Factors influencing health professionals' use of high-flow nasal cannula therapy for infants with bronchiolitis – A qualitative study

Aim: To explore the factors influencing the use of high-flow nasal cannula (HFNC) therapy for infants with bronchiolitis. Design: Qualitative approach using semi-structured interviews. Methods: The semi-structured interviews (face-to-face or virtual) were conducted between September 2020 and February 2021. Deductive content analysis was used to map key influencing factors for use of HFNC therapy to the Theoretical Domains Framework (TDF). Results: Nineteen interviews were undertaken before reaching thematic saturation (7 nurses, 12 doctors) in emergency departments and paediatric wards from four purposively selected hospitals in Australia and New Zealand. Influencing factors were mapped to eight domains in the TDF with 21 themes identified. Main findings included: (1) Health professionals' expectations of HFNC therapy on patient deterioration, work of breathing and oxygenation; (2) Staff emotions relating to concern and anxiety about deterioration and “need to do something”; (3) Social influences from other health professionals and parents and (4) Environmental factors relating to logistics of care and patient transfer considerations. These factors, combined with the ready availability of HFNC equipment and health professionals having the required skills to administer the therapy, contributed to its initiation. Conclusion: Individual/personal and contextual/environmental factors contribute to the use of HFNC therapy for infants with bronchiolitis. It is evident these influences contribute substantially to increased use, despite evidence-based guidelines recommending a more nuanced approach to this therapy. These findings will inform a targeted implementation intervention to promote evidence-based use of HFNC therapy in infants with bronchiolitis

The effect of patient observation on cranial computed tomography rates in children with minor head trauma

BackgroundManagement of children with minor blunt head trauma often includes a period of observation to determine the need for cranial computed tomography (CT). Our objective was to estimate the effect of planned observation on CT use for each Pediatric Emergency Care Applied Research Network (PECARN) traumatic brain injury (TBI) risk group among children with minor head trauma.MethodsThis was a secondary analysis of a prospective observational study at 10 emergency departments (EDs) in Australia and New Zealand, including 18,471 children 24 hours for head trauma, or hospitalization for ≥ 2 nights in association with a positive cranial CT scan. We estimated the odds of cranial CT use with planned observation, adjusting for patient characteristics, PECARN TBI risk group, history of seizure, time from injury, and hospital clustering, using a generalized linear model with mixed effects.ResultsThe cranial CT rate in the total cohort was 8.6%, and 0.8% had ciTBI. The planned observation group had 4,945 (27%) children compared to 13,526 (73%) in the no planned observation group. Cranial CT use was significantly lower with planned observation (adjusted odds ratio [OR] = 0.2, 95% confidence interval [CI] = 0.1 to 0.1), with no difference in missed ciTBI rates. There was no difference in the odds of cranial CT use with planned observation for the group at very low risk for ciTBI (adjusted OR = 0.9, 95% CI = 0.5 to 1.4). Planned observation was associated with significantly lower cranial CT use in patients at intermediate risk (adjusted OR = 0.2, 95% CI = 0.2 to 0.3) and high risk (adjusted OR = 0.1, 95% CI = 0.0 to 0.1) for ciTBI.ConclusionsEven in a setting with low overall cranial CT rates in children with minor head trauma, planned observation was associated with decreased cranial CT use. This strategy can be safely implemented on selected patients in the PECARN intermediate‐ and higher‐risk groups for ciTBI

On the mechanisms governing gas penetration into a tokamak plasma during a massive gas injection

A new 1D radial fluid code, IMAGINE, is used to simulate the penetration of gas into a tokamak plasma during a massive gas injection (MGI). The main result is that the gas is in general strongly braked as it reaches the plasma, due to mechanisms related to charge exchange and (to a smaller extent) recombination. As a result, only a fraction of the gas penetrates into the plasma. Also, a shock wave is created in the gas which propagates away from the plasma, braking and compressing the incoming gas. Simulation results are quantitatively consistent, at least in terms of orders of magnitude, with experimental data for a D 2 MGI into a JET Ohmic plasma. Simulations of MGI into the background plasma surrounding a runaway electron beam show that if the background electron density is too high, the gas may not penetrate, suggesting a possible explanation for the recent results of Reux et al in JET (2015 Nucl. Fusion 55 093013)

Velocity-space sensitivity of the time-of-flight neutron spectrometer at JET

The velocity-space sensitivities of fast-ion diagnostics are often described by so-called weight functions. Recently, we formulated weight functions showing the velocity-space sensitivity of the often dominant beam-target part of neutron energy spectra. These weight functions for neutron emission spectrometry (NES) are independent of the particular NES diagnostic. Here we apply these NES weight functions to the time-of-flight spectrometer TOFOR at JET. By taking the instrumental response function of TOFOR into account, we calculate time-of-flight NES weight functions that enable us to directly determine the velocity-space sensitivity of a given part of a measured time-of-flight spectrum from TOFOR

Relationship of edge localized mode burst times with divertor flux loop signal phase in JET

A phase relationship is identified between sequential edge localized modes (ELMs) occurrence times in a set of H-mode tokamak plasmas to the voltage measured in full flux azimuthal loops in the divertor region. We focus on plasmas in the Joint European Torus where a steady H-mode is sustained over several seconds, during which ELMs are observed in the Be II emission at the divertor. The ELMs analysed arise from intrinsic ELMing, in that there is no deliberate intent to control the ELMing process by external means. We use ELM timings derived from the Be II signal to perform direct time domain analysis of the full flux loop VLD2 and VLD3 signals, which provide a high cadence global measurement proportional to the voltage induced by changes in poloidal magnetic flux. Specifically, we examine how the time interval between pairs of successive ELMs is linked to the time-evolving phase of the full flux loop signals. Each ELM produces a clear early pulse in the full flux loop signals, whose peak time is used to condition our analysis. The arrival time of the following ELM, relative to this pulse, is found to fall into one of two categories: (i) prompt ELMs, which are directly paced by the initial response seen in the flux loop signals; and (ii) all other ELMs, which occur after the initial response of the full flux loop signals has decayed in amplitude. The times at which ELMs in category (ii) occur, relative to the first ELM of the pair, are clustered at times when the instantaneous phase of the full flux loop signal is close to its value at the time of the first ELM

Variability of outcome measures in trials of intravenous therapy in acute severe paediatric asthma: a systematic review

Objective: To determine the variability of primary and secondary outcomes used in trials of intravenous bronchodilators in children with acute severe paediatric asthma. Methods: Systematic search of MEDLINE, EMBASE, Cochrane CENTRAL and the WHO International Clinical Trials Registry Platform for randomised trials in children (less than18 years) with acute severe paediatric asthma comparing intravenous bronchodilator therapy to another treatment. Initial search was performed on 7 January 2016 with an updated search performed on 6 September 2018. Primary and secondary outcomes were collated. Results: We identified 35 published papers and four registered study protocols. 56 primary outcomes were found, the most common being a clinical asthma score (23/56; 41%). Other identified primary outcomes included bedside tests of respiratory function (11/56; 20%) and measures of length of stay (9/56; 16%). There were a total of 60 different secondary outcomes, the most common were various length of stay measures (24/60; 40%) and adverse events (11/60; 18%). Conclusion: Studies comparing intravenous treatment modalities for children with acute severe paediatric asthma exhibit great variation in the type, number and timing of outcome measures used. There are no patient or family-specific outcomes reported. There is a need to develop international consensus.Charmaine S Gray, Colin VE Powell, Franz E Babl, Stuart R Dalziel, Simon Craig (on behalf of the PREDICT (Paediatric Research In Emergency Departments International Collaborative) Research Networ

Repeat antenatal betamethasone and cardiometabolic outcomes

BACKGROUND: Repeat dose(s) of antenatal betamethasone are recommended for women at <32 weeks with ongoing risk of preterm birth. However, there is concern that use of repeat dose(s) in fetal growth restriction (FGR) may increase the risk of later cardiometabolic disease. METHODS: We undertook secondary analysis of data from the Australasian Collaborative Trial of Repeat Doses of Corticosteroids Midchildhood Outcome Study to determine if FGR influences the effect of repeat betamethasone on growth and cardiometabolic function. At 6 to 8 years, children underwent anthropometry, dual energy x-ray absorptiometry, intravenous glucose tolerance testing, ambulatory blood pressure monitoring, and spirometry. FGR was defined as severe FGR at entry, cesarean delivery for FGR, or customized birth weight below the third centile. RESULTS: Of 266 children assessed, FGR occurred in 43 of 127 (34%) exposed to repeat betamethasone and 44 of 139 (32%) exposed to placebo. There was an interaction between FGR and repeat betamethasone treatment for the effect on height (z score mean difference [95% confidence interval]; FGR: 0.59 [0.01 to 1.17]; non-FGR: −0.29 [−0.69 to 0.10]; P = .01). However, FGR did not influence the effect of repeat betamethasone on cardiometabolic function, which was similar in treatment groups, both in FGR and non-FGR subgroups. CONCLUSIONS: Repeat antenatal betamethasone treatment had no adverse effects on cardiometabolic function, even in the presence of FGR. It may have a positive effect on height in FGR. Clinicians should use repeat doses of antenatal corticosteroids when indicated before preterm birth, regardless of FGR, in view of the associated neonatal benefits.Robert D. Cartwright, Jane E. Harding, Caroline A. Crowther, Wayne S. Cutfield, Malcolm R. Battin, Stuart R. Dalziel, Christopher J.D. McKinlay, on behalf of the ACTORDS Follow-up Grou

Repeat antenatal betamethasone and cardiometabolic outcomes

Antenatal corticosteroid therapy is one of the most effective interventions for preterm birth, resulting in rapid maturation of fetal organ systems. The Australasian Collaborative Trial of Repeat Doses of Steroids (ACTORDS) revealed that neonatal benefit is greatest when antenatal corticosteroids are administered in repeat doses, which can be used to reduce the incidence and severity of preterm lung disease and other serious neonatal morbidity, with absolute benefits similar to that of an initial course of antenatal corticosteroids.Robert D. Cartwright, Jane E. Harding, Caroline A. Crowther, Wayne S. Cutfield, Malcolm R. Battin, Stuart R. Dalziel, Christopher J.D. McKinlay, on behalf of the ACTORDS Follow-up Grou