Clinical Outcomes After Tracheostomy in Children With Single Ventricle Physiology: Collaborative Research From the Pediatric Cardiac Intensive Care Society Multicenter Cohort, 2010-2021.

OBJECTIVES: Multicenter studies reporting outcomes following tracheostomy in children with congenital heart disease are limited, particularly in patients with single ventricle physiology. We aimed to describe clinical characteristics and outcomes in a multicenter cohort of patients with single ventricle physiology who underwent tracheostomy before Fontan operation. DESIGN: Multicenter retrospective cohort study. SETTING: Twenty-one tertiary care pediatric institutions participating in the Collaborative Research from the Pediatric Cardiac Intensive Care Society. PATIENTS: We reviewed 99 children with single ventricle physiology who underwent tracheostomy before the Fontan operation at 21 institutions participating in Collaborative Research from the Pediatric Cardiac Intensive Care Society between January 2010 and December 2020, with follow-up through December 31, 2021. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Death occurred in 51 of 99 patients (52%). Cox proportional hazard analysis was performed to determine factors associated with death after tracheostomy. Results are presented as hazard ratio (HR) with 95% CIs. Nonrespiratory indication(s) for tracheostomy (HR, 2.21; 95% CI, 1.14-4.32) and number of weeks receiving mechanical ventilation before tracheostomy (HR, 1.06; 95% CI, 1.02-1.11) were independently associated with greater hazard of death. In contrast, diagnosis of tricuspid atresia or Ebstein's anomaly was associated with less hazard of death (HR, 0.16; 95% CI, 0.04-0.69). Favorable outcome, defined as survival to Fontan operation or decannulation while awaiting Fontan operation with viable cardiopulmonary physiology, occurred in 29 of 99 patients (29%). Median duration of mechanical ventilation before tracheostomy was shorter in patients who survived to favorable outcome (6.1 vs. 12.1 wk; p < 0.001), and only one of 16 patients with neurologic indications for tracheostomy and 0 of ten patients with cardiac indications for tracheostomy survived to favorable outcome. CONCLUSIONS: For children with single ventricle physiology who undergo tracheostomy, mortality risk is high and should be carefully considered when discussing tracheostomy as an option for these children. Favorable outcomes are possible, although thoughtful attention to patient selection and tracheostomy timing are likely necessary to achieve this goal.

Carbapenem-resistant Enterobacterales among hospitalized patients in Cape Town, South Africa: clinical and microbiological epidemiology.

Background: Carbapenem-resistant Enterobacterales (CRE) are a substantial problem in Cape Town. CRE epidemiology is largely unknown and mortality remains high. Objectives: To describe and characterize the clinical and microbiological epidemiology of CRE within Cape Town hospitals to better inform therapy with regard to current and novel antibiotics, as well as improve antimicrobial stewardship (AMS), and infection prevention and control (IPC). Methods: This prospective, multicentre study performed between 1 November 2020 and 30 November 2022, across three public and three private hospitals included hospitalized participants with CRE from clinical cultures. Participant demographics, clinical information and microbiology results were collected and analysed. Results: Ninety percent of participants were from public hospitals. The age distribution ranged from 7 days to 88 years. Notable risk factors for CRE infection included recent exposure to antibiotics, medical devices and surgery. The most prevalent species was Klebsiella pneumoniae. However, a higher proportion of Serratia marcescens compared with previous reports was identified. The detected carbapenemases were blaOXA-48-like (80%) and blaNDM (11%). With the exception of amikacin (63%), tigecycline (65%), colistin (95%) and ceftazidime/avibactam (87%), susceptibility to antibiotics was low. Conclusions: This study identified common risk factors for CRE infection and generated a description of carbapenemase enzymes, species distribution and antibiograms, enabling a better understanding of CRE epidemiology. This provides insights into transmission patterns and resistance determinants of CREs, beneficial to informing data-driven regional patient management, AMS and IPC strategies.

Carbapenem-resistant Klebsiella pneumoniae among hospitalized patients in Cape Town, South Africa: molecular epidemiology and characterization.

Background: The molecular epidemiology of carbapenem-resistant Enterobacterales in Cape Town remains largely unknown. Objectives: This study aimed to describe the molecular epidemiology, resistome, virulome and mobilome of carbapenem-resistant Klebsiella pneumoniae (CRKP) within Cape Town to guide therapy, antimicrobial stewardship and infection prevention and control practices. Methods: Eighty-five CRKP isolates from hospitalized patients underwent WGS as part of a prospective, multicentre, cross-sectional study, conducted between 1 November 2020 and 30 November 2022, across public-sector and private-sector hospitals in Cape Town, South Africa. Results: MLST revealed three novel types, ST6785, ST6786 and ST6787, while the most common were ST219, ST307, ST17, ST13 and ST2497. Different predominant clones were noted in each hospital. The most common carbapenemase gene was blaOXA-48-like, detected in 71% of isolates, with blaNDM detected in 5%. Notably, co-detection of two carbapenemase genes (blaOXA-48-like and blaNDM) occurred in 13% of isolates. The yersiniabactin siderophore was detected in 73% of isolates, and was most commonly associated with the ICEKp5 mobile element. All carbapenemases were located on plasmids. The genes blaOXA-181 and blaOXA-232 colocalized with a ColKP3 replicon type on assembled contigs in 83% and 100% of cases, respectively. Conclusions: CRKP epidemiology in Cape Town reflects institutionally dominant, rather than regional, clones. The most prevalent carbapenemase gene was blaOXA-48-like, in keeping with CRKP epidemiology in South Africa in general. Emerging clones harbouring both blaOXA-48-like and blaNDM, such as ST17, ST2497 and the novel ST6787, are a concern due to the limited availability of appropriate antimicrobial agents in South Africa.

The genomic characterization of carbapenem-resistant Serratia marcescens at a tertiary hospital in South Africa.

Background: Serratia marcescens is an opportunistic nosocomial pathogen, and recent reports have highlighted the rapid increase in multidrug resistance in this organism. There is a paucity in genomic data for carbapenem-resistant S. marcescens (CRSM). Methods: A retrospective cohort study describing laboratory-confirmed CRSM from a tertiary academic hospital in Cape Town, South Africa, for the period 2015-20, was performed. Stored CRSM and contemporary isolates were submitted for WGS using Illumina MiSeq, with the Nextera DNA Flex Library Preparation Kit. Sequence data were analysed in-house using srst2 and Tychus, and CRSM and contemporary isolates were compared. Results: Twenty-one CRSM and four contemporary isolates were sequenced and analysed. Twenty-four different resistance genes were identified, with all isolates having at least two resistance genes, and seventeen isolates harbouring three or more genes. This correlated well with phenotypic results. The blaOXA-48-like carbapenemase was the most common carbapenemase identified, in 86% (18/21) of CRSM. A core SNP difference tree indicated that the CRSM could be grouped into three clusters. Eleven isolates had shared plasmids. Several genes and SNPs were identified in the CRSM, which may putatively augment virulence, but this requires further functional characterization. Conclusions: A diverse resistome was observed in CRSM, which was also reflected phenotypically, with blaOXA-48-like the most commonly carbapenemase. Though distinct clusters were observed, no clonality was noted, and a limited number of isolates shared plasmids. This study provides genomic data for emerging CRSM and highlights the importance of ongoing genomic surveillance to inform infection prevention control and antimicrobial stewardship initiatives.

Staged vs Complete Repair in Tetralogy of Fallot With Pulmonary Atresia.

BACKGROUND: We sought to compare outcomes for infants with tetralogy of Fallot with pulmonary atresia (TOF/PA) and confluent pulmonary arteries who underwent staged or primary complete surgical repair. METHODS: This retrospective study included infants undergoing initial surgical intervention between 0 and 60 days of age with TOF/PA without aortopulmonary collaterals from 2009 to 2018 at 20 centers. The primary outcome was days alive and out of the hospital in the first year of life (DAOH365). Secondary outcomes were mortality at 1 year of age and a composite major complication outcome. Multivariable modeling with generalized estimating equations were used to compare outcomes between groups. RESULTS: Of 221 subjects, 142 underwent staged repair and 79 underwent primary complete repair. There was no significant difference in median DAOH365 between the staged and primary repair groups (317 days [interquartile range, 278-336] vs 338 days [interquartile range, 314-348], respectively; adjusted P = .13). Nine staged repair patients (7%) died in the first year of life vs 5 primary repair patients (6%; adjusted odds ratio, 1.00; 95% CI, 0.25-3.95). At least 1 major complication occurred in 37% of patients who underwent staged repair vs 41% of patients who underwent primary complete repair (P = .75), largely driven by the need for unplanned cardiac reinterventions. CONCLUSIONS: For infants with TOF/PA with confluent pulmonary arteries, a surgical strategy of staged or primary complete repair resulted in statistically similar DAOH365, early mortality, and morbidity.

Epidemiology of Gram-negative bacteria during coronavirus disease 2019. What is the real pandemic?

PURPOSE OF REVIEW: Bacterial infections play a key role in hospital outcomes during the coronavirus disease 2019 (COVID-19) pandemic. Nonetheless, the global impact on the epidemiology of Gram-negative bacteria (GNB) and antibiotic resistance has not been clearly established. RECENT FINDINGS: Multiple limitations exist in the current literature, in that substantial variability was observed with regard to methodology. Notwithstanding the heterogeneity, the evidence suggests that the COVID-19 pandemic had a substantial negative impact on global epidemiology with an increase in hospital-onset infections, associated with GNB. Similarly, an alarming increase in resistant GNB compared to prepandemic rates, was apparent. This was most evident for carbapenemase-producing Klebsiella pneumoniae (bloodstream infections), carbapenem-resistant Pseudomonas aeruginosa (ventilator-associated pneumonia), and carbapenem-resistant Acinetobacter baumannii (all infections). Significant variations were most apparent in the large, system-wide regional or national comparative assessments, vs. single-centre studies. Categorizing concurrent bacteria as co- or secondary-infections may be paramount to optimize standard of care. SUMMARY: The data from most studies signal the probability that COVID-19 accelerated resistance. However, multiple limitations intrinsic to interpretation of current COVID-19 data, prevents accurately quantifying collateral damage on the global epidemiology and antibiotic resistance amongst GNB. It is likely to be substantial and renewed efforts to limit further increases is warranted.

Acinetobacter baumannii complex, national laboratory-based surveillance in South Africa, 2017 to 2019.

OBJECTIVE: We aimed to provide an analysis of A. baumannii complex (ABC) isolated from blood cultures in South Africa. MATERIALS AND METHODS: ABC surveillance was conducted from 1 April 2017 to 30 September 2019 at 19 hospital sites from blood cultures of any age and sex. Organism identification was performed using the MALDI-TOF MS and antimicrobial susceptibility testing (AST), MicroScan Walkaway System. We confirmed colistin resistance with Sensititre, FRCOL panel, and selected for whole-genome sequencing. RESULTS: During the study period, we identified 4822 cases of ABC, of which 2152 cases were from 19 enhanced surveillance sites were reported during the enhanced surveillance period (1 August 2018 to 30 September 2019). Males accounted for 54% (2611/4822). Of the cases with known age, 41% (1968/4822) were infants (< 1-year-old). Seventy-eight percent (1688/2152) of cases had a known hospital outcome, of which 36% (602/1688) died. HIV status was known for 69% (1168/1688) of cases, and 14% (238/1688) were positive. Eighty-two percent (1389/1688) received antimicrobial treatment in admission. Three percent (35/1389) of cases received single colistin. Four percent (75/2033) were resistant to colistin. At least 75% of the isolates (1530/2033) can be classified as extensively drug-resistant (XDR), with resistance to most antibiotics except for colistin. The majority, 83% (20/24), of the colistin-resistant isolates were of the sequence type (ST) 1. Resistance genes, both plasmid- and chromosomal- mediated were not observed. Although all isolates had, nine efflux pump genes related to antimicrobial resistance. CONCLUSION: Our surveillance data contributed to a better understanding of the natural course of A. baumannii disease, the patient characteristics among infants, and the level of resistance. At least two-thirds of the isolates were extensively drug-resistant, and four percent of isolates were resistant to colistin.

Exploring the dynamic relationships between risk perception and behavior in response to the Coronavirus Disease 2019 (COVID-19) outbreak.

The relationships between risk perception and related behavior form a fundamental theme in risk analysis. Despite increasing attentions on the temporal dimension of risk perception and behavior in recent literature, the dynamic relationships between these two constructs remain understudied. Infectious disease outbreaks, such as the Coronavirus Disease 2019 (COVID-19) pandemic, provide a key setting for analyzing evolving perceptions of and responses to natural or human-induced hazards. The main objectives of this research are: (1) to assess temporal changes in cognitive and affective dimensions of perceived COVID-19 risk as well as related protective behavior; and (2) to explore the dynamic relationships between COVID-19 risk perception and behavioral responses. Timely data on changing risk perception and behavior related to the COVID-19 outbreak were collected through two series of online surveys from four major cities (Seattle, Los Angeles, Chicago, and New York City; N = 736) and the central Midwest region of the United States (N = 1240) respectively during March-August 2020. The analysis revealed that: (1) the cognitive and affective dimensions of perceived COVID-19 risk and preventive behavior all changed over time; (2) there were both within- and across-time correlations between COVID-19 risk perception indicators and preventive actions; and (3) preventive actions showed varied feedback effects on individual aspects of perceived COVID-19 risk over time. Findings from this research support and expand major conceptual approaches to changing relationships between risk perception and behavior, particularly the risk reappraisal hypothesis. The study also has useful implications for health risk management and future research directions.

Compliance With an Antibiotic Guideline for Suspected Ventilator-Associated Infection: The Ventilator-Associated INfection (VAIN2) Study.

OBJECTIVES: To evaluate a guideline for antibiotic decisions in children with suspected ventilator-associated infection. DESIGN: Prospective, observational cohort study conducted in 22 PICUs in the United States and Canada. SETTING: PICUs in 22 hospitals from April 2017 to January 2019. SUBJECTS: Children less than 3 years old on mechanical ventilation greater than 48 hours who had respiratory secretions cultured and antibiotics initiated for suspected ventilator-associated infection. INTERVENTIONS: After baseline data collection in children with suspected ventilator-associated infection (Phase 1), a consensus guideline was developed for advising antibiotic continuation or stopping at 48-72 hours (Phase 2) and implemented (Phase 3). Guideline-based antibiotic recommendations were provided to the treating clinicians once clinical and microbiologic data were available. Demographic and outcome data were collected, and guideline compliance and antibiotic utilization evaluated for Phase 1 and Phase 3. MEASUREMENTS AND MAIN RESULTS: Despite education and implementation efforts, guideline-concordant antibiotic management occurred in 158 of 227 (70%) Phase 3 subjects compared with 213 of 281 (76%) in Phase 1. Illness severity and positive respiratory cultures were the primary determinants of antibiotic continuation. For subjects with a positive respiratory culture but a score for which antibiotic discontinuation was recommended (score ≤ 2), only 27% of Phase 3 subjects had antibiotics discontinued. Antibiotic continuation was not associated with improved outcomes in these subjects and was associated with significantly longer duration of ventilation (median 5.5 d longer) and PICU stay (5 d longer) in the overall study population. Positive respiratory cultures were not associated with outcomes irrespective of antibiotic treatment. CONCLUSIONS: Antibiotic guideline efficacy and safety remain uncertain due to clinician failure to follow the guideline, instead primarily relying on respiratory culture results. Strategies to overcome clinician perceptions of respiratory cultures and other barriers will be vital for improving guideline adherence and antibiotic use in suspected ventilator-associated infection in future studies.

Epidemiology of Culture-confirmed Candidemia Among Hospitalized Children in South Africa, 2012-2017.

BACKGROUND: We aimed to describe the epidemiology of candidemia among children in South Africa. METHODS: We conducted laboratory-based surveillance among neonates (≤28 days), infants (29 days to <1 year), children (1-11 years) and adolescents (12-17 years) with Candida species cultured from blood during 2012-2017. Identification and antifungal susceptibility of viable isolates were performed at a reference laboratory. We used multivariable logistic regression to determine the association between Candida parapsilosis candidemia and 30-day mortality among neonates. RESULTS: Of 2996 cases, neonates accounted for 49% (n = 1478), infants for 27% (n = 806), children for 20% (n = 589) and adolescents for 4% (n = 123). The incidence risk at tertiary public sector hospitals was 5.3 cases per 1000 pediatric admissions (range 0.39-119.1). Among 2943 cases with single-species infections, C. parapsilosis (42%) and Candida albicans (36%) were most common. Candida auris was among the 5 common species with an overall prevalence of 3% (n = 47). Fluconazole resistance was more common among C. parapsilosis (55% [724/1324]) versus other species (19% [334/1737]) (P < 0.001). Of those with known treatment (n = 1666), 35% received amphotericin B deoxycholate alone, 32% fluconazole alone and 30% amphotericin B deoxycholate with fluconazole. The overall 30-day in-hospital mortality was 38% (n = 586) and was highest among neonates (43% [323/752]) and adolescents (43% [28/65]). Compared with infection with other species, C. parapsilosis infection was associated with a reduced mortality among neonates (adjusted odds ratio 0.41, 95% confidence interval: 0.22-0.75, P = 0.004). CONCLUSIONS: Candidemia in this setting mainly affected neonates and infants and was characterized by fluconazole-resistant C. parapsilosis with no increased risk of death.

The Feasibility of Studying Metabolites in PICU Multi-Organ Dysfunction Syndrome Patients over an 8-Day Course Using an Untargeted Approach.

Metabolites are generated from critical biological functions and metabolism. This pediatric study reviewed plasma metabolites in patients suffering from multi-organ dysfunction syndrome (MODS) in the pediatric intensive care unit (PICU) using an untargeted metabolomics approach. Patients meeting the criteria for MODS were screened for eligibility and consented (n = 24), and blood samples were collected at baseline, 72 h, and 8 days; control patients (n = 4) presented for routine sedation in an outpatient setting. A subset of MODS patients (n = 8) required additional support with veno-atrial extracorporeal membrane oxygenation (VA-ECMO) therapy. Metabolites from thawed blood plasma were determined from ion pairing reversed-phase liquid chromatography-mass spectrometry (LC-MS) analysis. Chromatographic peak alignment, identification, relative quantitation, and statistical and bioinformatics evaluation were performed using MAVEN and MetaboAnalyst 4.0. Metabolite analysis revealed 115 peaks per sample. From the partial least squares-discriminant analysis (PLS-DA) with variance of importance (VIP) scores above ≥2.0, 7 dynamic metabolites emerged over the three time points: tauro-chenodeoxycholic acid (TCDCA), hexose, p-hydroxybenzoate, hydroxyphenylacetic acid (HPLA), 2_3-dihydroxybenzoic acid, 2-keto-isovalerate, and deoxyribose phosphate. After Bonferroni adjustment for repeated measures, hexose and p-hydroxybenzoate were significant at one time point or more. Kendall's tau-b test was used for internal validation of creatinine. Metabolites may be benign or significant in describing a patient's pathophysiology and require operator interpretation.

The Michigan Appropriateness Guide for Intravenous Catheters in Pediatrics: miniMAGIC.

OBJECTIVES: Vascular access device decision-making for pediatric patients remains a complex, highly variable process. To date, evidence-based criteria to inform these choices do not exist. The objective of the Michigan Appropriateness Guide for Intravenous Catheters in pediatrics (miniMAGIC) was to provide guidance on device selection, device characteristics, and insertion technique for clinicians, balancing and contextualizing evidence with current practice through a multidisciplinary panel of experts. METHODS: The RAND Corporation and University of California, Los Angeles Appropriateness Method was used to develop miniMAGIC, which included the following sequential phases: definition of scope and key terms, information synthesis and literature review, expert multidisciplinary panel selection and engagement, case scenario development, and appropriateness ratings by an expert panel via 2 rounds. RESULTS: The appropriateness of the selection, characteristics, and insertion technique of intravenous catheters commonly used in pediatric health care across age populations (neonates, infants, children, and adolescents), settings, diagnoses, clinical indications, insertion locations, and vessel visualization devices and techniques was defined. Core concepts including vessel preservation, insertion and postinsertion harm minimization (eg, infection, thrombosis), undisrupted treatment provision, and inclusion of patient preferences were emphasized. CONCLUSIONS: In this study, we provide evidence-based criteria for intravenous catheter selection (from umbilical catheters to totally implanted venous devices) in pediatric patients across a range of clinical indications. miniMAGIC also highlights core vascular access practices in need of collaborative research and innovation.

Development of an Antibiotic Guideline for Children With Suspected Ventilator-Associated Infections.

OBJECTIVES: To develop a guideline for the decision to continue or stop antibiotics at 48-72 hours after their initiation in children with suspected ventilator-associated infection. DESIGN: Prospective, multicenter observational data collection and subsequent development of an antibiotic guideline. SETTING: Twenty-two PICUs. PATIENTS: Children less than 3 years old receiving mechanical ventilation who underwent clinical testing and initiation of antibiotics for suspected ventilator-associated infection. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Phase 1 was a prospective data collection in 281 invasively ventilated children with suspected ventilator-associated infection. The median age was 8 months (interquartile range, 4-16 mo) and 75% had at least one comorbidity. Phase 2 was development of the guideline scoring system by an expert panel employing consensus conferences, literature search, discussions with institutional colleagues, and refinement using phase 1 data. Guideline scores were then applied retrospectively to the phase 1 data. Higher scores correlated with duration of antibiotics (p < 0.001) and higher PEdiatric Logistic Organ Dysfunction 2 scores (p < 0.001) but not mortality, PICU-free days or ventilator-free days. Considering safety and outcomes based on the phase 1 data and aiming for a 25% reduction in antibiotic use, the panel recommended stopping antibiotics at 48-72 hours for guideline scores less than or equal to 2, continuing antibiotics for scores greater than or equal to 6, and offered no recommendation for scores 3, 4, and 5. The acceptability and effect of these recommendations on antibiotic use and outcomes will be prospectively tested in phase 3 of the study. CONCLUSIONS: We developed a scoring system with recommendations to guide the decision to stop or continue antibiotics at 48-72 hours in children with suspected ventilator-associated infection. The safety and efficacy of the recommendations will be prospectively tested in the planned phase 3 of the study.

Emergence of plasmid-mediated colistin resistance (MCR-1) among Escherichia coli isolated from South African patients.

The polymyxin antibiotic colistin is an antibiotic of last resort for the treatment of extensively drug-resistant Gram-negative bacteria, including carbapenemase-producing Enterobacteriaceae. The State of the World's Antibiotics report in 2015 highlighted South Africa (SA)'s increasing incidence of these 'superbugs' (3.2% of Klebsiella pneumoniae reported from SA were carbapenemase producers), and in doing so, underscored SA's increasing reliance on colistin as a last line of defence. Colistin resistance effectively renders such increasingly common infections untreatable.

Emergency department use after stage II palliation for children with single ventricle lesions.

BACKGROUND: Infants born with a single cardiac ventricle require a 3-stage surgical palliation performed during the first few years of life for long-term survival. We aimed to determine the extent to which the emergency department services were used between the second and third surgical stages. METHODS: A retrospective chart review was performed on patients who underwent stage II palliation at our institution between 2006 and 2011. Data analyses were performed using Mann-Whitney U tests or χ tests as appropriate. RESULTS: Fifty patients underwent stage II palliation during the study period, 47 of which survived to hospital discharge. Thirty-one (66%) patients required 95 emergency department visits before stage III. The most common chief complaints were respiratory (n = 39) and gastrointestinal (n = 18 visits) in nature. Age and weight at time of stage II surgery, dominant ventricle, and data from discharge echocardiograms were not significantly different between patients who did and did not require emergency department visits. Median postoperative length of stay after stage II palliation was longer in patients using the emergency department, 11 (interquartile range, 6-17) versus 7 (interquartile range, 5-8) days, P = 0.015. Moreover, patients with lengths of stay greater than 10 days were 6 times more likely to require emergency department services (odds ratio, 6.0; 95% confidence intervals, 1.4-25.4). CONCLUSIONS: Emergency department use by patients with a single cardiac ventricle is common after their second surgical stage, especially in patients with more complicated postoperative courses. This study emphasizes the important role of the emergency department in the care of these challenging patients.

Necessity of temporary epicardial pacing wires after surgery for congenital heart disease.

BACKGROUND: Temporary epicardial pacing wires are commonly placed in patients undergoing surgery for congenital heart disease. Though often helpful, these wires are not without risk. We aimed to identify characteristics that would obviate placement of temporary epicardial pacing wires in this patient population. METHODS: A prospective observational study was performed on patients admitted to the pediatric intensive care unit after surgery for congenital heart disease between October 2011 and October 2012. Logistic regression analysis was performed to identify independent predictors of patients in whom wires were not helpful postoperatively. RESULTS: Wires were placed in 213 of 249 patients. Wires were helpful in 50 patients; 23 for diagnostic purposes only, 17 for therapeutic purposes only, and 10 for both. On logistic regression analysis, absence of intraoperative arrhythmias (p < 0.01), lower arteriovenous O2 difference (p < 0.01), and shorter duration of cardiopulmonary bypass (p = 0.050) were significant predictors of patients in whom wires were not helpful postoperatively. Further, the predicted probability based on logistic regression model using these 3 variables correctly identified 93% of patients who did not need pacing wires. Four complications (1.9%) related to wires occurred, including 1 episode of life-threatening bleeding that was found, during emergent exploration, to be due to atrial perforation at the wire insertion site. CONCLUSIONS: Temporary epicardial pacing wires are not necessary in many patients recovering from surgery for congenital heart disease. A conservative approach to their use may therefore be warranted.

Flexible bronchoscopy for children on extracorporeal membrane oxygenation for cardiac failure.

OBJECTIVE: To describe the safety and use of flexible bronchoscopy in the management of respiratory complications in patients on extracorporeal membrane oxygenation for cardiac failure. DESIGN: Retrospective cohort study. SETTING: Pediatric intensive care unit at a tertiary care university hospital. PATIENTS: Patients requiring extracorporeal membrane oxygenation for cardiac failure in the pediatric intensive care unit between 2003 and 2008. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Forty-eight patients required extracorporeal membrane oxygenation for cardiac failure (32 after surgery for congenital heart disease, 16 for acquired heart disease) during the study period. Seven patients (15%) underwent 17 flexible bronchoscopies. Median age and weight at extracorporeal membrane oxygenation cannulation was 10 days (range, 4 days to 27 yrs) and 3.2 kg (range, 2.8-66 kg), respectively. Median duration of extracorporeal membrane oxygenation in this group was longer than those not undergoing flexible bronchoscopy (314 vs. 114 hrs, p < .001). In all cases, flexible bronchoscopy indication was persistent atelectasis despite conventional ventilator adjustments. Activated clotting time during flexible bronchoscopy was maintained between 180 and 220 secs (normal, 80-150 secs) in all patients. No major complications occurred. A minor complication occurred in one of 17 flexible bronchoscopies (6%), scant oozing that stopped with epinephrine lavage. Findings included bronchus compression or narrowing in four patients and mucous plugging in three patients. Bronchoalveolar lavage specimens identified new ventilator-associated infections in three patients. In two patients with mucous plugging, serial bronchoscopies were accompanied by stepwise decreases in extracorporeal membrane oxygenation flow, thereby facilitating discontinuation from extracorporeal membrane oxygenation support. CONCLUSIONS: In patients requiring extracorporeal membrane oxygenation for cardiac failure, flexible bronchoscopy can be performed safely, provide important diagnostic information to the bedside clinician, and, perhaps, therapeutic benefit to the patient.

Emergence of endemic serogroup W135 meningococcal disease associated with a high mortality rate in South Africa.

BACKGROUND: In the African meningitis belt, Neisseria meningitidis serogroup W135 has emerged as a cause of epidemic disease. The establishment of W135 as the predominant cause of endemic disease has not been described. METHODS: We conducted national laboratory-based surveillance for invasive meningococcal disease during 2000-2005. The system was enhanced in 2003 to include clinical data collection of cases from sentinel sites. Isolates were characterized by pulsed-field gel electrophoresis and multilocus sequence typing. RESULTS: A total of 2135 cases of invasive meningococcal disease were reported, of which 1113 (52%) occurred in Gauteng Province, South Africa. In this province, rates of disease increased from 0.8 cases per 100,000 persons in 2000 to 4.0 cases per 100,000 persons in 2005; the percentage due to serogroup W135 increased from 7% (4 of 54 cases) to 75% (221 of 295 cases). The median age of patients infected with serogroup W135 was 5 years (interquartile range, 2-23 years), compared with 21 years (range, 8-26 years) for those infected with serogroup A (P<.001). The incidence of W135 disease increased in all age groups. Rates were highest among infants (age, <1 year), increasing from 5.1 cases per 100,000 persons in 2003 to 21.5 cases per 100,000 persons in 2005. Overall case-fatality rates doubled, from 11% in 2003 to 22% in 2005. Serogroup W135 was more likely to cause meningococcemia than was serogroup A (82 [28%] of 297 cases vs. 11 [8%] of 141 cases; odds ratio, 8.9, 95% confidence interval, 2.2-36.3). A total of 285 (95%) of 301 serogroup W135 isolates were identified as 1 clone by pulsed-field gel electrophoresis; 7 representative strains belonged to the ST-11/ET-37 complex. CONCLUSIONS: Serogroup W135 has become endemic in Gauteng, South Africa, causing disease of greater severity than did the previous predominant serogroup A strain.

Increased prevalence of severe malaria in HIV-infected adults in South Africa.

BACKGROUND: Conflicting reports exist regarding the impact of human immunodeficiency virus (HIV) infection on the risk of severe malaria. We aimed to assess the effect of HIV infection status, advancing immunosuppression, and antimalarial immunity on the severity of malaria. METHODS: A prospective cohort study was conducted. Consecutive hospitalized adult patients with falciparum malaria were tested for HIV antibodies and to determine CD4+ T cell count. Immunity to malaria was assessed by obtaining a history of childhood residence in an area where malaria is endemic. Patients were assessed for features of severe malaria. RESULTS: Three hundred thirty-six patients were enrolled in the study, of whom 32 (10%) had severe malaria. The prevalence of HIV infection was 33%, and 111 patients (33%) were nonimmune to malaria. HIV-infected patients complained more frequently about respiratory and abdominal symptoms and less frequently about rigors and headache. Risk factors for severe malaria determined by multivariate analysis included being nonimmune to malaria, having a positive HIV serostatus, having an elevated parasite count, and having an increased white blood cell count. Risk of severe malaria was increased in HIV-infected patients with a CD4+ T cell count of < 200 x 10(6) cells/L (P < or = .001). Nonimmune HIV-infected patients were significantly more likely to have severe malaria (13 [36%] of 36 patients) than were nonimmune non-HIV-infected patients (9 [12%] of 75 patients; odds ratio, 4.15 [95% confidence interval, 1.57-10.97]; P = .003). HIV serostatus did not affect risk of severe malaria in the group from an area with endemicity (5 [7%] of 74 HIV-infected patients had severe malaria, and 5 [3%] of 151 non-HIV-infected patients had malaria; P = .248). CONCLUSIONS: HIV-infected nonimmune adults are at increased risk of severe malaria. This risk is associated with a low CD4+ T cell count. This interaction is of great public health importance.