Theophylline versus terbutaline in treating critically ill children with status asthmaticus: a prospective, randomized, controlled trial

[Diagnosis and treatment of asthma: a guideline for respiratory specialists 2023 - published by the German Respiratory Society (DGP) e. V.]

The management of asthma has fundamentally changed during the past decades. The present guideline for the diagnosis and treatment of asthma was developed for respiratory specialists who need detailed and evidence-based information on the new diagnostic and therapeutic options in asthma. The guideline shows the new role of biomarkers, especially blood eosinophils and fractional exhaled NO (FeNO), in diagnostic algorithms of asthma. Of note, this guideline is the first worldwide to announce symptom prevention and asthma remission as the ultimate goals of asthma treatment, which can be achieved by using individually tailored, disease-modifying anti-asthmatic drugs such as inhaled steroids, allergen immunotherapy or biologics. In addition, the central role of the treatment of comorbidities is emphasized. Finally, the document addresses several challenges in asthma management, including asthma treatment during pregnancy, treatment of severe asthma or the diagnosis and treatment of work-related asthma.

Recent Practice Patterns and Variations in Children Hospitalized for Asthma Exacerbation in Japan

BACKGROUND

High antibiotic prescribing rates for adults with an asthma exacerbation have been reported in developed countries, but few studies have assessed the variation of antibiotic and adjunctive treatment in the routine care of children.

OBJECTIVE

We evaluated the trends in health resource utilization for children hospitalized for asthma exacerbation, ascertained the variations of practices across hospitals and geographic location, and classified these different patterns at hospital levels.

METHODS

Using data on Japanese children hospitalized for asthma exacerbation with no indication of bacterial infection during 2010-2018, we conducted a retrospective observational study to assess the trends in initial treatment patterns and their variations. Mixed-effect generalized linear models were used to investigate the treatment trends. Hierarchical cluster analyses were performed to classify the treatment variations across hospitals.

RESULTS

Overall, 54,981 children were eligible for the study. Proportions of antibiotic use decreased from 47.2% in 2010 to 26.9% in 2018. Similarly, utilization of antitussives, antihistamines, and methylxanthine showed decreasing trends over the period, whereas the use of mucolytics and ambroxol increased. These treatment variations were more considerable in hospital levels than in 47 prefecture levels. Hierarchical cluster analyses classified these patterns into 6 groups, mostly based on mediator release inhibitor, ambroxol, and antitussives.

CONCLUSIONS

Wide variations in antibiotics and adjunctive treatments were observed across hospital levels. Our findings support the improvement in reducing inappropriate antibiotic use and highlight the need for comparative effectiveness research of the adjunctive treatments among children hospitalized for asthma.

Extracorporeal and advanced therapies for progressive refractory near-fatal acute severe asthma in children

Asthma is the most common chronic illness and is one of the most common medical emergencies in children. Progressive refractory near-fatal asthma requiring intubation and mechanical ventilation can lead to death. Extracorporeal membrane oxygenation (ECMO) can provide adequate gas exchange during acute respiratory failure although data on outcomes in children requiring ECMO support for status asthmaticus is sparse with one study reporting survival rates of nearly 85% with asthma being one of the best outcome subsets for patients with refractory respiratory failure requiring ECMO support. We describe the current literature on the use of ECMO and other advanced extracorporeal therapies available for children with acute severe asthma. We also review other advanced invasive and noninvasive therapies in acute severe asthma both before and while on ECMO support.

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.

TRIAL REGISTRATION NUMBER

CRD42017055331.

Efficacy and side effects of intravenous theophylline in acute asthma: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

Theophylline has been used for decades to treat both acute and chronic asthma. Despite its longevity in the practitioner's formulary, no detailed meta-analysis has been performed to determine the conditions, including concomitant medications, under which theophylline should be used for acute exacerbations of asthma. We aimed to quantify the usefulness and side effects of theophylline with or without ethylene diamine (aminophylline) in acute asthma, with particular emphasis on patient subgroups, such as children, adults, and concomitant medications.

METHODS

We searched PubMed, EMBASE, The Cochrane Library, ClinicalTrials.gov, and the WHO Clinical Trials Registry for randomized, controlled clinical trials. We planned a priori subgroup analyses by time post-medication, concomitant medication, control type, and age.

RESULTS

We included 52 study arms from 42 individual trials. Of these, 29 study arms included an active control, such as adrenaline, beta-2 agonists, or leukotriene receptor antagonists, and 23 study arms compared theophylline (with or without ethylene diamine) with placebo or no drug. Theophylline significantly reduced heart rate when compared with active control (p=0.01) and overall duration of stay (p=0.002), but beta-2 agonists were superior to theophylline at improving forced expiratory volume in one second (FEV1) (p=0.002). Theophylline was not significantly different from other drugs in its effects on respiratory rate, forced vital capacity (FVC), peak expiratory flow rate, admission rate, use of rescue medication, oxygen saturation, or symptom score. Closer examination of the data revealed that the medications given in addition to theophylline or control significantly changed the effectiveness of theophylline (subgroup difference: p<0.00001).

CONCLUSION

Given the low cost of theophylline, and its similar efficacy and rate of side effects compared with other drugs, we suggest that theophylline, when given with bronchodilators with or without steroids, is a cost-effective and safe choice for acute asthma exacerbations.

Anti-inflammatory dosing of theophylline in the treatment of status asthmaticus in children

BACKGROUND

Low-dose theophylline has been recognized for its ability to restore histone deacetylase-2 activity which leads to improved steroid responsiveness and thus improved clinical outcome. We retrospectively evaluated the effect of low-dose theophylline therapy in pediatric patients hospitalized for an acute asthma exacerbation as a proof of concept study.

METHODS

We compared patients who received low-dose theophylline (5-7 mg/kg/day) in addition to current standard of care to patients who were treated with current standard of care alone. The primary outcome of the study was hospital length of stay (LOS). Generalized linear mixed-effects modeling (GLMM) was used to test whether receiving theophylline independently predicted outcomes. A Cox (proportional hazards) regression model was also developed to examine whether theophylline impacted LOS.

RESULTS

After adjustment for illness severity measures, theophylline significantly reduces LOS (β=-21.17, P<0.001), time to discontinue oxygen (β=-15.88, P=0.044), time to spirometric improvement (β=-16.60, P=0.014), and time to space albuterol (β=-23.2, P<0.001) as well as reduced costs (β=-US$2,746, P<0.001). Furthermore, theophylline significantly increased the hazards of being discharged from the hospital (hazards ratio =1.75, 95% confidence interval 1.20-2.54, P=0.004). There was no difference in side effects between patients who receive low-dose theophylline and those who did not.

CONCLUSION

The results of this retrospective study suggest low-dose theophylline may have a positive effect in acute status asthmaticus. This study suggests that further research with a prospective, randomized, double-blinded, placebo controlled trial may be warranted to confirm and extend our findings.

Aminophylline Dosage In Asthma Exacerbations in Children: A Systematic Review

BACKGROUND

Adequate asthma treatment of childhood exacerbations with IV aminophylline depends on appropriate dosage. Recommendations to aim for a target therapeutic range may be inappropriate as serum concentrations correlate poorly with clinical improvement. This review aims to evaluate the evidence for the optimum dosage strategy of intravenous aminophylline in children suffering an exacerbation of asthma.

METHODS

A systematic review comparing dosage regimens of intravenous aminophylline in children suffering an exacerbation of asthma. Primary outcomes were time until resolution of symptoms, mortality and need for mechanical ventilation. Secondary outcomes were date until discharge criteria are met, actual discharge and adverse effects.

DATA SOURCES

CENTRAL, CINAHL, MEDLINE and Web of Science. Search performed in March 2016.

ELIGIBILITY CRITERIA

Studies using intravenous aminophylline in children with an acute exacerbation of asthma which reported the dosage and clinical outcomes.

FINDINGS

14 RCTs were included. There is a poor relationship between the dosage administered to children and symptom resolution, length of stay or need for mechanical ventilation. This study is limited due to its use of indirect evidence.

CONCLUSION

The currently recommended dosage regimens may not represent the optimum safety and efficacy of intravenous aminophylline. There is a need to develop the evidence base correlating dosage with patient centered clinical outcomes, to improve prescribing practices.

Novel relaxant effects of RPL554 on guinea pig tracheal smooth muscle contractility

BACKGROUND AND PURPOSE

We investigated the effectiveness of RPL554, a dual PDE3 and 4 enzyme inhibitor, on airway smooth muscle relaxation and compared it with that induced by salbutamol, ipratropium bromide, glycopyrrolate or their combination on bronchomotor tone induced by different spasmogenic agents.

EXPERIMENTAL APPROACH

Guinea pig tracheal preparations were suspended under 1 g tension in Krebs-Henseleit solution maintained at 37°C and aerated with 95% O2 /5% CO2 and incubated in the presence of indomethacin (5 μM). Relaxation induced by cumulative concentrations of muscarinic receptor antagonists (ipratropium bromide or glycopyrrolate), β2 -adrenoceptor agonists (salbutamol or formoterol), PDE3 inhibitors (cilostamide, cilostazol or siguazodan) or a PDE4 inhibitor (roflumilast) was evaluated in comparison with RPL554. Maximal relaxation was calculated (% Emax papaverine) and expressed as mean ± SEM.

KEY RESULTS

Bronchomotor tone induced by the various spasmogens was reduced by the different bronchodilators to varying degrees. RPL554 (10-300 μM) caused near maximum relaxation irrespective of the spasmogen examined, whereas the efficacy of the other relaxant agents varied according to the contractile stimulus used. During the evaluation of potential synergistic interactions between bronchodilators, RPL554 proved superior to salbutamol when either was combined with muscarinic receptor antagonists.

CONCLUSIONS AND IMPLICATIONS

RPL554 produced near maximal relaxation of highly contracted respiratory smooth muscle and provided additional relaxation compared with that produced by other clinically used bronchodilator drugs. This suggests that RPL554 has the potential to produce additional beneficial bronchodilation over and above that of maximal clinical doses of standard bronchodilators in highly constricted airways of patients.

Asthma-related emergency department use: current perspectives

Asthma is one of the most common chronic pediatric diseases. Patients with asthma often present to the emergency department for treatment for acute exacerbations. These patients may not have a primary care physician or primary care home, and thus are seeking care in the emergency department. Asthma care in the emergency department is multifaceted to treat asthma patients appropriately and provide quality care. National and international guidelines exist to help drive clinical care. Electronic and paper-based tools exist for both physicians and patients to help improve emergency, home, and preventive care. Treatment of patients with asthma should include the acute exacerbation, long-term management of controller medications, and controlling triggers in the home environment. We will address the current state of asthma research in emergency medicine in the US, and discuss some of the resources being used to help provide a medical home and improve care for patients who suffer from acute asthma exacerbations.

Asthma changes at a pediatric intensive care unit after 10 years: Observational study

OBJECTIVES:

To describe the change in the management, and outcome of children with acute severe asthma (ASA) admitted to Pediatric Intensive Care Unit (PICU) at tertiary institute, as compared to previously published report in 2003.

METHODS:

This is a retrospective observational study. All consecutive pediatric ASA patients who were admitted to PICU during the study period were included. The data were extracted from PICU database and medical records. The Cohort in this study (2013 Cohort) was compared with the Cohort of ASA, which was published in 2003 from the same institution (2003 Cohort).

RESULTS:

In comparison to previous 2003 Cohort, current Cohort (2013) revealed higher mean age (5.5 vs. 3.6 years; P ≤ 0.001), higher rate of PICU admission (20.3% vs. 3.6%; P ≤ 0.007), less patients who received maintenance inhaled steroids (43.3% vs. 62.4%; P ≤ 0.03), less patients with pH <7.3 (17.9% vs. 42.9%; P ≤ 0.001). There were more patients in 2013 Cohort who received: Inhaled Ipratropium bromide (97% vs. 68%; P ≤ 0.001), intravenous magnesium sulfate (68.2% vs. none), intravenous salbutamol (13.6% vs. 3.6%; P ≤ 0.015), and noninvasive ventilation (NIV) (35.8% vs. none) while no patients were treated with theophylline (none vs. 62.5%). The median length of stay (LOS) was 2 days while mean LOS was half a day longer in the 2013 Cohort. None of our patients required intubation, and there was no mortality.

CONCLUSION:

We observed slight shift toward older age, considerably increased the rate of PICU admission, increased utilization of Ipratropium bromide, magnesium sulfate, and NIV as important modalities of treatment.

Pharmacotherapy of critical asthma syndrome: current and emerging therapies

The critical asthma syndrome (CAS) encompasses the most severe, persistent, refractory asthma patients for the clinician to manage. Personalized pharmacotherapy is necessary to prevent the next acute severe asthma exacerbation, not just the control of symptoms. The 2007 National Asthma Education and Prevention Program Expert Panel 3 provides guidelines for the treatment of uncontrolled asthma. The patient's response to recommended pharmacotherapy is highly variable which risks poor asthma control leading to frequent exacerbations that can deteriorate into CAS. Controlling asthma symptoms and preventing acute exacerbations may be two separate clinical activities with their own unique demands. Clinicians must be prepared to use the entire spectrum of asthma medications available but must concurrently be aware of potential drug toxicities some of which can paradoxically worsen asthma control. Medications normally prescribed for COPD can potentially be useful in the CAS patient, particularly those with asthma-COPD overlap syndrome. Immunomodulation with drugs like omalizumab in IgE-mediated asthma syndromes is one important approach. New and emerging drugs address unique aspects of airway inflammation and biology but at a significant financial cost. The pharmacology and toxicities of the agents that may be used in the treatment of CAS to control asthma symptoms and prevent severe exacerbations are reviewed.

The acute management of asthma

Patients presenting to the emergency department (ED) or clinic with acute exacerbation of asthma (AEA) can be very challenging varying in both severity and response to therapy. High-dose, frequent or continuous nebulized short-acting beta2 agonist (SABA) therapy that can be combined with a short-acting muscarinic antagonist (SAMA) is the backbone of treatment. When patients do not rapidly clinically respond to SABA/SAMA inhalation, the early use of oral or parenteral corticosteroids should be considered and has been shown to impact the immediate need for ICU admission or even the need for hospital admission. Adjunctive therapies such as the use of intravenous magnesium and helium/oxygen combination gas for inhalation and for driving a nebulizer to deliver a SABA and or SAMA should be considered and are best used early in the treatment plan if they are likely to impact the patients' clinical course. The use of other agents such as theophylline, leukotriene modifiers, inhaled corticosteroids, long-acting beta2 agonist, and long-acting muscarinic antagonist currently does not play a major role in the immediate treatment of AEA in the clinic or the ED but is an important therapeutic option for physicians to be aware of and to consider initiating at the time of discharge from clinic, hospital, or ED to reduce later clinical worsening and readmission to the ED and hospital. A comprehensive summary is provided of the currently available respiratory pharmaceuticals approved for asthma and other airway syndromes. Clinicians must be prepared to use the entire spectrum of medications available for the treatment of acute asthma exacerbations and the agents that should be initiated to prevent worsening or additional exacerbations. They need to be familiar with the major potential drug toxicities associated with their use.

Volatile anesthetics for status asthmaticus in pediatric patients: a comprehensive review and case series

Status asthmaticus is an acute, intractable asthma attack refractory to standard interventions that can lead to progressive respiratory failure. Successful management requires a fundamental understanding of the disease process, its clinical presentation, and proper evaluation. Treatment must be instituted early and is aimed at reversing the airway inflammation, bronchoconstriction, and hyper-reactivity that often lead to lower airway obstruction, impaired ventilation, and oxygenation. Most patients are effectively treated with standard therapy including beta2-adrenergic agonists and corticosteroids. Others necessitate adjunctive therapies and escalation to noninvasive ventilation or intubation. We will review the pathophysiology, evaluation, and treatment options for pediatric patients presenting with status asthmaticus with a particular focus on refractory status asthmaticus treated with volatile anesthetics. In addition, we include a proven approach to the management of these patients in the critical care setting, which requires close coordination between critical care and anesthesia providers. We present a case series of three patients, two of which have the longest reported cases of continuous isoflurane use in status asthmaticus. This series was obtained from a retrospective chart review and highlights the efficacy of the volatile anesthetic, isoflurane, in three pediatric patients with refractory life-threatening status asthmaticus.

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.

Severe acute asthma exacerbation in children: a stepwise approach for escalating therapy in a pediatric intensive care unit

OBJECTIVES

An increasing prevalence of pediatric asthma has led to increasing burdens of critical illness in children with severe acute asthma exacerbations, often leading to respiratory distress, progressive hypoxia, and respiratory failure. We review the definitions, epidemiology, pathophysiology, and clinical manifestations of severe acute asthma, with a view to developing an evidence-based, stepwise approach for escalating therapy in these patients.

METHODS

Subject headings related to asthma, status asthmaticus, critical asthma, and drug therapy were used in a MEDLINE search (1980-2012), supplemented by a manual search of personal files, references cited in the reviewed articles, and treatment algorithms developed within Le Bonheur Children's Hospital.

RESULTS

Patients with asthma require continuous monitoring of their cardiorespiratory status via noninvasive or invasive devices, with serial clinical examinations, objective scoring of asthma severity (using an objective pediatric asthma score), and appropriate diagnostic tests. All patients are treated with β-agonists, ipratropium, and steroids (intravenous preferable over oral preparations). Patients with worsening clinical status should be progressively treated with continuous β-agonists, intravenous magnesium, helium-oxygen mixtures, intravenous terbutaline and/or aminophylline, coupled with high-flow oxygen and non-invasive ventilation to limit the work of breathing, hypoxemia, and possibly hypercarbia. Sedation with low-dose ketamine (with or without benzodiazepines) infusions may allow better toleration of non-invasive ventilation and may also prepare the patient for tracheal intubation and mechanical ventilation, if indicated by a worsening clinical status.

CONCLUSIONS

Severe asthma can be a devastating illness in children, but most patients can be managed by using serial objective assessments and the stepwise clinical approach outlined herein. Following multidisciplinary education and training, this approach was successfully implemented in a tertiary-care, metropolitan children's hospital.

Management of status asthmaticus in children

Recent literature on paediatric status asthmaticus (PSA) confirms an increasing percentage of admissions to paediatric intensive care units. PSA is a medical emergency that can be fatal and needs careful and prompt intervention. The severity of PSA is mainly determined by clinical judgement of signs and symptoms. Peak flow measurements and serial lung function measurements are not reliable in PSA. Validated clinically useful instruments are lacking. The three main factors that are involved in the pathophysiology of PSA, bronchoconstriction, mucus plugging and airway inflammation need to be addressed to optimise treatment. Initial therapies include supplementation of oxygen, repetitive administration of rapid acting β2-agonists, inhaled anticholinergics in combination with systemic glucocorticosteroids and intravenous magnesium sulphate. Additional treatment modalities may include methylxanthines, DNase, ketamine, sodium bicarbonate, heliox, epinephrine, non-invasive respiratory support, mechanical ventilation and inhalational anaesthetics.

Acute asthma exacerbations in childhood: risk factors, prevention and treatment

Asthma is a heterogeneous disease more appropriately seen as a syndrome rather than a single pathologic entity. Although it can remain quiescent for extended time periods, the inflammatory and remodeling processes affect the bronchial milieu and predispose to acute and occasionally severe clinical manifestations. The complexity underlying these episodes is enhanced during childhood, an era of ongoing alterations and maturation of key biological systems. In this review, the authors focus on such sudden-onset events, emphasizing on their diversity on the basis of the numerous asthma phenotypes.

Anaesthetic management of the child with co-existing pulmonary disease

Children with co-existing pulmonary disease have a wide range of clinical manifestations with significant implications for anaesthetists. Although there are a number of pulmonary diseases in children, this review focuses on two of the most common pulmonary disorders, asthma and bronchopulmonary dysplasia (BPD). These diseases share the physiology of bronchoconstriction and variably decreased flow in the airways, but also have unique physiological consequences. The anaesthetist can make a difference in outcomes with proper preoperative evaluation and appropriate preparation for surgery in the context of a team approach to perioperative care with implementation of a stepwise approach to disease management. An understanding of the importance of minimizing the risk for bronchoconstriction and having the tools at hand to treat it when necessary is paramount in the care of these patients. Unique challenges exist in the management of pulmonary hypertension in BPD patients. This review covers medical treatment, intraoperative management, and postoperative care for both patient populations.

Addition of intravenous beta(2)-agonists to inhaled beta(2)-agonists for acute asthma

BACKGROUND

Inhaled beta-agonist therapy is central to the management of acute asthma. This review evaluates the benefit of an additional use of intravenous beta(2)-agonist agents.

OBJECTIVES

To determine the benefit of adding intravenous (IV) beta(2)-agonists to inhaled beta(2)-agonist therapy for acute asthma treated in the emergency department.

SEARCH METHODS

Randomised controlled trials (RCTs) were identified using the Cochrane Airways Group Register which is a compilation of systematic searches of MEDLINE, EMBASE, CINAHL, and CENTRAL as well as handsearching of 20 respiratory journals. Bibliographies from included studies and known reviews were also searched. Primary authors and content experts were contacted to identify eligible studies. The search was performed in September 2012.

SELECTION CRITERIA

Only RCTs were considered for inclusion. Studies were included if patients presented to the emergency department with acute asthma and were treated with IV beta(2)-agonists with inhaled beta(2)-agonist therapy and existing standard treatments versus inhaled beta(2)-agonists and existing standard treatments.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and confirmed their findings with corresponding authors of trials. We obtained missing data from authors or calculated from data present in the papers. We used fixed-effect model for odds ratios (OR) and for mean differences (MD) we used both fixed-effect and random-effects models and reported 95% confidence intervals (CI).

MAIN RESULTS

From 109 potentially relevant studies only three (104 patients) met our inclusion criteria: Bogie 2007 (46 children), Browne 1997 (29 children) and Nowak 2010 (29 adults). Bogie 2007 investigated the addition of intravenous terbutaline to high dose nebulised albuterol in children with acute severe asthma, requiring intensive care unit (ICU) admission. Browne 1997 investigated the benefit of adding intravenous salbutamol to inhaled salbutamol in children with acute severe asthma in the emergency department. Nowak 2010 investigated addition of IV bedoradrine to standard care (nebulised albuterol, ipratropium and oral corticosteroids) among adults, and was reported as a conference abstract only.There was no significant advantage (OR 0.29; 95%CI 0.06 to 1.38, one trial, 29 adults) for adding IV bedoradrine to standard care (nebulised albuterol, ipratropium and oral corticosteroids) with regard to hospitalisation rates.Various outcome indicators for the length of stay were reported among the trials. Browne 1997 reported a significantly shorter recovery time (in terms of cessation of 30 minute salbutamol) for children in the IV salbutamol with inhaled salbutamol group (four hours) versus the 11.1 hours for the inhaled salbutamol group (P = 0.03). Time to cessation of hourly nebuliser was also significantly shorter (P = 0.02) for the IV plus inhaled salbutamol group (11.5 hours versus 21.2 hours), and they were ready for emergency patient discharge on average 9.7 hours earlier than the inhaled salbutamol group (P < 0.05). In a paediatric ICU study Bogie 2007 reported no significant advantage in length of paediatric ICU admission (hours) for adding IV terbutaline to nebulised albuterol (MD -12.95, 95% CI: -38.74, 12.84).Browne 1997 reported there were only six out of 14 children with a pulmonary index score above six in the IV plus inhaled salbutamol group at two hours compared with 14 of the 15 in the inhaled salbutamol group (P = 0.02)In Browne 1997 there was a higher proportion of tremor in the IV plus inhaled salbutamol group than in the inhaled salbutamol group (P < 0.02). Nowak 2010 did not report any statistically significant adverse effects associated with adding IV bedoradrine to standard care (nebulised albuterol, ipratropium and oral corticosteroids). Troponin levels were elevated in three children in the IV terbutaline + nebulised albuterol group at 12 and 24 hours in Bogie 2007

AUTHORS' CONCLUSIONS

There is very limited evidence from one study (Browne 1997) to support the use of IV beta(2)-agonists in children with severe acute asthma with respect to shorter recovery time, and similarly there is limited evidence (again from one study Browne 1997) suggesting benefit with regard to pulmonary index scores; however this advantage needs to be considered carefully in relation to the increased side effects associated with IV beta(2)-agonists. We identified no significant benefits for adults with severe acute asthma. Until more, adequately powered, high quality clinical trials in this area are conducted it is not possible to form a robust evaluation of the addition of IV beta(2)-agonists in children or adults with severe acute asthma.

Intravenous beta(2)-agonists versus intravenous aminophylline for acute asthma

BACKGROUND

Inhaled beta(2)-agonist therapy is central to the management of acute asthma. For rapid bronchodilation in severe cases, penetration of inhaled drug to the affected small conducting airway may be impeded, and the intravenous (IV) rather than inhaled administration of bronchodilators may provide an earlier response. IV beta(2)-agonist agents and IV aminophylline may also be considered as additional interventions in this setting and this review compares IV beta-agonist agents and IV aminophylline in the treatment of people with acute asthma.

OBJECTIVES

To compare the benefit of IV beta(2)-agonists versus IV aminophylline for acute asthma treated in the emergency department and in patients admitted to hospital with acute severe asthma.

SEARCH METHODS

Randomised controlled trials (RCTs) were identified using the Cochrane Airways Group Register, which is compiled from systematic searches of bibliographic databases as well as handsearching of respiratory journals and conference abstracts. The latest search was run in September 2012. We searched bibliographies from included studies and known reviews were also searched. Primary authors and content experts were contacted to identify eligible studies.

SELECTION CRITERIA

We included RCTs of patients who presented to the emergency department with acute asthma, and patients admitted to hospital with acute severe asthma, and were treated with IV beta(2)-agonists versus IV aminophylline. Two review authors independently selected potentially relevant articles and selected articles for inclusion. Methodological quality was independently assessed using two scoring systems and two review authors.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by two review authors. Missing data were obtained from authors or calculated from data present in the papers. Trials were combined using a random-effects model for odds ratios (OR) or mean differences (MD) and reported with 95% confidence intervals (95% CI).

MAIN RESULTS

Eleven studies met our inclusion criteria and in total they included 350 patients. However, opportunities to combine these studies in meta-analyses were limited by the variations in the range of outcomes reported in the trials.Length of stayTwo studies reported length of stay. They were both paediatric trials (with one in paediatric intensive care unit), and there was no significant difference between the two groups (MD 23.19 hours; 95% CI -2.40 to 48.77 hours; 2 studies; N = 73). Individual separate MD analyses for the two studies also indicated no significant difference between the aminophylline and beta(2)-agonist on this outcome. However, this finding should be interpreted with caution owing to the small number of trials and participants the analysis.Pulmonary functionThere were no significant differences in the sequential or summative pulmonary function demonstrated across the studies.Heart rateData for serial heart rates were reported in three studies at various points from 15 to 60 minutes and in each case there were no significant differences between people in the IV aminophylline or beta(2)-agonist groups. The difference between the two groups with respect to final heart rate was statistically significant (MD 10.00; 95% CI 0.99 to 19.01), although these data are from a single, small study and should be interpreted with caution.Adverse effectsThe analyses for giddiness (OR 59.22; 95% CI 2.80 to 1253.05; 1 study; N = 30), nausea/vomiting (where reported as a combined outcome) (OR 14.18; 95% CI 1.62 to 124.52; 2 studies; N = 96) and nausea (OR 6.53; 95% CI 1.60 to 26.72; 2 studies; N = 49) all significantly favoured beta(2)-agonists. In view of the very small number of studies and number of patients contributing to these analyses these results should be interpreted with caution. A closely related review considering the possible benefits of adding IV aminophylline to beta-agonists in adults with acute asthma also indicates a higher incidence of adverse effects associated with IV aminophylline.

AUTHORS' CONCLUSIONS

In the included RCTs there was no consistent evidence favouring either IV beta(2)-agonists or IV aminophylline for patients with acute asthma. The opportunity to draw clear conclusions is limited by the heterogeneity of outcomes evaluated and the small sample sizes in the included studies. It is recommended that these data should be viewed carefully alongside the conclusions from separate Cochrane reviews comparing IV beta(2)-agonists plus inhaled beta(2)-agonists versus inhaled beta(2)-agonists alone and IV aminophylline plus inhaled beta(2)-agonists versus inhaled beta(2)-agonists alone.

Fatal and near-fatal asthma in children: the critical care perspective

OBJECTIVE

To characterize the clinical course, therapies, and outcomes of children with fatal and near-fatal asthma admitted to pediatric intensive care units (PICUs).

STUDY DESIGN

This was a retrospective chart abstraction across the 8 tertiary care PICUs of the Collaborative Pediatric Critical Care Research Network (CPCCRN). Inclusion criteria were children (aged 1-18 years) admitted between 2005 and 2009 (inclusive) for asthma who received ventilation (near-fatal) or died (fatal). Data collected included medications, ventilator strategies, concomitant therapies, demographic information, and risk variables.

RESULTS

Of the 261 eligible children, 33 (13%) had no previous history of asthma, 218 (84%) survived with no known complications, and 32 (12%) had complications. Eleven (4%) died, 10 of whom had experienced cardiac arrest before admission. Patients intubated outside the PICU had a shorter duration of ventilation (median, 25 hours vs 84 hours; P < .001). African-Americans were disproportionately represented among the intubated children and had a shorter duration of intubation. Barotrauma occurred in 15 children (6%) before admission. Pharmacologic therapy was highly variable, with similar outcomes.

CONCLUSION

Of the children ventilated in the CPCCRN PICUs, 96% survived to hospital discharge. Most of the children who died experienced cardiac arrest before admission. Intubation outside the PICU was correlated with shorter duration of ventilation. Complications of barotrauma and neuromyopathy were uncommon. Practice patterns varied widely among the CPCCRN sites.

Bronchiolite e asma

La letteratura internazionale ha recentemente riconosciuto la mancanza di confini netti fra bronchiolite (BR), wheezing (WH), o respiro sibilante, e asma.

Acute bronchial asthma

Acute asthma is the third commonest cause of pediatric emergency visits at PGIMER. Typically, it presents with acute onset respiratory distress and wheeze in a patient with past or family history of similar episodes. The severity of the acute episode of asthma is judged clinically and categorized as mild, moderate and severe. The initial therapy consists of oxygen, inhaled beta-2 agonists (salbutamol or terbutaline), inhaled budesonide (three doses over 1 h, at 20 min interval) in all and ipratropium bromide and systemic steroids (hydrocortisone or methylprednisolone) in acute severe asthma. Other causes of acute onset wheeze and breathing difficulty such as pneumonia, foreign body, cardiac failure etc. should be ruled out with help of chest radiography and appropriate laboratory investigations in first time wheezers and those not responding to 1 h of inhaled therapy. In case of inadequate response or worsening, intravenous infusion of magnesium sulphate, terbutaline or aminophylline may be used. Magnesium sulphate is the safest and most effective alternative among these. Severe cases may need ICU care and rarely, ventilatory support.

Management of severe asthma exacerbation in children

BACKGROUND

Asthma is a common disease in children and acute severe asthma exacerbation can be life-threatening. This article aims to review recent advances in understanding of risk factors, pathophysiology, diagnosis and treatment of severe asthma exacerbation in children.

DATA SOURCES

Articles concerning severe asthma exacerbation in children were retrieved from PubMed. Literatures were searched with MeSH words "asthma", "children", "severe asthma exacerbation" and relevant cross references.

RESULTS

Severe asthma exacerbation in children requires aggressive treatments with β2-agonists, anticholinergics, and corticosteroids. Early initiation of inhaled β-agonists and systemic use of steroids are recommended. Other agents such as magnesium and aminophylline have some therapeutic benefits. When intubation and mechanical ventilation are needed, low tidal volume, controlled hypoventilation with lower-than-traditional respiratory rates and permissive hypercapnia can be applied.

CONCLUSIONS

Researchers should continue to detect the risk factors, pathophysiology, diagnosis and treatment of severe asthma exacerbation in children. More studies especially randomized controlled trials are required to evaluate the efficacy and safety of standard and new therapies.

Trends in admissions for pediatric status asthmaticus in New Jersey over a 15-year period

OBJECTIVE

Status asthmaticus accounts for a large portion of the morbidity and mortality associated with asthma, but we know little about its epidemiology. We describe here the hospitalization characteristics of children with status asthmaticus, how they changed over time, and how they differed between hospitals with and without PICUs.

PATIENTS AND METHODS

We used administrative data from New Jersey that included all hospitalizations in the state from 1992, 1995, and 1999-2006. We identified children with status asthmaticus by using International Classification of Diseases, Ninth Revision, diagnosis codes that indicate status asthmaticus and the use of mechanical ventilation by using procedure codes. We designated hospitals with a PICU as "PICU hospitals" and those without as "adult hospitals."

RESULTS

We identified 28 309 admissions of children with status asthmaticus (22.8% of all asthma hospitalizations). From 1992 to 2006, the rate of hospital admissions decreased by half (from 1.98 in 1000 to 0.93 in 1000 children), and there was a 70% decrease in the number of children admitted to adult hospitals. The rate of ICU care in PICU hospitals more than tripled. However, the rate of mechanical ventilation remained low, and the number of deaths was small and unchanged (n=14 total). Hospital costs climbed from $6.6 million to $9.5 million.

CONCLUSIONS

Although fewer children are being admitted with status asthmaticus, the proportion of patients managed in PICUs is climbing. There has been no substantial change in rates of mechanical ventilation or death. Additional research is needed to better understand how patients and physicians decide on the appropriate site for hospital care and how that choice affects outcome.

A retrospective characterization of African- and European American asthmatic children in a pediatric critical care unit

OBJECTIVE

To determine if African American and European American children with asthma admitted to an intensive care unit (ICU) had different characteristics, we conducted a retrospective chart review of asthma admissions to the region's only pediatric ICU.

PATIENTS AND METHODS

A chart review was performed on 125 patients with asthma admitted to the pediatric critical care unit at Vanderbilt Children's Hospital. Descriptive statistics, clinical characteristics, and disparities in care were compared using either Fisher's exact tests or Wilcoxon ranksum tests.

RESULTS

Most of the children reported previous admissions to a pediatric ICU (63%) or a hospital (82%) for asthma. Despite this, only 48% of the children were taking inhaled corticosteroids before admission. Only 28% of the children reported being followed by an asthma specialist, but, of these, 97% were taking corticosteroids. There were no racial/ethnic disparities in medication use, treatment, or outcomes.

CONCLUSION

We found no racial/ethnic disparities in inpatient/outpatient medication usage, treatment, or outcomes between African American and European American children in our cohort. Recurrent admissions to the ICU among children with severe asthma are common, and inhaled corticosteroids usage is relatively low. Asthmatic children with ICU admissions should be followed and treated aggressively by an asthma specialist.

Emergency presentation and management of acute severe asthma in children

Acute severe asthma is one of the most common medical emergency situations in childhood, and physicians caring for acutely ill children are regularly faced with this condition. In this article we present a summary of the pathophysiology as well as guidelines for the treatment of acute severe asthma in children. The cornerstones of the management of acute asthma in children are rapid administration of oxygen, inhalations with bronchodilators and systemic corticosteroids. Inhaled bronchodilators may include selective b2-agonists, adrenaline and anticholinergics. Additional treatment in selected cases may involve intravenous administration of theophylline, b2-agonists and magnesium sulphate. Both non-invasive and invasive ventilation may be options when medical treatment fails to prevent respiratory failure. It is important that relevant treatment algorithms exist, applicable to all levels of the treatment chain and reflecting local considerations and circumstances.

Slow-responders to IV beta2-adrenergic agonist therapy: defining a novel phenotype in pediatric asthma

OBJECTIVES

While aerosolized administration of beta(2)-adrenergic receptor (beta(2)-AR) agonists is the mainstay of treatment for pediatric asthma exacerbations, the efficacy of intravenous (IV) delivery is controversial. Failure to demonstrate improved outcomes with IV beta(2)-AR agonists may be due to phenotypic differences within this patient population. Our hypothesis is that children who respond more slowly to IV beta(2)-AR agonist therapy comprise a distinct phenotype.

METHODS

Retrospective chart review of all children admitted to the ICU for status asthmaticus who were treated with IV terbutaline between December 2002 and September 2006.

RESULTS

Seventy-eight children were treated with IV terbutaline according to guidelines that adjusted the dose by clinical asthma score. After examining the histogram of duration of terbutaline infusions, a 48-hr cutoff was chosen to define responsiveness. Thirty-eight (49%) children were slow-responders by this definition. There were no significant differences in baseline asthma severity or severity on admission between the slow-responders and responders. Slow-responders required significantly higher total doses of IV terbutaline, higher maximum administration rates, and had longer ICU and hospital length of stay.

CONCLUSION

There were significant differences in outcomes between the responders and slow-responders without differences in acute or chronic illness severity. Other factors may have lead to slower response to IV beta(2)-agonist therapy.

Status asthmaticus in children

PURPOSE OF REVIEW

The prevalence of severe asthma in children has risen in the past few decades. The present review explores our current understanding of epidemiology, pathophysiology and treatment of status asthmaticus in children.

RECENT FINDINGS

The pathophysiology of inflammation and airway hyperactivity continues to be a source of research. Early initiation of inhaled beta-agonists and oral or parenteral steroids remain the standard of care in the treatment of status asthmaticus. Other treatment modalities such as magnesium and intravenous beta-agonists show some benefit. There is a resurgence of interest in the use of methylxanthines. Alternatives to endotracheal intubation show some promise in preventing respiratory failure.

SUMMARY

Asthma remains the third leading cause of hospitalization in children younger than 15 years old. Researchers continue to explore the efficacy of old and new treatment modalities. Future research efforts targeting at-risk populations could dramatically decrease asthma morbidity and mortality.

Comparison of intravenous terbutaline versus normal saline in pediatric patients on continuous high-dose nebulized albuterol for status asthmaticus

OBJECTIVE

To determine if the addition of intravenous terbutaline provides any clinical benefit to children with acute severe asthma already on continuous high-dose nebulized albuterol.

METHODS

We conducted a prospective, randomized, double blind, placebo-controlled trial on pediatric patients with acute severe asthma presenting to a large inner city tertiary children's emergency department. Consecutive patients between 2 and 17 years of age who failed acute asthma management and needed intensive care unit admission underwent informed consent and were enrolled into the study. Patients not requiring intubation were randomized to receive either intravenous terbutaline or intravenous normal saline while on continuous high-dose nebulized albuterol, ipratropium bromide, and systemic corticosteroids. Outcome measures included a clinical asthma severity score, hours on continuous nebulized albuterol, and duration of stay in the pediatric intensive care unit. In addition, electrocardiograms, electrolytes, lactic acid, and troponin I levels were obtained at routine intervals during the first 24 hours after admission. Patients who significantly worsened while enrolled in the study received intravenous aminophylline according to protocol.

RESULTS

Forty-nine patients were enrolled in the study. Patients on terbutaline had a mean improvement in the clinical asthma severity score over the first 24 hours of 6.5 points compared with 4.8 points in the placebo group (P = 0.073). Patients on terbutaline spent 38.19 hours on continuous nebulized albuterol compared with their placebo counterparts who spent 51.93 hours (P = 0.25). The length of stay in the PICU was on average 12.95 hours longer for those patients in the placebo group as compared with the terbutaline group (P = 0.345). One patient was removed from the study for a significant cardiac dysrhythmia. This patient was in the terbutaline group and recovered without complications. Troponin I values at 12 hours and 24 hours were elevated in 3 patients each, all within the terbutaline group.

CONCLUSIONS

No outcome measures demonstrated statistical significance. Outcome measures revealed a trend toward improvement in the terbutaline group. Before recommending routine use of intravenous terbutaline for acute severe asthma, further study to determine safety and efficacy is necessary.