OBJECTIVE--To assess the effectiveness and safety of amiodarone in the treatment of junctional ectopic tachycardia (JET) after open heart surgery in children. PATIENTS--Between January 1990 and ...December 1991, 16 consecutive patients aged 6 days to 14 years with JET associated with significant haemodynamic impairment after cardiopulmonary bypass were treated with amiodarone as the principal antiarrhythmic drug. INTERVENTIONS--Amiodarone 5 mg/kg was administered intravenously over one hour and the same dose was subsequently infused over 12 hours. This was reviewed every 12 hours and repeated as necessary until a satisfactory heart rate and stable haemodynamics were achieved. Atrial pacing was used whenever possible to provide atrioventricular synchrony. RESULTS--Except for one patient with a JET rate of 160/min, the maximum JET rate ranged from 180/min to 245/min with a mean(SD) of 200 (20)/min. After amiodarone, the heart rates reduced to a mean(SD) of 170 (20), 164 (27), 158 (27), 157 (24), and 153 (19)/min at two, four, eight, 12, and 24 hours respectively. A reduction in tachycardia rate allowing atrial pacing was achieved in 10 patients by two hours. Haemodynamic variables improved in most patients with an increase in mean systolic blood pressure by an average of 15 mm Hg and a decrease in atrial filling pressures by an average of 3.5 mm Hg at four hours after amiodarone administration. There were three deaths: one was a moribund patient who died soon after the onset of JET and the other two deaths were not directly related to JET. COMPLICATIONS--Late bradycardia with hypotension was recorded in one patient. Asymptomatic late sinus bradycardia was seen in several others. CONCLUSIONS--Amiodarone can be used safely and effectively to control JET with haemodynamic improvement in most patients. The addition of atrial pacing confers the advantage of atrioventricular synchrony.
The MiniBooNE experiment will unambiguously confirm or refute the existence of the neutrino oscillation signal seen by the liquid scintillator neutrino detector (LSND) experiment at Los Alamos ...National Laboratory. MiniBooNE will search for the appearance of electron neutrinos in a beam of muon neutrinos. The MiniBooNE detector is a 12-m-diameter sphere filled with mineral oil and instrumented with photomultiplier tubes. The properties of the mineral oil chosen to fill this Cerenkov detector will be important to the experiment. The production of scintillation light in the oil, the attenuation of light across the detector, and the index of refraction of the oil are all important properties that must be known in order to properly model the detector. Fluorescence of the oil, optical dispersion, and oil density are also important quantities. The fluorescence spectra for several pure mineral oils as well as mineral oils doped with a small amount of various fluors were measured to determine the expected scintillation spectra from those oils. Index of refraction measurements were made in order to determine the Cerenkov angle and the dispersion for each oil. Attenuation tests were performed to rind an oil with maximal attenuation length and with no abnormal absorption features. This paper presents measurements of some of the oil properties, which are made at Fermilab using several experimental setups. Based on the results of these tests (and a price within budget constraints), Marcol 7 oil was selected for the MiniBooNE experiment.
Resistant Kawasaki disease Nachiappan, J; May, M; Hawker, RE ...
Journal of paediatrics and child health,
September 2004, 2004 Sep-Oct, 2004-09-00, 20040901, Letnik:
40, Številka:
9‐10
Journal Article
The recent discoveries in the neutrino sector in the Standard Model have opened a new frontier in high-energy physics. Understanding neutrinos and how they interact is crucial to continuing to verify ...the Standard Model and look beyond Standard Model physics. The MiniBooNE experiment is a /spl nu/~/sub /spl mu// /spl rarr/ /spl nu/~/sub e/ oscillation search designed to confirm or rule out the neutrino oscillation signal seen by the LSND experiment at the Los Alamos National Laboratory. The MiniBooNE detector, a sphere filled with mineral oil and lined with 8-in Hamamatsu photomultiplier tubes (PMTs), uses Cerenkov imaging to identify /spl nu//sub /spl mu// and /spl nu//sub e/ interactions. The PMTs are the main detector component and must be well understood. They underwent a series of tests to determine their functionality and figures of merit in order to be placed in the detector, as described here.
The MiniBooNE neutrino detector at Fermilab (FNAL) is filled with 250,000 gallons of pure mineral oil. The principal signal for MiniBooNE is light observed in a prompt Cherenkov cone. Scattering and ...fluorescence modify our detection of this light. Scintillation is also created by ionization in the oil. Studies of fluorescence of this oil have been carried out over a wide spectrum of excited light and time resolved fluorescence with a narrower range of excitation. Polarized scattering measurements have been carried out at longer wavelengths. Time resolved and spectrally resolved scintillation has been studied with a 200 MeV proton beam at the Indiana University Cyclotron Facility. Results of these studies will be reported.
A 3-year-old girl presented with a febrile illness complicated by right ventricular outflow tract tachycardia, which persisted after resolution of the presumed viral infection. The tachycardia was ...intermittent, but was significantly exacerbated by exercise. Radiofrequency ablation (RFA) of the ectopic focus was successfully performed and the child remains free of tachycardia 12 months later. A review of the literature suggests that RFA in children is increasingly seen as a safe and convenient option for the treatment of supraventricular tachycardia, whereas the management of ectopic ventricular tachycardia in pediatric practice has not been well defined.
A 4-kg male child, born at 34 weeks to a gestational diabetic mother, had a large ductus arteriosus aneurysm causing phrenic and recurrent laryngeal nerve palsies and large airway compression. The ...right and left atrial appendages and distal descending aorta were cannulated, allowing left heart partial or complete cardiopulmonary bypass as necessary. On bypass the ductus was ligated, decompressed, and oversewn but not excised. Examination 1 month later suggested resolution of the recurrent laryngeal palsy and echocardiography showed regression of the aneurysm. Ductus ligation and decompression was an effective surgical treatment, which is less likely to cause complications than resection.
To test the reproducibility and thermostability of a new format of the Card-Agglutination Test for Trypanosomiasis (CATT) test for Human African Trypanosomiasis (HAT), designed for use at primary ...health care facility level in endemic countries. A population of 4217 from highly endemic villages was screened using the existing format of the CATT test (CATT-R250) on whole blood. All those testing positive (220) and a random sample of negatives (555) were retested in the field with the new format (CATT-D10). Inter-format reproducibility was assessed by calculating kappa. All samples testing positive on whole blood with either method were further evaluated in Belgium by CATT titration of serum by two observers, using both old and new format. CATT-D10 test kits were incubated under four temperature regimens (4, 37, 45 °C and fluctuating) with regular assessments of reactivity over 18 months. Inter-format reproducibility of CATT-D10 vs. CATT-R250 on whole blood performed by laboratory technicians in the field was excellent with kappa values of 0.83-0.89. Both inter- and intra-format reproducibility assessed by CATT titration were excellent, with 96.5-100% of all differences observed falling within the limits of ±1 titration step. After 18 months, reactivity of test kits incubated under all four temperature regimens was still well above the minimum threshold considered acceptable. The CATT-D10 is thermostable and can be used interchangeably with the old format of the CATT test. It is highly suitable for use in peripheral health facilities in HAT-endemic countries.
The sidereal time dependence of MiniBooNE ν e and ν ¯ e appearance data is analyzed to search for evidence of Lorentz and CPT violation. An unbinned Kolmogorov–Smirnov (K–S) test shows both the ν e ...and ν ¯ e appearance data are compatible with the null sidereal variation hypothesis to more than 5%. Using an unbinned likelihood fit with a Lorentz-violating oscillation model derived from the Standard Model Extension (SME) to describe any excess events over background, we find that the ν e appearance data prefer a sidereal time-independent solution, and the ν ¯ e appearance data slightly prefer a sidereal time-dependent solution. Limits of order 10 - 20 GeV are placed on combinations of SME coefficients. These limits give the best limits on certain SME coefficients for ν μ → ν e and ν ¯ μ → ν ¯ e oscillations. The fit values and limits of combinations of SME coefficients are provided.
"Grown-ups" with congenital heart disease Celermajer, D S; Pressley, L; Robinson, P J ...
Medical journal of Australia,
06/1996, Letnik:
164, Številka:
12
Journal Article
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