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Children with CHD and acquired heart disease have unique, high-risk physiology. They may have a higher risk of adverse tracheal-intubation-associated events, as compared with children with non-cardiac disease.
Materials and methods
We sought to evaluate the occurrence of adverse tracheal-intubation-associated events in children with cardiac disease compared to children with non-cardiac disease. A retrospective analysis of tracheal intubations from 38 international paediatric ICUs was performed using the National Emergency Airway Registry for Children (NEAR4KIDS) quality improvement registry. The primary outcome was the occurrence of any tracheal-intubation-associated event. Secondary outcomes included the occurrence of severe tracheal-intubation-associated events, multiple intubation attempts, and oxygen desaturation.
A total of 8851 intubations were reported between July, 2012 and March, 2016. Cardiac patients were younger, more likely to have haemodynamic instability, and less likely to have respiratory failure as an indication. The overall frequency of tracheal-intubation-associated events was not different (cardiac: 17% versus non-cardiac: 16%, p=0.13), nor was the rate of severe tracheal-intubation-associated events (cardiac: 7% versus non-cardiac: 6%, p=0.11). Tracheal-intubation-associated cardiac arrest occurred more often in cardiac patients (2.80 versus 1.28%; p<0.001), even after adjusting for patient and provider differences (adjusted odds ratio 1.79; p=0.03). Multiple intubation attempts occurred less often in cardiac patients (p=0.04), and oxygen desaturations occurred more often, even after excluding patients with cyanotic heart disease.
The overall incidence of adverse tracheal-intubation-associated events in cardiac patients was not different from that in non-cardiac patients. However, the presence of a cardiac diagnosis was associated with a higher occurrence of both tracheal-intubation-associated cardiac arrest and oxygen desaturation.
In 2013, New York State mandated that, during influenza season, unvaccinated healthcare personnel (HCP) wear a surgical mask in areas where patients are typically present. We found that this mandate was associated with increased HCP vaccination and decreased HCP visits to the hospital Workforce Health and Safety Department with respiratory illnesses and laboratory-confirmed influenza.
Hypertension following primary coarctation repair affects up to a third of subjects. A number of studies suggest that future hypertension risk is reduced if primary repair is performed at a younger age.
The objective of this study was to evaluate the risk of future medical treatment for hypertension depending on age of primary coarctation repair.
This study was carried out at a tertiary paediatric cardiology referral centre. Retrospective database evaluation of children aged <16 years undergoing primary surgical coarctation repair between October, 2005 and October, 2014 was carried out. Patients with complex heart diseases were excluded. The following age groups were considered: neonate (⩽28 days), infant (>28 days and ⩽12 months), and children (>12 months). Main outcome measure is the need for long-term anti-hypertensive medication. The risk for re-coarctation was also evaluated.
A total of 87 patients were analysed: 60 neonates, 17 infants, 10 children. Among them, 6.7% neonates, 29.4% infants, and 40% children required long-term anti-hypertensive medications. Group differences were statistically significant (p=0.004). After adjustment for type of repair, the risk of long-term anti-hypertensive therapy was 4.5 (95% confidence interval 1.2–16.9, p=0.025) and 10.5 times (95% confidence interval 2.6–42.3, p=0.001) higher if primary repair was carried out in infancy and childhood, respectively, compared with neonates. Among all, 13 patients developed re-coarctation: 21.7% in the neonatal group, 5.9% in the infant group, and 20% in the child group. We could not demonstrate a significant difference between these proportions or calculate a reliable risk for developing re-coarctation.
Risk of medical treatment for hypertension was lowest when primary repair was carried out during the neonatal period, rising 10-fold if first operated on as a child. Knowing the likelihood of hypertension development depending on age of primary repair is useful for long-term surveillance and counselling.
The objective of this study was to quantify the potential retail pharmacy vaccine administration capacity and its possible impact on pandemic influenza vaccine uptake.
We developed a discrete event simulation model by use of ExtendSim software (Imagine That Inc, San Jose, CA) to forecast the potential effect of retail pharmacy vaccine administration on total weekly vaccine administration and the time needed to reach 80% vaccination coverage with a single dose of vaccine per person.
Results showed that weekly national vaccine administration capacity increased to 25 million doses per week when retail pharmacist vaccination capacity was included in the model. In addition, the time to achieve 80% vaccination coverage nationally was reduced by 7 weeks, assuming high public demand for vaccination. The results for individual states varied considerably, but in 48 states the inclusion of pharmacies improved time to 80% coverage.
Pharmacists can increase the numbers of pandemic influenza vaccine doses administered and reduce the time to achieve 80% single-dose coverage. These results support efforts to ensure pharmacist vaccinators are integrated into pandemic vaccine response planning. (Disaster Med Public Health Preparedness. 2017;11:587–593)
This chapter reviews the sexually dimorphic nature of meiosis in mammalian species, since many aspects of recombination depend on whether the gamete is proceeding through spermatogenesis or oogenesis. Since meiotic recombination occurs at prophase during fetal development in mammalian females, few investigations of human recombination have focused on this stage. Linkage disequilibrium (LD) analysis provides a powerful tool for the generation of high resolution genetic maps. LD mapping does not require analysis of multiple generations in a family. Rather it is a simple assessment of haplotype blocks among different individuals. Fortunately, with improvements in immunostaining techniques and the increasing availability of antibodies capable of detecting meiosis-acting proteins, it has now become possible to analyze the processes of pairing, synapsis, and recombination in human fetal oocytes. Advances in mapping methodology have led to the generation of high-resolution male and female genetic maps.
Recent US disasters highlight the current imbalance between the high proportion of chronically ill Americans who depend on prescription medications and their lack of medication reserves for disaster preparedness. We examined barriers that Los Angeles County residents with chronic illness experience within the prescription drug procurement system to achieve recommended medication reserves.
A mixed methods design included evaluation of insurance pharmacy benefits, focus group interviews with patients, and key informant interviews with physicians, pharmacists, and insurers.
Results and Discussion
Most prescriptions are dispensed as 30-day units through retail pharmacies with refills available after 75% of use, leaving a monthly medication reserve of 7 days. For patients to acquire 14- to 30-day disaster medication reserves, health professionals interviewed supported 60- to 100-day dispensing units. Barriers included restrictive insurance benefits, patients’ resistance to mail order, and higher copay-ments. Physicians, pharmacists, and insurers also varied widely in their preparedness planning and collective mutual-aid plans, and most believed pharmacists had the primary responsibility for patients’ medication continuity during a disaster.
To strengthen prescription drug continuity in disasters, recommendations include the following: (1) creating flexible drug-dispensing policies to help patients build reserves, (2) training professionals to inform patients about disaster planning, and (3) building collaborative partnerships among system stakeholders. (Disaster Med Public Health Preparedness. 2013;7:257-265)
Over the past fifty years the scanning electron microscope (SEM) has established itself as the most versatile and productive tool for imaging and microanalysis in many areas of science and technology, and some seventy-thousand instruments generate millions of micrographs every day. Scanning electron microscopes do, however, have one fundamental limitation in that the only experimental variable available to the operator is the choice of the accelerating voltage. Although the ability to vary beam energy is both necessary and important, it is an unfortunate fact that changing the beam energy also alters many aspects of performance: imaging resolution, relative strength of different signal components, depth of beam penetration, capabilities of the various analytical systems, and the severity of charging and beam-induced damage. This makes it difficult or impossible to optimize the interaction of interest.
Because the ability to perform some form of chemical microanalysis has become an essential feature for any microscope, it is necessary to investigate what options are available in the new “ORION” helium ion microscope (HIM). The HIM has the ability to visualize local variations in specimen chemistry in both the ion induced secondary electron and the Rutherford backscattered imaging modes, but this provides only limited and qualitative information. Quantitative, elementally specific, microanalysis could be performed in the HIM using secondary electron spectroscopy, Rutherford backscattered ion spectroscopy, or secondary ion mass spectroscopy, but while each of these options has promise, none of them can presently guarantee either reliable element identification or quantitative analysis across the periodic table.
In many semiconductor materials problems, structural characterizations must be achieved in both the lateral and vertical dimensions. Although a combination of cross-sectional and planar transmission electron microscopy can provide this information, the sample preparation time is demanding and only relatively small volumes of material are examined. We describe here an alternative approach in which the charge collection (‘CCM’) imaging mode of the scanning electron microscope (SEM) is used. It is shown that, by varying the incident electron beam energy, electricallly active defects at different positions beneath the entrance surface of the material can be imaged and their depth estimated.
In this paper we will present recent experimental results, using electron holography and electron interferometry, of studies of ferroelectric domain walls in BaTiO3 thin films. Unlike conventional TEM diffraction contrast imaging of ferroelectrics, the new technique that we have developed not only allows direct visualization of ferroelectric domain walls and electrostatic field distributions in the vicinity of the domain wall, but also enables quantitative measurement of domain wall width and local polarization. We have measured 90° domain wall width to be between 20 to 50 Å for a BaTiO3 thin specimen. The variation of polarization across the domain wall will be shown to be close to that predicted by the Zhirnov model. The value of the measured spontaneous polarization is about 1.5×10−5 C/cm2, which is closed to the bulk macroscopically measured value.
The scanning electron microscope (SEM) is the most widely used, as well as the most versatile, of electron-optical instruments. In all of the imaging modes of the instrument it is now possible to achieve a spatial resolution on the nanometer scale from a bulk specimen, provided that the electron-optical performance of the instrument is of the necessary quality. In practice this means that a field emission gun (FEG) as well as a highly excited probe forming lens must be used. With state-of-the-art instrumentation, image resolutions as good as 4 - 5 nm at lkeV, and lnm at 20keV, are now achievable. This paper outlines the design criteria for a high resolution FEG SEM and discusses the type of image information available. The performance achieved is compared to that of other types of microscope that offer similar capabilities.
The theory of imaging crystallographic defects in solid specimens through the use of electron channeling contrast is reviewed and the necessary conditions for observation are deduced. It is shown that current high performance field emission scanning electron microscopes can meet these requirements and produce dislocation images from suitable materials.