An in situ trap capacitance measurement and ion-trapping detection scheme for a Penning ion trap facility.

This paper presents the design and implementation of an in situ measurement setup for the capacitance of a five electrode Penning ion trap (PIT) facility at room temperature. For implementing a high Q resonant circuit for the detection of trapped electrons/ions in a PIT, the value of the capacitance of the trap assembly is of prime importance. A tunable Colpitts oscillator followed by a unity gain buffer and a low pass filter is designed and successfully implemented for a two-fold purpose: in situ measurement of the trap capacitance when the electric and magnetic fields are turned off and also providing RF power at the desired frequency to the PIT for exciting the trapped ions and subsequent detection. The setup is tested for the in situ measurement of trap capacitance at room temperature and the results are found to comply with those obtained from measurements using a high Q parallel resonant circuit setup driven by a standard RF signal generator. The Colpitts oscillator is also tested successfully for supplying RF power to the high Q resonant circuit, which is required for the detection of trapped electrons/ions.

Lean intervention improves patient discharge times, improves emergency department throughput and reduces congestion.

OBJECTIVE: To determine if a lean intervention improved emergency department (ED) throughput and reduced ED boarding by improving patient discharge efficiency from a tertiary care children's hospital. METHODS: The study was conducted at a tertiary care children's hospital to study the impact lean that changes made to an inpatient pediatric service line had on ED efficiency. Discharge times from the general pediatrics' service were compared to patients discharged from all other pediatric subspecialty services. The intervention was multifaceted. First, team staffing reconfiguration permitted all discharge work to be done at the patient's bedside using a new discharge checklist. The intervention also incorporated an afternoon interdisciplinary huddle to work on the following day's discharges. Retrospectively, we determined the impact this had on median times of discharge order entry, patient discharge, and percent of patients discharged before noon. As a marker of ED throughput, we determined median hour of day that admitted patients left the ED to move to their hospital bed. As marker of ED congestion we determined median boarding times. RESULTS: For the general pediatrics service line, the median discharge order entry time decreased from 1:43pm to 11:28am (p < 0.0001) and the median time of discharge decreased from 3:25pm to 2:25pm (p < 0.0001). The percent of patients discharged before noon increased from 14.0% to 26.0% (p < 0.0001). The discharge metrics remained unchanged for the pediatric subspecialty services group. Median ED boarding time decreased by 49 minutes (p < 0.0001). As a result, the median time of day admitted patients were discharged from the ED was advanced from 5 PM to 4 PM. CONCLUSION: Lean principles implemented by one hospital service line improved patient discharge times enhanced patient ED throughput, and reduced ED boarding times.

Addison's disease.

Addison's disease is a rare endocrinal disorder, with several oral and systemic manifestations. A variety of pathological processes may cause Addison's disease. Classically, hyperpigmentation is associated with the disease, and intraoral pigmentation is perceived as the initial sign and develops earlier than the dermatological pigmentation. The symptoms of the disease usually progress slowly and an event of illness or accident can make the condition worse and may lead to a life-threatening crisis. In this case, several oral as well as systemic manifestation of the Addison's disease was encountered.

Effect of antibiotic pretreatment on cerebrospinal fluid profiles of children with bacterial meningitis.

OBJECTIVE: The goal of this study was to evaluate the effect of antibiotic administration before lumbar puncture on cerebrospinal fluid profiles in children with bacterial meningitis. METHODS: We reviewed the medical records of all children (1 month to 18 years of age) with bacterial meningitis who presented to 20 pediatric emergency departments between 2001 and 2004. Bacterial meningitis was defined by positive cerebrospinal fluid culture results for a bacterial pathogen or cerebrospinal fluid pleocytosis with positive blood culture and/or cerebrospinal fluid latex agglutination results. Probable bacterial meningitis was defined as positive cerebrospinal fluid Gram stain results with negative results of bacterial cultures of blood and cerebrospinal fluid. Antibiotic pretreatment was defined as any antibiotic administered within 72 hours before the lumbar puncture. RESULTS: We identified 231 patients with bacterial meningitis and another 14 with probable bacterial meningitis. Of those 245 patients, 85 (35%) had received antibiotic pretreatment. After adjustment for patient age, duration and severity of illness at presentation, and bacterial pathogen, longer duration of antibiotic pretreatment was not significantly associated with cerebrospinal fluid white blood cell count, cerebrospinal fluid absolute neutrophil count. However, antibiotic pretreatment was significantly associated with higher cerebrospinal fluid glucose and lower cerebrospinal fluid protein levels. Although these effects became apparent earlier, patients with >or=12 hours of pretreatment, compared with patients who either were not pretreated or were pretreated for <12 hours, had significantly higher median cerebrospinal fluid glucose levels (48 mg/dL vs 29 mg/dL) and lower median cerebrospinal fluid protein levels (121 vs 178 mg/dL). CONCLUSIONS: In patients with bacterial meningitis, antibiotic pretreatment is associated with higher cerebrospinal fluid glucose levels and lower cerebrospinal fluid protein levels, although pretreatment does not modify cerebrospinal fluid white blood cell count or absolute neutrophil count results.

B-type natriuretic peptide in the emergency diagnosis of critical heart disease in children.

OBJECTIVE: The initial presentation of congenital and acquired heart disease in children can present a diagnostic challenge. We sought to evaluate B-type natriuretic peptide as a marker of critical heart disease in children at presentation in the acute care setting. METHODS: A cohort of 33 pediatric patients with newly diagnosed congenital or acquired heart disease had B-type natriuretic peptide levels obtained on hospital admission after evaluation in an acute care setting. Patients were admitted from March 2005 through February 2007. A noncardiac cohort of 70 pediatric patients who presented with respiratory or infectious complaints had B-type natriuretic peptide levels obtained during emergency department evaluation. A comparison of B-type natriuretic peptide results was performed. RESULTS: Cardiac diagnoses included cardiomyopathy (14), left-sided obstructive lesions (12), anomalous left coronary artery from the pulmonary artery (4), total anomalous pulmonary venous return (2), and patent ductus arteriosus (1). Cardiac cohort mean age at presentation was 33.6 months. The 33 patients with new cardiac diagnoses had a mean B-type natriuretic peptide level of 3290 pg/mL (SD: +/-1609; range: 521 to >5000 pg/mL). The 70 noncardiac patients' mean age at presentation was 23.1 month, and mean B-type natriuretic peptide level was 17.4 pg/mL (SD: +/-20; range: <5 to 174 pg/mL). CONCLUSIONS: B-type natriuretic peptide levels were markedly elevated at presentation in the acute care setting for all patients in this cohort of children with newly diagnosed congenital or acquired heart disease. B-type natriuretic peptide levels from noncardiac patients were significantly lower, with no overlap to the cardiac disease group. B-type natriuretic peptide level can be useful as a diagnostic marker to aid in the recognition of pediatric critical heart disease in the acute care setting.

Clinical prediction rule for identifying children with cerebrospinal fluid pleocytosis at very low risk of bacterial meningitis.

CONTEXT: Children with cerebrospinal fluid (CSF) pleocytosis are routinely admitted to the hospital and treated with parenteral antibiotics, although few have bacterial meningitis. We previously developed a clinical prediction rule, the Bacterial Meningitis Score, that classifies patients at very low risk of bacterial meningitis if they lack all of the following criteria: positive CSF Gram stain, CSF absolute neutrophil count (ANC) of at least 1000 cells/microL, CSF protein of at least 80 mg/dL, peripheral blood ANC of at least 10,000 cells/microL, and a history of seizure before or at the time of presentation. OBJECTIVE: To validate the Bacterial Meningitis Score in the era of widespread pneumococcal conjugate vaccination. DESIGN, SETTING, AND PATIENTS: A multicenter, retrospective cohort study conducted in emergency departments of 20 US academic medical centers through the Pediatric Emergency Medicine Collaborative Research Committee of the American Academy of Pediatrics. All children aged 29 days to 19 years who presented at participating emergency departments between January 1, 2001, and June 30, 2004, with CSF pleocytosis (CSF white blood cells > or =10 cells/microL) and who had not received antibiotic treatment before lumbar puncture. MAIN OUTCOME MEASURE: The sensitivity and negative predictive value of the Bacterial Meningitis Score. RESULTS: Among 3295 patients with CSF pleocytosis, 121 (3.7%; 95% confidence interval [CI], 3.1%-4.4%) had bacterial meningitis and 3174 (96.3%; 95% CI, 95.5%-96.9%) had aseptic meningitis. Of the 1714 patients categorized as very low risk for bacterial meningitis by the Bacterial Meningitis Score, only 2 had bacterial meningitis (sensitivity, 98.3%; 95% CI, 94.2%-99.8%; negative predictive value, 99.9%; 95% CI, 99.6%-100%), and both were younger than 2 months old. A total of 2518 patients (80%) with aseptic meningitis were hospitalized. CONCLUSIONS: This large multicenter study validates the Bacterial Meningitis Score prediction rule in the era of conjugate pneumococcal vaccine as an accurate decision support tool. The risk of bacterial meningitis is very low (0.1%) in patients with none of the criteria. The Bacterial Meningitis Score may be helpful to guide clinical decision making for the management of children presenting to emergency departments with CSF pleocytosis.

Pediatric head trauma: changes in use of computed tomography in emergency departments in the United States over time.

STUDY OBJECTIVE: Head trauma is common in children. In the absence of evidence-based recommendations, variations exist in the initial emergency department (ED) evaluation and treatment of children with head trauma. We sought to describe the use of computed tomography (CT) over time in the treatment of children with acute closed head trauma in US EDs. METHODS: This was a cross-sectional analysis of data from the National Hospital Ambulatory Care Survey database from 1995 to 2003. We identified patients aged 0 to 18 years, with head trauma by chief complaint or discharge diagnosis. We collected the following data: chief complaint, patient demographics, patient disposition, discharge diagnosis, and use of CT. Frequency and characteristics of the use of CT scan for evaluation of children with head trauma. We used descriptive statistics with appropriate weighting to account for the survey methodology. We determined the frequency and the characteristics of the use of CT scans for evaluation of children with head trauma. We used descriptive statistics with appropriate weighting to account for the survey methodology. RESULTS: We identified 2,747 patient encounters, representing 10,536,717 pediatric head trauma visits during the 9-year period. The use of CT increased from 12.8% to 22.4% from 1995 to 2003, with a peak of 28.6% in 2000. CT was used more frequently in the older age groups: 13% (<1 year), 11% (1 to 4 years), 20% (5 to 9 years), and 32% (10 to 18 years). CT was also used more frequently in general EDs (22%) than in pediatric-specific EDs (13%). There were no differences in CT use between teaching and nonteaching facilities (21% in each). Overall, 6.4% of children were either admitted to the hospital or transferred, and this rate remained stable over time. CONCLUSION: The use of CT has increased substantially in the evaluation of children with head trauma from 1995 to 2003. Further study is needed to identify objective criteria for cranial CT in head-injured children and to evaluate the impact of increased CT use on patient outcomes.

Serum neuron-specific enolase as a predictor of short-term outcome in children with closed traumatic brain injury.

BACKGROUND: Closed traumatic brain injury (cTBI) is a significant cause of mortality and morbidity in children. The natural course and extent of recovery from cTBI in children are poorly understood. Neuron-specific enolase (NSE), an enzyme detected in serum following structural damage of neuronal brain cells, appears to be a good marker for intracranial injury. However, to the best of the authors' knowledge, the usefulness of NSE as a predictor of disability in children with cTBI has not been reported. OBJECTIVES: To examine the association between posttraumatic serum NSE level and short-term physical disability in children with cTBI. METHODS: This was a retrospective analysis of a prospectively enrolled cohort of children aged 0-18 years with isolated cTBI presenting to the emergency department (ED) within 24 hours of injury, and having a cranial computed tomography (CT) scan as part of the evaluation. The NSE level was obtained at the time of ED evaluation. Physical disability was measured using the Glasgow Outcome Scale (GOS). The GOS score was assigned retrospectively for enrolled patients by a single investigator blinded to NSE level. Patient outcomes were categorized as good (GOS = 5) or poor (GOS < 5). A single radiologist reviewed all cranial CT scans. RESULTS: Ninety eligible subjects with NSE levels were identified; 86 met the enrollment criteria. Seven subjects (8%) had poor outcome. There was a significant difference in NSE levels between the poor and good outcome groups, even within high-risk subgroups. The area under the curve (AUC) for NSE prediction of poor vs. good outcome was 0.83. A serum NSE level of 21.2 ng/dL was 86% sensitive and 74% specific in predicting poor outcome. CONCLUSIONS: It appears that the serum NSE level can be used as a predictor of global short-term physical disability in children following cTBI.

Risk of serious bacterial infection in children with fever without a source in the post-Haemophilus influenzae era when antibiotics are reserved for culture-proven bacteremia.

OBJECTIVE: To determine the rate of serious bacterial infection in children aged 2 to 36 months with fever without a source in the post-Haemophilus influenzae era, when antibiotic therapy is reserved until blood culture results turn positive. DESIGN AND SETTING: Retrospective review of emergency department, urgent care center, and hospital medical records from an urban children's hospital. PARTICIPANTS: Eligible participants were identified from hospital medical record and microbiology laboratory databases. Immunocompetent individuals aged 2 to 36 months with fever without a source were eligible for enrollment. Exclusion criteria were temperature less than 39.0 degrees C, identifiable focus of infection, current or recent antibiotic use, and hospital admission. INTERVENTIONS AND OUTCOME MEASURES: Enrolled participants were assigned to group 1 (blood culture obtained) or group 2 (no blood culture) and did not receive empiric antibiotic treatment in the emergency department, in the urgent care center, or for home use. Demographic and outcome data were collected on all enrolled patients. RESULTS: During the study, 9241 febrile children were identified; 2641 (29%) met the enrollment criteria. Blood cultures (group 1) were performed on 1202 patients (46%), and 37 (3%) had culture-proven occult bacteremia (95% confidence interval, 2.2%-4.2%). Streptococcus pneumoniae was the most prevalent organism (84%). The mean +/- SD time for reporting a positive blood culture finding was 17.5 +/- 8.5 hours. Two patients (0.08%; 95% confidence interval, 0.009%-0.27%) developed serious bacterial infection, and both recovered completely. CONCLUSION: Reserving antibiotic therapy for culture-proven occult bacteremia was not associated with increased risk of developing serious bacterial infection compared with previously published data.