MAGNEsium Trial In Children (MAGNETIC): a randomised, placebo-controlled trial and economic evaluation of nebulised magnesium sulphate in acute severe asthma in children

Inhaled magnesium versus inhaled salbutamol in rescue treatment for moderate and severe asthma exacerbations in pediatric patients

OBJECTIVE

To compare the effectiveness of inhaled Magnesium Sulfate associated with Salbutamol versus Inhaled Salbutamol alone in patients with moderate and severe asthma exacerbations.

METHOD

Clinical, prospective and randomized study with patients between 3 and 14 years of age divided into two groups: one to receive inhaled salbutamol associated with magnesium sulfate (GSM), the other to receive inhaled salbutamol alone (GS). The sample consisted of 40 patients, 20 patients in each group. Severity was classified using the modified Wood-Downes score, with values between 4 and 7 classified as moderate and 8 or more classified as severe.

RESULTS

Post-inhalation scores decreased both in patients who received salbutamol and magnesium and in those who received salbutamol alone, with no statistically significant difference between the groups.

CONCLUSIONS

Despite the benefits when administered intravenously, inhalation of the drug alone or in combination did not reduce the severity of the exacerbation.

Standard medical therapy with vs. without nebulised magnesium for children with asthma decompensation

Pediatric asthma is a common condition, and its exacerbations can be associated with significant morbidity and mortality. The role of nebulised magnesium as adjunct therapy for children with asthma exacerbations is still unclear. To compare clinical and functional outcomes for children with asthma exacerbation taking either nebulised magnesium sulfate added to standard medical therapy (SMT) versus SMT alone. PubMed, Embase, and Cochrane Library were systematically searched for randomised clinical trials (RCT) comparing the use of SMT with vs. without nebulised magnesium. The outcomes were respiratory rate, heart rate, % predicted peak expiratory flow rate (PEFR), % predicted forced expiratory volume (FEV1), peripheral O2 saturation, asthma severity scores, and need for intravenous (IV) bronchodilator use. Twelve RCTs and 2484 children were included. Mean age was 5.6 (range 2-17) years old, mean baseline % predicted FEV1 was 69.6%, and 28.66% patients were male. Children treated with magnesium had a significantly higher % predicted PEFR (mean difference [MD] 5.33%; 95% confidence interval [CI] 4.75 to 5.90%; p < 0.01). Respiratory rate was significantly lower in the magnesium group (MD -0.70 respirations per minute; 95% CI -1.24 to -0.15; p < 0.01). Need for IV bronchodilators, % predicted FEV1, heart rate, asthma severity scores, and O2 saturation were not significantly different between groups.

CONCLUSION

In children with asthma exacerbation, treatment with nebulised magnesium and SMT was associated with a statistically significant, but small improvement in predicted PEFR and respiratory rate, as compared with SMT alone.

WHAT IS KNOWN

• Magnesium sulfate has bronchodilating properties and aids in the treatment of asthma exacerbation when administered intravenously. • There is no significant evidence of benefit of nebulised magnesium as an adjunct therapy to the standard medical treatment for children with asthma exacerbations.

WHAT IS NEW

• Our study suggests nebulised magnesium sulfate may have a statistically significant, but small benefit in respiratory rate and peak expiratory flow rate. The addition of nebulised magnesium does not seem to increase adverse events.

The Saudi initiative for asthma - 2024 update: Guidelines for the diagnosis and management of asthma in adults and children

The Saudi Initiative for Asthma 2024 (SINA-2024) is the sixth version of asthma guidelines for the diagnosis and management of asthma for adults and children that was developed by the SINA group, a subsidiary of the Saudi Thoracic Society. The main objective of the SINA is to have guidelines that are up-to-date, simple to understand, and easy to use by healthcare workers dealing with asthma patients. To facilitate achieving the goals of asthma management, the SINA Panel approach is mainly based on the assessment of symptom control and risk for both adults and children. The approach to asthma management is aligned for age groups: adults, adolescents, children aged 5-12 years, and children aged <5 years. SINA guidelines have focused more on personalized approaches reflecting a better understanding of disease heterogeneity with the integration of recommendations related to biologic agents, evidence-based updates on treatment, and the role of immunotherapy in management. The medication appendix has also been updated with the addition of recent evidence, new indications for existing medication, and new medications. The guidelines are constructed based on the available evidence, local literature, and the current situation at national and regional levels. There is also an emphasis on patient-doctor partnership in the management that also includes a self-management plan.

Systematic review of economic evaluations for paediatric pulmonary diseases

BACKGROUND

Paediatric pulmonary diseases are the leading causes of mortality amongst children under five globally. Economic evaluations (EEs) seek to guide decision-makers on which health care interventions to adopt to reduce the paediatric pulmonary disease burden. This study aims to systematically review economic evaluations on different aspects of the inpatient management of paediatric pulmonary diseases globally.

METHODS

We systematically reviewed EEs published between 2010 and 2020, with a subsequent search conducted for 2020-2022. We searched PubMed, Web of Science, MEDLINE, Paediatric Economic Database Evaluation (PEDE) and the Cochrane library. We extracted data items guided by the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) checklist. We collected qualitative and quantitative data which we analysed in Microsoft Excel and R software.

RESULTS

Twenty-two articles met the inclusion criteria. Six of the articles were cost-effectiveness analyses, six cost-utility analyses, two cost-minimisation analyses and eight cost analyses. Twelve articles were from high-income countries (HICs) and ten were from low- and middle-income countries (LMICs). Eight articles focused on asthma, eleven on pneumonia, two on asthma and pneumonia, and one on tuberculosis.

CONCLUSION

Conducting more EEs for paediatric pulmonary diseases in LMICs could allow for more evidence-based decision-making to improve paediatric health outcomes.

Economic and health impacts of the Change4Life Food Scanner app: Findings from a randomized pilot and feasibility study

Introduction

The UK Government developed the Change4Life Food Scanner app to provide families with engaging feedback on the nutritional content of packaged foods. There is a lack of research exploring the cost-effectiveness of dietary health promotion apps.

Methods

Through stakeholder engagement, a conceptual model was developed, outlining the pathway by which the Food Scanner app leads to proximal and distal outcomes. The conceptual model informed the development of a pilot randomized controlled trial which investigated the feasibility and acceptability of evaluating clinical outcomes in children and economic effectiveness of the Food Scanner app through a cost-consequence analysis. Parents of 4–11 years-olds (n = 126) were randomized into an app exposure condition (n = 62), or no intervention control (n = 64). Parent-reported Child Health Utility 9 Dimension (CHU9D) outcomes were collected alongside child healthcare resource use and associated costs, school absenteeism and parent productivity losses at baseline and 3 months follow up. Results for the CHU9D were converted into utility scores based on UK adult preference weights. Sensitivity analysis accounted for outliers and multiple imputation methods were adopted for the handling of missing data.

Results

64 participants (51%) completed the study (intervention: n = 29; control: n = 35). There was a mean reduction in quality adjusted life years between groups over the trial period of –0.004 (SD = 0.024, 95% CI: –0.005; 0.012). There was a mean reduction in healthcare costs of –£30.77 (SD = 230.97; 95% CI: –£113.80; £52.26) and a mean reduction in workplace productivity losses of –£64.24 (SD = 241.66, 95% CI: –£147.54; £19.07) within the intervention arm, compared to the control arm, over the data collection period. Similar findings were apparent after multiple imputation.

Discussion

Modest mean differences between study arms may have been due to the exploration of distal outcomes over a short follow-up period. The study was also disrupted due to the coronavirus pandemic, which may have confounded healthcare resource data. Although measures adopted were deemed feasible, the study highlighted difficulties in obtaining data on app development and maintenance costs, as well as the importance of economic modeling to predict long-term outcomes that may not be reliably captured over the short-term.

Clinical trial registration

https://osf.io/, identifier 62hzt.

Safety and Effectiveness of Magnesium Sulphate for Severe Acute Asthma Management Among Under-five Children: Systematic Review and Meta-analysis

Background

Asthma is the common chronic inflammatory disease affecting children. It is usually associated with airway hyper-responsiveness. Globally, the prevalence of asthma among pediatrics population varies from 10% to 30%. Its symptoms range from chronic cough to life-threatening bronchospasm. At emergency department, all patients with acute severe asthma should initially receive oxygen, nebulized β2-agonists, nebulized anticholinergic agent, and corticosteroids. Though bronchodilators act within minutes, corticosteroids may require hours. Magnesium sulphate (MgSO₄) was first considered for treating asthma about 60 years ago. Several case reports were published on its usefulness in decreasing admission and endotracheal intubation. So far, evidence is conflicting to fully employ MgSO₄ for asthma management in children under five.

Objective

This systematic review was aimed to evaluate the effectiveness and safety of MgSO₄ in the treatment of severe acute asthmatic attacks in children.

Methods

A systematic and comprehensive search of literature was performed to identify controlled clinical trials conducted on IV and nebulized MgSO₄ in pediatric patients with acute asthma.

Results

Data generated from three randomized clinical trials were included in the final analysis. In this analysis, intravenous MgSO₄ did not improve respiratory function (RR=1.09, 95%CI: 0.81-1.45) and not safer than conventional treatment (RR=0.38, 95%CI: 0.08-1.67). Similarly, use of nebulized MgSO₄ showed no significant effect on respiratory function (RR=1.05, 95%CI: 0.68-1.64) and more tolerable (RR=0.31, 95%CI: 0.14-0.68).

Conclusion

Intravenous MgSO₄ may not be superior to conventional treatment in moderate to severe acute asthma among children and neither have significant adverse effects. Similarly, nebulized MgSO₄ showed no significant effect on respiratory function in moderate to severe acute asthma in children under five but it seems a safer alternative.

Stating the obvious: intravenous magnesium sulphate should be the first parenteral bronchodilator in paediatric asthma exacerbations unresponsive to first-line therapy

What is the most appropriate second-line intravenous bronchodilator treatment when a child with a severe asthma attack is not responsive to initial inhaled therapy? The second-line treatment options for acute asthma include parenteral β₂-agonists, methylxanthine and magnesium sulphate (MgSO₄). There is a poor evidence-base to inform this decision. This review argues that intravenous MgSO₄ is the obvious treatment of choice for this situation as the initial treatment based on current knowledge.  We describe the mode of action, scope and limitations of MgSO₄, safety profile, economic impact, comparisons of the alternatives, and finally, what the guidelines say.  This review explores the suitability of intravenous MgSO₄ as a pragmatic and safe initial second-line therapy for children unresponsive to initial asthma management.

Bedside Ultrasound Conducted in Kids with distal upper Limb fractures in the Emergency Department (BUCKLED): a protocol for an open-label non-inferiority diagnostic randomised controlled trial

BACKGROUND

Children frequently present to the emergency department (ED) with forearm injuries and often have x-rays to determine if there is a fracture. Bedside ultrasound, also known as point-of-care ultrasound (POCUS), is an alternative diagnostic test used to rapidly diagnose a fracture at the time of examination, without exposing children to ionising radiation. Prospective studies have demonstrated high agreement between POCUS and x-ray findings. However, whether the initial imaging modality affects the patient's medium-term physical function is unknown.

METHODS

This is a multicentre, open-label, non-inferiority randomised controlled trial conducted in Australian EDs. Recruitment will continue until 112 children with distal forearm injuries (including 48 buckle fractures) per trial arm have achieved the primary outcome measure. Patients aged 5-15 years presenting with an isolated, acute, clinically non-angulated, distal forearm injury with suspected fracture will have their initial diagnostic approach randomised to either POCUS, performed by a credentialled practitioner, or x-ray imaging. If a cortical breach fracture is identified on POCUS, the patient will receive x-rays and have usual care. If a buckle fracture is identified, the patient will have their forearm placed in a splint and be discharged home. Patients will be followed up at 1, 4 and 8 weeks. The primary outcome is upper limb physical function at 4 weeks, as determined by the Pediatric Upper Extremity Short Patient-Reported Outcomes Measurement Information System (PROMIS) tool. Secondary outcomes include healthcare costs, satisfaction, pain, complications, rates of imaging, ED length of stay and diagnostic accuracy.

DISCUSSION

If POCUS is non-inferior to x-ray in terms of patient's medium-term physical function, it may have an effect on overall health care resource use, including the number of x-ray performed and earlier ED discharge. Although prospective studies have confirmed the accuracy of POCUS, this will be the first RCT to assess non-inferiority of functional outcomes of POCUS to diagnose non-angulated paediatric distal forearm injuries, compared to x-ray. POCUS may be of particular importance in settings where access to x-ray imaging can be limited either during or after-hours, as it can aid the triaging and management of patients.

TRIAL REGISTRATION

Prospectively registered with the ANZCTR on 29 May 2020 ( ACTRN12620000637943 ).

Health-Related Quality-of-Life and Cost Utility Analyses in Critical Care: A Systematic Review

OBJECTIVES

Cost utility analyses compare the costs and health outcome of interventions, with a denominator of quality-adjusted life year, a generic health utility measure combining both quality and quantity of life. Cost utility analyses are difficult to compare when methods are not standardized. It is unclear how cost utility analyses are measured/reported in critical care and what methodologic challenges cost utility analyses pose in this setting. This may lead to differences precluding cost utility analyses comparisons. Therefore, we performed a systematic review of cost utility analyses conducted in critical care. Our objectives were to understand: 1) methodologic characteristics, 2) how health-related quality-of-life was measured/reported, and 3) what costs were reported/measured.

DESIGN

Systematic review.

DATA SOURCES

We systematically searched for cost utility analyses in critical care in MEDLINE, Embase, American College of Physicians Journal Club, CENTRAL, Evidence-Based Medicine Reviews' selected subset of archived versions of UK National Health Service Economic Evaluation Database, Database of Abstracts of Reviews of Effects, and American Economic Association electronic databases from inception to April 30, 2020.

SETTING

Adult ICUs.

PATIENTS

Adult critically ill patients.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 8,926 citations, 80 cost utility analyse studies were eligible. The time horizon most commonly reported was lifetime (59%). For health utility reporting, health-related quality-of-life was infrequently measured (29% reported), with only 5% of studies reporting baseline health-related quality-of-life. Indirect utility measures (generic, preference-based health utility measurement tools) were reported in 85% of studies (majority Euro-quality-of-life-5 Domains, 52%). Methods of estimating health-related quality-of-life were seldom used when the patient was incapacitated: imputation (19%), assigning fixed utilities for incapacitation (19%), and surrogates reporting on behalf of incapacitated patients (5%). For cost utility reporting transparency, separate incremental costs and quality-adjusted life years were both reported in only 76% of studies. Disaggregated quality-adjusted life years (reporting separate health utility and life years) were described in only 34% of studies.

CONCLUSIONS

We identified deficiencies which warrant recommendations (standardized measurement/reporting of resource use/unit costs/health-related quality-of-life/methodological preferences) for improved design, conduct, and reporting of future cost utility analyses in critical care.

Possibility of magnesium supplementation for supportive treatment in patients with COVID-19

Magnesium as an enzymatic activator is essential for various physiological functions such as cell cycle, metabolic regulation, muscle contraction, and vasomotor tone. A growing body of evidence supports that magnesium supplementation (mainly magnesium sulfate and magnesium oxide) prevents or treats various types of disorders or diseases related to respiratory system, reproductive system, nervous system, digestive system, and cardiovascular system as well as kidney injury, diabetes and cancer. The ongoing pandemic coronavirus disease 19 (COVID-19) characterized by respiratory tract symptoms with different degrees of important organ and tissue damages has attracted global attention. Particularly, effective drugs are still lacking in the COVID-19 therapy. In this review, we find and summarize the effectiveness of magnesium supplementation on the disorders or diseases, and provide a reference to the possibility of magnesium supplementation for supportive treatment in patients with COVID-19.

Inhalations with Brine Solution from the 'Wieliczka' Salt Mine Diminish Airway Hyperreactivity and Inflammation in a Murine Model of Non-Atopic Asthma

Inhalations with brine solutions are old but underestimated add-ons to pharmacological treatments of inflammatory lung diseases. Although widely used, not all features underlying their action on the respiratory system have been explored. The aim of the present study was to elucidate the mechanism of the beneficial action of inhalations of brine solution from the 'Wieliczka' Salt Mine, a Polish health resort, in a murine model of non-atopic asthma. Asthma was induced in BALB/c mice by skin sensitization with dinitrofluorobenzene followed by an intratracheal challenge of cognate hapten. All animals underwent 12 inhalation sessions with brine solution, pure water or physiological saline. Control mice were not inhaled. We found that brine inhalations reduced, as compared to non-inhaled mice, the typical asthma-related symptoms, like airway hyperreactivity (AHR), the infiltration of pro-inflammatory cells into the bronchial tree, and the inflammation of the airways at the level of pro-inflammatory cytokines IL-1α, IL-1β and IL-6. The level of the anti-inflammatory IL-10 was elevated in brine-inhaled mice. Inhalations with pure water increased AHR, whereas saline had no influence, either on AHR or cytokine concentrations. These observations indicate that inhalations with a brine solution from the 'Wieliczka' Salt Mine diminish the asthma-related symptoms, mostly by reducing the inflammatory status and by decreasing AHR.

Acute severe paediatric asthma: study protocol for the development of a core outcome set, a Pediatric Emergency Reserarch Networks (PERN) study

BACKGROUND

Acute severe childhood asthma is an infrequent, but potentially life-threatening emergency condition. There is a wide range of different approaches to this condition, with very little supporting evidence, leading to significant variation in practice. To improve knowledge in this area, there must first be consensus on how to conduct clinical trials, so that valid comparisons can be made between future studies. We have formed an international working group comprising paediatricians and emergency physicians from North America, Europe, Asia, the Middle East, Africa, South America, Central America, Australasia and the United Kingdom.

METHODS/DESIGN

A 5-stage approach will be used: (1) a comprehensive list of outcomes relevant to stakeholders will be compiled through systematic reviews and qualitative interviews with patients, families, and clinicians; (2) Delphi methodology will be applied to reduce the comprehensive list to a core outcome set; (3) we will review current clinical practice guidelines, existing clinical trials, and literature on bedside assessment of asthma severity. We will then identify practice differences in tne clinical assessment of asthma severity, and determine whether further prospective work is needed to achieve agreement on inclusion criteria for clinical trials in acute paediatric asthma in the emergency department (ED) setting; (4) a retrospective chart review in Australia and New Zealand will identify the incidence of serious clinical complications such as intubation, ICU admission, and death in children hospitalized with acute severe asthma. Understanding the incidence of such outcomes will allow us to understand how common (and therefore how feasible) particular outcomes are in asthma in the ED setting; and finally (5) a meeting of the Pediatric Emergency Research Networks (PERN) asthma working group will be held, with invitation of other clinicians interested in acute asthma research, and patients/families. The group will be asked to achieve consensus on a core set of outcomes and to make recommendations for the conduct of clinical trials in acute severe asthma. If this is not possible, the group will agree on a series of prioritized steps to achieve this aim.

DISCUSSION

The development of an international consensus on core outcomes is an important first step towards the development of consensus guidelines and standardised protocols for randomized controlled trials (RCTs) in this population. This will enable us to better interpret and compare future studies, reduce risks of study heterogeneity and outcome reporting bias, and improve the evidence base for the management of this important condition.

Limitations of the results from randomized clinical trials involving intravenous and nebulised magnesium sulphate in adults with severe acute asthma

The role of intravenous (IV) or nebulised magnesium sulphate (MgSO₄) in the treatment of severe acute asthma in adults is unclear. A controversy exists regarding its efficacy. In children MgSO₄ has a more evident clinical effect, but the child population has not been considered in this work. The applicability of the results from randomized clinical trials (RCTs) involving MgSO₄ in adult population is questioned in the optimal treatment of asthma exacerbations. According to the newest guidelines from the Global Initiative for Asthma (GINA), optimal treatment in the emergency department (ED) is based on short-acting beta₂-agonists (SABA), oral or IV corticosteroids (CS), short acting muscarinic antagonists (SAMA) and the controlled oxygen therapy. Further improvements with IV or nebulised MgSO₄ were assessed in a recent large multicentre, double-blind, placebo-controlled randomized 3 Mg trial, which failed to demonstrate clinical benefit. Several other RCTs found some benefit with MgSO₄, although the majority lacked some treatment options that are used in the optimal treatment of asthma exacerbations. Therefore, we reviewed the limitations of RCTs of IV or nebulised MgSO₄ in adults with acute asthma, with the aim to answer in which subpopulation MgSO₄ could be beneficial.

The Saudi Initiative for Asthma - 2019 Update: Guidelines for the diagnosis and management of asthma in adults and children

This is the fourth version of the updated guidelines for the diagnosis and management of asthma, developed by the Saudi Initiative for Asthma (SINA) group, a subsidiary of the Saudi Thoracic Society. The main objective of the SINA is to have guidelines that are up to date, simple to understand, and easy to use by healthcare workers dealing with asthma patients. To facilitate achieving the goals of asthma management, the SINA panel approach is mainly based on the assessment of symptom control and risk for both adults and children. The approach to asthma management is now more aligned for different age groups. The guidelines have focused more on personalized approaches reflecting better understanding of disease heterogeneity with integration of recommendations related to biologic agents, evidence-based updates on treatment, and role of immunotherapy in management. The medication appendix has also been updated with the addition of recent evidence, new indications for existing medication, and new medications. The guidelines are constructed based on the available evidence, local literature, and current situation at national and regional levels. There is also an emphasis on patient–doctor partnership in the management that also includes a self-management plan.

Cost Effectiveness of Pharmacological Treatments for Asthma: A Systematic Review

OBJECTIVE

The objective of this article was to summarize the findings of all the available studies on alternative pharmacological treatments for asthma and assess their methodological quality, as well as to identify the main drivers of the cost effectiveness of pharmacological treatments for the disease.

METHODS

A systematic review of the literature in seven electronic databases was conducted in order to identify all the available health economic evidence on alternative pharmacological treatments for asthma published up to April 2017. The reporting quality of the included studies was assessed using the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) statement.

RESULTS

A total of 72 studies were included in the review, classified as follows: medications for acute asthma treatment (n = 5, 6.9%); inhaled corticosteroids (ICS) administered alone or in conjunction with long-acting β-agonists (LABA) or tiotropium for chronic asthma treatment (n = 38, 52.8%); direct comparisons between different combinations of ICS, ICS/LABA, leukotriene receptor antagonists (LTRA), and sodium cromoglycate for chronic asthma treatment (n = 14, 19.4%); and omalizumab for chronic asthma treatment (n = 15, 20.8%). ICS were reported to be cost effective when compared with LTRA for the management of persistent asthma. In patients with inadequately controlled asthma taking ICS, the addition of long-acting β-agonist (LABA) preparations has been demonstrated to be cost effective, especially when combinations of ICS/LABA containing formoterol are used for both maintenance and reliever therapy. In patients with uncontrolled severe persistent allergic asthma, omalizumab therapy could be cost effective in a carefully selected subgroup of patients with the more severe forms of the disease. The quality of reporting in the studies, according to the CHEERS checklist, was very uneven. The main cost-effectiveness drivers identified were the cost or rate of asthma exacerbations, the cost or rate of the use of asthma medications, the asthma mortality risk, and the rate of utilization of health services for asthma.

CONCLUSIONS

The present findings are in line with the pharmacological recommendations for stepwise management of asthma given in the most recent evidence-based clinical practice guidelines for the disease. The identified reporting quality of the available health economic evidence is useful for identifying aspects where there is room for improvement in future asthma cost-effectiveness studies.

Investigation of one-stage meta-analysis methods for joint longitudinal and time-to-event data through simulation and real data application

Background: Joint modeling of longitudinal and time‐to‐event data is often advantageous over separate longitudinal or time‐to‐event analyses as it can account for study dropout, error in longitudinally measured covariates, and correlation between longitudinal and time‐to‐event outcomes. The current literature on joint modeling focuses mainly on the analysis of single studies with a lack of methods available for the meta‐analysis of joint data from multiple studies.

Methods: We investigate a variety of one‐stage methods for the meta‐analysis of joint longitudinal and time‐to‐event outcome data. These methods are applied to the INDANA dataset to investigate longitudinally measured systolic blood pressure, with each of time to death, time to myocardial infarction, and time to stroke. Results are compared to separate longitudinal or time‐to‐event meta‐analyses. A simulation study is conducted to contrast separate versus joint analyses over a range of scenarios.

Results: The performance of the examined one‐stage joint meta‐analytic models varied. Models that accounted for between study heterogeneity performed better than models that ignored it. Of the examined methods to account for between study heterogeneity, under the examined association structure, fixed effect approaches appeared preferable, whereas methods involving a baseline hazard stratified by study were least time intensive.

Conclusions: One‐stage joint meta‐analytic models that accounted for between study heterogeneity using a mix of fixed effects or a stratified baseline hazard were reliable; however, models examined that included study level random effects in the association structure were less reliable.

Guideline on management of the acute asthma attack in children by Italian Society of Pediatrics

BACKGROUND

Acute asthma attack is a frequent condition in children. It is one of the most common reasons for emergency department (ED) visit and hospitalization. Appropriate care is fundamental, considering both the high prevalence of asthma in children, and its life-threatening risks. Italian Society of Pediatrics recently issued a guideline on the management of acute asthma attack in children over age 2, in ambulatory and emergency department settings.

METHODS

The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology was adopted. A literature search was performed using the Cochrane Library and Medline/PubMed databases, retrieving studies in English or Italian and including children over age 2 year.

RESULTS

Inhaled ß2 agonists are the first line drugs for acute asthma attack in children. Ipratropium bromide should be added in moderate/severe attacks. Early use of systemic steroids is associated with reduced risk of ED visits and hospitalization. High doses of inhaled steroids should not replace systemic steroids. Aminophylline use should be avoided in mild/moderate attacks. Weak evidence supports its use in life-threatening attacks. Epinephrine should not be used in the treatment of acute asthma for its lower cost / benefit ratio, compared to β2 agonists. Intravenous magnesium solphate could be used in children with severe attacks and/or forced expiratory volume1 (FEV1) lower than 60% predicted, unresponsive to initial inhaled therapy. Heliox could be administered in life-threatening attacks. Leukotriene receptor antagonists are not recommended.

CONCLUSIONS

This Guideline is expected to be a useful resource in managing acute asthma attacks in children over age 2.

PLEASANT: Preventing and Lessening Exacerbations of Asthma in School-age children Associated with a New Term - a cluster randomised controlled trial and economic evaluation

BACKGROUND

Asthma episodes and deaths are known to be seasonal. A number of reports have shown peaks in asthma episodes in school-aged children associated with the return to school following the summer vacation. A fall in prescription collection in the month of August has been observed, and was associated with an increase in the number of unscheduled contacts after the return to school in September.

OBJECTIVE

The primary objective of the study was to assess whether or not a NHS-delivered public health intervention reduces the September peak in unscheduled medical contacts.

DESIGN

Cluster randomised trial, with the unit of randomisation being 142 NHS general practices, and trial-based economic evaluation.

SETTING

Primary care.

INTERVENTION

A letter sent (n = 70 practices) in July from their general practitioner (GP) to parents/carers of school-aged children with asthma to remind them of the importance of taking their medication, and to ensure that they have sufficient medication prior to the start of the new school year in September. The control group received usual care.

MAIN OUTCOME MEASURES

The primary outcome measure was the proportion of children aged 5-16 years who had an unscheduled medical contact in September 2013. Supporting end points included the proportion of children who collected prescriptions in August 2013 and unscheduled contacts through the following 12 months. Economic end points were quality-adjusted life-years (QALYs) gained and costs from an NHS and Personal Social Services perspective.

RESULTS

There is no evidence of effect in terms of unscheduled contacts in September. Among children aged 5-16 years, the odds ratio (OR) was 1.09 [95% confidence interval (CI) 0.96 to 1.25] against the intervention. The intervention did increase the proportion of children collecting a prescription in August (OR 1.43, 95% CI 1.24 to 1.64) as well as scheduled contacts in the same month (OR 1.13, 95% CI 0.84 to 1.52). For the wider time intervals (September-December 2013 and September-August 2014), there is weak evidence of the intervention reducing unscheduled contacts. The intervention did not reduce unscheduled care in September, although it succeeded in increasing the proportion of children collecting prescriptions in August as well as having scheduled contacts in the same month. These unscheduled contacts in September could be a result of the intervention, as GPs may have wanted to see patients before issuing a prescription. The economic analysis estimated a high probability that the intervention was cost-saving, for baseline-adjusted costs, across both base-case and sensitivity analyses. There was no increase in QALYs.

LIMITATION

The use of routine data led to uncertainty in the coding of medical contacts. The uncertainty was mitigated by advice from a GP adjudication panel.

CONCLUSIONS

The intervention did not reduce unscheduled care in September, although it succeeded in increasing the proportion of children both collecting prescriptions and having scheduled contacts in August. After September there is weak evidence in favour of the intervention. The intervention had a favourable impact on costs but did not demonstrate any impact on QALYs. The results of the trial indicate that further work is required on assessing and understanding adherence, both in terms of using routine data to make quantitative assessments, and through additional qualitative interviews with key stakeholders such as practice nurses, GPs and a wider group of children with asthma.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN03000938.

FUNDING DETAILS

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 93. See the HTA programme website for further project information.

Investigation of 2-stage meta-analysis methods for joint longitudinal and time-to-event data through simulation and real data application

Background

Joint modelling of longitudinal and time‐to‐event data is often preferred over separate longitudinal or time‐to‐event analyses as it can account for study dropout, error in longitudinally measured covariates, and correlation between longitudinal and time‐to‐event outcomes. The joint modelling literature focuses mainly on the analysis of single studies with no methods currently available for the meta‐analysis of joint model estimates from multiple studies.

Methods

We propose a 2‐stage method for meta‐analysis of joint model estimates. These methods are applied to the INDANA dataset to combine joint model estimates of systolic blood pressure with time to death, time to myocardial infarction, and time to stroke. Results are compared to meta‐analyses of separate longitudinal or time‐to‐event models. A simulation study is conducted to contrast separate versus joint analyses over a range of scenarios.

Results

Using the real dataset, similar results were obtained by using the separate and joint analyses. However, the simulation study indicated a benefit of use of joint rather than separate methods in a meta‐analytic setting where association exists between the longitudinal and time‐to‐event outcomes.

Conclusions

Where evidence of association between longitudinal and time‐to‐event outcomes exists, results from joint models over standalone analyses should be pooled in 2‐stage meta‐analyses.

Inhaled magnesium sulfate in the treatment of acute asthma

BACKGROUND

Asthma exacerbations can be frequent and range in severity from mild to life-threatening. The use of magnesium sulfate (MgSO₄) is one of numerous treatment options available during acute exacerbations. While the efficacy of intravenous MgSO₄ has been demonstrated, the role of inhaled MgSO₄ is less clear.

OBJECTIVES

To determine the efficacy and safety of inhaled MgSO₄ administered in acute asthma.

SPECIFIC AIMS

to quantify the effects of inhaled MgSO₄ I) in addition to combination treatment with inhaled β₂-agonist and ipratropium bromide; ii) in addition to inhaled β₂-agonist; and iii) in comparison to inhaled β₂-agonist.

SEARCH METHODS

We identified randomised controlled trials (RCTs) from the Cochrane Airways Group register of trials and online trials registries in September 2017. We supplemented these with searches of the reference lists of published studies and by contact with trialists.

SELECTION CRITERIA

RCTs including adults or children with acute asthma were eligible for inclusion in the review. We included studies if patients were treated with nebulised MgSO₄ alone or in combination with β₂-agonist or ipratropium bromide or both, and were compared with the same co-intervention alone or inactive control.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial selection, data extraction and risk of bias. We made efforts to collect missing data from authors. We present results, with their 95% confidence intervals (CIs), as mean differences (MDs) or standardised mean differences (SMDs) for pulmonary function, clinical severity scores and vital signs; and risk ratios (RRs) for hospital admission. We used risk differences (RDs) to analyse adverse events because events were rare.

MAIN RESULTS

Twenty-five trials (43 references) of varying methodological quality were eligible; they included 2907 randomised patients (2777 patients completed). Nine of the 25 included studies involved adults; four included adult and paediatric patients; eight studies enrolled paediatric patients; and in the remaining four studies the age of participants was not stated. The design, definitions, intervention and outcomes were different in all 25 studies; this heterogeneity made direct comparisons difficult. The quality of the evidence presented ranged from high to very low, with most outcomes graded as low or very low. This was largely due to concerns about the methodological quality of the included studies and imprecision in the pooled effect estimates. Inhaled magnesium sulfate in addition to inhaled β₂-agonist and ipratropiumWe included seven studies in this comparison. Although some individual studies reported improvement in lung function indices favouring the intervention group, results were inconsistent overall and the largest study reporting this outcome found no between-group difference at 60 minutes (MD -0.3 % predicted peak expiratory flow rate (PEFR), 95% CI -2.71% to 2.11%). Admissions to hospital at initial presentation may be reduced by the addition of inhaled magnesium sulfate (RR 0.95, 95% CI 0.91 to 1.00; participants = 1308; studies = 4; I² = 52%) but no difference was detected for re-admissions or escalation of care to ITU/HDU. Serious adverse events during admission were rare. There was no difference between groups for all adverse events during admission (RD 0.01, 95% CI -0.03 to 0.05; participants = 1197; studies = 2). Inhaled magnesium sulfate in addition to inhaled β₂-agonistWe included 13 studies in this comparison. Although some individual studies reported improvement in lung function indices favouring the intervention group, none of the pooled results showed a conclusive benefit as measured by FEV1 or PEFR. Pooled results for hospital admission showed a point estimate that favoured the combination of MgSO₄ and β₂-agonist, but the confidence interval includes the possibility of admissions increasing in the intervention group (RR 0.78, 95% CI 0.52 to 1.15; participants = 375; studies = 6; I² = 0%). There were no serious adverse events reported by any of the included studies and no between-group difference for all adverse events (RD -0.01, 95% CI -0.05 to 0.03; participants = 694; studies = 5). Inhaled magnesium sulfate versus inhaled β₂-agonistWe included four studies in this comparison. The evidence for the efficacy of β₂-agonists in acute asthma is well-established and therefore this could be considered a historical comparison. Two studies reported a benefit of β₂-agonist over MgSO₄ alone for PEFR and two studies reported no difference; we did not pool these results. Admissions to hospital were only reported by one small study and events were rare, leading to an uncertain result. No serious adverse events were reported in any of the studies in this comparison; one small study reported mild to moderate adverse events but the result is imprecise.

AUTHORS' CONCLUSIONS

Treatment with nebulised MgSO₄ may result in modest additional benefits for lung function and hospital admission when added to inhaled β₂-agonists and ipratropium bromide, but our confidence in the evidence is low and there remains substantial uncertainty. The recent large, well-designed trials have generally not demonstrated clinically important benefits. Nebulised MgSO₄ does not appear to be associated with an increase in serious adverse events. Individual studies suggest that those with more severe attacks and attacks of shorter duration may experience a greater benefit but further research into subgroups is warranted.Despite including 24 trials in this review update we were unable to pool data for all outcomes of interest and this has limited the strength of the conclusions reached. A core outcomes set for studies in acute asthma is needed. This is particularly important in paediatric studies where measuring lung function at the time of an exacerbation may not be possible. Placebo-controlled trials in patients not responding to standard maximal treatment, including inhaled β₂-agonists and ipratropium bromide and systemic steroids, may help establish if nebulised MgSO₄ has a role in acute asthma. However, the accumulating evidence suggests that a substantial benefit may be unlikely.

Asthma Cost-Effectiveness Analyses: Are We Using the Recommended Outcomes in Estimating Value?

BACKGROUND

Asthma medication cost-effectiveness analyses (CEAs) lack the qualitative assessment regarding whether they capture the National Institutes for Health (NIH) 2012 recommended outcomes necessary to allow robust cross-study comparisons.

OBJECTIVE

We aimed to assess the current asthma outcomes used in CEAs and recommend a direction for improvement.

METHODS

We performed a systematic search using electronic databases including PubMed, EMBASE, Tufts CEA registry, Cochrane, and NHSEED from January 2010 through December 2015. Key words included (1) cost-effectiveness, cost-utility, economic evaluation, health economics, or cost-benefit AND (2) asthma. All CEA studies evaluating 1 or more asthma medication were included. Authors assessed each CEA study with respect to asthma-specific NIH outcome recommendations including core (hospitalizations, emergency department visits, outpatient visits, medication, interventions costs), supplemental (visit categories and work/school absence), and emerging (academic/job-related) asthma outcomes. Besides outcomes of each CEA, issues that could prevent robust cross-study comparison were identified and thematically summarized.

RESULTS

A total of 12 pre-NIH and 14 post-NIH recommendation CEAs were included. Eleven (91.7%) and 14 (100%) of the pre-/post-NIH studies included at least 1 core outcome, respectively. Of the 26 total studies, 7 (26.9%) included asthma-specific outpatient visit categories, 6 (23.1%) included asthma school or work absences, 5 (19.2%) included respiratory health care use, and none of the studies included emerging outcomes. Other issues that hamper cross-study comparison include lack of standardized cost data, time frames, quality-of-life measures, and incorporation of adherence.

CONCLUSIONS

Although the use of NIH-recommended asthma core outcomes has improved, there is still room for improvement in using supplemental and emerging outcomes. To allow robust cross-study comparisons, future work should focus on further standardizing of data sources and methods.

Health-Related Resource-Use Measurement Instruments for Intersectoral Costs and Benefits in the Education and Criminal Justice Sectors

BACKGROUND

Intersectoral costs and benefits (ICBs), i.e. costs and benefits of healthcare interventions outside the healthcare sector, can be a crucial component in economic evaluations from the societal perspective. Pivotal to their estimation is the existence of sound resource-use measurement (RUM) instruments; however, RUM instruments for ICBs in the education or criminal justice sectors have not yet been systematically collated or their psychometric quality assessed. This review aims to fill this gap.

METHODS

To identify relevant instruments, the Database of Instruments for Resource Use Measurement (DIRUM) was searched. Additionally, a systematic literature review was conducted in seven electronic databases to detect instruments containing ICB items used in economic evaluations. Finally, studies evaluating the psychometric quality of these instruments were searched.

RESULTS

Twenty-six unique instruments were included. Most frequently, ICB items measured school absenteeism, tutoring, classroom assistance or contacts with legal representatives, police custody/prison detainment and court appearances, with the highest number of items listed in the Client Service Receipt Inventory/Client Sociodemographic and Service Receipt Inventory/Client Service Receipt Inventory-Children's Version (CSRI/CSSRI/CSRI-C), Studying the Scope of Parental Expenditures (SCOPE) and Self-Harm Intervention, Family Therapy (SHIFT) instruments. ICBs in the education sector were especially relevant for age-related developmental disorders and chronic diseases, while criminal justice resource use seems more important in mental health, including alcohol-related disorders or substance abuse. Evidence on the validity or reliability of ICB items was published for two instruments only.

CONCLUSION

With a heterogeneous variety of ICBs found to be relevant for several disease areas but many ICB instruments applied in one study only (21/26 instruments), setting-up an international task force to, for example, develop an internationally adaptable instrument is recommended.

Integrative Medicine for Respiratory Conditions: Asthma and Chronic Obstructive Pulmonary Disease

Asthma and chronic obstructive pulmonary disease are 2 common chronic respiratory disorders in primary care that cause considerable morbidity and mortality. This article reviews disease pathophysiology and outlines an integrative, multidimensional approach to the evaluation and management of these conditions, including pharmacotreatment, nutrition, supplements, self-care strategies, mind-body therapies, and other integrative modalities.

Methodological Issues Surrounding the Use of Baseline Health-Related Quality of Life Data to Inform Trial-Based Economic Evaluations of Interventions Within Emergency and Critical Care Settings: A Systematic Literature Review

BACKGROUND

Trial-based cost-utility analyses require health-related quality of life data that generate utility values in order to express health outcomes in terms of quality-adjusted life years (QALYs). Assessments of baseline health-related quality of life are problematic where trial participants are incapacitated or critically ill at the time of randomisation. This review aims to identify and critique methods for handling non-availability of baseline health-related quality of life data in trial-based cost-utility analyses within emergency and critical illness settings.

METHODS

A systematic literature review was conducted, following PRISMA guidelines, to identify trial-based cost-utility analyses of interventions within emergency and critical care settings. Databases searched included the National Institute for Health Research (NIHR) Journals Library (1991-July 2016), Cochrane Library (all years); National Health Service (NHS) Economic Evaluation Database (all years) and Ovid MEDLINE/Embase (without time restriction). Strategies employed to handle non-availability of baseline health-related quality of life data in final QALY estimations were identified and critiqued.

RESULTS

A total of 4224 published reports were screened, 19 of which met the study inclusion criteria (mean trial size 1670): 14 (74 %) from the UK, four (21%) from other European countries and one (5%) from India. Twelve studies (63%) were based in emergency departments and seven (37%) in intensive care units. Only one study was able to elicit patient-reported health-related quality of life at baseline. To overcome the lack of baseline data when estimating QALYs, eight studies (42%) assigned a fixed utility weight corresponding to either death, an unconscious health state or a country-specific norm to patients at baseline, four (21%) ignored baseline utilities, three (16%) applied values from another study, one (5%) generated utility values via retrospective recall and one (5%) elicited utilities from experts. A preliminary exploration of these methods shows that incremental QALY estimation is unlikely to be biased if balanced trial allocation is achieved and subsequent collection of health-related quality of life data occurs at the earliest possible opportunity following commencement of treatment, followed by an adequate number of follow-up assessments.

CONCLUSION

Trial-based cost-utility analyses within emergency and critical illness settings have applied different methods for QALY estimation, employing disparate assumptions about the health-related quality of life of patients at baseline. Where baseline measurement is not practical, measurement at the earliest opportunity following commencement of treatment should minimise bias in QALY estimation.

Magnesium sulfate in pediatric anesthesia: the Super Adjuvant

Magnesium is an essential chemical element in all organisms, intervening in most cellular enzymatic reactions; thus, its importance in homeostasis and as a therapeutic tool in highly challenging patients such as pediatrics. The primary purpose of this paper was to review the role of magnesium sulfate as an adjuvant drug in pediatric anesthesia. This compound already has the scientific backing in certain aspects such as analgesia or muscle relaxation, but only theoretical or empirical backing in others such as organ protection or inflammation, where it seems to be promising. The multitude of potential applications in pediatric anesthesia, its high safety, and low cost make magnesium sulfate could be considered a Super Adjuvant.

Joint models for longitudinal and time-to-event data: a review of reporting quality with a view to meta-analysis

BACKGROUND

Joint models for longitudinal and time-to-event data are commonly used to simultaneously analyse correlated data in single study cases. Synthesis of evidence from multiple studies using meta-analysis is a natural next step but its feasibility depends heavily on the standard of reporting of joint models in the medical literature. During this review we aim to assess the current standard of reporting of joint models applied in the literature, and to determine whether current reporting standards would allow or hinder future aggregate data meta-analyses of model results.

METHODS

We undertook a literature review of non-methodological studies that involved joint modelling of longitudinal and time-to-event medical data. Study characteristics were extracted and an assessment of whether separate meta-analyses for longitudinal, time-to-event and association parameters were possible was made.

RESULTS

The 65 studies identified used a wide range of joint modelling methods in a selection of software. Identified studies concerned a variety of disease areas. The majority of studies reported adequate information to conduct a meta-analysis (67.7% for longitudinal parameter aggregate data meta-analysis, 69.2% for time-to-event parameter aggregate data meta-analysis, 76.9% for association parameter aggregate data meta-analysis). In some cases model structure was difficult to ascertain from the published reports.

CONCLUSIONS

Whilst extraction of sufficient information to permit meta-analyses was possible in a majority of cases, the standard of reporting of joint models should be maintained and improved. Recommendations for future practice include clear statement of model structure, of values of estimated parameters, of software used and of statistical methods applied.

Modelling variable dropout in randomised controlled trials with longitudinal outcomes: application to the MAGNETIC study

BACKGROUND

Clinical trials with longitudinally measured outcomes are often plagued by missing data due to patients withdrawing or dropping out from the trial before completing the measurement schedule. The reasons for dropout are sometimes clearly known and recorded during the trial, but in many instances these reasons are unknown or unclear. Often such reasons for dropout are non-ignorable. However, the standard methods for analysing longitudinal outcome data assume that missingness is non-informative and ignore the reasons for dropout, which could result in a biased comparison between the treatment groups.

METHODS

In this article, as a post hoc analysis, we explore the impact of informative dropout due to competing reasons on the evaluation of treatment effect in the MAGNETIC trial, the largest randomised placebo-controlled study to date comparing the addition of nebulised magnesium sulphate to standard treatment in acute severe asthma in children. We jointly model longitudinal outcome and informative dropout process to incorporate the information regarding the reasons for dropout by treatment group.

RESULTS

The effect of nebulised magnesium sulphate compared with standard treatment is evaluated more accurately using a joint longitudinal-competing risk model by taking account of such complexities. The corresponding estimates indicate that the rate of dropout due to good prognosis is about twice as high in the magnesium group compared with standard treatment.

CONCLUSIONS

We emphasise the importance of identifying reasons for dropout and undertaking an appropriate statistical analysis accounting for such dropout. The joint modelling approach accounting for competing reasons for dropout is proposed as a general approach for evaluating the sensitivity of conclusions to assumptions regarding missing data in clinical trials with longitudinal outcomes.

TRIAL REGISTRATION

EudraCT number 2007-006227-12 . Registration date 18 Mar 2008.

The Saudi Initiative for Asthma - 2016 update: Guidelines for the diagnosis and management of asthma in adults and children

This is an updated guideline for the diagnosis and management of asthma, developed by the Saudi Initiative for Asthma (SINA) group, a subsidiary of the Saudi Thoracic Society. The main objective of SINA is to have guidelines that are up to date, simple to understand and easy to use by nonasthma specialists, including primary care and general practice physicians. SINA approach is mainly based on symptom control and assessment of risk as it is the ultimate goal of treatment. The new SINA guidelines include updates of acute and chronic asthma management, with more emphasis on the use of asthma control in the management of asthma in adults and children, inclusion of a new medication appendix, and keeping consistency on the management at different age groups. The section on asthma in children is rewritten and expanded where the approach is stratified based on the age. The guidelines are constructed based on the available evidence, local literature, and the current situation in Saudi Arabia. There is also an emphasis on patient-doctor partnership in the management that also includes a self-management plan.

Measuring Health Utilities in Children and Adolescents: A Systematic Review of the Literature

Background

The objective of this review was to evaluate the use of all direct and indirect methods used to estimate health utilities in both children and adolescents. Utilities measured pre- and post-intervention are combined with the time over which health states are experienced to calculate quality-adjusted life years (QALYs). Cost-utility analyses (CUAs) estimate the cost-effectiveness of health technologies based on their costs and benefits using QALYs as a measure of benefit. The accurate measurement of QALYs is dependent on using appropriate methods to elicit health utilities.

Objective

We sought studies that measured health utilities directly from patients or their proxies. We did not exclude those studies that also included adults in the analysis, but excluded those studies focused only on adults.

Methods and Findings

We evaluated 90 studies from a total of 1,780 selected from the databases. 47 (52%) studies were CUAs incorporated into randomised clinical trials; 23 (26%) were health-state utility assessments; 8 (9%) validated methods and 12 (13%) compared existing or new methods. 22 unique direct or indirect calculation methods were used a total of 137 times. Direct calculation through standard gamble, time trade-off and visual analogue scale was used 32 times. The EuroQol EQ-5D was the most frequently-used single method, selected for 41 studies. 15 of the methods used were generic methods and the remaining 7 were disease-specific. 48 of the 90 studies (53%) used some form of proxy, with 26 (29%) using proxies exclusively to estimate health utilities.

Conclusions

Several child- and adolescent-specific methods are still being developed and validated, leaving many studies using methods that have not been designed or validated for use in children or adolescents. Several studies failed to justify using proxy respondents rather than administering the methods directly to the patients. Only two studies examined missing responses to the methods administered with respect to the patients’ ages.

Magnesium in man: implications for health and disease

Magnesium (Mg(2+)) is an essential ion to the human body, playing an instrumental role in supporting and sustaining health and life. As the second most abundant intracellular cation after potassium, it is involved in over 600 enzymatic reactions including energy metabolism and protein synthesis. Although Mg(2+) availability has been proven to be disturbed during several clinical situations, serum Mg(2+) values are not generally determined in patients. This review aims to provide an overview of the function of Mg(2+) in human health and disease. In short, Mg(2+) plays an important physiological role particularly in the brain, heart, and skeletal muscles. Moreover, Mg(2+) supplementation has been shown to be beneficial in treatment of, among others, preeclampsia, migraine, depression, coronary artery disease, and asthma. Over the last decade, several hereditary forms of hypomagnesemia have been deciphered, including mutations in transient receptor potential melastatin type 6 (TRPM6), claudin 16, and cyclin M2 (CNNM2). Recently, mutations in Mg(2+) transporter 1 (MagT1) were linked to T-cell deficiency underlining the important role of Mg(2+) in cell viability. Moreover, hypomagnesemia can be the consequence of the use of certain types of drugs, such as diuretics, epidermal growth factor receptor inhibitors, calcineurin inhibitors, and proton pump inhibitors. This review provides an extensive and comprehensive overview of Mg(2+) research over the last few decades, focusing on the regulation of Mg(2+) homeostasis in the intestine, kidney, and bone and disturbances which may result in hypomagnesemia.

Anesthesia and ventilation strategies in children with asthma: part II - intraoperative management

PURPOSE OF REVIEW

As asthma is a frequent disease especially in children, anesthetists are increasingly providing anesthesia for children requiring elective surgery with well controlled asthma but also for those requiring urgent surgery with poorly controlled or undiagnosed asthma. This second part of this two-part review details the medical and ventilatory management throughout the perioperative period in general but also includes the perioperative management of acute bronchospasm and asthma exacerbations in children with asthma.

RECENT FINDINGS

Multiple observational trials assessing perioperative respiratory adverse events in healthy and asthmatic children provide the basis for identifying risk reduction strategies. Mainly, animal experiments and to a small extent clinical data have advanced our understanding of how anesthetic agents effect bronchial smooth muscle tone and blunt reflex bronchoconstriction. Asthma treatment outside anesthesia is well founded on a large body of evidence.Perioperative prevention strategies have increasingly been studied. However, evidence on the perioperative management, including mechanical ventilation strategies of asthmatic children, is still only fair, and further research is required.

SUMMARY

To minimize the considerable risk of perioperative respiratory adverse events in asthmatic children, perioperative management should be based on two main pillars: the preoperative optimization of asthma treatment (please refer to the first part of this two-part review) and - the focus of this second part of this review - the optimization of anesthesia management in order to optimize lung function and minimize bronchial hyperreactivity in the perioperative period.

Magnesium should be given to all children presenting to hospital with acute severe asthma

Asthma is one of the most prevalent chronic condition affecting children worldwide and acute exacerbations requiring emergency medical management are common. In addition to corticosteroids, a number of drugs may be used in the management of acute severe asthma aiming to reverse bronchoconstriction. Magnesium sulphate - either inhaled or intravenous - may be added to conventional therapy of children with acute severe asthma. Despite its safety profile and effectiveness, the use of magnesium sulphate has been inconsistent due to lack of consensus. The authors believe that the accumulating evidence of a favorable 'cost benefit' profile justifies the use of magnesium for all children presenting with acute severe asthma.

Economic evaluation of nebulized magnesium sulphate in acute severe asthma in children

OBJECTIVES

The aim of this study was to estimate the cost-effectiveness of nebulized magnesium sulphate (MgSO4) in acute asthma in children from the perspective of the UK National Health Service and personal social services.

METHODS

An economic evaluation was conducted based on evidence from a randomized placebo controlled multi-center trial of nebulized MgSO4 in severe acute asthma in children. Participants comprised 508 children aged 2-16 years presenting to an emergency department or a children's assessment unit with severe acute asthma across thirty hospitals in the United Kingdom. Children were randomly allocated to receive nebulized salbutamol and ipratropium bromide mixed with either 2.5 ml of isotonic MgSO4 or 2.5 ml of isotonic saline on three occasions at 20-min intervals. Cost-effectiveness outcomes were constructed around the Yung Asthma Severity Score (ASS) after 60 min of treatment; whilst cost-utility outcomes were constructed around the quality-adjusted life-year (QALY) metric. The nonparametric bootstrap method was used to present cost-effectiveness acceptability curves at alternative cost-effectiveness thresholds for either: (i) a unit reduction in ASS; or (ii) an additional QALY.

RESULTS

MgSO4 had a 75.1 percent probability of being cost-effective at a GBP 1,000 (EUR 1,148) per unit decrement in ASS threshold, an 88.0 percent probability of being more effective (in terms of reducing the ASS) and a 36.6 percent probability of being less costly. MgSO4 also had a 67.6 percent probability of being cost-effective at a GBP 20,000 (EUR 22,957) per QALY gained threshold, an 8.5 percent probability of being more effective (in terms of generating increased QALYs) and a 69.1 percent probability of being less costly. Sensitivity analyses showed that the results of the economic evaluation were particularly sensitive to the methods used for QALY estimation.

CONCLUSIONS

The probability of cost-effectiveness of nebulized isotonic MgSO4, given as an adjuvant to standard treatment of severe acute asthma in children, is less than 70 percent across accepted cost-effectiveness thresholds for an additional QALY.

A review of the use of adjunctive therapies in severe acute asthma exacerbation in critically ill children

Asthma is a common and potentially life threatening childhood condition. Asthma involves not only chronic airway remodeling, but may also include frequent exacerbations resulting from bronchospasm, edema, and mucus production. In children with severe exacerbations, standard therapy with β2-agonists, anti-cholinergic agents, oxygen, and systemic steroids may fail to reverse the severe airflow obstruction and necessitate use of adjunctive therapies. These therapies include intravenous or inhaled magnesium, inhaled helium-oxygen mixtures, intravenous methylxanthines, intravenous β2-agonists, and intravenous ketamine. Rarely, these measures are not successful and following the initiation of invasive mechanical ventilation, inhaled anesthetics or extracorporeal life support may be required. In this review, we discuss the mechanisms and evidence for adjunctive therapies in the setting of severe acute asthma exacerbations in children.