Near-fatal asthma: recognition and management

Near fatal asthma in a case of allergic bronchopulmonary aspergillosis (ABPA) treated with ECMO

BACKGROUND

Fatal asthma is a rapidly progressing and highly fatal form of asthma. Mechanical ventilation, although necessary for respiratory support, can exacerbate the condition and lead to ventilator-associated lung injury. ECMO therapy is crucial in allowing the lungs to rest and recover, as it provides extracorporeal membrane oxygenation.

CASE PRESENTATION

A 40-year-old man presented with dyspnea following a mountain climb, which rapidly worsened, leading to respiratory failure and loss of consciousness. Despite drug therapy and mechanical ventilation, arterial blood gas analysis showed persistent hypercapnia. After 3 days of ECMO support, the patient was successfully extubated and underwent treatment for Aspergillus infection. Chest CT returned to normal after 3 months of anti-aspergillus therapy.

CONCLUSION

When drug therapy and mechanical ventilation fail to improve respiratory failure in fatal asthma, prompt initiation of ECMO support is essential to create opportunities for subsequent etiological treatment.

Extracorporeal membrane oxygenation for near fatal asthma with sudden cardiac arrest

INTRODUCTION

Near fatal asthma is a life-threatening disorder that requires mechanical ventilation. Near fatal asthma and COPD with sudden cardiac arrest can worsen the outcomes. Previous studies demonstrated that ECMO is a live-saving measure for near fatal asthma that does not respond to traditional treatment.

CASE STUDY

A patient with near fatal asthma (NFA) and COPD presented with high airway resistance, life-threatening acidemia and severe hypoxemia that failed to respond to conventional therapy. His hospital course was complicated by sudden cardiac arrest when preparing to initiate V-V mode extracorporeal membrane oxygenation (ECMO). The mode immediately changed from V-V to V-A, then to V-AV and finally to V-V mode in order to improve cardiac function and promote recovery of lung function.

RESULTS

On the sixth day, ECMO was removed and on the ninth day, he was extubated and transferred to the ward. Finally, the patient was discharged home on the nineteenth day after admission to be followed up in the pulmonary clinic.

CONCLUSIONS

The early application of ECMO and mode changing plausibly resulted in dramatic improvement in gas exchange and restoration of cardiac function. This case illustrates the critical role of ECMO mode changing as salvage therapy in NFA and COPD with sudden cardiac arrest.

A territory-wide study on the factors associated with recurrent asthma exacerbations requiring hospitalization in Hong Kong

Background

The real‐world relationships between the demographic and clinical characteristics of asthma patients, their prehospitalization management and the frequency of hospitalization due to asthma exacerbation is poorly established.

Objective

To determine the risk factors of recurrent asthma exacerbations requiring hospitalizations and evaluate the standard of baseline asthma care.

Methods

A territory‐wide, multicentre retrospective study in Hong Kong was performed. Medical records of patients aged ≥18 years admitted to 11 acute general hospitals from January 1 to December 31, 2016 for asthma exacerbations were reviewed.

Results

There were 2280 patients with 3154 admissions (36.7% male, median age 66.0 [interquartile range: 48.0–81.0] years, 519 had ≥2 admissions). Among them, 1830 (80.3%) had at least one asthma‐associated comorbidity, 1060 (46.5%) and 885 (38.9%) of patients had Accident and Emergency Department (AED) attendance and hospitalization in the preceding year, respectively. Patients with advancing age (incidence rate ratio [IRR]: 1.003 for every year increment), a history of AED visits or hospitalization (IRR: 1.018 and 1.070 for every additional episode, respectively) for asthma exacerbation in the preceding year, the presence of neuropsychiatric (IRR: 1.142) and gastrointestinal (IRR: 1.154) comorbidities were risk factors for an increasing number of admissions for asthma exacerbation. For patients with ≥2 admissions, 17.1% were not prescribed inhaled corticosteroid and only 44.6% had spirometry checked before the index admission. Asthma phenotyping was often incomplete, as assessment of atopy (total serum immunoglobulin E level and senitization to aeroallergens) was only performed in 30 (5.8%) patients with ≥2 admissions.

Conclusions and Clinical Relevance

Improving asthma care, especially in elderly patients with a prior history of urgent healthcare utilization and comorbidities, may help reduce healthcare burden. Suboptimal management before the index admission was common in patients hospitalized for asthma exacerbations. Early identification of patients at risk and enhancement of baseline asthma management may help to prevent recurrent asthma exacerbation and subsequent hospitalization.

Biologics and global burden of asthma: A worldwide portrait and a call for action

Biologics for severe asthma can significantly impact on the burden of disease and also have the potential to reduce asthma mortality. By reviewing the literature and contacting the pharmaceutical companies, the present paper aims at providing a worldwide snapshot of biologic drugs availability, related with the trend of asthma mortality rate, as a marker of the burden of the disease. A decline in the global rate of annual asthma mortality was observed until the 1980s, but overall no further reduction occurred, and the current mortality estimation is 0.19 deaths per 100.000 people. A higher mortality rate has been registered in low and middle-income countries (LMICs), where poor socioeconomic conditions and lack of access to the medical resources are more relevant. The availability of monoclonal antibodies is mainly limited to the developed and high-income countries. Furthermore the overall "asthma management system" in LMICs suffers from a number of restrictions that hamper the widespread availability of biologics besides their costs. The availability of generic drugs in the field of biologics for severe asthma could contribute to facilitate their widespread accessibility. But before that, awareness and expertise regarding severe asthma, and proper tools to assess and manage it, deserve to be shared worldwide. Collaboration projects involving physicians from all the countries through the scientific Academies network and with the support of the Companies active in the field may provide an initial concrete opportunity.

Evaluation and management of the critically ill adult asthmatic in the emergency department setting

INTRODUCTION

Asthma is a common reason for presentation to the Emergency Department and is associated with significant morbidity and mortality. While patients may have a relatively benign course, there is a subset of patients who present in a critical state and require emergent management.

OBJECTIVE

This narrative review provides evidence-based recommendations for the assessment and management of patients with severe asthma.

DISCUSSION

It is important to consider a broad differential diagnosis for the cause and potential mimics of asthma exacerbation. Once the diagnosis is determined, the majority of the assessment is based upon the clinical examination. First line therapies for severe exacerbations include inhaled short-acting beta agonists, inhaled anticholinergics, intravenous steroids, and magnesium. Additional therapies for refractory cases include parenteral epinephrine or terbutaline, helium‑oxygen mixture, and consideration of ketamine. Intravenous fluids should be administered, as many of these patients are dehydrated and at risk for hypotension if they receive positive pressure ventilatory support. Noninvasive positive pressure ventilation may prevent the need for endotracheal intubation. If mechanical ventilation is required, it is important to avoid breath stacking by setting a low respiratory rate and allowing permissive hypercapnia. Patients with severe asthma exacerbations will require intensive care unit admission.

CONCLUSIONS

This review provides evidence-based recommendations for the assessment and management of severe asthma with a focus on the emergency clinician.

Total Unilateral Lung Atelectasis in a Child with Asthma and Its Rapid Resolution with Medical Management without Any Invasive Intervention: A Case Report

Asthma is the most common chronic lung condition of childhood affecting approximately 6 million children in the United States. Right middle lobe syndrome or atelectasis is common in children with asthma though whole unilateral lung collapse is rare; only case series are reported. Bronchoscopy is usually required in addition to medical management of asthma and treatment of infection. We present a case of unilateral lung atelectasis in a young child which resolved with intense medical management without any endoscopy.

Immune responses in fatalities involving opioids

In some cases of fatalities involving opioid use, the concentrations of detected opioids are not in the toxic range. Immune reactions can be triggered by opioid use, suggesting that immune response may be a factor in these cases. Autopsy cases from 2002–2012 were reviewed. Persons with physical, microscopic or serum evidence of allergic reactions and opioid use at autopsy were compared to persons who used opioids but had no such signs. Overall, 49 persons were identified who had used opioids, of which five had evidence of immune response. A medical history of asthma was significantly more common in persons with signs of immune response (P = 0.0244) and fatality (P = 0.0085) compared to normals. A history of asthma is suggestive of susceptibility to immunologic reactions to opioids, and correlates strongly with the cause of death.

The anatomic substrate of irreversible airway obstruction and barotrauma in a case of hurricane-triggered fatal status asthmaticus during puerperium: Lessons from an autopsy

Non-fully reversible airway obstruction in fatal asthma is often seen in association with profound structural changes of the bronchial wall, termed airway remodeling. Evidence suggests that heavy precipitation events can trigger epidemics of severe asthma. We present a case of fatal asthma in a young woman with no prior near-fatal exacerbations and postulate that the patient's extensive airway remodeling and puerperal state (susceptibility factors), in combination with a massive allergen challenge during a hurricane landfall (triggering factor), played a central role in her death. The autopsy revealed diffuse obstruction of proximal and distal bronchi by mucous plugs together with transmural chronic inflammation, tissue eosinophilia, extensive goblet cell hyperplasia with MUC-5 expression and airway smooth muscle (ASM) thickening. The observed distribution of airway remodeling was heterogeneous with sparing of the lingula, which exhibited hyperinflation and expansion of perivascular spaces indicative of dissecting air. The massive stagnation of mucus and significant inter-airway structural heterogeneity created an anatomical substrate for unequal airflow distribution facilitating the development of barotrauma. Although not considered conventional risk factors for fatal asthma, we believe that in this case, the patient's puerperal state in conjunction with an extreme environmental event dispersing aeroallergens were major contributors to the development of a fatal asthma attack. Our autopsy findings suggest that effective strategies to evacuate stagnated mucus and induce relaxation of thickened ASM are crucial in the management of life-threatening asthma exacerbations.

Extracorporeal membrane oxygenation for life-threatening asthma refractory to mechanical ventilation: analysis of the Extracorporeal Life Support Organization registry

Background

The use of extracorporeal membrane oxygenation (ECMO) in cases of near-fatal asthma (NFA) has increased, but the benefits and potential complications of this therapy have yet to be fully investigated.

Methods

Cases were extracted from the Extracorporeal Life Support Organization Registry between March 1992 and March 2016. All patients with a diagnosis of asthma (according to the International Classification of Diseases 9th edition), who also received ECMO, were extracted. Exclusion criteria included patients who underwent multiple courses of ECMO; those who received ECMO for cardiopulmonary resuscitation or cardiac dysfunction; and those with another primary diagnosis, such as sepsis. We analyzed survival to hospital discharge, complications, and clinical factors associated with in-hospital mortality, in patients with severe life-threatening NFA requiring ECMO support.

Results

In total 272 patients were included. The mean time spent on ECMO was 176.4 hours. Ventilator settings, including rate, fraction of inspired oxygen (FiO₂), peak inspiratory pressure (PIP), and mean airway pressure, significantly improved after ECMO initiation (rate (breaths/min), 19.0 vs. 11.3, p < 0.001; FiO₂ (%), 81.2 vs. 48.8, p < 0.001; PIP (cmH₂O), 38.2 vs. 25.0, p < 0.001; mean airway pressure (cmH₂O): 21.4 vs. 14.2, p < 0.001). In particular, driving pressure was significantly decreased after ECMO support (29.5 vs. 16.8 cmH₂O, p < 0.001). The weaning success rate was 86.7%, and the rate of survival to hospital discharge was 83.5%. The total complication rate was 65.1%, with hemorrhagic complications being the most common (28.3%). Other complications included renal (26.8%), cardiovascular (26.1%), mechanical (24.6%), metabolic (22.4%), infection (16.5%), neurologic (4.8%), and limb ischemia (2.6%). Of the hemorrhagic complications, cannulation site hemorrhage was the most common (13.6%). Using multivariate logistic regression analysis, it was found that hemorrhage was associated with increased in-hospital mortality (odds ratio, 2.97; 95% confidence interval, 1.07–8.24; p = 0.036). Hemorrhage-induced death occurred in four patients (1.5%). The most common reason for death was organ failure (37.8%).

Conclusions

ECMO can provide adequate gas exchange and prevent lung injury induced by mechanical ventilation, and may be an effective bridging strategy to avoid aggressive ventilation in refractory NFA. However, careful management is required to avoid complications.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-017-1886-8) contains supplementary material, which is available to authorized users.

Acute Asthma in the Pediatric Emergency Department: Infections Are the Main Triggers of Exacerbations

Background

Asthma exacerbations are a common reason for Emergency Department (ED) visits in children.

Aim

To analyze differences among age groups in terms of triggering factors and seasonality and to identify those with higher risk of severe exacerbations.

Methods

We retrospectively revised the files of children admitted for acute asthma in 2016 in our Pediatric ED.

Results

Visits for acute asthma were 603/23197 (2.6%). 76% of the patients were <6 years old and 24% ≥6. Infections were the main trigger of exacerbations in both groups; 33% of the school-aged children had a triggering allergic condition (versus 3% in <6 years; p < .01). 191 patients had a previous history of asthma; among them, 95 were ≥6 years, 67% of whom were not using any controller medication, showing a higher risk of a moderate-to-severe exacerbation than those under long-term therapy (p < .01). Exacerbations peaked in autumn and winter in preschoolers and in spring and early autumn in the school-aged children.

Conclusions

Infections are the main trigger of acute asthma in children of any age, followed by allergy in the school-aged children. Efforts for an improved management of patients affected by chronic asthma might go through individualized action plans and possibly vaccinations and allergen-avoidance measures.

"Awake" ECCO2R superseded intubation in a near-fatal asthma attack

BACKGROUND

Near-fatal asthma attacks are life threatening events that often require mechanical ventilation. Extracorporeal carbon dioxide removal (ECCO₂R) is, beside extracorporeal membrane oxygenation (ECMO), a well-established rescue option whenever ventilation gets to its limits. But there seems to be very rare experience with those techniques in avoiding mechanical ventilation in severe asthma attacks.

CASE PRESENTATION

A 67-year-old man with a near-fatal asthma attack deteriorated under non-invasive ventilation conditions. Beside pharmacological treatment, the intensivists decided to use an extracorporeal carbon dioxide removal system (ECCO₂R) to avoid sedation and intubation. Within only a few hours, there was a breakthrough and the patient's status improved continuously. One and a half days later, weaning from ECCO₂R was already completed.

CONCLUSIONS

The discussion deals with several advantages of extracorporeal lung support in acute asthma, the potential of avoiding intubation and sedation, as well as the benefits of a conscious and spontaneously breathing patient. Extracorporeal membrane oxygenation (ECMO) in general and ECCO₂R in particular is a highly effective method for the treatment of an acute near-fatal asthma attack. Pathophysiological aspects favor the "awake" approach, without sedation, intubation, and mechanical ventilation. Therefore, experienced clinicians might consider "awake" ECCO₂R in similar cases.

Reslizumab in the treatment of inadequately controlled asthma in adults and adolescents with elevated blood eosinophils: clinical trial evidence and future prospects

Eosinophils have long been implicated as playing a central role in the pathophysiology of asthma in many patients, and eosinophilic asthma is now recognized as an important asthma endotype. Eosinophil differentiation, maturation, migration, and survival are primarily under the control of interleukin-5 (IL-5). Reslizumab is a humanized monoclonal (immunoglobulin G4/κ) antibody that binds with high affinity to circulating human IL-5 and downregulates the IL-5 signaling pathway, potentially disrupting the maturation and survival of eosinophils. In 2016, an intravenous formulation of reslizumab was approved in the USA, Canada, and Europe as add-on maintenance treatment for patients aged ⩾18 years with severe asthma and with an eosinophilic phenotype. The efficacy of reslizumab as add-on intravenous therapy has been reported in several phase III studies in patients with inadequately controlled moderate-to-severe asthma and elevated blood eosinophil counts (⩾400 cells/µl). Compared with placebo, reslizumab was associated with significant improvements in clinical exacerbation rate, forced expiratory volume in 1 s, asthma symptoms and quality of life, and significant reductions in blood eosinophil counts. Reslizumab also demonstrated a favorable tolerability profile similar to that of placebo, with reported adverse events being mostly mild to moderate in severity. Ongoing studies are focusing on the evaluation of a subcutaneous formulation of reslizumab in patients with asthma and elevated eosinophil levels. This review discusses the preclinical and clinical trial data available on reslizumab, potential opportunities for predicting an early response to reslizumab, and future directions in the field of anti-IL-5 antibody therapy.

Near Fatal Asthma in an Inner City Population

Near-fatal asthma (NFA) is highly prevalent in inner city population. Patients who present with NFA require timely intervention, which necessitates knowledge of appropriate associated risk factors. The purpose of the study was to look and identify the salient features of an asthma exacerbation that are more likely to be associated with NFA in inner city population. We conducted a retrospective analysis of patients who were discharged from the hospital with a diagnosis of acute asthma exacerbation. Two hundred eighteen patients were included in the study. Patients who required intubation during the course of their hospitalization were defined as NFA and the rest were defined as non-near-fatal asthma (NNFA). Multiple patient parameters were compared between the 2 groups; 60 patients met the definition of NFA. There was no difference between NFA and NNFA groups with respect to sex, race, and history of smoking and asthma treatment modalities before presentation. NFA was seen more commonly in heroin (40% vs. 25.9%; P < 0.05) and cocaine users (28.3% vs. 16.5%; P < 0.05). A history of exacerbation requiring intensive care unit (ICU) care was more common among the NFA patients (55% vs. 40.5%; P = 0.05). A history of intubation for an exacerbation was more commonly seen in patients presenting with NFA (51.7% vs. 35.4%; P < 0.05). The NNFA group was more likely to have a primary care physician and to be discharged home (65.6% vs. 51.7%, P < 0.05; and 71.7 vs. 79.1%, P < 0.05). In a multi-logistic regression model, including age, sex, race, heroin and cocaine use, history of intubation and ICU admission, medications, use of noninvasive ventilation, primary care physician, and pH <7.35, PCO2 >45 mm Hg, and FiO2 >40% on initial blood gas, NFA was predicted only by PaCO2 >45 [odds ratio (OR = 6.7; P < 0.001)] and FiO2 >40% (OR = 3.5; P = 0.002). Use of noninvasive ventilation was a negative predictor of NFA (OR = 0.2; P < 0.001). Asthmatic patients who carry a history of intubation with mechanical ventilation for an asthma exacerbation, admissions to the ICU, or those who indulge in recreational drugs like cocaine or heroin should be closely monitored for clinical deterioration.

Extracorporeal membrane oxygenation support for life-threatening acute severe status asthmaticus

INTRODUCTION

Status asthmaticus is a life-threatening condition characterized by progressive respiratory failure due to asthma that is unresponsive to standard therapeutic measures. We used extracorporeal membrane oxygenation (ECMO) to treat patients with near-fatal status asthamticus who did not respond to aggressive medical therapies and mechanical ventilation under controlled permissive hypercapnia.

MATERIALS AND METHODS

Between January 2011 and October 2015, we treated 16 adult patients with status asthmaticus (8 women, 8 men, mean age: 50.5±10.6years) with veno-venous ECMO (13 patients) or veno-arterial (3 patients). Patients failed to respond to conventional therapies despite receiving the most aggressive therapies, including maximal medical treatments, mechanical ventilation under controlled permissive hypercapnia and general anesthetics.

RESULTS

Mean time spent on ECMO was 300±11.8 hours (range 36-384 hours). PaO2, PaCO2 and pH showed significant improvement promptly after ECMO initiation p=0.014, 0.001 and <0.001, respectively, and such values remained significantly improved after ECMO, p=0.004 and 0.001 and <0.001, respectively. The mean time of ventilation after decannulation until extubation was 175±145.66 hours and the median time to intensive care unit discharge after decannulation was 234±110.30 hours. All 16 patients survived without neurological sequelae.

CONCLUSIONS

ECMO could provide adjunctive pulmonary support for intubated asthmatic patients who remain severely acidotic and hypercarbic despite aggressive conventional therapy. ECMO should be considered as an early treatment in patients with status asthmaticus whose gas exchange cannot be satisfactorily maintained by conventional therapy for providing adequate gas change and preventing lung injury from the ventilation.

Monoclonal antibody therapy for the treatment of asthma and chronic obstructive pulmonary disease with eosinophilic inflammation

Eosinophils have been linked with asthma for more than a century, but their role has been unclear. This review discusses the roles of eosinophils in asthma and chronic obstructive pulmonary disease (COPD) and describes therapeutic antibodies that affect eosinophilia. The aims of pharmacologic treatments for pulmonary conditions are to reduce symptoms, slow decline or improve lung function, and reduce the frequency and severity of exacerbations. Inhaled corticosteroids (ICS) are important in managing symptoms and exacerbations in asthma and COPD. However, control with these agents is often suboptimal, especially for patients with severe disease. Recently, new biologics that target eosinophilic inflammation, used as adjunctive therapy to corticosteroids, have proven beneficial and support a pivotal role for eosinophils in the pathology of asthma. Nucala® (mepolizumab; anti-interleukin [IL]-5) and Cinquair® (reslizumab; anti-IL-5), the second and third biologics approved, respectively, for the treatment of asthma, exemplifies these new treatment options. Emerging evidence suggests that eosinophils may contribute to exacerbations and possibly to lung function decline for a subset of patients with COPD. Here we describe the pharmacology of therapeutic antibodies inhibiting IL-5 or targeting the IL-5 receptor, as well as other cytokines contributing to eosinophilic inflammation. We discuss their roles as adjuncts to conventional therapeutic approaches, especially ICS therapy, when disease is suboptimally controlled. These agents have achieved a place in the therapeutic armamentarium for asthma and COPD and will deepen our understanding of the pathogenic role of eosinophils.

Asthma-related deaths

Despite major advances in the treatment of asthma and the development of several asthma guidelines, people still die of asthma currently. According to WHO estimates, approximately 250,000 people die prematurely each year from asthma. Trends of asthma mortality rates vary very widely across countries, age and ethnic groups. Several risk factors have been associated with asthma mortality, including a history of near-fatal asthma requiring intubation and mechanical ventilation, hospitalization or emergency care visit for asthma in the past year, currently using or having recently stopped using oral corticosteroids (a marker of event severity), not currently using inhaled corticosteroids, a history of psychiatric disease or psychosocial problems, poor adherence with asthma medications and/or poor adherence with (or lack of) a written asthma action plan, food allergy in a patient with asthma. Preventable factors have been identified in the majority of asthma deaths. Inadequate education of patients on recognising risk and the appropriate action needed when asthma control is poor, deficiencies in the accuracy and timing of asthma diagnosis, inadequate classification of severity and treatment, seem to play a part in the majority of asthma deaths. Improvements in management, epitomized by the use of guided self-management systems of care may be the key goals in reducing asthma mortality worldwide.

Epidemiology and Pulmonary Physiology of Severe Asthma

The epidemiology and physiology of severe asthma are inherently linked because of varying phenotypes and expressions of asthma throughout the population. To understand how to better treat severe asthma, we must use both population data and physiologic principles to individualize therapies among groups with similar expressions of this disease.

Pediatric acute asthma exacerbations: Evaluation and management from emergency department to intensive care unit

OBJECTIVE

The goal of this report is to review available modalities for assessing and managing acute asthma exacerbations in pediatric patients, including some that are not included in current expert panel guidelines. While it is not our purpose to provide a comprehensive review of the National Asthma Education and Prevention Program (NAEPP) guidelines, we review NAEPP-recommended treatments to provide the full range of treatments available for managing exacerbations with an emphasis on the continuum of care between the ER and ICU.

DATA SOURCES

We searched PubMed using the following search terms in different combinations: asthma, children, pediatric, exacerbation, epidemiology, pathophysiology, guidelines, treatment, management, oxygen, albuterol, β2-agonist, anticholinergic, theophylline, corticosteroid, magnesium, heliox, BiPAP, ventilation, mechanical ventilation, non-invasive mechanical ventilation and respiratory failure. We attempted to weigh the evidence using the hierarchy in which meta-analyses of randomized controlled trials (RCTs) provide the strongest evidence, followed by individual RCTs, followed by observational studies. We also reviewed the NAEPP and Global Initiative for Asthma expert panel guidelines.

RESULTS AND CONCLUSIONS

Asthma is the most common chronic disease of childhood, and acute exacerbations are a significant burden to patients and to public health. Optimal assessment and management of exacerbations, including appropriate escalation of interventions, are essential to minimize morbidity and prevent mortality. While inhaled albuterol and systemic corticosteroids are the mainstay of exacerbation management, escalation may include interventions discussed in this review.

Benralizumab: a unique IL-5 inhibitor for severe asthma

The presence of eosinophilic inflammation is a characteristic feature of chronic and acute inflammation in asthma. An estimated 5%–10% of the 300 million people worldwide who suffer from asthma have a severe form. Patients with eosinophilic airway inflammation represent approximately 40%–60% of this severe asthmatic population. This form of asthma is often uncontrolled, marked by refractoriness to standard therapy, and shows persistent airway eosinophilia despite glucocorticoid therapy. This paper reviews personalized novel therapies, more specifically benralizumab, a humanized anti-IL-5Rα antibody, while also being the first to provide an algorithm for potential candidates who may benefit from anti-IL-5Rα therapy.

A case of near fatal asthma: The role of ECMO as rescue therapy

We report a case of an adolescent with near fatal asthma (NFA). He presented with severe hypoxemia and lifethreatening acidemia, who failed to respond to conventional therapy. His hospital course was complicated by barotrauma and hemodynamic instability. Early introduction of extracorporeal membrane oxygenation (ECMO) led to dramatic improvement in gas exchange and lung mechanics. This case illustrates the important role of ECMO as salvage therapy in NFA.

Cervical lung herniation complicating a case of acute asphyxial asthma in a child

The abrupt onset of respiratory failure secondary to asthma, known as acute asphyxial asthma (AAA) in adults, is uncommonly reported in children. Here, we report a case of a child with the acute onset of respiratory failure consistent with AAA complicated by the finding of a neck mass during resuscitation. This 11-year-old boy with a history of asthma initially presented in respiratory failure with altered mental status after the complaint of difficulty in breathing minutes before collapsing at home. Initially, his respiratory failure was thought to be secondary to status asthmaticus, and treatment was initiated accordingly. However, a neck mass noted during the resuscitation was cause for concern, and other etiologies for his respiratory failure were considered, including an airway obstructing neck mass. After pediatric surgery and anesthesia consultation for intubation and possible tracheostomy placement, general anesthesia was induced in the operating room with an inhaled anesthetic, with prompt resolution of the bronchspasm and decompression of the neck mass. Review of the imaging and clinical course ultimately yielded a diagnosis of cervical lung herniation as the etiology of his neck mass. We report this case of AAA and cervical lung herniation and a review of the literature of these 2 uncommon phenomena in children.

A randomized trial of benralizumab, an antiinterleukin 5 receptor α monoclonal antibody, after acute asthma

BACKGROUND

Patients with frequent asthma exacerbations resulting in emergency department (ED) visits are at increased risk for future exacerbations. We examined the ability of 1 dose of benralizumab, an investigational antiinterleukin 5 receptor α monoclonal antibody, to reduce recurrence after acute asthma exacerbations.

METHODS

In this randomized, double-blind, placebo-controlled study, eligible subjects presented to the ED with an asthma exacerbation, had partial response to treatment, and greater than or equal to 1 additional exacerbation within the previous year. Subjects received 1 intravenous infusion of placebo (n = 38) or benralizumab (0.3 mg/kg, n = 36 or 1.0 mg/kg, n = 36) added to outpatient management. The primary outcome was the proportion of subjects with greater than or equal to 1 exacerbation at 12 weeks in placebo vs the combined benralizumab groups. Other outcomes included the time-weighted rate of exacerbations at week 12, adverse events, blood eosinophil counts, asthma symptom changes, and health care resource utilization.

RESULTS

The proportion of subjects with greater than or equal to 1 asthma exacerbation at 12 weeks was not different between placebo and the combined benralizumab groups (38.9% vs 33.3%; P = .67). However, compared with placebo, benralizumab reduced asthma exacerbation rates by 49% (3.59 vs 1.82; P = .01) and exacerbations resulting in hospitalization by 60% (1.62 vs 0.65; P = .02) in the combined groups. Benralizumab reduced blood eosinophil counts but did not affect other outcomes, while demonstrating an acceptable safety profile.

CONCLUSIONS

When added to usual care, 1 dose of benralizumab reduced the rate and severity of exacerbations experienced over 12 weeks by subjects who presented to the ED with acute asthma.

Developments in the field of allergy in 2012 through the eyes of Clinical & Experimental Allergy

In 2012, we received 683 submissions and published 20 editorials, 38 reviews, 11 letters and 128 original articles. This represents an acceptance rate for original papers in the range of 20%. About 30% of original papers were triaged not to go out to review, either because the editors did not feel they had sufficient priority for publication or because the topic did not feel right for the readers of the journal. We place great emphasis on obtaining sufficient high-quality reviews to make our decisions on publication fair and consistent. Inevitably, however, there is a degree of luck about what gets published and which papers miss out, and we are always happy to receive an appeal on our decisions either at the triage stage or after review. This gives us the opportunity to revisit the decision and revise it or explain in more detail to the authors the basis for the decision. Once again in 2012, we were delighted by the quality of the papers submitted and the breadth and depth of research into allergic disease that it revealed. The pattern of papers submitted was similar in previous years with considerable emphasis on all aspects of asthma and rhinitis. We were particularly pleased with our special issue on severe asthma. Elucidating mechanisms using either animal models or patients has always been a major theme of the journal, and the excellent work in these areas has been summarized by Harissios Vliagoftis with a particularly interesting section on early-life events guiding the development of allergic disease, which understandably continue to be a major theme of research. Magnus Wickman summarized the papers looking at the epidemiology of allergic disease including work from birth cohorts, which are an increasingly rich source of data on risk factors for allergic disease, and two papers on the epidemiology of anaphylaxis. Giovanni Passalacqua discussed the papers in the clinical allergy section of the journal, and Adriano Mari who runs the excellent Allergome website discussed the papers looking at allergens including characterization and the relative usefulness of allergen arrays versus single extracts in diagnosis and management.

Risk factors, management and outcomes of patients admitted with near fatal asthma to a tertiary care hospital in Riyadh

RATIONALE:

Near-fatal asthma (NFA) has not been well studied in Saudi Arabia. We evaluated NFA risk factors in asthmatics admitted to a tertiary-care hospital and described NFA management and outcomes.

MATERIALS AND METHODS:

This was a retrospective study of NFA patients admitted to an ICU in Riyadh (2006-2010). NFA was defined as a severe asthma attack requiring intubation. To evaluate NFA risk factors, randomly selected patients admitted to the ward for asthma exacerbation were used as controls. Collected data included demographics, information on prior asthma control and various NFA treatments and outcomes.

RESULTS:

Thirty NFA cases were admitted to the ICU in the five-year period. Compared to controls (N = 120), NFA patients were younger (37.5 ± 19.9 vs. 50.3 ± 23.1 years, P = 0.004) and predominantly males (70.0% vs. 41.7%, P = 0.005) and used less inhaled steroids/long-acting ß2-agonists combination (13.6% vs. 38.7% P = 0.024. Most (73.3%) NFA cases presented in the cool months (October-March). On multivariate analysis, age (odds ratio [OR] 0.96; 95% confidence interval [CI], 0.92-0.99, P = 0.015) and the number of ED visits in the preceding year (OR, 1.25; 95% CI, 1.00-1.55) were associated with NFA. Rescue NFA management included ketamine (50%) and theophylline (19%) infusions. NFA outcomes included: neuromyopathy (23%), mechanical ventilation duration = 6.4 ± 4.7 days, tracheostomy (13%) and mortality (0%). Neuromuscular blockade duration was associated with neuromyopathy (OR, 3.16 per one day increment; 95% CI, 1.27-7.83).

CONCLUSIONS:

In our study, NFA risk factors were younger age and higher number of ED visits. NFA had significant morbidity. Reducing neuromuscular blockade duration during ventilator management may decrease neuromyopathy risk.

Early administration of terbutaline in severe pediatric asthma may reduce incidence of acute respiratory failure

BACKGROUND

Severe pediatric asthma, if not immediately and aggressively treated, may progress to acute respiratory failure requiring mechanical ventilation in the pediatric intensive care unit (PICU). Intravenous (IV) terbutaline, a β2 agonist, is dispensed when the initial treatment does not improve the clinical condition.

OBJECTIVE

To investigate the influence of early initiation of IV terbutaline on the incidence of acute respiratory failure requiring mechanical ventilation in severe pediatric asthma.

METHODS

A retrospective chart review was conducted of 120 subjects (35 patients from an outside hospital emergency department [ED] with late start of terbutaline and 85 patients from the authors' hospital ED with early initiation of IV terbutaline) admitted to the PICU with severe asthma treated with continuous IV terbutaline. Responses to terbutaline treatment and outcomes were evaluated.

RESULTS

Patients transported from outlying hospital EDs had shorter pre-PICU mean durations of IV terbutaline than those transferred from the authors' ED (0.69 ± 1.38 and 2.91 ± 2.47 hours, respectively, P = .001). Twenty-one of 35 patients (60%) from outlying EDs required mechanical ventilation compared with 14 of 85 patients (16%) from the authors' ED (P = .001). Durations of pre-PICU terbutaline infusion for patients requiring mechanical ventilation were significantly shorter than those with no such requirement (P = .015).

CONCLUSION

The results of the present study, conducted in the largest number of subjects to date, suggest that early administration of continuous terbutaline in the ED may decrease acute respiratory failure and the need for mechanical respiratory (invasive and noninvasive) support in severe pediatric asthma.

Effects of feedback on the perception of inspiratory resistance in children with persistent asthma: a signal detection approach

OBJECTIVE

Accurate perception of asthma episodes increases the likelihood that they will be managed effectively. The purpose of the study was to examine the effect of feedback in a signal detection task on perception of increased airflow obstruction in children with persistent asthma.

METHODS

The effect of feedback training on the perception of resistive loads was evaluated in 155 children with persistent asthma between 8 and 15 years of age. Each child participated in four experimental sessions that occurred approximately once every 2 weeks, an initial session followed by three training sessions. During the initial session, the threshold resistance to breathing was determined for each child. Subsequently, each child was randomly assigned to one of two resistive load training conditions in a signal detection paradigm: training with immediate performance feedback or training with no performance feedback.

RESULTS

The threshold resistance to breathing, determined in the initial session, was equivalent between groups. Children in the feedback condition discriminated more accurately between both the presence and the absence of increases in the resistance to breathing (206 [48] versus 180 [39] correct responses, p < .001), and differences over time between groups increased reliably as a function of training (165 [40] versus 145 [32] correct responses, p < .001). Response times and confidence ratings were equivalent between groups, and no differences in breathing patterns were observed between conditions.

CONCLUSIONS

Feedback training results in improved perception of respiratory sensations in children with asthma, a finding with implications for strategies of asthma self-management.

Contemporary topics in pediatric pulmonology for the primary care clinician

Disorders of the respiratory system are commonly encountered in the primary care setting. The presentations are myriad and this review will discuss some of the more intriguing or vexing disorders that the clinician must evaluate and treat. Among these are dyspnea, chronic cough, chest pain, wheezing, and asthma. Dyspnea and chest pain have a spectrum ranging from benign to serious, and the ability to effectively form a differential diagnosis is critical for reassurance and treatment, along with decisions on when to refer for specialist evaluation. Chronic cough is one of the more common reasons for primary care office visits, and once again, a proper differential diagnosis is necessary to assist the clinician in formulating an appropriate treatment plan. Infant wheezing creates much anxiety for parents and accounts for a large number of office visits and hospital admissions. Common diagnoses and evaluation strategies of early childhood wheezing are reviewed. Asthma is one of the most common chronic diseases of children and adults. The epidemiology, diagnosis, evaluation, treatment, and the patient/parent education process will be reviewed. A relatively new topic for primary care clinicians is cystic fibrosis newborn screening. The rationale, methods, outcomes, and implications will be reviewed. This screening program may present some challenges for clinicians caring for newborns, and an understanding of the screening process will help the clinician communicate effectively with parents of the patient.

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.

Nebulised DNase post-therapeutic bronchoalveolar lavage in near fatal asthma exacerbation in an adult patient refractory to conventional treatment

Mucus plugging plays a vital role in the pathophysiology of fatal and near fatal asthma as demonstrated in various postmortem studies. There is a paucity of published literature on how to manage mucus plugging in adult patients with refractory asthma exacerbation not responding to conventional therapies as compared with its paediatric cohort. We describe a dramatic improvement with the use of rhDNase, following bronchoalveolar lavage in an intubated adult female patient, with status asthmaticus refractory to conventional treatment.

Demographics, clinical course, and outcomes of children with status asthmaticus treated in a pediatric intensive care unit: 8-year review

OBJECTIVE

This study was done to understand the demographics, clinical course, and outcomes of children with status asthmaticus treated in a tertiary care pediatric intensive care unit (PICU).

METHODS

The medical charts of all patients above 5 years of age admitted to the PICU at Nationwide Children's Hospital, Columbus, OH, USA, with status asthmaticus from 2000 to 2007 were reviewed retrospectively. Data from 222 encounters by 183 children were analyzed.

RESULTS

The mean age at admission in years was 11 ± 3.8. The median PICU stay was 1 day (range, 1-12 days) and median hospital stay was 3 days. The ventilated group (n = 17) stayed a median of 2 days longer in the PICU and hospital. Nearly half of the children (n = 91; 50%) did not receive daily controller asthma medications. Adherence to asthma medications was reported in 125 patient charts of whom 43 (34%) were compliant. Exposure to smoking was reported in 167 of whom 70 (42%) were exposed. Among patients receiving metered dose inhaler (MDI), only 39 (18%) were using it with a spacer. Among 105 patient charts asthma severity data were available, of them 21 (20%) were labeled as mild intermittent, 29 (28%) were mild persistent, 26 (25%) were moderate persistent, and 29 (28%) were severe persistent. Compared to children with only one PICU admission during the study period (n = 161), children who had multiple PICU admissions (n = 22) experienced more prior emergency department visits and hospitalizations for asthma symptoms. There were no fatalities.

CONCLUSION

Asthmatics with any disease severity are at risk for life-threatening asthma exacerbations requiring PICU stay, especially those who are not adherent with their daily medications.

Critical care in the ED: potentially fatal asthma and acute lung injury syndrome

Emergency department clinicians are frequently called upon to assess, diagnose, and stabilize patients who present with acute respiratory failure. This review describes a rapid initial approach to acute respiratory failure in adults, illustrated by two common examples: (1) an airway disease - acute potentially fatal asthma, and (2) a pulmonary parenchymal disease - acute lung injury/acute respiratory distress syndrome. As such patients are usually admitted to hospital, discussion will be focused on those initial management aspects most relevant to the emergency department clinician.

The critically ill asthmatic--from ICU to discharge

Status asthmaticus (SA) is defined as an acute, severe asthma exacerbation that does not respond readily to initial intensive therapy, while near-fatal asthma (NFA) refers loosely to a status asthmaticus attack that progresses to respiratory failure. The in-hospital mortality rate for all asthmatics is between 1% to 5%, but for critically ill asthmatics that require intubation the mortality rate is between 10% to 25% primarily from anoxia and cardiopulmonary arrest. Timely evaluation and treatment in the clinic, emergency room, or ultimately the intensive care unit (ICU) can prevent the morbidity and mortality associated with respiratory failure. Fatal asthma occurs from cardiopulmonary arrest, cerebral anoxia, or a complication of treatments, e.g., barotraumas, and ventilator-associated pneumonia. Mortality is highest in African-Americans, Puerto Rican-Americans, Cuban-Americans, women, and persons aged ≥ 65 years. Critical care physicians or intensivists must be skilled in managing the critically ill asthmatics with respiratory failure and knowledgeable about the few but potentially serious complications associated with mechanical ventilation. Bronchodilator and anti-inflammatory medications remain the standard therapies for managing SA and NFA patients in the ICU. NFA patients on mechanical ventilation require modes that allow for prolonged expiratory time and reverse the dynamic hyperinflation associated with the attack. Several adjuncts to mechanical ventilation, including heliox, general anesthesia, and extra-corporeal carbon dioxide removal, can be used as life-saving measures in extreme cases. Coordination of discharge and follow-up care can safely reduce the length of hospital stay and prevent future attacks of status asthmaticus.

Evaluation of the asthma control test: a reliable determinant of disease stability and a predictor of future exacerbations

BACKGROUND AND OBJECTIVE

This study assessed the asthma control test (ACT) cut-off values for asthma control according to the Global Initiative for Asthma guideline in adults and the effectiveness of ACT scores in predicting exacerbations and serial changes in ACT scores over time in relation to treatment decisions.

METHODS

Subjects completed ACT together with same-day spirometry and fractional concentration of exhaled nitric oxide (FeNO) measurement at baseline and at 3 months. Physicians, blinded to the ACT scores and FeNO values, assessed the patient's asthma control in the past month and adjusted the asthma medications according to management guidelines. Asthma exacerbations and urgent health-care utilization (HCU) at 6 months were recorded.

RESULTS

Three hundred seventy-nine (120 men) asthmatics completed the study. The ACT cut-off for uncontrolled and partly controlled asthma were ≤19 (sensitivity 0.74, specificity 0.67, % correctly classified 69.5) and ≤22, respectively (sensitivity 0.73, specificity 0.71, % correctly classified 72.1). Baseline ACT score had an odds ratio of 2.34 (95% confidence interval: 1.48-3.69) and 2.66 (1.70-4.18) for urgent HCU and exacerbations, respectively, at 6 months (P < 0.0001). However, baseline FeNO and spirometry values had no association with urgent HCU and exacerbations. The 3-month ACT score of ≤20 correlated best with step-up of asthma medications (sensitivity 0.65, specificity 0.81, % correctly classified 72.8). For serial changes of ACT scores over 3 months, the cut-off value was best at ≤3 for treatment decisions with low sensitivity (0.23) and % correctly classified (57.3%) values.

CONCLUSIONS

Single measurement of ACT is useful for assessing asthma control, prediction of exacerbation and changes in treatment decisions.

Asthma diagnosis and management

Asthma is a chronic inflammatory airway disease that is commonly seen in the emergency department (ED). This article provides an evidence-based review of diagnosis and management of asthma. Early recognition of asthma exacerbations and initiation of treatment are essential. Treatment is dictated by the severity of the exacerbation. Treatment involves bronchodilators and corticosteroids. Other treatment modalities including magnesium, heliox, and noninvasive ventilator support are discussed. Safe disposition from the ED can be considered after stabilization of the exacerbation, response to treatment and attaining peak flow measures.

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.

[Live-threatening bronchospasm during anesthesia induction : when pure routine becomes a nightmare]

This article reports a case of live-threatening respiratory failure during induction of anesthesia. An 18-year-old female was admitted to hospital for an axillary abscess incision on a public holiday. The patient had a history of asthmatic episodes and an allergy to milk protein and 2 years previously an asthmatic attack had possibly been treated by mechanical ventilation. Retrospectively, this event turned out to be a cardiac arrest with mechanical ventilation for 24 h. During induction of anesthesia the patient suddenly developed massive bronchospasms and ventilation was impossible for minutes. Oxygen saturation fell below 80% over a period of 12 min with a lowest measurement of 13%. The patient was treated with epinephrine, prednisolone, antihistamine drugs, ß(2)-agonists, s-ketamine and methylxanthines and 15 min later the oxygen saturation returned to normal values. After mild therapeutic hypothermia for 24 h mechanical ventilation was still required for another 4 days. The patient recovered completely and was discharged home on day 19. Initially propofol was suspected of having caused an anaphylactic shock but in retrospect, the diagnosis of near fatal asthma was more likely. The onset of the event was facilitated by the patient playing down the history of asthmatic episodes due to a strong wish for independency and negation of the severity of the disease.

Factors associated with the development of severe asthma exacerbations in children

BACKGROUND

Asthma exacerbations are one of the most common causes of hospitalization in children and account for approximately 10,000 intensive care unit (ICU) admissions per year in the United States. Despite the prevalence of this disease in children, the factors associated with the development of these severe exacerbations are largely unknown.

METHODS

A retrospective case-control study was conducted involving all eligible children admitted to the hospital with asthma for a 1-year period. Potential associated factors and outcomes of children admitted to the ICU with a severe exacerbation (cases) were compared to those of children with acute asthma admitted to the ward (controls).

RESULTS

A total of 188 children were hospitalized with asthma during the study period, 57 (30%) of whom required admission to the ICU. There were no differences in age, gender, or race between cases and controls. Children admitted to the ICU were significantly more likely to have an allergy or irritant-triggered exacerbation than children admitted to the ward (OR 3.9; 95% CI 1.9-8.2; p = .0003). Additionally, children in the ICU had a significantly shorter duration of illness before being admitted to the hospital compared to those admitted to the ward (1.7 ± 2.3 vs. 3.4 ± 4.8 days; p = .002).

CONCLUSIONS

In this retrospective review, severe asthma exacerbations in children are associated with a more rapid onset of symptoms and are more likely to be associated with allergens or irritants, supporting the importance of atopy in this population.

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.

All that wheezes is not asthma--Alternative findings at autopsy

A number of questions must be asked before asthma can be accepted as a valid diagnosis: were the episodes of shortness of breath investigated? Are there changes at autopsy in keeping with asthma? Did asthma either contribute to the terminal episode, cause death, or was it coincidental? Finally, is it possible that other conditions may have accounted for the clinical manifestations? A review of files at FSSA over a 10-year period from 1999 to 2008 identified six cases where shortness of breath and/or wheezing had been incorrectly attributed to asthma. Five were due to pulmonary thromboembolism and one to multiple injuries. In the latter case, an irreducible, left-sided diaphragmatic hernia was present. There was no morphological evidence of asthma in any case. Autopsy examination may, therefore, be crucial in revealing other conditions that may have caused or contributed to episodic breathlessness that may have been incorrectly attributed to asthma.

The systemic and pulmonary immune response to staphylococcal enterotoxins

In response to environmental cues the human pathogen Staphylococcus aureus synthesizes and releases proteinaceous enterotoxins. These enterotoxins are natural etiologic entities of severe food poisoning, toxic shock syndrome, and acute diseases. Staphylococcal enterotoxins are currently listed as Category B Bioterrorism Agents by the Center for Disease Control and Prevention. They are associated with respiratory illnesses, and may contribute to exacerbation of pulmonary disease. This likely stems from the ability of Staphylococcal enterotoxins to elicit powerful episodes of T cell stimulation resulting in release of pro-inflammatory cytokines. Here, we discuss the role of the immune system and potential mechanisms of disease initiation and progression.

[Status asthmaticus. Role of extracorporeal lung assist procedures]

The successful application of a pumpless extracorporeal lung assist procedure ("interventional lung assist, iLA) in three cases of severe refractory status asthmaticus, which could not be solved with conventional pharmacological and respiratory therapy is reported. After an individual risk-benefit analysis such a therapy can be used to reduce lung injury due to invasive mechanical ventilation. Because of the complexity of this therapy it should only be applied in special medical centers with sufficient experience in dealing with extracorporeal lung assist procedures.

Outcome of children with life-threatening asthma necessitating pediatric intensive care

OBJECTIVE

To report the outcome of children with life-threatening asthma (LTA) admitted to a university Pediatric Intensive Care Unit (PICU).

METHODS

Retrospective study between October 2002 and May 2010 was carried out. Every child with LTA and bronchospasm was included.

RESULTS

30 admissions of 28 patients (13 M, 17 F) were identified which accounted for 3% of total PICU admissions (n = 1033) over the study period. The majority of patients were toddlers (median age 3.1 years). Few had past history of prematurity, lung diseases, or neuro-developmental conditions. Approximately half had previous admissions for asthma and one-forth with history of non-compliance to recommended treatment for asthma. One patient had parainfluenza virus and one had rhinovirus isolated. None of these factors were associated with need for mechanical ventilation (n = 6 admissions). Comparing with patients who did not receive mechanical ventilation, ventilated children had significantly higher PIM2 score (1.65 versus 0.4, p < 0.001), higher PCO2 levels (9.3 kPa versus 5.1 kPa, p = 0.01) and longer PICU stay (median 2.5 days versus 2 days, p = 0.03) The majority of patients received systemic corticosteroids, intravenous or inhaled bronchodilators. There was one pneumothorax but no death in this series.

CONCLUSIONS

LTA accounted for a small percentage of PICU admissions. Previous hospital admissions for asthma and history of non-compliance were common. Approximately one quarters required ventilatory supports. Regardless of the need for mechanical ventilation, all patients survived with prompt treatment.

Pitfalls in the evaluation of shortness of breath

This article illustrates the challenges practitioners face evaluating shortness of breath, a common emergency department complaint. Through a series of patient encounters, pitfalls in the evaluation of shortness of breath are reviewed and discussed.