained on veno‐venous extracorporeal membrane oxygenation should not be overlooked as a potential donor

This report describes transplantation of liver allograft from a circulatory death donor who was supported by veno‐venous extracorporeal membrane oxygenation (ECMO) for 14 days and presented with severely altered liver functions. Successful liver transplant was done in a patient with hepatocellular carcinoma (HCC) in the background of primary sclerosing cholangitis. There was immediate graft function and uneventful recovery with stable graft function at 1‐year follow‐up. This case illustrates the ability of veno‐venous ECMO to resuscitate organs in the presence of severe dysfunction, and perhaps, lessons from this case may be incorporated to optimize the condition of organs rescued from these marginal donors and exemplify the use of ECMO in normothermic regional perfusion in donors after circulatory death.     

Venovenous versus venoarterial extracorporeal membrane oxygenation in congenital diaphragmatic hernia

Background: Extracorporeal membrane oxygenation (ECMO) has a significant role as a final rescue modality in severe respiratory failure of the newborn with congenital diaphragmatic hernia (CDH). The objective of this study was to compare the efficiency of venovenous (VV) versus venoarterial (VA) ECMO in newborns with CDH.Methods: A retrospective report of 11 years experience (1990 through 2001) of a single center, comparing VV and VA ECMO is given. VV ECMO was the preferred rescue modality for respiratory failure unresponsive to maximal medical therapy. Only when the placement of a VV ECMO 14F catheter was not possible, VA ECMO was used. Forty-six patients met ECMO criteria; 26 were treated with VV ECMO and 19 with VA ECMO. One patient underwent conversion from VV to VA ECMO.Results: Before ECMO, there was no difference between VV and VA ECMO patients in mean oxygenation index (83 v 83), mean airway pressure (18.4 v 18.9 cm H₂O), ECMO cannulation age (28 v 20 hours), or in the percentage of patients who needed dopamine and dobutamine (100% v 100%). From November 1994, nitric oxide (NO) was available; before ECMO, 11 of 14 (79%) VV ECMO patients received NO versus 9 of 10 (90%) patients in the VA group. VV ECMO patients were larger (3.34 v 2.77 kg; P < .05) and of advanced gestational age (39.0 v 36.9 wk; P < .05) compared with VA ECMO patients. There was no significant difference between VV and VA ECMO patients in survival rate (18 of 26, 69% v 13 of 19, 68%), ECMO duration (152 v 150 hours), time of extubation (32.0 v 33.5 days), age at discharge (73 v 81 days), or incidence of short-term intracranial complications (3.8% v 10.5%) or myocardial stun (3.8% v 15.8%).Conclusions: The authors conclude that VV ECMO is as reliable as VA ECMO in newborns with CDH in severe respiratory failure who need ECMO support and who can accommodate the VV double-lumen catheter. Because of its potential advantages, VV ECMO may be the preferred ECMO method in these infants.     

A description of a prototype miniature extracorporeal membrane oxygenation circuit using current technologies in a sheep model

In the United States, standardization of neonatal extracorporeal membrane oxygenation (ECMO) circuit was achieved during the 1980s. Since that time, the consoles and components of the ECMO circuit have remained fundamentally unchanged (bladder, rollerpump, silicone membrane oxygenator). Extracorporeal technology, however, has witnessed many significant advancements in components during the past two decades. These new technologies have characteristics that may improve outcomes when applied in the ECMO arena. Understanding how these technologies perform in long-term applications is necessary. Therefore, the purpose of this project is to evaluate the performance of a miniature ECMO circuit consisting of current generation technologies in an animal model. An ECMO circuit (prime volume 145 mL) was designed that included a hollow fiber oxygenator and a remote mounted centrifugal pump. All circuit tubing and components were surface coated. Three sheep (approx 13 kg) were placed on ECMO using standard neck cannulation techniques and maintained according to clinical protocols. Technical implementation, oxygenator function, and hematological parameters were accessed. Duration of ECMO was 20, 48, and 58 hours. There was no evidence of oxygenator failure, as measured by pressure drop and oxygen transfer, in any of the procedures. No plasma leak was observed in any oxygenators. Platelet count trended downward after 24 hours. Visual inspection after ECMO showed very little evidence of gross thrombosis. This ECMO circuit design departs dramatically from the typical North American systems. The use of this console and components facilitated a 70% reduction in priming volume over a traditional ECMO circuit. Further investigations should be conducted to determine if circuit miniaturization can reduce the morbidity associated with blood product consumption and the bloods contact with the artificial surfaces of the ECMO circuitry.     

Acceptance and transfer to a regional severe respiratory failure and veno‐venous extracorporeal membrane oxygenation (ECMO) service: predictors and outcomes

The use of extracorporeal membrane oxygenation for respiratory failure is high risk and resource intensive. In England, five centres provide this service and patients who are referred have four possible outcomes: declined transfer due to perceived futility; accepted in principle but remain at the referring centre with ongoing surveillance; retrieved using conventional ventilation; or retrieved on extracorporeal support. The decision‐making process leading to these outcomes has not previously been examined. We evaluated referrals to one centre and identified factors associated with each decision outcome. Five hundred and sixty‐four patients were analysed from January 2012 to October 2015. One hundred and fifty‐seven patients were declined; multivariate analysis demonstrated associated factors to be: age (odds ratio (95% confidence interval) 1.05 (1.04–1.07)); immunocompromise (4.95 (2.58–9.67)); lactate (1.11 (1.01–1.22)); duration of ventilation (1.08 (1.04–1.14)); and cardiac failure (3.22 (1.04–10.51)). Factors associated with the decision to retrieve an accepted patient were: plateau pressure (1.05 (1.01–1.10)); ratio of arterial oxygen partial pressure to fractional inspired oxygen (0.89 (0.85–0.93)); partial pressure of carbon dioxide in arterial blood (1.13 (1.03–1.25)); and the absence of non‐pulmonary infection (0.31 (0.15–0.61)). Only pH was independently associated with the decision to transfer on extracorporeal support (0.020 (0.002–0.017)). Six‐month survival in the declined, non‐retrieved, conventionally retrieved and extracorporeal‐retrieved groups was 16.6%, 71.1%, 76.7% and 72.1%, respectively, substantially supporting the decision‐making model. Survival in the accepted group exceeds that reported previously. However, a proportion of those declined do survive and some remotely managed patients die. This suggests the approach does not account for some important survival‐determining factors.     

Outcomes in patients requiring repeat extracorporeal membrane oxygenation

Background

As the number of patients requiring extracorporeal membrane oxygenation (ECMO) increases nationwide, many patients may require ECMO more than once. We review our experience and outcomes in patients requiring repeat ECMO support.

Methods

The Nebraska ECMO Research Database was utilized for data analysis, and repeat ECMO patients (REPs) were compared to the overall ECMO population.

Results

Of 246 patients, 2.4% (6/246) were REPs. There was no statistical difference between the median days of initial support run (P = 0.670) and second support run (P = 0.813) for REPs when comparing to the non‐REP population. Median hospital length of stay for REPs was 53 days (16‐124) compared to the non‐REPs, who had a median hospital length of stay of 22 days (1‐270); P = 0.043. In‐hospital mortality rate for REPs was 50% (3/6) and 50% for non‐REPs (120/240). Survival 30 days postdischarge for REPs was 50% (3/6) compared to non‐REPs at 48.3% (116/240); P = NS.

Conclusions

Outcomes for repeat ECMO patients compare favorably to the overall ECMO population and suggest a need to explore and broaden the clinical indications for repeat ECMO.     

Management of a young patient with dextrocardia,atrial septal defect,and Eisenmenger syndrome with venous‐venous extracorporeal membrane oxygenation and heart‐lung transplantation

Dextrocardia is a rare congenital condition which presents important challenges for surgical management. We discuss a patient with dextrocardia, atrial septal defect, and Eisenmenger syndrome, which ultimately led to decompensated end‐stage lung disease and heart‐lung transplant. Venous‐venous extracorporeal membrane oxygenation was an important strategy to bridge the patient until donor organs became available. Transplantation of a heart‐lung block allowed for the treatment of the patient's underlying congenital heart defect, anatomic reversal of dextrocardia with appropriate venous and arterial connections, and management of pulmonary damage from pulmonary hypertension.     

Nesiritide during extracorporeal membrane oxygenation

Nesiritide is a recombinant formulation of B-type natriuretic peptide (BNP). Preliminary experience in the adult population has shown nesiritide to be an effective agent in the treatment of decompensated congestive heart failure (CHF) in adults. Given its physiological effects, it may be an effective agent in other clinical scenarios. We report the use of nesiritide in two infants during extracorporeal membrane oxygenation (ECMO). In one patient, nesiritide in doses up to 0.09 microg.kg(-1).min(-1) were used to control mean arterial pressure while in the other patient, doses of 0.01-0.03 microg.kg(-1).min(-1) were used to augment urine output. The potential applications of nesiritide and dosing regimens for this agent in the ECMO population are discussed.     

Use of the CDI blood parameter monitoring system 500 for continuous blood gas measurement during extracorporeal membrane oxygenation simulation

The Oximetrix III Opticath (Abbott Critical Care Systems) is used for continuous measurement of venous saturation in a variety of applications, including extracorporeal membrane oxygenation (ECMO), despite clinical reports that have presented data showing poor accuracy of these devices. The CDI Blood Parameter Monitoring System 500 (Terumo) is an inline blood gas monitoring tool commonly used during cardiopulmonary bypass procedures to continuously assess oxygen saturation, blood gases, potassium, and bicarbonate. The purpose of this experiment was to compare the Opticath and the CDI 500 in trending venous blood saturation during a simulation of ECMO. An ECMO simulation circuit consisting of a silicone rubber membrane oxygenator and a stainless steel heat exchanger was constructed, and a standard venous reservoir bag was used to represent the patient. The CDI and the Opticath were incorporated side by side into a shunt that originated just before the oxygenator and returned flow to the venous line. The circuit was primed with fresh porcine blood and conditioned with the addition of CO2 to simulate typical venous blood under ECMO conditions. After an initial calibration procedure, samples were drawn and analyzed by an AVL Opti CCA (Roche/Osmetech) every 4-8 hours for a period of 7 days, with calibration of each device at sample intervals. The data were plotted, and a least squares regression line was calculated. The average error for venous saturation of the CDI and Opticath after 72 hours was 3.86 and 9.51 respectively. At 168 hours, error for the CDI was 8.37, and the Opticath had an error of 14.78. A correlation analysis of the CDI and AVL CCA analyzer yielded a correlation coefficient of r = .88 at 72 hours and r = .84 at 168 hours. Correlation between the Opticath and the AVL CCA yielded a correlation coefficient of r = .77 at 72 hours and r = .55 at 168 hours. Based on these findings, the CDI 500 is an effective tool for monitoring venous blood saturation under simulated conditions of ECMO. Keywords: CDI 500, Opticath, extracorporeal membrane oxygenation, venous saturation.     

ECMO联合应用期间CRRT非计划性下机的预测模型构建

目的 探讨体外膜肺氧合（ECMO）联合应用期间连续性肾脏替代治疗（CRRT）非计划性下机的影响因素,构建预测模型并评价其效能。方法 选择呼吸重症监护病房行ECMO联合CRRT治疗的45例患者,统计ECMO联合应用期间CRRT发生非计划性下机的例次,对比计划下机组和非计划性下机组指标,采用logistic回归方程构建预测模型,运用ROC曲线下面积检验模型预测效果。结果 45例患者共行ECMO联合CRRT治疗343例次,其中无明确诱因的CRRT非计划性下机为212例次（61.8%）,logistic回归分析显示,CRRT血流速度（OR=0.924）、ECMO血流速度（OR=1.706）及ECMO模式（OR=4.764）是ECMO联合应用期间CRRT非计划性下机的预测因子,预测模型ROC曲线下面积为0.812,灵敏度0.825,特异度0.696,最大约登指数0.521,预测模型拟合优势比χ²=10.113,P=0.257。结论 本预测模型效果良好,临床医务人员在ECMO联合CRRT治疗期间,可结合预测模型做好运行监测并进行针对性处理。     

Pediatric cardiac extracorporeal membrane oxygenation in congenital heart disease: the cardiologist's view

Abstract: There is no doubt that extracorporeal membrane oxygenation (ECMO) as a powerful therapeutic modality in critically ill newborn infants and older children with congenital heart disease has implications for the pediatric cardiologist. His responsibilities as consultant in the intensive care unit include screening for unsuspected cyanotic heart disease in neonatal candidates referred for ECMO and appraisal of surgical repair in postcardiotomy patients as well as assessment of postoperative hemodynamics and detection of complications during perfusion. A close cooperation between intensive care specialists and other appropriate specialists (pediatric cardiologists, cardiac surgeons, and anesthesiologists) is required for the process of decision making prior to initiation of postoperative ECMO in the individual patient with congenital heart disease. Long-term survival, morbidity, cerebrovascular complications, and neurodevelopmental sequelae of these near miss children remain a critical issue. Furthermore, there is a strong need for professional psychosocial support of affected parents, both in the hospital and after discharge.     

Bloodless extracorporeal membrane oxygenation in the Jehovah's Witness patient

The successful use of prolonged extracorporeal life support with a heart-lung machine was first performed in 1972, as described by Hill et al., on a young man with post-traumatic respiratory failure. The first successful use of extracorporeal membrane oxygenation (ECMO) was 1976 by Bartlett et al. Since this time, the use of ECMO for neonatal and pediatric pulmonary support has become a standard of care in many children's hospitals. The use of ECMO, being a very invasive procedure, is not without risk. In our experience, most patients require multiple transfusions of the different blood components (packed red blood cells, plasma, platelets, and cryoprecipitate). Exposure to one or more blood products often occurs with connection to the ECMO circuit, as the circuit is generally primed with blood products or whole blood. Jehovah's Witnesses (JWs) are known best in the medical community for their refusal of blood products, even at the risk of death, which presents challenges for health care providers. This belief stems from the biblical passages that have been quoted as forbidding transfusion: Genesis 9:3-4, Leviticus 17:13-14, and Acts 15:19-21. This refusal of blood poses even greater challenges when treating the pediatric JW population. When a blood product is deemed medically necessary for the JW patient, the healthcare provider must either seek legal intervention, or support the patient's/family's wishes and associated outcome. This ethical dilemma may be further complicated in the setting of therapies, which may pose additional risks and potentially less clear benefit such as with ECMO. Bloodless cardiac surgery with cardiopulmonary bypass has been reported in the JW population in adults and pediatrics, including neonates. After a thorough search of the literature, no published report of a JW patient being supported on ECMO without blood or blood component utilization was identified. This case report will present our experience with multiple day, bloodless ECMO support of a 17-year-old male patient of the JW faith.     

Neonatal and pediatric extracorporeal membrane oxygenation using nonocclusive blood pumps: the Vienna experience

Neonatal and pediatric extracorporeal membrane oxygenation (ECMO) is carried out commonly using occlusive blood pumps. Centrifugal pumps provide simple and safe technology for transportation on ECMO. The assistence respiratoire extra corporelle (AREC) system enables single needle venovenous ECMO for infants. We report on our experience with neonatal and pediatric ECMO treatments using nonocclusive blood pumps. One-hundred forty-six ECMO treatments were performed for cardiac, neonatal, and pediatric indications in 54, 19, and 27% of cases. Centrifugal pumps were used in 99, and the AREC system in 42 cases. Hospital mortality was estimated retrospectively and influence of type of pump, type of ECMO belonging to indication group, and lactate at ECMO installation were estimated. Irreversible organ failure leading to ECMO termination was investigated within groups of indications. Survival (recent 50 ECMO treatments) was 80, 70, 43, and 30% after meconium aspiration syndrome, acute respiratory distress syndrome, cardiac surgery, and prolonged resuscitation. Lactate exceeding 100 mg/dl at ECMO installation predicted significantly worse outcome. Cerebral damage was the main reason for ECMO termination in all but persistent circulatory failure in the cardiac group. Myocardial recovery resulted in all except 2 cardiac cases. Nonocclusive blood pumps can be used safely in neonatal and pediatric ECMO. Early installation may improve outcome markedly. In cardiac cases results of surgery should be thoroughly investigated on the table before ECMO installation to prevent hopeless ECMO treatments.     

Pressure ulcers in paediatric patients on extracorporeal membrane oxygenation

It has been shown that pressure ulcer formation in critically ill paediatric patients increases morbidity and mortality. We sought to identify factors associated with pressure ulcer formation in paediatric patients on extracorporeal membrane oxygenation (ECMO). From December 2014 to 2015, we identified patients at our institution who developed a pressure ulcer to create two cohorts: ulcer and no ulcer. Variables of interest included: type of ECMO, ECMO indication, hours on ECMO, location of cannulas, volume of crystalloid and blood products received during the first 7 days or during the length of the ECMO run, albumin and lactate levels on the day of cannulation, and presence of vasopressor support or steroid therapy. Of 43 patients studied, 11 (25.5%) developed a pressure ulcer. Patients that developed ulcers were older (P = 0.001) and weighed more (P = 0.006). Femoral cannulation was more frequent in the ulcer group (36.4% vs 6.3%, P = 0.029), and duration of ECMO was longer (P = 0.007). Age, weight, duration of ECMO, and femoral cannulation may contribute to the development of pressure ulcers in children who require ECMO support. Further analysis is imperative to identify specific techniques and protocols that will prevent pressure ulcers in this critically ill population.     

Proposed entry criteria for postoperative cardiac extracorporeal membrane oxygenation after pediatric open heart surgery

While extracorporeal membrane oxygenation (ECMO) is being used increasingly after pediatric cardiac surgery, criteria are lacking for initiating ECMO after bypass weaning. To develop clinically useful ECMO entry criteria based on parameters readily available, children were examined at postoperative pediatric intensive care unit (PICU) admission. Using hospital mortality as the primary outcome, univariate and multiple logistic regressions were performed to estimate the predictive value of clinical (age, weight, and diagnosis) and laboratory (arterial blood pressure, pH, lactate, creatine kinase, and arterial and central venous oxygen saturation [ScvO2]) variables. Data from 218 children over a 2 year period were analyzed retrospectively. Univariate regression demonstrated that age, weight, diagnosis, blood pressure, venous and arterial saturation, and lactate were significantly associated with postoperative mortality (p < 0.05). In multiple regression, ScvO2 and lactate level were found to be independent predictors and were used in a predictive model (ScvO2 odds ratio: 2.03-828.6, p = 0.016) (lactate odds ratio: 1.58 -4.20, p = 0.0002) (R2 = 0.70). Applying an 80% risk of mortality to establish entry criteria as in neonatal ECMO, PICU admission values of lactate > 70 mg/dl if ScvO2 < 60% or lactate >163 mg/dl if ScvO2 > 60% are proposed to serve as postoperative ECMO entry criteria if bypass weaning has been possible but is followed by low cardiac output.