Selected abstracts:

1.                  Beers SL, Abramo TJ, Bracken A, Wiebe RA.  Bilevel positive airway pressure in the treatment of status asthmaticus in pediatrics. Am J Emerg Med. 2007 Jan;25(1):6-9. 

University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390, USA. sara.beers@childrens.com

OBJECTIVES: The aim of this study was to examine the safety, patient tolerance, and possible benefit of bilevel positive airway pressure (BiPAP) in conjunction with beta-2 agonist therapy in the treatment of pediatric patients with status asthmaticus who were refractory to conventional medical therapy. METHODS: This descriptive retrospective chart review examined all patients with the diagnosis of acute asthma treated with BiPAP in an urban academic pediatric emergency department (ED) from April 1, 2003, to August 31, 2004. RESULTS: Eighty-three patients with status asthmaticus refractory to conventional pharmacological treatment were placed on BiPAP with beta-2 agonist nebulization in the ED. The number of subjects tolerating BiPAP was 73 (88%) of 83 patients. All patients placed on BiPAP in the ED were initially designated for admission to the pediatric intensive care unit (PICU). However, only 78% (57/73) were actually admitted to the PICU. Sixteen patients on BiPAP were admitted to a ward service; of these patients, none were subsequently transferred to the PICU. In addition, there was an immediate improvement in subjects' clinical status upon initiation of BiPAP, with 77% showing a decrease in respiratory rate, averaging 23.6% (range, 4%-50%), and 88% showing an improved oxygen saturation, averaging 6.6 percentage points (1-28 percentage points). There were no adverse events due to the use of BiPAP. CONCLUSIONS: These results suggest that the addition of BiPAP in treating pediatric status asthmaticus is safe and well tolerated. This intervention shows promise as a beneficial adjunct to conventional medical treatments. However, further prospective investigation is warranted to confirm these findings.

2.                  Beasley R, Aldington S.  Magnesium in the treatment of asthma. Curr Opin Allergy Clin Immunol. 2007 Feb;7(1):107-10.

Medical Research Institute of New Zealand, Wellington, New Zealand. Richard.Beasley@mrinz.ac.nz

PURPOSE OF REVIEW: To provide an update of recent research on the role of magnesium in the management of asthma. RECENT FINDINGS: Further evidence has been published that long-term oral magnesium supplementation does not lead to improved control in adult asthma. In contrast, updated meta-analyses of randomized controlled trials have confirmed the efficacy of both intravenous and inhaled (as an adjuvant to salbutamol nebulizer solution) magnesium therapy in severe asthma. This conclusion is still limited by the paucity of randomized controlled trials, however, with many issues yet to be firmly established, such as the efficacy in different patient subgroups, the dose regimes, and the optimal method of administration.International guidelines currently recommend the use of intravenous magnesium in severe asthma, and there is evidence that this approach is now widely used in emergency departments in North America. This audit also illustrated the emerging unregistered use of nebulized magnesium/salbutamol solution. SUMMARY: Further investigation of the efficacy and safety of magnesium in severe asthma is now urgently required to determine its role in this clinical situation. The research community must heed the call for more research that is being made by funding agencies dealing with this area.

3.                  Dhand R, Mercier E.  Effective inhaled drug administration to mechanically ventilated patients. Expert Opin Drug Deliv. 2007 Jan;4(1):47-61. 

University of Missouri-Columbia, Division of Pulmonary, Critical Care and Environmental Medicine, MA-421 Health Sciences Center; DC043.00; 1 Hospital Drive, Columbia, MO 65212, USA. dhandr@health.missouri.edu

Inhaled therapy is commonly employed in mechanically ventilated patients with chronic obstructive pulmonary disease or asthma. The efficacy of inhaled drugs is comparable to that achieved with systemic routes of administration, but the dose of drug required to achieve a therapeutic effect is generally much smaller. Moreover, limited systemic absorption of inhaled drugs minimises systemic side effects. Aerosol administration to ventilated patients differs from that in ambulatory patients in several respects. Optimal techniques for using pressurised metered-dose inhalers and nebulisers in ventilator circuits have been developed. With these techniques, the efficiency of inhaled drug delivery in mechanically ventilated patients is now comparable to that in ambulatory patients. Pressurised metered-dose inhalers are chiefly used to deliver bronchodilator and corticosteroid aerosols, and are more efficient and convenient to use than nebulisers for routine therapy in ventilated patients. However, nebulisers are more versatile and are employed to generate aerosols of bronchodilators, corticosteroids, antibiotics, prostaglandins, surfactant and mucolytic agents. Improvements in drug formulations and the design and efficiency of aerosol generating devices have led to increasing application of inhaled therapies in mechanically ventilated patients.

4.                  Jindal SK. Bronchial asthma: the Indian scene. Curr Opin Pulm Med. 2007 Jan;13(1):8-12.

Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh, India. skjindal@indiachest.org

PURPOSE OF REVIEW: Although asthma is a global disease, there are important differences in epidemiology, clinical spectrum and management practices in India. Some of these issues have been reviewed in this article. RECENT FINDINGS: The prevalence of 'ever asthma' was reported in 2.4% in a population study on 73,605 individuals conducted simultaneously at four major centres in India with the use of a single definition and uniform methodology employing a validated questionnaire. Of the several risk factors which were found to be significant, exposure to environmental tobacco smoke during childhood alone or both during childhood and adulthood was important in the development of and in increasing morbidity from asthma. Many other triggers and risk factors which include local aeroallergens and air pollutants have been identified. Allergic bronchopulmonary aspergillosis is an important cause of difficult to treat asthma and almost half of these patients receive antitubercular treatment at some stage. Simplified consensus guidelines based on international guidelines and local practices have been developed for use at the primary and secondary levels of healthcare. SUMMARY: The prevalence of asthma in India is somewhat similar to that seen in other Asian countries. Consensus management guidelines adapted from standard international guidelines adequately address the local concerns and issues.

5.                  Kaza V, Bandi V, Guntupalli KK.  Acute severe asthma: recent advances. Curr Opin Pulm Med. 2007 Jan;13(1):1-7.

Pulmonary and Critical Care Medicine, Baylor College of Medicine, Houston, Texas 77030, USA.

PURPOSE OF REVIEW: Acute severe asthma is challenging to the clinician both in terms of recognition and appropriate treatment. About 30% of these episodes need admission to the medical intensive care unit with a mortality of 8%. Relapse rates vary from 7 to 15% depending on how well the patient is managed. The purpose of this review is to discuss recent advances in identification of risk factors, pathophysiology and management of acute severe asthma. RECENT FINDINGS: Although the exact mechanism for acute severe asthma is unclear, some that are implicated include inflammation, airway remodeling and downregulation of beta-receptors. None of the environmental factors have been clearly related to the development of near fatal attacks. Genetic polymorphisms have been associated with severe asthma. Lack of steroid responsiveness has been linked to severe asthma attacks. Chemokines and basement membrane changes characteristic of severe asthma are reported in a few studies. Lack of symptom perception in a certain group of patients with acute severe asthma leads to delayed interventions. Specific treatment modalities and ventilator management is reviewed. SUMMARY: Severe asthma is a phenotype of asthma with variable pathology and clinical presentation. Early recognition and timely intervention is needed to prevent significant mortality and morbidity.

6.                  Nisar N, Guleria R, Kumar S, Chand Chawla T, Ranjan Biswas N. Mycoplasma pneumoniae and its role in asthma. Postgrad Med J. 2007 Feb;83(976):100-4.

Department of Pharmacology, All India Institute of Medical Sciences, New Delhi, India.

Mycoplasma pneumoniae (M pneumoniae), primarily recognised as a causative agent of community-acquired pneumonia has recently been linked to asthma. An infection with M pneumoniae may precede the onset of asthma or exacerbate asthma symptoms. Chronic infection with M pneumoniae has been suspected to play a part in some patients with asthma. The role of immunoglobulin E-related hypersensitivity and induction of T helper type 2 immune response leading to inflammatory response in M pneumoniae-infected patients with asthma have also been proposed. Use of macrolides in reducing asthma symptoms only in M pneumoniae-infected patients supports the use of macrolides in patients with asthma having M pneumoniae infection. As macrolides are both antimicrobial and anti-inflammatory drugs, the therapeutic role of their biphasic nature in reducing asthma symptoms needs further attention in clinical research.

7.                  Patton JS, Byron PR.  Inhaling medicines: delivering drugs to the body through the lungs. Nat Rev Drug Discov. 2007 Jan;6(1):67-74.

Nektar Therapeutics, 150 Industrial Road, San Carlos, California 94070, USA. jpatton@nektar.com

Remarkably, with the exception of anaesthetic gases, the ancient human practice of inhaling substances into the lungs for systemic effect has only just begun to be adopted by modern medicine. Treatment of asthma by inhaled drugs began in earnest in the 1950s, and now such 'topical' or targeted treatment with inhaled drugs is considered for treating many other lung diseases. More recently, major advances have led to increasing interest in systemic delivery of drugs by inhalation. Small molecules can be delivered with very rapid action, low metabolism and high bioavailability; and macromolecules can be delivered without injections, as highlighted by the recent approval of the first inhaled insulin product. Here, we review these advances, and discuss aspects of lung physiology and formulation composition that influence the systemic delivery of inhaled therapeutics.

8.                  Polosa R.  Critical appraisal of antileukotriene use in asthma management. Curr Opin Pulm Med. 2007 Jan;13(1):24-30.

Department of Internal and Specialist Medicine, Ascoli-Tomaselli Hospitals, University of Catania, Italy. polosa@unict.it

PURPOSE OF REVIEW: Recognition of the importance of leukotrienes in the pathogenesis of asthma has led to the development of leukotriene modifiers, the first new class of drugs for asthma treatment to become available since the introduction of inhaled corticosteroids. Nevertheless, despite their widespread use in clinical practice, the role of leukotriene modifiers in the management of asthma remains controversial. In the present article the clinical applications of this class of drugs have been critically reviewed based on recent evidence. RECENT FINDINGS: In an effort to try and establish the proper place of antileukotrienes in the management of asthma, important systematic reviews have been carried out over these recent years in three critical areas: antileukotrienes as second choice first line agents after inhaled corticosteroids; antileukotrienes as add-on therapy to inhaled corticosteroids; add-on antileukotrienes versus long acting beta-agonists to patients not controlled by inhaled corticosteroids. In addition, novel and useful clinical targets for this class of drugs have been recently explored and include: patients with severe asthma; aspirin-intolerant asthma; asthmatic patients with allergic rhinitis. SUMMARY: Use of antileukotrienes is not recommended as first-line monotherapy in patients with asthma, except those who have aspirin intolerant asthma. Patients with concomitant allergic rhinitis may be a good target population for therapy with antileukotrienes. Addition of leukotriene modifiers to inhaled corticosteroids produces only a modest improvement in the clinical response, and is not greater to that of add-on long acting beta-agonists. The exact role of antileukotrienes in asthma management guidelines still continues to evolve.

9.                  Sylvester KP, Patey RA, Broughton S, Rafferty GF, Rees D, Thein SL, Greenough A.   Temporal relationship of asthma to acute chest syndrome in sickle cell disease. Pediatr Pulmonol. 2007 Feb;42(2):103-6.

Division of Asthma, Allergy and Lung Biology, King's College London, United Kingdom.

Acute chest syndrome (ACS) is an important cause of mortality and morbidity in children with sickle cell disease (SCD). An association between asthma and ACS has been reported. Our aims were to determine whether asthma was more common in SCD children than controls and the relationship of the timing of the SCD children's first ACS episode to a diagnosis of asthma. One hundred and sixty-five SCD children median age 8.2 (range 0.3-17.3) years and 151 similar ethnic origin and aged controls were prospectively recruited into the study and a detailed history was taken from all of the children to determine if they were taking anti-asthma medication. The medical records of the SCD children were examined to assess whether they had an ACS episode, the age this episode occurred and when any diagnosis of asthma had been made. A similar proportion of the SCD children and controls were taking anti-asthma medication (7% and 9%). Thirty-three SCD children had at least one ACS episode. More of the children who had an ACS compared to those who had not were taking anti-asthma medication (P = 0.02). The ACS children had been diagnosed as asthmatic at a median of 3.5 (range 0.5-7) years prior to their first ACS episode. In conclusion, these results suggest asthma exacerbations may predispose to ACS episodes. (c) 2006 Wiley-Liss, Inc.