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.

Objective: The aim of the study was to determine whether perforated appendicitis rates in children were influenced by the Coronavirus disease 2019 (COVID-19) surge. Background: Disruption of care pathways during a public health crisis may prevent children from obtaining prompt assessment for surgical conditions. Progression of appendicitis to perforation is influenced by timeliness of presentation. In the context of state-mandated controls and public wariness of hospitals, we investigated the impact of the COVID-19 outbreak on perforated appendicitis in children. Study Design: We conducted an analysis of all children presenting to 3 hospital sites with acute appendicitis between March 1 and May 7, 2020, corresponding with the peak COVID-19 outbreak in the New York City region. Control variables were collected from the same institutions for the preceding 5 years. The primary outcome measure was appendiceal perforation. Results: Fifty-five children presented with acute appendicitis over 10 weeks. Compared to a 5-year control cohort of 1291 patients, we observed a higher perforation rate (45% vs 27%, odds ratio 2.23, 95% confidence interval 1.29–3.85, P = 0.005) and longer mean duration of symptoms in children with perforations (71 ± 39 vs 47 ± 27 h, P = 0.001) during the COVID-19 period. There were no differences in perforation rates (55% vs 59%, P = 0.99) or median length of stay (1.0 vs 3.0 days, P = 0.58) among children screening positive or negative for SARS-CoV-2. Conclusions: Children in the epicenter of the COVID-19 outbreak demonstrated higher rates of perforated appendicitis compared to historical controls. Preoperative detection of SARS-CoV-2 was not associated with inferior outcomes. Although children likely avoid much of the morbidity directly linked to COVID-19, disruption to local healthcare delivery systems may negatively impact other aspects of pediatric surgical disease.

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The past two decades have witnessed an alarming expansion of staphylococcal disease caused by community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA). The factors underlying the epidemic expansion of CA-MRSA lineages such as USA300, the predominant CA-MRSA clone in the United States, are largely unknown. Previously described virulence and antimicrobial resistance genes that promote the dissemination of CA-MRSA are carried by mobile genetic elements, including phages and plasmids. Here, we used high-resolution genomics and experimental infections to characterize the evolution of a USA300 variant plaguing a patient population at increased risk of infection to understand the mechanisms underlying the emergence of genetic elements that facilitate clonal spread of the pathogen. Genetic analyses provided conclusive evidence that fitness (manifest as emergence of a dominant clone) changed coincidently with the stepwise emergence of (i) a unique prophage and mutation of the regulator of the pyrimidine nucleotide biosynthetic operon that promoted abscess formation and colonization, respectively, thereby priming the clone for success; and (ii) a unique plasmid that conferred resistance to two topical microbiocides, mupirocin and chlorhexidine, frequently used for decolonization and infection prevention. The resistance plasmid evolved through successive incorporation of DNA elements from non-S. aureus spp. into an indigenous cryptic plasmid, suggesting a mechanism for interspecies genetic exchange that promotes antimicrobial resistance. Collectively, the data suggest that clonal spread in a vulnerable population resulted from extensive clinical intervention and intense selection pressure toward a pathogen lifestyle that involved the evolution of consequential mutations and mobile genetic elements.