Understanding the Procedural Skills Needed in Rural Pediatric Practices: A Survey of Rural Pediatric Providers in the State of New Mexico.

OBJECTIVES: There is little data evaluating procedural skills in current rural pediatric practices. In order to prepare a cadre of pediatricians to work in rural settings, we require an understanding of the unique procedural skills needed by rural pediatric providers. Our objective was to determine how often pediatricians performed various procedural skills, determine the importance of these skills to current practice, and how they differ between rural and urban pediatric providers. METHODS: A survey evaluating pediatrician utilization of the 13 required Accreditation Council Graduate Medical Education procedural skills in current practice was developed and distributed to pediatric providers in New Mexico. Descriptive statistics were used to profile participants and describe survey responses. Chi-square tests were used to evaluate differences by urban setting or IHS. Fisher's exact test was employed to assess differences if cell sizes were less than five. All p-values were two sided with alpha=.05. Benjamini-Hochberg method was used to control for type 1 errors. RESULTS: Fifty-two of 216 pediatric providers responded. The majority surveyed performed each of the 13 procedures less than monthly but competency in many of these procedures is important. Thirty-two respondents submitted free-text responses recommending competence with tracheostomy changes, gastrostomy-tube changes/cares, and circumcision. CONCLUSION: Majority of surveyed pediatricians performed the required procedures less than monthly but deemed several procedures to be important. Rural pediatricians recommended specific procedural skills needed in rural practice. All trainees receive procedural skills training. However, trainees interested in rural practice may need additional training in specific skills different than their non-rural counterparts.

Pediatric Dilated Cardiomyopathy Patients Do Not Meet Traditional Cardiac Resynchronization Criteria.

INTRODUCTION: Cardiac resynchronization therapy (CRT) is an effective device-based intervention for adults with heart failure (HF) with specific indications, based on large, multicenter randomized clinical trials. The criteria for CRT in adult HF include significant symptoms, ventricular systolic dysfunction, prolonged QRS duration, and left bundle branch block (LBBB) pattern on electrocardiogram (ECG). Despite having less data, CRT is also being widely utilized in children with HF. The shortage of evidence-based CRT criteria in pediatrics prompted us to review a cohort of children with dilated cardiomyopathy and evaluate their potential eligibility for CRT using the traditional adult criteria. METHODS: Single-center data of all pediatric patients with dilated cardiomyopathy were extracted from the heart failure registry and retrospectively reviewed. Patients who had at least 2 separate visits that included HF scoring, electrocardiogram, and echocardiogram were included. Patients who were ventricular paced were excluded. RESULTS: Data for 52 patients meeting inclusion criteria were analyzed. The mean ejection fraction was 25% on the first clinical evaluation and 27% on the second visit. No patient and 2 patients met the adult criteria for prolonged QRS on the first and second encounters, respectively. No patients had an LBBB pattern on ECG. CONCLUSIONS: None of the pediatric HF patients in our study met the published Class I criteria for CRT device therapy in adults. These findings suggest that extrapolation of adult HF data to pediatrics is not sufficient for CRT criteria. Specific guidelines for device implantation in children must be based on scientific investigation including pediatric clinical trials.

Surgical cardiac denervation therapy for treatment of congenital ion channelopathies in pediatric patients: a contemporary, single institutional experience.

BACKGROUND: Congenital ion channel disorders, including congenital long QT syndrome (LQTS), cause significant morbidity in pediatric patients. When medication therapy does not control symptoms or arrhythmias, more invasive treatment strategies may be necessary. This study examines our institution's clinical experience with surgical cardiac denervation therapy for management of these arrhythmogenic disorders in children. METHODS: An institutional review board-approved retrospective review identified ten pediatric patients with congenital ion channelopathies who underwent surgical cardiac denervation therapy at a single institution between May 2011 and April 2014. Eight patients had a diagnosis of congenital LQTS, two patients were diagnosed with catecholaminergic polymorphic ventricular tachycardia (CPVT). All patients underwent sympathectomy and partial stellate ganglionectomy via video-assisted thoracoscopic surgery (VATS). RESULTS: Six of the ten patients had documented ventricular arrhythmias preoperatively, and 70% of the patients had preoperative syncope. The corrected QT interval decreased in 75% of patients with LQTS following sympathectomy. Postoperative arrhythmogenic symptoms were absent in 88% of congenital LQTS patients, but both patients with CPVT continued to have symptoms throughout the duration of follow-up. All patients were alive after a median follow-up period of 10 months. CONCLUSIONS: Surgical cardiac denervation therapy via VATS is a useful treatment strategy for congenital LQTS patients who fail medical management, and its potential benefit in the management of CPVT is unclear. A prospective comparison of the efficacy of surgical cardiac denervation therapy and implantable cardioverter-defibrillator use in congenital ion channelopathies is timely and crucial.

Management of pediatric tachyarrhythmias on mechanical support.

BACKGROUND: Pediatric patients with persistent arrhythmias may require mechanical cardiopulmonary support. We sought to classify the population, spectrum, and success of current treatment strategies. METHODS AND RESULTS: A multicenter retrospective chart review was undertaken at 11 sites. Inclusion criteria were (1) patients <21 years, (2) initiation of mechanical support for a primary diagnosis of arrhythmias, and (3) actively treated on mechanical support. A total of 39 patients were identified with a median age of 5.5 months and median weight of 6 kg. A total of 69% of patients were cannulated for supraventricular tachycardia with a median rate of 230 beats per minute. A total of 90% of patients were supported with extracorporeal membrane oxygenation for an average of 5 days. The remaining 10% were supported with ventricular assist devices for an average of 38 (20-60) days. A total of 95% of patients were treated with antiarrhythmics, with 43% requiring >1 antiarrhythmic. Amiodarone was the most frequently used medication alone or in combination. A total of 33% patients underwent electrophysiology study/transcatheter ablation. Radiofrequency ablation was successful in 9 patients on full flow extracorporeal membrane oxygenation with 3 radiofrequency-failures/conversion to cryoablation. One patient underwent primary cryoablation. A total of 15% of complications were related to electrophysiology study/ablation. At follow-up, 23 patients were alive, 8 expired, and 8 transplanted. CONCLUSIONS: Younger patients were more likely to require support in the presented population. Most patients were treated with antiarrhythmics and one third required electrophysiology study/ablation. Radiofrequency ablation is feasible without altering extracorporeal membrane oxygenation flows. There was a low frequency of acute adverse events in patients undergoing electrophysiology study/ablation, while on extracorporeal membrane oxygenation.

Long QT syndrome unmasked by dexmedetomidine: a case report.

Dexmedetomidine is a selective alpha-2 adrenergic agonist that is used frequently for short-term sedation in children. It has been noted to cause hypertension, hypotension, bradycardia, and sinus pauses; however, QTc prolongation has not been reported with dexmedetomidine administration. We describe a case of marked QT prolongation with use of dexmedetomidine in a pediatric critical care setting. Clinicians should be vigilant about potential QT prolongation in patients on dexmedetomidine, particularly in those receiving multiple other medications.

Novel finding of coronary ectasia in a case of acute rheumatic Fever.

A 10-year-old boy presented to his pediatrician with acute fever, rash, and polyarthritis. Laboratory studies revealed elevated inflammatory markers and positive throat culture. Echocardiogram demonstrated panvalvular insufficiency consistent with acute rheumatic fever (ARF) and coronary artery ectasia. This latter finding, typically associated with Kawasaki disease, has not been previously reported in ARF.

The poor performance of RSR' pattern on electrocardiogram lead V1 for detection of secundum atrial septal defects in children.

OBJECTIVE: To assess the accuracy of RSR' patterns in lead V1 (RSR'-V1) in diagnosing atrial septal defects (ASDs) in children. STUDY DESIGN: Children who underwent an electrocardiogram (ECG) during 2010 were divided into 2 ECG groups: RSR'-V1 and normal (no RSR'-V1). Children who underwent an echocardiogram during 2010 were also divided into an ASD group and a normal echocardiogram group. The 4 groups were matched in a 2 × 2 table format where the RSR'-V1 was the "test" and ASD was the "disease." Sensitivity, specificity, positive/negative predictive values, and pre/post-test probabilities were calculated. RESULTS: There were 4658 ECG studies included in the analysis: 836 had RSR'-V1 and 3822 were normal without RSR'-V1. Of 4935 echocardiographic studies analyzed, 329 had an ASD and 4606 were normal; 1363 patients had both studies done during the study period. The ECG sensitivity for diagnosing an ASD was 36.1%, specificity was 80%, positive predictive value was 14.7%, and negative predictive value was 92.9% with an overall accuracy of 76.2%. Patients with ASD and RSR'-V1 were significantly older than patients with ASD and no RSR'-V1 pattern. CONCLUSION: RSR'-V1 is a poor screening test for the detection of ASD. It should not change the clinical suspicion or the decision to obtain an echocardiogram. Older children without RSR'-V1 on ECG are unlikely to have an ASD.

Prenatal diagnosis of long QT syndrome: implications for delivery room and neonatal management.

This case describes the prenatal diagnosis and integrated peripartum management of a foetus with 2:1 atrioventricular block and torsade de pointes due to congenital long QT syndrome. The unique issues related to the detection of intrauterine conduction abnormalities and ventricular arrhythmias, along with the immediate postnatal care, have been described as an interesting teaching case with successful outcome.

Status of propranolol for treatment of infantile hemangioma and description of a randomized clinical trial.

OBJECTIVES: Our primary objective was to review the current use of propranolol for treatment of infantile hemangioma (IH), specifically regarding 1) the age at initiation of therapy, 2) the method of initiation, 3) the use of other adjuvant therapy, 4) the duration of therapy and relapse rate, 5) the adverse events, and 6) the outcome. Our secondary objective was to describe a randomized, controlled, single-blinded trial comparing propranolol to prednisolone for treatment of IH. METHODS: Ovid Medline and PubMed searches were completed for the MeSH keywords "propranolol" and "hemangioma." Forty-nine English-language articles were published between June 2008 and September 2010, and 28 of these reported data from a total of 213 patients. Only 6 studies treated more than 10 patients, and these were selected for review in detail (154 patients). RESULTS: The treatment was initiated during infancy in 92.9% of patients (mean, 4.5 months). Sixty-five percent of patients were treated with 2 mg/kg per day, and 25.3% with 3 mg/kg per day. Patients were monitored overnight at initiation of treatment in 3 series (59 patients), for 4 to 6 hours as outpatients in 2 series (62 patients), and initially as inpatients but later as outpatients in 1 series (32 patients). Propranolol was used as sole therapy in about two thirds of patients (103 patients). Treatment was ongoing in 46% of patients at the time of publication. The average treatment duration in the remaining patients was 5.1 months. Rebound growth occurred in 21% of patients after a mean of 4.3 months of therapy. Adverse events occurred in 18.1% of patients and included hypotension in 6, somnolence in 6, wheezing in 4, insomnia, agitation, and/or nightmares in 6, cool hands or night sweats in 2, gastroesophageal reflux in 3, and psoriasis-like rash in 1. All authors reported a favorable outcome with propranolol, but the definition of efficacy was not standardized. CONCLUSIONS: Propranolol is an attractive alternative to other treatments for IH. Despite apparent widespread use of this medication, the data are limited, and prospective studies are lacking for this indication. The relatively high rate of adverse effects supports the need for careful monitoring of patients on this therapy. Fastidious reporting of adverse events and objective evaluation of early and late outcomes are necessary to improve our understanding of the use of propranolol for this indication.

Pacing treatment for dilated cardiomyopathy: optimization of resynchronization pacing in pediatrics.

PURPOSE OF REVIEW: The understanding of the therapeutic effects and complications of pacing in pediatric and congenital-heart disease is evolving. The utility and feasibility of cardiac resynchronization therapy (CRT) are now being critically evaluated. This group of patients is heterogeneous, but many individuals eventually share a common clinical destiny of ventricular dyssynchrony and dilated cardiomyopathy. This review will summarize the most recent germane developments in this rapidly changing field. RECENT FINDINGS: Longer-term data are now available for the pediatric and congenital heart population. Some of the technical aspects of this procedure have been improved, including the use of unique combinations of lead placement including hybrid systems. Innovations in echocardiography provide the clinician with the capability to assess mechanical dyssynchrony indices, as well as cardiac function and electrical dyssynchrony, when considering a pediatric or congenital heart disease patient for CRT. SUMMARY: CRT is becoming a valuable tool in the treatment of ventricular dyssynchrony and dilated cardiomyopathy in pediatric and congenital heart disease patients. Diagnostic advances in electrophysiology and echocardiography have enabled clinicians to more effectively evaluate, treat, and optimize device programming for patients before and after CRT. These modalities also allow more detailed data collection, which may aid in the refinement of indications and impact of CRT in this unique population.

Synergistic inhibition of microbial sulfide production by combinations of the metabolic inhibitor nitrite and biocides.

MICs of six broad-spectrum biocides and two specific metabolic inhibitors and fractional inhibitory concentration indexes (FICIs) for controlling a sulfide-producing consortium were determined. Nitrite was synergistic (FICI<1) with all but one biocide due to its specific inhibition of dissimilatory sulfite reductase. Hence, combining nitrite with biocides allows more efficient and cost-effective control of sulfate-reducing bacteria.

Gene expression analysis of the mechanism of inhibition of Desulfovibrio vulgaris Hildenborough by nitrate-reducing, sulfide-oxidizing bacteria.

Sulfate-reducing bacteria (SRB) are inhibited by nitrate-reducing, sulfide-oxidizing bacteria (NR-SOB) in the presence of nitrate. This inhibition has been attributed either to an increase in redox potential or to production of nitrite by the NR-SOB. Nitrite specifically inhibits the final step in the sulfate reduction pathway. When the NR-SOB Thiomicrospira sp. strain CVO was added to mid-log phase cultures of the SRB Desulfovibrio vulgaris Hildenborough in the presence of nitrate, sulfate reduction was inhibited. Strain CVO reduced nitrate and oxidized sulfide, with transient production of nitrite. Sulfate reduction by D. vulgaris resumed once nitrite was depleted. A DNA macroarray with open reading frames encoding enzymes involved in energy metabolism of D. vulgaris was used to study the effects of NR-SOB on gene expression. Shortly following addition of strain CVO, D. vulgaris genes for cytochrome c nitrite reductase and hybrid cluster proteins Hcp1 and Hcp2 were upregulated. Genes for sulfate reduction enzymes, except those for dissimilatory sulfite reductase, were downregulated. Genes for the membrane-bound electron transferring complexes QmoABC and DsrMKJOP were downregulated and unaffected, respectively, whereas direct addition of nitrite downregulated both operons. Overall the gene expression response of D. vulgaris upon exposure to strain CVO and nitrate resembled that observed upon direct addition of nitrite, indicating that inhibition of SRB is primarily due to nitrite production by NR-SOB.

Physiological and gene expression analysis of inhibition of Desulfovibrio vulgaris hildenborough by nitrite.

A Desulfovibrio vulgaris Hildenborough mutant lacking the nrfA gene for the catalytic subunit of periplasmic cytochrome c nitrite reductase (NrfHA) was constructed. In mid-log phase, growth of the wild type in medium containing lactate and sulfate was inhibited by 10 mM nitrite, whereas 0.6 mM nitrite inhibited the nrfA mutant. Lower concentrations (0.04 mM) inhibited the growth of both mutant and wild-type cells on plates. Macroarray hybridization indicated that nitrite upregulates the nrfHA genes and downregulates genes for sulfate reduction enzymes catalyzing steps preceding the reduction of sulfite to sulfide by dissimilatory sulfite reductase (DsrAB), for two membrane-bound electron transport complexes (qmoABC and dsrMKJOP) and for ATP synthase (atp). DsrAB is known to bind and slowly reduce nitrite. The data support a model in which nitrite inhibits DsrAB (apparent dissociation constant K(m) for nitrite = 0.03 mM), and in which NrfHA (K(m) for nitrite = 1.4 mM) limits nitrite entry by reducing it to ammonia when nitrite concentrations are at millimolar levels. The gene expression data and consideration of relative gene locations suggest that QmoABC and DsrMKJOP donate electrons to adenosine phosphosulfate reductase and DsrAB, respectively. Downregulation of atp genes, as well as the recorded cell death following addition of inhibitory nitrite concentrations, suggests that the proton gradient collapses when electrons are diverted from cytoplasmic sulfate to periplasmic nitrite reduction.

Analysis of environmental microbial communities by reverse sample genome probing.

Development of fast and accurate methods for monitoring environmental microbial diversity is one of the great challenges in microbiology today. Oligonucleotide probes based on 16S rRNA sequences are widely used to identify bacteria in the environment. However, the successful development of a chip of immobilized 16S rRNA probes for identification of large numbers of species in a single hybridization step has not yet been reported. In reverse sample genome probing (RSGP), labelled total community DNA is hybridized to arrays in which genomes of cultured microorganisms are spotted on a solid support in denatured form. This method has provided useful information on changes in composition of the cultured component of microbial communities in oil fields, the soil rhizhosphere, hydrocarbon-contaminated soils and acid mine drainage sites. Applications and limitations of the method, as well as the prospects of extending RSGP to cover also the as yet uncultured component of microbial communities, are evaluated.

Microbial community composition at an ethane pyrolysis plant site at different hydrocarbon inputs.

Aerobic biodegradation of C5+, a contaminant at ethane pyrolysis plants, consisting mainly of benzene, toluene, xylene, styrene, dicyclopentadiene (DCPD) and naphthalene, removes all components except the recalcitrant DCPD. The number (N) of total culturable heterotrophs in contaminated and uncontaminated soil cultures increased up to three orders of magnitude upon incubation with C5+, or with C5+ components other than DCPD. Exposure of soil cultures to C5+ for 2-4 weeks and to DCPD for a further 43-52 weeks caused N to increase 3, then decrease two orders of magnitude. Early microbial communities (up to 13 weeks) were dominated by Pseudomonas spp. and late communities (40-60 weeks) by Alcaligenes spp., especially in contaminated soil cultures. The hydrocarbon used (C5+ or one of its components) was a less important determinant of community composition than incubation time. Rates of aerobic degradation of benzene, toluene and styrene by the soil cultures were greater for the pure components than for the components in the C5+ mixture. The difference was less pronounced for m-xylene. The exception, naphthalene, was degraded more slowly when in pure form. However, the combined rate of all C5+ components in the mixture was similar to the highest rates observed for pure components. We conclude that soil communities efficiently metabolize a C5+ mixture or its pure components and that the community composition is hardly affected by different hydrocarbon inputs. Consequently, determination of the community composition does not provide a good indicator of the hydrocarbons being metabolized.