Laurance Lequier

Pediatric outcomes after extracorporeal membrane oxygenation for cardiac disease and for cardiac arrest: a review.

We reviewed reported survival and neurological outcomes, and predictors of these outcomes for pediatric cardiac extracorporeal membrane oxygenation (ECMO) and extracorporeal cardiopulmonary resuscitation (ECPR). We searched PubMed from 2000 to April 2011. Cumulative survival after cardiac ECMO in children was 788/1755 (45%); renal dysfunction, dialysis, neurologic complication, lactate, and ECMO duration consistently predicted this outcome, whereas single ventricle and ECPR did not. Neurological outcomes after cardiac ECMO were based on poorly described telephone questions in two studies for 47 patients with 51% significantly impaired and detailed follow-up testing for 42 patients in three studies with mental delay in 38% and mental score >85 (average or above) in 33%. Cumulative survival after ECPR in children was 371/762 (49%); noncardiac disease, renal dysfunction, neurologic complication, and pH on extracorporeal life support consistently predicted this outcome, whereas duration of CPR did not. Neurological outcomes after ECPR were based predominantly on the pediatric cerebral performance category (PCPC) score by chart review, with 161/181 (79%) having PCPC <2. No study reported detailed follow-up testing for survivors of ECPR. Survival outcomes of most cardiac subgroups were similar, except for concerning mortality in cavopulmonary connection patients. Priority areas for study include identification of potentially modifiable predictors of long-term outcomes.

Extracorporeal Membrane Oxygenation Circuitry

The extracorporeal membrane oxygenation circuit is made of a number of components that have been customized to provide adequate tissue oxygen delivery in patients with severe cardiac and/or respiratory failure for a prolonged period of time (days to weeks). A standard extracorporeal membrane oxygenation circuit consists of a mechanical blood pump, gas-exchange device, and a heat exchanger all connected together with circuit tubing. Extracorporeal membrane oxygenation circuits can vary from simple to complex and may include a variety of blood flow and pressure monitors, continuous oxyhemoglobin saturation monitors, circuit access sites, and a bridge connecting the venous access and arterial infusion limbs of the circuit. Significant technical advancements have been made in the equipment available for short- and long-term extracorporeal membrane oxygenation applications. Contemporary extracorporeal membrane oxygenation circuits have greater biocompatibility and allow for more prolonged cardiopulmonary support time while minimizing the procedure-related complications of bleeding, thrombosis, and other physiologic derangements, which were so common with the early application of extracorporeal membrane oxygenation. Modern era extracorporeal membrane oxygenation circuitry and components are simpler, safer, more compact, and can be used across a wide variety of patient sizes from neonates to adults.

Specificity of Radionuclide Brain Blood Flow Testing in Brain Death: Case Report and Review

Brain blood flow tests with diffusible radiopharmaceuticals are often done as an ancillary test in brain death (BD). We report a case of an infant with absent brain blood flow on an anterior planar image despite persistent breathing and extensor posturing. We reviewed the literature from 1980 to 2008 using MEDLINE and PubMed to determine the sensitivity and specificity of these tests in the diagnosis of BD. Search terms were any combination of: brain death; and single photon emission computed tomography (SPECT), radiopharmaceuticals, technetium Tc 99m exametazime, or organotechnetium compounds. The sensitivity of absent brain blood flow on planar imaging for clinically confirmed BD is 119/153 = 77.8% [95% CI 70.5%—83.7%]; and the specificity is 41/41 (100%) [95% CI 92.6%—100%]. For clinically confirmed BD, the sensitivity of SPECT is 107/121 (88.4%) [95% CI 81.4%—93.1%], and specificity is 12/12 (100%) [95% CI 78.4%—100%]. For contrast angiography confirmed BD, the sensitivity of SPECT is 34/34 (100%) [95% CI 91.2%—100%]; the specificity could not be estimated as there were no patients without clinical BD having both tests. Case reports emphasized the possibility of isolated posterior-fossa blood flow, which would not be detectable using non-diffusible radiopharmaceuticals, or without a lateral view using diffusible agents. We conclude that patients having an ancillary radiopharmaceutical brain blood flow test for BD should have anterior and lateral views without exception. Larger numbers of patients both with and without BD (but with severe brain injury) must be studied to determine the sensitivity and specificity of these tests.

Indications and outcomes in children receiving renal replacement therapy in pediatric intensive care.

PURPOSE We aimed to describe patient characteristics, indications for renal replacement therapy (RRT), and outcomes in children requiring RRT. We hypothesized that fluid overload, not classic blood chemistry indications, would be the most frequent reason for RRT initiation. MATERIALS AND METHODS A retrospective cohort study of all patients receiving RRT at a single-center quaternary pediatric intensive care unit between January 2004 and December 2008 was conducted. RESULTS Ninety children received RRT. The median age was 7 months (interquartile range, 1-83). Forty-six percent of patients received peritoneal dialysis, and 54% received continuous renal replacement therapy. The median (interquartile range) PRISM-III score was 14 (8-19). Fifty-seven percent had congenital heart disease, and 32% were on extracorporeal life support. The most common clinical condition associated with acute kidney injury was hemodynamic instability (57%; 95% confidence interval [CI], 46-67), followed by multiorgan dysfunction syndrome (17%; 95% CI, 10-26). The most common indication for RRT initiation was fluid overload (77%; 95% CI, 66-86). Seventy-three percent (95% CI, 62-82) of patients survived to hospital discharge. CONCLUSIONS Hemodynamic instability and multiorgan dysfunction syndrome are the most common clinical conditions associated with acute kidney injury in our population. In the population studied, the mortality was lower than previously reported in children and much lower than in the adult population.

Extracorporeal membrane oxygenation (ECMO) in severe adult respiratory distress syndrome

Severe adult respiratory distress syndrome (ARDS) remains associated with high mortality despite improved ventilatory techniques. While extracorporeal membrane oxygenation (ECMO) is not uncommon in neonatal/pediatric critical care, studies had yet to show similar benefits in adults. Therefore, the Conventional Ventilation or ECMO for Severe Adult Respiratory Failure (CESAR) Trial by Peek et al. was eagerly anticipated. It was the first randomized study of ECMO in adult patients in over 15 yr and the largest ever concerning this condition.

Survival and neurocognitive outcomes in pediatric extracorporeal-cardiopulmonary resuscitation

OBJECTIVE Extracorporeal Cardiopulmonary Resuscitation (E-CPR) is the initiation of extracorporeal life support during active chest compressions. There are no studies describing detailed neurocognitive outcomes of this population. We aim to describe the survival and neurocognitive outcomes of children who received E-CPR. METHODS Prospective cohort study. Children who received E-CPR at the Stollery Childrens Hospital between 2000 and 2010 were included. Neurocognitive follow-up, including Wechsler Preschool and Primary Scales of Intelligence, was completed at the age of 4.5 years, and at a minimum of 6 months after the E-CPR admission. RESULTS Fifty-five patients received E-CPR between 2000 and 2010. Children with cardiac disease had a 49% survival to hospital discharge and 43% survival at age 5-years, with no survivors (n=4) in those with non-cardiac disease. Pediatric E-CPR survivors had a mean (SD) Full Scale Intelligence quotient (FSIQ) score of 76.5 (15.9); with 4 children (24%) having intellectual disability (defined as FSIQ over 2 standard deviations below the population mean; i.e., <70). Multiple Cox regression analysis found that mechanical ventilation prior to E-CPR, open chest CPR, longer duration of CPR, low pH and more red blood cells given on the first day of ECMO, and longer time for lactate to normalize on ECMO were associated with higher mortality at age 5-years. CONCLUSION Pediatric patients with cardiac disease who required E-CPR had 43% survival at age 5 years. Of concern, the intelligence quotient in E-CPR survivors was significantly lower than the population mean, with 24% having intellectual disability.

Survival and Neurocognitive Outcomes After Cardiac Extracorporeal Life Support in Children Less Than 5 Years of AgeCLINICAL PERSPECTIVE

Background—Survival after pediatric cardiac extracorporeal life support (ECLS) is guarded, and neurological morbidity varies widely. Our objective is to report our 10-year experience with cardiac ECLS, including survival and kindergarten entry neurocognitive outcomes; to identify predictors of mortality or adverse neurocognitive outcomes; and to compare 2 eras, before and after 2005. Methods and Results—From 2000 to 2009, 98 children had venoarterial cardiac ECLS. Sixty-four patients (65%) survived to hospital discharge, and 50 (51%) survived ⩽5 years of age. Neurocognitive follow-up of survivors was completed at mean (SD) age of 52.9 (8) months using Wechsler Preschool and Primary Scale of Intelligence. Logistic regression analysis found the longer time (hours) for lactate to fall below 2 mmol/L on ECLS (hazard ratio, 1.39; 95% confidence interval, 1.05, 1.84; P=0.022), and the amount of platelets (mL/kg) given in the first 48 hours (hazard ratio, 1.18; 95% confidence interval, 1.06, 1.32; P=0.002) was independently associated with higher in-hospital mortality. Receiving ECLS after the year 2005 was independently associated with lower risk of in-hospital mortality (hazard ratio, 0.36; 95% confidence interval, 0.13, 0.99; P=0.048). Extracorporeal cardiopulmonary resuscitation was not independently associated with mortality or neurocognitive outcomes. Era was not independently associated with neurocognitive outcomes. The full-scale intelligence quotient of survivors without chromosomal abnormalities was 79.7 (16.6) with 25% below 2 SD of the population mean. Conclusions—Mortality has improved over time; time for lactate to fall on ECLS and volume of platelets transfused are independent predictors of mortality. Extracorporeal cardiopulmonary resuscitation and era were not independently associated with neurocognitive outcomes.

Diagnosis and management of circulatory arrest in pediatric ventricular assist device patients: Presentation of two cases and suggested guidelines

INTRODUCTION Pediatric patients supported by ventricular assist devices (VADs) are becoming more common. No guidelines exist to provide an approach to diagnosis or management of circulatory arrest in these patients. We present two case reports of apparent circulatory arrest in pediatric VAD-supported patients at our institution. DISCUSSION Diagnosis of circulatory arrest in VAD-supported patients can be challenging, especially with non-pulsatile flow devices. Traditional methods of diagnosis, such as pulse check and blood pressure, may be unreliable. Etiology may be primary device failure though other etiologies need to be considered. Treatment of the circulatory arrest depends on the etiology and type of VAD device being used. CONCLUSION In the absence of strong literature on the approach to these patients, we present these case reports and our local institutional guidelines as a starting point for discussion.

Survival and Neurocognitive Outcomes After Cardiac Extracorporeal Life Support in Children Less Than 5 Years of Age A Ten-Year Cohort

Background—Survival after pediatric cardiac extracorporeal life support (ECLS) is guarded, and neurological morbidity varies widely. Our objective is to report our 10-year experience with cardiac ECLS, including survival and kindergarten entry neurocognitive outcomes; to identify predictors of mortality or adverse neurocognitive outcomes; and to compare 2 eras, before and after 2005. Methods and Results—From 2000 to 2009, 98 children had venoarterial cardiac ECLS. Sixty-four patients (65%) survived to hospital discharge, and 50 (51%) survived ⩽5 years of age. Neurocognitive follow-up of survivors was completed at mean (SD) age of 52.9 (8) months using Wechsler Preschool and Primary Scale of Intelligence. Logistic regression analysis found the longer time (hours) for lactate to fall below 2 mmol/L on ECLS (hazard ratio, 1.39; 95% confidence interval, 1.05, 1.84; P=0.022), and the amount of platelets (mL/kg) given in the first 48 hours (hazard ratio, 1.18; 95% confidence interval, 1.06, 1.32; P=0.002) was independently associated with higher in-hospital mortality. Receiving ECLS after the year 2005 was independently associated with lower risk of in-hospital mortality (hazard ratio, 0.36; 95% confidence interval, 0.13, 0.99; P=0.048). Extracorporeal cardiopulmonary resuscitation was not independently associated with mortality or neurocognitive outcomes. Era was not independently associated with neurocognitive outcomes. The full-scale intelligence quotient of survivors without chromosomal abnormalities was 79.7 (16.6) with 25% below 2 SD of the population mean. Conclusions—Mortality has improved over time; time for lactate to fall on ECLS and volume of platelets transfused are independent predictors of mortality. Extracorporeal cardiopulmonary resuscitation and era were not independently associated with neurocognitive outcomes.

Prospective Side by Side Comparison of Outcomes and Complications With a Simple Versus Intensive Anticoagulation Monitoring Strategy in Pediatric Extracorporeal Life Support Patients

Objectives: A continuous infusion of unfractionated heparin is the most common anticoagulant used for pediatric patients on extracorporeal life support. The objective of this study was to compare extracorporeal life support complications and outcomes between two large-volume pediatric extracorporeal life support centers that use different anticoagulation strategies. Design: Prospective, observational cohort study. Setting: The University of Michigan used simple anticoagulation monitoring, whereas the University of Alberta used an intensive anticoagulation monitoring strategy. Patients: Pediatric patients on extracorporeal life support. Interventions: None. Measurements and Main Results: The primary outcome measure was major bleeding per extracorporeal life support run defined as bleeding that was retroperitoneal, pulmonary, or involved the CNS; bleeding greater than 20 mL/kg over 24 hours; or bleeding that required surgical intervention. Secondary outcomes measured were patient thrombosis per run, circuit thrombosis per run, and survival to hospital discharge per patient. Eighty-eight patients (95 runs) less than 18 years old were enrolled at the two centers over 2 years. The two centers enrolled different extracorporeal life support populations; University of Alberta enrolled more postcardiac surgical patients (74% vs 47%; p = 0.005). The indication for extracorporeal life support support also varied by center (p = 0.04). The two centers used similar proportions of VA extracorporeal life support (p = 0.3). Median (interquartile range) unfractionated heparin doses were similar between University of Michigan and University of Alberta, 30 (21–34) U/kg/hr and 26 (22–31) U/kg/hr, p value equals to 0.3, respectively. Median (interquartile range) antifactor Xa was lower in the University of Michigan cohort (0.23 [0.19–0.28] vs 0.41 [0.36–0.46] U/mL; p < 0.001). There was no significant difference in major bleeding (15% University of Michigan vs 21% University of Alberta; p = 0.6) or in patient thromboses (18% University of Michigan vs 13% University of Alberta; p = 0.5). There was no significant difference in survival to hospital discharge (University of Michigan 63% vs University of Alberta 73%; p = 0.1). Conclusions: Although this prospective cohort study compared different pediatric extracorporeal life support populations, the results did not identify a significant difference in outcomes between simple and intensive anticoagulation monitoring strategies.