Simulated cardiopulmonary bypass: a high fidelity model for developing and accessing clinical perfusion skills.

BACKGROUND: Traditionally, novice perfusionists learn and practice clinical skills, during live surgical procedures. The profession's accrediting body is directing schools to implement simulated cardiopulmonary bypass (CPB) into the curriculum. Unfortunately, no CPB simulation models have been validated. Here we describe the design and application of a CPB simulation model. METHODS: A CPB patient simulator was integrated into a representative operative theater and interfaced with a simple manikin, a heart-lung machine (HLM), clinical perfusion circuitry, and equipment. Participants completed a simulation scenario designed to represent a typical CPB procedure before completing an exit survey to assess the fidelity and validity of the experience. Questions were scored using a 5-point Likert scale. RESULTS: Participants (n = 81) contributed 953 opinions on 40 questions. The participants reported that the model of simulated CPB (1) realistically presented both the physiologic and technical parameters seen during CPB (n = 347, mean 4.37, SD 0.86), (2) accurately represented the psychological constructs and cognitive mechanisms of the clinical CPB (n = 139, mean 4.24, SD 1.08), (3) requires real clinical skills and reproduces realistic surgical case progression (n = 167, mean 4.38, SD 0.86), and (4) would be effective for teaching, practicing, and assessing the fundamental skills of CPB (n = 300, mean 4.54, SD 0.9). Participants agreed that their performance in the simulation scenario accurately predicted their performance in a real clinical setting (n = 43, mean 4.07, SD 1.03) CONCLUSION: This novel simulation model of CPB reproduces the salient aspects of clinical CPB and may be useful for teaching, practicing, and assessing fundamental skills.

Effect of low dose acetylsalicylic acid and anticoagulant on clinical outcomes in COVID-19, analytical cross-sectional study.

Background and aims: The therapeutic strategy for the treatment of known sequelae of COVID-19 has shifted from reactive to preventative. In this study, we aim to evaluate the effects of acetylsalicylic acid (ASA), and anticoagulants on COVID-19 related morbidity and mortality. Methods: This record-based analytical cross-sectional study targeted 539 COVID-19 patients in a single United States medical center between March and December 2020. Through a random stratified sample, we recruited outpatient (n = 206) and inpatient (n = 333) cases from three management protocols, including standard care (SC) (n = 399), low-dose ASA only (ASA) (n = 112), and anticoagulation only (AC) (n = 28). Collected data included demographics, comorbidities, and clinical outcomes. The primary outcome measure was inpatient admission. Exploratory secondary outcome measures included length of stay, 30-day readmission rates, medical intensive care unit (MICU) admission, need for mechanical ventilation, the occurrence of acute respiratory distress syndrome (ARDS), bleeding events, clotting events, and mortality. The collected data were coded and analyzed using standard tests. Results: Age, mean number of comorbidities, and all individual comorbidities except for asthma, and malignancy were significantly lower in the SC compared to ASA and AC. After adjusting for age and comorbidity via binary logistic regression models, no statistical differences were found between groups for the studied outcomes. When compared to the SC group, ASA had lower 30-day readmission rates (odds ration [OR] 0.81 95% confidence interval [CI] 0.35-1.88, p = 0.63), MICU admission (OR 0.63 95% CI 0.34-1.17, p = 0.32), ARDS (OR 0.71 95% CI 0.33-1.52, p = 0.38), and death (OR 0.85 95% CI 0.36-1.99, p = 0.71). Conclusion: Low-dose ASA has a nonsignificant but potentially protective role in reducing the risk of COVID-19 related morbidity and mortality. Our data suggests a trend toward reduced 30-day readmission rates, ARDS, MICU admissions, need for mechanical ventilation, and mortality compared to the standard management protocol. Further randomized control trials are needed to establish causal effects.

Validation of transcutaneous carbon dioxide monitoring using an artificial lung during adult pulsatile cardiopulmonary bypass.

Measurements of transcutaneous carbon dioxide (tcCO2) have been used in multiple venues, such as during procedures utilizing jet ventilation, hyperbaric oxygen therapy, as well as both the adult and neo-natal ICUs. However, tcCO2 measurements have not been validated under conditions which utilize an artificial lung, such cardiopulmonary bypass (CPB). The purpose of this study was to (1) validate the use of tcCO2 using an artificial lung during CPB and (2) identify a location for the sensor that would optimize estimation of PaCO2 when compared to the gold standard of blood gas analysis.tcCO2 measurements (N = 185) were collected every 30 min during 54 pulsatile CPB procedures. The agreement/differences between the tcCO2 and the PaCO2 were compared by three sensor locations. Compared to the earlobe or the forehead, the submandibular PtcCO2 values agreed best with the PaCO2 and with a median difference of -.03 mmHg (IQR = 5.4, p < 0.001). The small median difference and acceptable IQR support the validity of the tcCO2 measurement. The multiple linear regression model for predicting the agreement between the submandibular tcCO2 and PaCO2 included the SvO2, the oxygenator gas to blood flow ratio, and the native perfusion index (R2 = 0.699, df = 1, 60; F = 19.1, p < 0.001).Our experience in utilizing tcCO2 during CPB has demonstrated accuracy in estimating PaCO2 when compared to the gold standard arterial blood gas analysis, even during CO2 flooding of the surgical field.

Ultrafiltration and cardiopulmonary bypass associated acute kidney injury: A systematic review and meta-analysis.

BACKGROUND: Cardiopulmonary bypass is known to raise the risk of acute kidney injury (AKI). Previous studies have identified numerous risk factors of cardiopulmonary bypass including the possible impact of perioperative ultrafiltration. However, the association between ultrafiltration (UF) and AKI remains conflicting. Thus, we conducted a meta-analysis to further examine the relationship between UF and AKI. HYPOTHESIS: Ultrafiltration during cardiac surgery increases the risk of developping Acute kidney Injury. METHODS: We searched PubMed, Web of Science, EBSCO, and SCOPUS through July 2021. The RevMan (version 5.4) software was used to calculate the pooled risk ratios (RRs) and mean differences along with their associated confidence intervals (95% CI). RESULTS: We identified 12 studies with a total of 8005 patients. There was no statistically significant difference in the incidence of AKI between the group who underwent UF and the control group who did not (RR = 0.90, 95% CI = 0.64-1). Subgroup analysis on patients with previous renal insufficiency also yielded nonsignificant difference (RR = 0.84, 95% CI = 0.53 -1.33, p = .47). Subgroup analysis based on volume of ultrafiltrate removed (> or <2900 ml) was not significant and did not increase the AKI risk as predicted (RR = 0.82, 95% CI = 0.63 -1.07, p = .15). We also did subgroup analysis according to the type of UF and again no significant difference in AKI incidence between UF groups and controls was observed in either the conventional ultrafiltration (CUF), modified ultrafiltration (MUF), zero-balanced ultrafiltration (ZBUF), or combined MUF and CUF subgroups. CONCLUSION: UF in cardiac surgery is not associated with increased AKI incidence and may be safely used even in baseline chronic injury patients.

Outcomes of adult patients supported by extracorporeal membrane oxygenation (ECMO) following cardiopulmonary arrest. The Mayo Clinic experience.

INTRODUCTION: To describe our experience in use of extracorporeal life support (ECLS) as a rescue strategy in patients following cardiopulmonary resuscitation. METHODS: A retrospective analysis was performed for patients (n = 101) who received ECLS after cardiorespiratory arrest between May 2001 and December 2014. The primary outcome was survival to hospital discharge. RESULTS: In this cohort median (IQR) age was 56 (37-67) years, 53 (53%) were male, and 90 (89%) were Caucasian. Ventricular tachycardia or ventricular fibrillations were the initial cardiac rhythm in 49 (48.5%) and asystole/pulseless electrical activity in 37 (36.8%). Median (IQR) time to initiation of extracorporeal support from arrest time was 72 (43-170) min. The median (IQR) duration of support was 100 (47-157) hours. Renal failure (66%) and bleeding (66%) were the two most commonly observed complications during ECLS support. The survival to hospital discharge was seen in 47 (47%) patients, and good neurologic outcome (mRs 0-3) was seen in 29%. Acidosis, lactate and continuous renal replacement therapy were independent predictors of mortality. The median (IQR) intensive care unit stay was 14 (4-28) days and hospital stay was 17 (4-35) days. CONCLUSION: Our institutional experience with ECLS as a rescue measure following cardiac arrest is associated with improvement in mortality, and favorable neurologic status at hospital discharge.

Acetylsalicylic Acid Compared with Enoxaparin for the Prevention of Thrombosis and Mechanical Ventilation in COVID-19 Patients: A Retrospective Cohort Study.

BACKGROUND AND OBJECTIVE: Low-dose acetylsalicylic acid (ASA, aspirin) is a well-known and frequently studied drug for primary and secondary prevention of disease due to its anti-inflammatory and coagulopathic effects. COVID-19 complications are attributed to the role of thrombo-inflammation. Studies regarding the use of low-dose ASA in COVID-19 are limited. For this reason, we propose that the use of low-dose ASA may have protective effects in COVID-19-related thromboembolism and lung injury. This study was conducted to assess the efficacy of low-dose ASA compared with enoxaparin, an anticoagulant, for the prevention of thrombosis and mechanical ventilation. METHODS: We conducted a retrospective cohort study on COVID-19-confirmed hospitalized patients at the Mansoura University Quarantine Hospital, outpatients, and home-isolated patients from September to December 2020 in Mansoura governorate, Egypt. Binary logistic regression analysis was used to assess the effect of ASA compared with enoxaparin on thromboembolism, and mechanical ventilation needs. RESULTS: This study included 225 COVID-19 patients. Use of ASA-only (81-162 mg orally daily) was significantly associated with reduced thromboembolism (OR 0.163, p = 0.020), but both low-dose ASA and enoxaparin, and enoxaparin-only (0.5 mg/kg subcutaneously (SC) daily as prophylactic dose or 1 mg/kg SC every 12 hours as therapeutic dose) were more protective (odds ratio [OR] 0.010, OR 0.071, respectively, p < 0.001). Neither ASA-only nor enoxaparin-only were associated with a reduction in mechanical ventilation needs. Concomitant use of low-dose ASA and enoxaparin was associated with reduced mechanical ventilation (OR 0.032, 95% CI 0.004-0.226, p = 0.001). CONCLUSIONS: Low-dose ASA-only use may reduce the incidence of COVID-19-associated thromboembolism, but the reduction may be less than that of enoxaparin-only, and both ASA and enoxaparin. Concomitant use of ASA and enoxaparin demonstrates promising results with regard to the reduction of thrombotic events, and mechanical ventilation needs.

Rationales and uncertainties for aspirin use in COVID-19: a narrative review.

OBJECTIVES: To review the pathophysiology of COVID-19 disease, potential aspirin targets on this pathogenesis and the potential role of aspirin in patients with COVID-19. DESIGN: Narrative review. SETTING: The online databases PubMed, OVID Medline and Cochrane Library were searched using relevant headlines from 1 January 2016 to 1 January 2021. International guidelines from relevant societies, journals and forums were also assessed for relevance. PARTICIPANTS: Not applicable. RESULTS: A review of the selected literature revealed that clinical deterioration in COVID-19 is attributed to the interplay between endothelial dysfunction, coagulopathy and dysregulated inflammation. Aspirin has anti-inflammatory effects, antiplatelet aggregation, anticoagulant properties as well as pleiotropic effects on endothelial function. During the COVID-19 pandemic, low-dose aspirin is used effectively in secondary prevention of atherosclerotic cardiovascular disease, prevention of venous thromboembolism after total hip or knee replacement, prevention of pre-eclampsia and postdischarge treatment for multisystem inflammatory syndrome in children. Prehospital low-dose aspirin therapy may reduce the risk of intensive care unit admission and mechanical ventilation in hospitalised patients with COVID-19, whereas aspirin association with mortality is still debatable. CONCLUSION: The authors recommend a low-dose aspirin regimen for primary prevention of arterial thromboembolism in patients aged 40-70 years who are at high atherosclerotic cardiovascular disease risk, or an intermediate risk with a risk-enhancer and have a low risk of bleeding. Aspirin's protective roles in COVID-19 associated with acute lung injury, vascular thrombosis without previous cardiovascular disease and mortality need further randomised controlled trials to establish causal conclusions.

The Effectiveness of Three Different Curricular Models to Teach Fundamental ECMO Specialist Skills to Entry Level Perfusionists.

The dramatic increase in the use of extracorporeal membrane oxygenation (ECMO) over the last decade with the concomitant need for ECMO competent perfusionists has raised questions of how well perfusion education programs are preparing entry-level perfusionists to participate in ECMO. While all perfusion schools teach ECMO principles, there is no standardized or systematic approach to the delivery of didactic knowledge and clinical skills in ECMO. Given this variability of ECMO education across and within perfusion schools, the CES-A exam may provide a metric for comparing curricular approaches. The purpose of this study is to examine three different curricular approaches to prepare new perfusion graduates to master the Adult ECMO Specialist Certification exam (CES-A). We examined three different curricular approaches to prepare new perfusion graduates to master the Adult ECMO Specialist Certification exam (CES-A). We hypothesized that there would be no difference in CES-A pass rate, exam score, Rasch measure, and item category scores between SUNY Cardiovascular Perfusion Program (CVP) graduates who completed SUNY's ECMO Capstone experience (Group III) and CVP graduates who did not select the ECMO Capstone experience (Group II). Further, we studied the performance of a third group of new graduates from an external program that does not offer formal ECMO courses or an ECMO Capstone experience (Group I). Every perfusion graduate in all groups passed the adult ECMO specialist exam. The graduates who as students completed an ECMO Capstone experience (Group III) scored higher on the exam and significantly higher on four exam categories: coagulation and hemostasis (p = .058), lab analysis point of care (p = .035), and monitor patient and circuit (p = .073), and the safety and failure modes (p = .017). Overall the median graduate Rasch measures ranked with Group III demonstrating the highest measure to Group I the lowest measures (not significant at p = .085). There is a positive educational effect due to CVP graduates completion of the ECMO Capstone experience compared to the program standard ECMO-related curricula in the two perfusion programs participating in this study. From this observation a structured ECMO simulation-based program appears to be equally effective as a traditional, typical lecture-only, clinical perfusion preceptorship, while demonstrating a more satisfactory experience with a higher reported case experience. In this study the standard perfusionist education curriculum prepared the new graduate to be successful on the CES-A exam. The three curricular approaches appear to prepare perfusionist graduates to be successful on the Adult ECMO Specialist exam.

The Fundamental Skills and Deconstructed Sub-Steps of Pediatric Cardiopulmonary Bypass.

Perfusion education programs use simulation to provide students with clinical skills prior to entering the operating room. To teach the psychomotor execution of skills in a simulation lab requires a list of validated skills and deconstructed sub-steps to fully optimize adult learning. A list of the fundamental skills of adult cardiopulmonary bypass (CPB) was recently published; however, no defined list exists regarding pediatric CPB skills. The purpose of this survey is to form a definitive list of skills fundamental to pediatric CPB. A survey of 23 proposed pediatric CPB clinical skills and 291 proposed skill sub-steps was developed. Proposed pediatric CPB skills were evaluated using an established frequency and harm index. If the skill is performed >50% of the time (frequency), and if >50% believe that if the skill is performed incorrectly patient harm is probable (risk), then the skill is accepted as fundamental. The survey content was validated by subject matter experts and then distributed to practicing perfusionists between September 2020 and December 2020. Of the 125 survey respondents, 57.9% had 10 or more years in the field. 35.2% of respondents are American Society of Extracorporeal Technology (AmSECT) Fellows of Pediatric Perfusion (FPP) and pediatric CPB represents >50% of the annual caseload for 69.7% of respondents. 22 of the 23 proposed skills were accepted as fundamental in the conduct of pediatric CPB and 258 of the 291 proposed sub-steps associated with CPB skills were accepted as integral to skill performance. By surveying practicing pediatric perfusionists, this study identifies 22 skills as fundamental to the safe execution of pediatric CPB. In addition, skill sub-elements were identified as necessary for skill execution. This knowledge will assist perfusion programs in developing a pediatric simulation curriculum that matches current clinical execution of pediatric skills.

Objective Content Validation of the Hemodynamic and Technical Parameters of the OrpheusTM Cardiopulmonary Bypass Simulator.

The utilization of simulators for training is increasing in the professions associated with cardiac surgery. Before applying these simulators to high-stakes assessment, the simulator's output data must be validated. The aim of this study is to validate a Cardiopulmonary Bypass (CPB) simulator by comparing the simulated hemodynamic and technical outputs to published clinical norms. Three Orpheus™ CPB simulators were studied and compared to a published reference of physiologic and technical metrics that are managed during clinical CPB procedures. The limits of the simulators user modifiable variables were interrogated across their full range and the results were plotted against the published clinical norms. The data generated with the simulator conforms to validated clinical parameters for patients between 50 and 110 kg. For the pre- and post-CPB periods, the independent variables of central venous pressure (CVP), heart rate (HR), contractility, and systemic vascular resistance (SVR) must be operated between the limits of 7 and 12 mmHg, 65 and 110 beats/min, 28% and 65%, and 6 and 32 units respectively. During full CPB the arterial pump flows should be maintained between 3.5 and 5.5 LPM and SVR between 18 and 38 units. Validated technical parameters during cardioplegia delivery are expected at solution flow rates between 250 and 400 mL/min and 100 and 225 mL/min for antegrade and retrograde delivery routes, respectively. We have identified the limits for user-modifiable settings that produce data conforming to the physiologic and technical parameter limits reported in the peer reviewed literature. These results can inform the development of simulation scenarios used for high stakes assessments of personnel, equipment, and technical protocols.

Survey of the Routine Practice Limits for Physiologic and Technical Parameters Managed by Clinical Perfusionists during Adult Cardiopulmonary Bypass.

Cardiopulmonary bypass (CPB) is a highly technical clinical discipline with a recognized variability in practice. Professional standards and guidelines documents help direct clinical practice and reduce variability, but these guidelines are necessarily vague and fall short of providing specific objective recommendations of clinical practice metrics. If clinical practice metrics were known, they would be informative when writing departmental policy manuals, structuring quality improvement initiatives, describing product R&D specifications, and designing educational assessment rubrics. Therefore, to address this gap, we conducted a national survey of clinical practice with the purpose of producing a benchmark of the typical variability of specific technical parameters that are commonly managed during adult CPB procedures. A pool of expert clinical perfusionists collaborated to compile a data set of normal ranges for 41 individual physiologic and technical parameters (pressures, flows, saturation, times, solutions, and temperatures) that are commonly managed during adult CPB procedures. Results were collected using an online survey application. Respondent demographics and measures of central tendency with descriptive quartile statistics and confidence intervals for each parameter are presented. Of the 335 people who participated in the survey, 315 met the inclusion criteria. The geographic demographics of the respondents were representative of the American Board of Cardiovascular Perfusion's distribution of certified clinical perfusionists. Of the 41 parameters investigated, there were 13 hemodynamic parameters, 13 normal flow rates and technical circuit parameters, 10 blood gasses and hematocrit parameters, and five parameters of patient temperatures. The data presented here are informative and provide a consensus-based objective assessment of the standard practice for adult CPB as reported by practicing clinical perfusionists. Based on these survey data, we have identified the typical clinical limits for the 41 parameters that are managed during adult CPB. This information may be incorporated into guiding documents to support the work of clinicians, researchers, and educators.

Development of the Adult ECMO Specialist Certification Examination.

The American Society of Extracorporeal Technology Board of Directors, consistent with the American Society of Extracorporeal Technology's safe patient care improvement mission, charged the International Board of Blood Management to write a knowledge and skill certification examination for healthcare personnel employed as adult extracorporeal membrane oxygenation (ECMO) specialists. Nineteen nationally recognized ECMO subject-matter experts were selected to complete the examination development. A job analysis was performed, yielding a job description and examination plan focused on 16 job categories. Multiple-choice test items were created and validated. Qualified ECMO specialists were identified to complete a pilot examination and both pre- and post-examination surveys. The examination item difficulty and candidate performance were ranked and matched using Rasch methodology. Candidates' examination scores were compared with their profession, training, and experience as ECMO specialists. The 120-item pilot examination form ranked 76 ECMO specialist candidates consistent with their licensure, ECMO training, and clinical experience. Forty-three registered nurses, 28 registered respiratory therapists, four certified clinical perfusionists, and one physician assistant completed the pilot examination process. Rasch statistics revealed examination reliability coefficients of .83 for candidates and .88 for test items. Candidates ranked the appropriateness for examination items consistent with the item content, difficulty, and their personal examination score. The pilot examination pass rate was 80%. The completed examination product scheduled for enrollment in March 2020 includes 100 verified test items with an expected pass rate of 84% at a cut score of 67%. The online certification examination based on a verified job analysis provides an extramural assessment that ranks minimally prepared ECMO specialists' knowledge, skills, and abilities (KSA) consistent with safe ECMO patient care and circuit management. It is anticipated that ECMO facilities and ECMO service providers will incorporate the certification examination as part of their process improvement, safety, and quality assurance plans.

Fundamental clinical skills of adult cardiopulmonary bypass: results of the 2017 national survey.

INTRODUCTION: Training students to become entry-level perfusionists requires evaluation and assessment of their clinical skills. While our professional organizations have compiled resources which identify the profession's knowledge base and categorical skills applied to clinical practice, these resources are lacking the necessary detail to develop validated clinical assessment rubrics. Therefore, the purpose of this project is to identify, through expert opinion, the detailed fundamental skills necessary to perform adult cardiopulmonary bypass (CPB). METHODS: We define a fundamental skill based upon frequency of use and risk of harm. A skill that experts report is conducted in >50% of their CPB cases - and, if not properly conducted, can cause harm, is deemed a fundamental skill. To identify these skills, a 73-question survey was developed and posted on PerfList and PerfMail from May 2017 to July 2017. RESULTS: The results from 261 respondents were analyzed. The demographics of the participants were representative of the workforce. Twenty skills were surveyed and all 20 met the criteria to be identified as a fundamental skill. Data regarding the actions, assessments and behaviors that may be associated with fundamental skills were also identified. CONCLUSIONS: Based upon this survey data, we have identified that there is consensus within our profession regarding the fundamental skills of adult CPB and a core body of actions, assessments and behaviors that experts perform when conducting these skills. This information may be incorporated into the entry-level educational process to inform curricula and design valid assessment rubrics.

Network specialization during adolescence: Hippocampal effective connectivity in boys and girls.

Adolescence is a complex period of concurrent mental and physical development that facilitates adult functioning at multiple levels. Despite the growing number of neuroimaging studies of cognitive development in adolescence focusing on regional activation patterns, there remains a paucity of information about the functional interactions across these participating regions that are critical for cognitive functioning, including memory. The current study used structural equation modeling (SEM) to determine how interactions among brain regions critical for memory change over the course of adolescence. We obtained functional MRI in 77 individuals aged 8-16 years old, divided into younger (ages 8-10) and older (ages > 11) cohorts, using an incidental encoding memory task to activate hippocampus formation and associated brain networks, as well as behavioral data on memory function. SEM was performed on the imaging data for four groups (younger girls, younger boys, older girls, and older boys) that were subsequently compared using a stacked model approach. Significant differences were seen between the models for these groups. Younger boys had a predominantly posterior distribution of connections originating in primary visual regions and terminating on multi-modal processing regions. In older boys, there was a relatively greater anterior connection distribution, with increased effective connectivity within association and multi-modal processing regions. Connection patterns in younger girls were similar to those of older boys, with a generally anterior-posterior distributed network among sensory, multi-modal, and limbic regions. In contrast, connections in older girls were widely distributed but relatively weaker. Memory performance increased with age, without a significant difference between the sexes. These findings suggest a progressive reorganization among brain regions, with a commensurate increase in efficiency of cognitive functioning, from younger to older individuals in both girls and boys, providing insight into the age- and gender-specific processes at play during this critical transition period.

Anticoagulation Management during First Five Days of Infant-Pediatric Extracorporeal Life Support.

Anticoagulation during infant-pediatric extracorporeal life support (ECLS) has been a topic of study for many years, but management of anticoagulation is still only partially understood. Adequate anticoagulation during ECLS is imperative for successful outcomes and understanding the individual variables that play part is crucial for properly implementing anticoagulation management strategies. The purpose of our study was to compare the relationships between the variables of activated partial thromboplastin time (aPTT), activated clotting time, international normalized ratio, bleeding, thrombus formation, kaolin + heparinase thromboelastograph alpha angle, kaolin thromboelastograph reaction time (KTEG R-time), heparin dose rates (HDR), antithrombin (AT), anti-Xa, bivalirudin dose rate, argatroban dose rate, interventions, and transfusions. We hypothesized that the relationship between measures of anticoagulation would be influenced by the AT levels, and a therapeutic aPTT (60-80 seconds) could be achieved by increasing, or maintaining, the overall AT above a specific threshold for infant-pediatric patients on ECLS. Thirty-five infant-pediatric patients underwent ECLS between January 2013 and January 2016. The median age was 39 days with an average weight of 3.9 ± 4.3 kg. ECLS parameters collected at least every 24 hours for the first five ECLS days. Parameters recorded by retrospective chart review were analyzed using linear regression and receiver operator characteristic (ROC) analysis. We were unable to report a significant correlation between optimal aPTT and HDR at various AT levels. However, ROC analysis suggested that to maintain an aPTT above 60 seconds, an AT threshold of 42% or higher was observed when the HDR was >12 U/kg/h ROC analysis also determined that no thrombus was associated with an aPTT >64 seconds and decreased bleeding was associated with a KTEG R-time below 30 minutes. Based on these findings, we report multiple correlations that may help develop future standardized infant-pediatric ECLS anticoagulation protocols.

Widespread occurrence and potential for biodegradation of bioactive contaminants in Congaree National Park, USA.

Organic contaminants with designed molecular bioactivity, such as pesticides and pharmaceuticals, originate from human and agricultural sources, occur frequently in surface waters, and threaten the structure and function of aquatic and terrestrial ecosystems. Congaree National Park in South Carolina (USA) is a vulnerable park unit due to its location downstream of multiple urban and agricultural contaminant sources and its hydrologic setting, being composed almost entirely of floodplain and aquatic environments. Seventy-two water and sediment samples were collected from 16 sites in Congaree National Park during 2013 to 2015, and analyzed for 199 and 81 targeted organic contaminants, respectively. More than half of these water and sediment analytes were not detected or potentially had natural sources. Pharmaceutical contaminants were detected (49 total) frequently in water throughout Congaree National Park, with higher detection frequencies and concentrations at Congaree and Wateree River sites, downstream from major urban areas. Forty-seven organic wastewater indicator chemicals were detected in water, and 36 were detected in sediment, of which approximately half are distinctly anthropogenic. Endogenous sterols and hormones, which may originate from humans or wildlife, were detected in water and sediment samples throughout Congaree National Park, but synthetic hormones were detected only once, suggesting a comparatively low risk of adverse impacts. Assessment of the biodegradation potentials of 8 14 C-radiolabeled model contaminants indicated poor potentials for some contaminants, particularly under anaerobic sediments conditions. Environ Toxicol Chem 2017;36:3045-3056. Published 2017 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.

Lean Flow: Optimizing Cardiopulmonary Bypass Equipment and Flow for Obese Patients-A Technique Article.

The goal of this chart review was to investigate the use of down-sized cardiopulmonary bypass (CPB) circuits for obese patients. The effects of transitioning from larger to smaller oxygenators, reservoirs, and arteriovenous tubing loops were evaluated through a retrospective review of 2,816 adult non-congenital procedure perfusion records. This technique report and case series is a continuation of our original prescriptive CPB circuit quality improvement project. An algorithm was derived to adjust body surface area (BSA) to lower body mass index (BMI) to provide down-sized extracorporeal circuit components capable of meeting the metabolic needs of the patient. As a result of using smaller circuits, decreased priming volumes led to significantly increased hemoglobin (HB) nadirs (p < .05) leading to significant decreases in homologous donor blood product exposures (p < .05). Patients with large BSAs were supported safely with smaller circuits by using lean body mass (LBM)-adjusted BSA and target blood flow algorithm. Based on this case series, large BMI patients may be safely supported with smaller circuits selected based on BSAs adjusted more toward LBM. Use of smaller circuits in high BMI patients led to higher HB nadirs and less donor blood components during the surgical procedure. Renal function and hospital stay were not affected by this approach.

Life history plasticity does not confer resilience to environmental change in the mole salamander (Ambystoma talpoideum).

Plasticity in life history strategies can be advantageous for species that occupy spatially or temporally variable environments. We examined how phenotypic plasticity influences responses of the mole salamander, Ambystoma talpoideum, to disturbance events at the St. Marks National Wildlife Refuge (SMNWR), FL, USA from 2009 to 2014. We observed periods of extensive drought early in the study, in contrast to high rainfall and expansive flooding events in later years. Flooding facilitated colonization of predatory fishes to isolated wetlands across the refuge. We employed multistate occupancy models to determine how this natural experiment influenced the occurrence of aquatic larvae and paedomorphic adults and what implications this may have for the population. We found that, in terms of occurrence, responses to environmental variation differed between larvae and paedomorphs, but plasticity (i.e. the ability to metamorphose rather than remain in aquatic environment) was not sufficient to buffer populations from declining as a result of environmental perturbations. Drought and fish presence negatively influenced occurrence dynamics of larval and paedomorphic mole salamanders and, consequently, contributed to observed short-term declines of this species. Overall occurrence of larval salamanders decreased from 0.611 in 2009 to 0.075 in 2014 and paedomorph occurrence decreased from 0.311 in 2009 to 0.121 in 2014. Although variation in selection pressures has likely maintained this polyphenism previously, our results suggest that continued changes in environmental variability and the persistence of fish in isolated wetlands could lead to a loss of paedomorphosis in the SMNWR population and, ultimately, impact regional persistence in the future.

Species interactions and the effects of climate variability on a wetland amphibian metacommunity.

Disentangling the role that multiple interacting factors have on species responses to shifting climate poses a significant challenge. However, our ability to do so is of utmost importance to predict the effects of climate change on species distributions. We examined how populations of three species of wetland-breeding amphibians, which varied in life history requirements, responded to a six-year period of extremely variable precipitation. This interval was punctuated by both extensive drought and heavy precipitation and flooding, providing a natural experiment to measure community responses to environmental perturbations. We estimated occurrence dynamics using a discrete hidden Markov modeling approach that incorporated information regarding habitat state and predator-prey interactions. This approach allowed us to measure how metapopulation dynamics of each amphibian species was affected by interactions among weather, wetland hydroperiod, and co-occurrence with fish predators. The pig frog, a generalist, proved most resistant to perturbations, with both colonization and persistence being unaffected by seasonal variation in precipitation or co-occurrence with fishes. The ornate chorus frog, an ephemeral wetland specialist, responded positively to periods of drought owing to increased persistence and colonization rates during periods of low-rainfall. Low probabilities of occurrence of the ornate chorus frog in long-duration wetlands were driven by interactions with predators due to low colonization rates when fishes were present. The mole salamander was most sensitive to shifts in water availability. In our study area, this species never occurred in short-duration wetlands and persistence probabilities decreased during periods of drought. At the same time, negative effects occurred with extreme precipitation because flooding facilitated colonization of fishes to isolated wetlands and mole salamanders did not colonize wetlands once fishes were present. We demonstrate that the effects of changes in water availability depend on interactions with predators and wetland type and are influenced by the life history of each of our species. The dynamic species occurrence modeling approach we used offers promise for other systems when the goal is to disentangle the complex interactions that determine species responses to environmental variability.