Continuous isoproterenol inhalation therapy in children with severe asthmatic attack

Japanese guidelines for childhood asthma 2020

The Japanese Guideline for Childhood Asthma (JGCA) 2020 is a translation of the Japanese Pediatric Guideline for the Treatment and Management of Asthma (JPGL) 2017 into English, which was published by the Japanese Society of Pediatric Allergy and Clinical Immunology. It makes recommendations for best practices in the management of childhood asthma, including management of acute exacerbations and non-pharmacological and pharmacological management. These guidelines will be of interest to non-specialist physicians involved in the care of children with asthma. In JPGL, JPGL2017 is the first evidence-based guidelines updated according to the GRADE system and Minds approach, and it addresses eight clinical questions about the treatment of childhood asthma. In children aged ≤5 years, infant and preschool asthma is diagnosed according to the response to short acting beta2 agonists or the effect of a therapeutic trial during 1 month with controller treatment and worsening after treatment cessation. Long-term management both promotes pharmacological therapy and measures against risk factors that induce exacerbation, better patient education and a partnership with trinity. In addition, long-term management should not be carried out without review but rather be based on a cycle of evaluation, adjustment and treatment. In JPGL2017, the transdermal patch and oral beta2 agonists are positioned as drugs within the concept of "short-term additional treatment" to be used until the symptoms are stabilized when the control state transiently deteriorates.

Low-dose l-isoproterenol versus salbutamol in hospitalized pediatric patients with severe acute exacerbation of asthma: A double-blind, randomized controlled trial

BACKGROUND

Although the guidelines in most countries do not recommend continuous inhalation of l-isoproterenol to treat pediatric patients with acute severe exacerbation of asthma, lower dose of l-isoproterenol has been widely used in Japan. To determine whether the efficacy of low-dose l-isoproterenol was superior to that of salbutamol, we conducted a double-blind, randomized controlled trial.

METHODS

Hospitalized patients aged 1-17 years were eligible if they had severe asthma exacerbation defined by the modified pulmonary index score (MPIS). Patients were randomly assigned (1:1) to receive inhalation of l-isoproterenol (10 μg/kg/h) or salbutamol (500 μg/kg/h) for 12 hours via a large-volume nebulizer with oxygen. The primary outcome was the change in MPIS from baseline to 3 hours after starting inhalation. Trial registration number UMIN000001991.

RESULTS

From December 2009 to October 2013, 83 patients (42 in the l-isoproterenol group and 41 in the salbutamol group) were enrolled into the study. Of these, one patient in the l-isoproterenol group did not receive the study drug and was excluded from the analysis. Compared with salbutamol, l-isoproterenol reduced MPIS more rapidly. Mean (SD) changes in MPIS at 3 hours were -2.9 (2.5) in the l-isoproterenol group and -0.9 (2.3) in the salbutamol group (difference -2.0, 95% confidence interval -3.1 to -0.9; P < 0.001). Adverse events occurred in 1 (2%) and 11 (27%) patients in the l-isoproterenol and salbutamol groups, respectively (P = 0.003). Hypokalemia and tachycardia occurred only in the salbutamol group.

CONCLUSIONS

Low-dose l-isoproterenol has a more rapid effect with fewer adverse events than salbutamol.

Clinical Utility of the Modified Pulmonary Index Score as an Objective Assessment Tool for Acute Asthma Exacerbation in Children

Introduction:

The Modified Pulmonary Index Score (MPIS) was developed as an objective assessment tool for acute asthma exacerbation in children. Although it is considered reliable, there are no known studies of its clinical utility. The objective of this study was to evaluate the validity of the MPIS for children with acute asthma in a clinical setting.

Methods:

In this retrospective study conducted between July 2009 and June 2011 using electronic medical records at the emergency department of a single pediatric medical center in Tokyo, Japan, the MPIS was recorded for patients with acute asthma at initial assessment and after treatment with an inhaled beta-agonist. We evaluated the responsiveness and predictive validity of the MPIS using disposition as an outcome.

Results:

A total of 2242 patients were assessed using the MPIS (median age, 3 years; 71.2% patients were 5 years or younger). The mean (SD) MPIS at initial assessment was 7.1 (3.6) and was significantly higher for the admission group than for the non-admission group (9.9 [2.9] vs. 5.9 [3.1]; P < 0.001). The receiver operator characteristic curve of the initial MPIS for hospital admission demonstrated moderate predictive ability (area under the curve, 0.83). An MPIS reduction of 3 or more indicated a clinically significant change when the MPIS at initial assessment was between 6 and 10 (risk ratio for admission [95% CI], 0.41 [0.28–0.60]; P < 0.001).

Conclusion:

The MPIS demonstrated good concurrent validity, predictive validity, and responsiveness in a wide range of clinical settings.

Japanese guidelines for childhood asthma 2017

The Japanese Guideline for the Diagnosis and Treatment of Allergic Diseases 2017 (JAGL 2017) includes a minor revision of the Japanese Pediatric Guideline for the Treatment and Management of Asthma 2012 (JPGL 2012) by the Japanese Society of Pediatric Allergy and Clinical Immunology. The section on child asthma in JAGL 2017 provides information on how to diagnose asthma between infancy and adolescence (0-15 years of age). It makes recommendations for best practices in the management of childhood asthma, including management of acute exacerbations and non-pharmacological and pharmacological management. This guideline will be of interest to non-specialist physicians involved in the care of children with asthma. JAGL differs from the Global Initiative for Asthma Guideline in that JAGL emphasizes diagnosis and early intervention of children with asthma at <2 years or 2-5 years of age. The first choice of treatment depends on the severity and frequency of symptoms. Pharmacological management, including step-up or step-down of drugs used for long-term management based on the status of asthma control levels, is easy to understand; thus, this guideline is suitable for the routine medical care of children with asthma. JAGL also recommends using a control test in children, so that the physician aims for complete control by avoiding exacerbating factors and appropriately using anti-inflammatory drugs (for example, inhaled corticosteroids and leukotriene receptor antagonists).

Japanese Guideline for Childhood Asthma 2014

The Japanese Guideline for the Diagnosis and Treatment of Allergic Diseases 2013 (JAGL 2013) describes childhood asthma after the Japanese Pediatric Guideline for the Treatment and Management of Asthma 2012 (JPGL 2012) by the Japanese Society of Pediatric Allergy and Clinical Immunology. JAGL 2013 provides information on diagnosis by age group from infancy to puberty (0-15 years of age), treatment for acute exacerbations, long-term management by anti-inflammatory drugs, daily life guidance, and patient education to allow non-specialist physicians to refer to this guideline for routine medical treatment. JAGL differs from the Global Initiative for Asthma Guideline (GINA) in that JAGL emphasizes early diagnosis and intervention at <2 years and 2-5 years of age. A management method, including step-up or step-down of long-term management drugs based on the status of asthma control levels, as in JAGL, is easy to understand, and thus the Guideline is suitable as a frame of reference for routine medical treatment. JAGL has also introduced treatment and management using a control test on children, recommending that the physician aim at complete control by avoiding exacerbation factors and by appropriate use of anti-inflammatory drugs.

Pediatric allergy and immunology in Japan

The Japanese Society of Pediatric Allergy and Clinical Immunology (JSPACI) was started in 1966 and currently has 3613 members as of August 1, 2012. The number of pediatricians specializing in allergies who have been certified by the Japanese Society of Allergology is 817. Among these, there are 125 training directors and training facilities for allergy and clinical immunology. The JSPACI first published an asthma guideline specific for children in 2000, and this has been revised every 3 yrs, contributing to better control of pediatric asthma. Food allergy management guidelines were first developed in 2005, which have helped to improve the care of food allergy patients. Among 514 pediatric training programs by the Japanese Society of Pediatrics, there are 312 facilities routinely performing oral food challenges. Among these, there were already 53 facilities performing oral immunotherapy at the end of 2011, treating 1400 cases of food allergy. The prevalence of pediatric allergic diseases has increased in Japan over the past 50 yrs. A number of International Study of Asthma and Allergies in Childhood surveys have been conducted in the past at specific times. The prevalence of wheezing among children aged 13-14 yrs in 2002 was 13.0%. Multi-year surveys found a 1.5- to 2-fold increase every 10 yrs until 2002. However, according to the latest data in 2012, asthma prevalence seems to have slightly decreased in Japan. Food allergy mainly associated with infantile atopic eczema among infants younger than 1 yr of age is the most common form as with other developed countries. The estimated food allergy prevalence based on data from several surveys is 5-10% among infants (0-6 yrs) and 1-2% among schoolchildren (6-15 yrs). A variety of patients suffering from primary deficiency syndrome have been actively analyzed. Previously, antibody defects and well-defined syndromes with immunodeficiency were analyzed, but recent research is focusing on not only acquired immune disorders but also on innate immune disorders. In contrast to the widespread use of oral immunotherapy, one immediate issue is to develop and reassess subcutaneous and sublingual immunotherapies for mite and Japanese cedar pollen antigens that have been disused in Japan since the 1990s.

Japanese guideline for childhood asthma

The Japanese Guideline for the Diagnosis and Treatment of Allergic Diseases 2010 (JAGL 2010) describes childhood asthma based on the Japanese Pediatric Guideline for the Treatment and Management of Asthma 2008 (JPGL 2008) published by the Japanese Society of Pediatric Allergy and Clinical Immunology. JAGL 2010 provides information on diagnosis by age groups from infancy to puberty, treatment for acute exacerbations, long-term management by medication, daily life guidance, and patient education to allow physicians, not specialized in childhood asthma, to refer to this guideline for routine medical treatment. JAGL differs from the Global Initiative for Asthma Guideline (GINA) in that the former emphasizes long-term management of childhood asthma based on asthma severity and early diagnosis and intervention at <2 years and 2-5 years of age. However, a management method, including step-up or step-down of long-term management agents based on the status of asthma symptoms, is easy to understand and thus JAGL is suitable for routine medical treatment. JAGL also introduced treatment and management using a control test for children, recommending treatment and management aimed at complete control through avoiding exacerbation factors and appropriate use of antiinflammatory agents.

Japanese pediatric guidelines for the treatment and management of bronchial asthma 2008

Abstract The fourth version of the Japanese Pediatric Guidelines for the Treatment and Management of Bronchial Asthma 2008 (JPGL 2008) was published by the Japanese Society of Pediatric Allergy and Clinical Immunology in December 2008. In JPGL 2008, the recommendations were revised on the basis of the JPGL 2005. The JPGL 2008 is different to the Global Initiative for Asthma guideline in that it contains the following items: a classification system of asthma severity; recommendations for long-term management organized by age; a special mention of infantile asthma; and an emphasis on prevention and early intervention. Here we show a summary of the JPGL 2008 revising our previous report concerning JPGL 2005.

New Japanese pediatric guidelines for the treatment and management of bronchial asthma

There have been a number of guidelines for asthma treatment published throughout the world. However, childhood asthma guidelines must be developed in consideration of the background of the individual countries. The second version of the Japanese Pediatric Guideline for the Treatment and Management of Bronchial Asthma 2002 (JPGL 2002) was published by the Japanese Society of Pediatric Allergy and Clinical Immunology (JSPACI) in November 2002, and was popular among Japanese physicians. After the publication of the JPGL, the incidence of pediatric asthma deaths decreased in Japan. In JPGL 2005 the recommendations were re-edited based on Global Initiative for Asthma (GINA) and the JPGL 2002. In comparison to the GINA guidelines, the JPGL 2005 include a classification system of asthma severity, recommendations for long-term management organized by age, a special mention of infantile asthma, and an emphasis on prevention and early intervention.

The role of intrinsic efficacy in determining response to a beta2-agonist in acute severe asthma

BACKGROUND

Current guidelines recommend repeated doses of albuterol for the emergency treatment of acute asthma. However, approximately one-third of patients show little or no initial response to this partial beta(2)-agonist.

METHODS

We conducted a randomized, double-blind, proof-of-concept study to investigate whether a full beta(2)-agonist, isoproterenol, offers a therapeutic advantage in adults presenting with acute severe asthma (FEV(1)<50%) who fail to respond to an initial treatment of the partial beta(2)-agonist, albuterol. Study subjects were randomized to receive a 2-h continuous nebulization of either albuterol (7.5mg/h) (n=10, mean FEV(1)=37% predicted) or isoproterenol (7.5mg/h) (n=9, mean FEV(1)=33% predicted). Respiratory symptoms, vital signs and pulmonary function measures were collected.

RESULTS

Subjects from both treatment groups had similar baseline characteristics. The percent improvements from baseline FEV(1) at 60 and 120min were significantly higher in subjects receiving isoproterenol than those receiving albuterol (44 vs. 17% and 63 vs. 24%, respectively, P<0.05). The change in symptoms measured by the modified Borg score was also significantly greater in subjects receiving isoproterenol (P<0.01). Both treatments were well tolerated, though the mean increase in pulse rate at 60 and 120min (21 vs. 1 and 23 vs. 6beats/min, respectively, P<0.05) and the mean change in serum potassium at 120min (-0.52 vs. -0.07meq/L, P<0.05) from baseline were significantly greater in the isoproterenol group.

CONCLUSIONS

Our data suggest that in subjects presenting with acute severe asthma who fail to show an initial response to albuterol, the use of a beta(2)-agonist of higher intrinsic efficacy can be more effective in improving lung function and symptoms.

Differential effects of short-acting beta2-agonists on human granulocyte functions

BACKGROUND

beta2-Adrenergic agonists play a pivotal role in the management of bronchial asthma. Although the major effect of short-acting beta2-agonists on the airway is relaxation of smooth muscles, they may also have several effects on surrounding immunomodulatory cells.

METHODS

We examined whether widely used short-acting beta2-agonists differ in their ability to modulate granulocyte functions, such as superoxide anion (O2-) production and degranulation.

RESULTS

Procaterol (PC), a full agonist, significantly inhibited both O2- production by granulocytes (neutrophils and eosinophils) and their degranulation at the clinically relevant concentrations, whereas salbutamol and tulobuterol (partial agonists) showed smaller effects. PC inhibited N-formyl methionyl-leucyl-phenylalanine-induced O2- production and peroxidase release, but failed to inhibit responses induced by phorbol 12-myristate 13-acetate and/or opsonized zymosan. Exposure to 5 x 10(-8)M PC for 120 min resulted in approximately 50% inhibition of O2- production and degranulation of neutrophils. The effects of beta2-agonists were more obvious in neutrophils than in eosinophils. A selective beta2-receptor antagonist, ICI-118551, reversed the inhibitory effect of beta2-agonists (PC, salbutamol, tulobuterol B) on N-formyl methionyl-leucyl-phenylalanine-induced O2- production.

CONCLUSIONS

These results suggest that beta2-agonists had an inhibitory effect on granulocyte functions, mainly mediated viareceptors and their efficacy. Our observations support that beta2-agonists with a rapid onset of action and high intrinsic efficacy (short-acting and full agonists) may be optimal for the rescue therapy against acute asthma attack and sedation of its airway inflammation in an early phase.