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Paediatric cardiac surgery on cardiopulmonary bypass induces substantial physiologic changes that contribute to post-operative morbidity and mortality. Fluid overload and oedema are prevalent complications, routinely treated with diuretics. The optimal diuretic choice, timing of initiation, dose, and interval remain largely unknown.
To guide clinical practice and future studies, we used PubMed and EMBASE to systematically review the existing literature of clinical trials involving diuretics following cardiac surgery from 2000 to 2020 in children aged 0–18 years. Studies were assessed by two reviewers to ensure that they met eligibility criteria.
We identified nine studies of 430 children across four medication classes. Five studies were retrospective, and four were prospective, two of which included randomisation. All were single centre. There were five primary endpoints – urine output, acute kidney injury, fluid balance, change in serum bicarbonate level, and required dose of diuretic. Included studies showed early post-operative diuretic resistance, suggesting higher initial doses. Two studies of ethacrynic acid showed increased urine output and lower diuretic requirement compared to furosemide. Children receiving peritoneal dialysis were less likely to develop fluid overload than those receiving furosemide. Chlorothiazide, acetazolamide, and tolvaptan demonstrated potential benefit as adjuncts to traditional diuretic regimens.
Early diuretic resistance is seen in children following cardiopulmonary bypass. Ethacrynic acid appears superior to furosemide. Adjunct diuretic therapies may provide additional benefit. Study populations were heterogeneous and endpoints varied. Standardised, validated endpoints and pragmatic trial designs may allow investigators to determine the optimal diuretic, timing of initiation, dose, and interval to improve post-operative outcomes.
Infants with moderate-to-severe CHD frequently undergo cardiopulmonary bypass surgery in childhood. Morbidity and mortality are highest in those who develop post-operative low cardiac output syndrome. Vasoactive and inotropic medications are mainstays of treatment for these children, despite limited evidence supporting their use.
To help inform clinical practice, as well as the conduct of future trials, we performed a systematic review of existing literature on inotropes and vasoactives in children after cardiac surgery using the PubMed and EMBASE databases. We included studies from 2000 to 2020, and the patient population was defined as birth – 18 years of age. Two reviewers independently reviewed studies to determine final eligibility.
The final analysis included 37 papers. Collectively, selected studies reported on 12 different vasoactive and inotropic medications in 2856 children. Overall evidence supporting the use of these drugs in children after cardiopulmonary bypass was limited. The majority of studies were small with 30/37 (81%) enrolling less than 100 patients, 29/37 (78%) were not randomised, and safety and efficacy endpoints differed widely, limiting the ability to combine data for meta-analyses.
Vasoactive and inotropic support remain critical parts of post-operative care for children after cardiopulmonary bypass surgery. There is a paucity of data for the selection and dosing of vasoactives and inotropes for these patients. Despite the knowledge gaps that remain, numerous recent innovations create opportunities to rethink the conduct of clinical trials in this high-risk population.
Modafinil was tested for efficacy in facilitating abstinence in cocaine-dependent patients, compared to placebo.
This is a double-blind placebo-controlled study, with 12 weeks of treatment and a 4-week follow-up. 210 treatment-seekers with DSM-IV diagnosis of cocaine dependence consented and enrolled. 72 participants were randomized to placebo, 69 to modafinil 200mg, and 69 to modafinil 400mg, taken once daily on awakening. Participants attended the clinic three times per week for assessments and urine drug screens, and had one hour of individual psychotherapy once per week. The primary outcome was the increase in weekly percentage of non-use days. Secondary outcomes included: decrease in the weekly median log of urine benzoylecgonine, subgroup analyses of balancing factors and co-morbid conditions, self-report of alcohol use, addiction severity, craving, and risk behaviors for HIV.
125 participants completed 12 weeks of treatment (60%). The GEE regression analysis showed that for the total sample, the difference between modafinil groups and placebo in the weekly percentage of cocaine non-use days over the 12-week treatment period was not statistically significant (p=0.95). A post-hoc analysis showed a significant effect for modafinil, only in the subgroup of cocaine patients without alcohol dependence. Modafinil 200mg also showed significant effects of an increase in the total number of consecutive non-use days for cocaine (p=0.02), and a reduction in craving (p=0.04).
These data suggest that modafinil, in combination with individual behavioral therapy, was effective for increasing cocaine non-use days in participants without co-morbid alcohol dependence, and in reducing craving.
Introduction: Identification of latent safety threats (LSTs) in the emergency department is an important aspect of quality improvement that can lead to improved patient care. In situ simulation (ISS) takes place in the real clinical environment and multidisciplinary teams can participate in diverse high acuity scenarios to identify LSTs. The purpose of this study is to examine the influence that the profession of the participant (i.e. physician, registered nurse, or respiratory therapist) has on the identification of LSTs during ISS. Methods: Six resuscitation- based adult and pediatric simulated scenarios were developed and delivered to multidisciplinary teams in the Kingston General Hospital ED. Each ISS session consisted of a 10- minute scenario, followed by 3-minutes of individual survey completion and a 7- minute group debrief led by ISS facilitators. An objective assessor recorded LSTs identified during each debrief. Surveys were completed prior to debrief to reduce response bias. Data was collected on participant demographics and perceived LSTs classified in the following categories: medication; equipment; resources and staffing; teamwork and communication; or other. Two reviewers evaluated survey responses and debrief notes to formulate a list of unique LSTs across scenarios and professions. The overall number and type of LSTs from surveys was identified and stratified by health care provider. Results: Thirteen ISS sessions were conducted with a total of 59 participants. Thirty- four unique LSTs (8 medication, 15 equipment, 5 resource, 4 communication, and 2 miscellaneous issues) were identified from surveys and debrief notes. Overall, MDs (n = 12) reported 19 LSTss (n = 41) reported 77 LSTs, and RTs (n = 6) reported 4 LSTs based on individual survey data. The most commonly identified category of LSTs reported by MDs (36.8%) and RTs (75%) was equipment issues while RNs most commonly identified medication issues (36.4%). Participants with □5 years of experience in their profession, on average identified more LSTs in surveys than participants with >5 years experience (1.9 LSTs vs 1.5 LSTs respectively). Conclusion: Nursing staff identified the highest number of LSTs across all categories. There was fairly unanimous identification of major LSTs across professions, however each profession did identify unique perspectives on LSTs in survey responses. ISS programs with the purpose of LST identification would benefit from multidisciplinary participation.
Family-based strategies to reduce the risk of overweight in childhood are needed in the Caribbean.
To investigate the associations between parental characteristics and risk of overweight and explore possible mechanisms.
Data from a parenting intervention were analysed. Parental characteristics were obtained by questionnaire at enrolment. At 18 months, 501 infants (82.9% of cohort) had weight and length measured using standardized methods. The association of parents’ characteristics with risk of infant overweight was assessed using random-effects logistic regression. Four focus groups among mothers in Jamaica were conducted to explore mechanisms.
Overall, 20.6% of infants were ‘at risk of overweight’. Fathers were present in 52% of households. Fathers’ presence [OR (95% CI) 0.60 (0.37–0.96)] was associated with reduced risk of overweight independent of socioeconomic status. Mothers reported that fathers encouraged healthier practices.
Fathers may be important agents of change in intervention strategies to prevent childhood overweight.
In sub-Saharan Africa, there are limited data on burden of non-alcohol substance abuse (NAS) and depressive symptoms (DS), yet potential risk factors such as alcohol and intimate partner violence (IPV) are common and NAS abuse may be the rise. The aim of this study was to measure the burden of DS and NAS abuse, and determine whether alcohol use and IPV are associated with DS and/or NAS abuse. We conducted a cross-sectional study at five sites in four countries: Nigeria (nurses), South Africa (teachers), Tanzania (teachers) and two sites in Uganda (rural and peri-urban residents). Participants were selected by simple random sampling from a sampling frame at each of the study sites. We used a standardized tool to collect data on demographics, alcohol use and NAS use, IPV and DS and calculated prevalence ratios (PR). We enrolled 1415 respondents and of these 34.6% were male. DS occurred among 383 (32.3%) and NAS use among 52 (4.3%). In the multivariable analysis, being female (PR = 1.49, p = 0.008), NAS abuse (PR = 2.06, p = 0.02) and IPV (PR = 2.93, p < 0.001) were significantly associated with DS. Older age [odds ratio (OR) = 0.31, p < 0.001)], female (OR = 0.48, p = 0.036) were protective of NAS but current smokers (OR = 2.98, p < 0.001) and those reporting IPV (OR = 2.16, p = 0.024) were more likely to use NAS. Longitudinal studies should be done to establish temporal relationships with these risk factors to provide basis for interventions.
We examined risk factors associated with the intestinal acquisition of antimicrobial-resistant extraintestinal pathogenic Escherichia coli (ExPEC) and development of community-acquired urinary tract infection (UTI) in a case-control study of young women across Canada. A total of 399 women were recruited; 164 women had a UTI caused by E. coli resistant to ⩾1 antimicrobial classes and 98 had a UTI caused by E. coli resistant to ⩾3 antimicrobial classes. After adjustment for age, student health service (region of Canada) and either prior antibiotic use or UTI history, consumption of processed or ground chicken, cooked or raw shellfish, street foods and any organic fruit; as well as, contact with chickens, dogs and pet treats; and travel to Asia, were associated with an increased risk of UTI caused by antimicrobial resistant E. coli. A decreased risk of antimicrobial resistant UTI was associated with consumption of apples, nectarines, peppers, fresh herbs, peanuts and cooked beef. Drug-resistant UTI linked to foodborne and environmental exposures may be a significant public health concern and understanding the risk factors for intestinal acquisition of existing or newly emerging lineages of drug-resistant ExPEC is important for epidemiology, antimicrobial stewardship and prevention efforts.
Since the discovery of periodic variability of Class II methanol masers associated with high-mass star formation, several possible driving mechanisms have been proposed to explain this phenomenon. Here the colliding wind binary (CWB) hypothesis is proposed to describe the periodic variability. It is shown that the recombination of a partially ionized gas describes the flare profiles remarkably well. In addition, the quiescent state flux density is also described remarkably well by the time-dependent change of the electron density. This suggests that the periodicity is caused by the time-dependent change in the radio free-free emission from the background HII regions against which the maser is projected.
We introduce the newly developed database of circumstellar maser sources. Until now, the compilations comprehensively including the three major maser species in evolved stars (i.e., SiO, H2O, OH) has been practically limited only to the Benson’s catalog (Benson et al. 1990), which was published more than a quarter of a century ago. For OH masers alone, there exists the University of Hamburg (UH) database, but there is no updated compilation work for H2O and SiO masers. In order to utilize the information of masers in actual studies, it is highly desirable to have a database containing all the three masers. We are currently constructing a database covering SiO, H2O and OH masers. This database consists of a web-service, which accesses compiled maser observations in available archives and combines them with the data we newly collected and IR databases. The archives currently used are the OH maser archive from Engels & Bunzel (2015), and H2O and SiO archives, which are currently under construction. So far, the information of about 27,000 observations (about 10,000 objects) has been implemented. We also have a plan to extend the database by including higher transitions and other types of objects, such as young stellar objects, in future. In this paper, we briefly summarize, (1) outline of the data collected, and (2) future development plans of the eDAMS system. The URL of the database is as follows: http://maserdb.ins.urfu.ru/
The first periodic Class II methanol maser was reported on in 2003. Since that time, a number of different monitoring programmes have found periodic masers, as well as other modes of variability. In a few cases, periodicity has been found in other maser species such as formaldehyde and water. Several distinct characteristics of light curves have been noted, possibly pointing to different underlying mechanisms for periodicity if one assumes a linear response to incoming radiation. I will give a brief overview of the known periodic sources, discuss current theories, and present new results obtained from monitoring mainline hydroxyl masers using the seven-element Karoo Array Telescope (KAT-7) during its science verification phase.
The Central Molecular Zone (CMZ), the inner 450 pc of our Galaxy, is an exceptional region where the volume and column densities, gas temperatures, velocity dispersions, etc. are much higher than in the Galactic plane. It has been suggested that the formation of stars and clusters in this area is related to the orbital dynamics of the gas. The complex kinematic structure of the molecular gas was revealed by spectral line observations. However, these results are limited to the line-of-sight-velocities. To fully understand the motions of the gas within the CMZ, we have to know its location in 6D space (3D location + 3D motion). Recent orbital models have tried to explain the inflow of gas towards and its kinematics within this region. With parallax and proper motion measurements of masers in the CMZ we can discriminate among these models and constrain how our Galactic Center is fed with gas.
The statistical rate equations are used to model the OH masers to see if they will always have a one-to-one correspondence with the variation of dust temperature. It is concluded that one has to be careful to argue that the masers will always follow the dust temperature variation profile, and it is possible that different maser transitions from the same molecule respond differently to the same dust temperature variations.
We present the results of sub-millimetre observations on three periodic methanol maser sources. Our results indicate that there are geometric differences between some periodic methanol masers which have different variability profiles.
The full theory of polarized SiO maser emission from the near-circumstellar environment of Asymptotic Giant Branch stars has been the subject of debate, with theories ranging from classical Zeeman origins to predominantly non-Zeeman anisotropic excitation or propagation effects. Features with an internal electric vector position angle (EVPA) rotation of ∼π/2 offer unique constraints on theoretical models. In this work, results are presented for one such feature that persisted across five epochs of SiO ν = 1, J = 1 − 0 VLBA observations of TX Cam. We examine the fit to the predicted dependence of linear polarization and EVPA on angle (θ) between the line of sight and the magnetic field against theoretical models. We also present results on the dependence of mc on θ and their theoretical implications. Finally, we discuss potential causes of the observed differences, and continuing work.
The study of astrophysical maser formation provides a useful probe of the chemical composition and physical conditions of the sources they are observed in. This exploration requires continuously solving the SE equations for the populations of the energy levels in search of conditions that will produce an inversion. After evaluation of available implementations applying the Escape Probability approximation, the masers solver was developed to provide an efficient and robust matrix inversion calculation. This open source package is hosted at https://bitbucket.org/ruby_van_rooyen/masers.
We report the discovery of widespread millimeter-wavelength Class I methanol maser emission associated with protostellar molecular outflows in the massive (proto)cluster G11.92−0.61. Our ~0.5″-resolution SMA and ALMA observations of the 229 GHz and 278 GHz Class I transitions reveal seven and twelve candidate masers, respectively: all 229 GHz masers have 278 GHz counterparts, and five are also coincident with 44 GHz Class I masers previously detected with the VLA. For paired masers, the peak intensities at 229 GHz and 278 GHz are correlated. We also find tentative evidence for a correlation between the strength of millimeter-wavelength Class I maser emission and the energy of the associated molecular outflow.
The final stages of low-mass stellar evolution are characterized by significant mass loss due to stellar pulsations during the AGB phase, which lead to the development of planetary nebulae. Molecular masers of H2O, SiO, and ground state OH transitions are commonly detected in oxygen-rich late-type stars (OH/IR objects). In contrast, excited OH maser transitions are rare. We discuss our study of the carbon-rich pre-planetary nebula CRL618 (a prototypical post-AGB star). Observations conducted in May 2008 with the 305m Arecibo Telescope resulted in the first detection of a 4765MHz OH maser line in a late-type stellar object; the detection was confirmed a few months later also with Arecibo. Subsequent observations in 2015 and 2017 resulted in non-detection of the 4765MHz OH line. Our observations indicate that the 4765MHz OH maser in CRL 618 is highly variable, possibly tracing a short-lived phenomenon during the development of a pre-planetary nebula.