Bronchial Asthma

Bronchial Asthma Diagnosing and Management Presented By: Ahmad Salah Shaheen Under Supervision: Dr.Abdulhakim El.Silwy Assistant Professor of Pediatrics Thamar University College of Medicine

Objectives • To better understand how to differentiate between infants who wheeze and go on to develop asthma and those who wheeze but do not go on to have asthma • To discuss management strategies for treating children with a high risk of developing asthma • To discuss possible prevention therapies for asthma in children four years old or younger

What is Asthma? • Disease of chronic inflammatory disorder of the airways • Characterized by • Airway inflammation • Airflow obstruction • Airway hyperresponsiveness • Reversible process Cookson W. Nature 1999; 402S: B5-11 http://health.allrefer.com/health/asthma-normal-versus-asthmatic-bronchiole.html

Asthmatic Inflammation Normal Airway

Early Asthmatic Response

Late Asthmatic Response

Subacute/Chronic Inflammation

Inhaled trigger chemotactic factors cytokines Bronchoconstriction Mast Cells Alveolar macrophages

Recruitment and activation of inflammatory cells Mucosal Odema  Mucous Secretion

Neural & vascular  effects

What Causes Asthma? • Asthma is a complex trait • Heritable and environmental factors contribute to its pathogenesis. • The inheritance of Asthma is most compatible  with one affected parent ………..25% risk  with two affected parents ……….50% risk • Onset appears early in life and severity remains constant

• Multiple interacting genes • At least 20 distinct chromosomal regions with linkage to asthma and asthma related traits have been identified: Chromosome 5q31 , ADAM33 , PHF11

Neuroendocrine MechanismsStress and Asthma • Common clinical observations of adverse relationship

between stress and human disease • Adverse effects of psychological stress on asthma have been documented. • Depression and stress can augment humoral immunity and favor production of IgE • Growing set of data provide evidence for association between chronic psychological stress and the pathogenesis of atopy and asthma • Marshall G, Ann Allergy Asthma Immunol. 2004;93:S11-S17

Potential Risk Factors1 • Host factors • Genetic predisposition • Atopy • Airway

hyperresponsiveness • Male Gender • Race/Ethnicity • Maternal smoking • Environmental factors • Indoor allergens • Outdoor allergens • Occupational sensitizer

• Environmental factors (cont) • Tobacco smoke • Air pollution • Respiratory infections • Socioeconomic status • Family size • Diet and drugs • Obesity

Masoli M, et al. The Global Burden of Asthma: Executive Summary of the

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Wheezing in Infants • Group 1: Low Lung function: children improve within a few years and "outgrow" their asthma • Group 2: Non-Atopic, viral-induced asthma: also outgrow asthma after a somewhat longer period of time (nonatopic wheezing). • Group 3: Atopic Asthma: in contrast, children who will go on to develop persistent wheezing beyond infancy and early childhood usually have a family history of asthma and allergies and present with allergic symptoms very early in life (atopy-associated asthma).

Differential Diagnosis of Wheezing • Asthma • Congenital Anomalies with airway impingement: Vascular • • • • • • • • • • • •

rings, tracheobronchial obstruction, mediastinal mass H-Type Tracheoesophageal Fistula Bronchopulmonary dysplasia Cystic fibrosis Gastroesophageal reflux Aspiration Foreign Body Aspiration Heart Failure Sinusitis and allergic rhinitis Bronchiolitis Pertussis Tuberculosis Immune system Disorders

Diagnosing Asthma-Not Easy • Clinical diagnosis supported by the certain historical,

physical and laboratory findings • History of episodic symptoms of airflow obstruction (e.g.. breathlessness, wheezing, and COUGH) especially if triggered by inhaled allergen or exercise-response to therapy! • Physical: wheeze, hyperinflation, tachypnea with prolonged expiration • Laboratory: esinophilia of blood and sputum High IgE level Allergy skin test PFT >4 year, exhaled nitric oxide (eNO), spirometry ABGs and pH • Exclude other possibilities

Diagnosing Asthma in Young Children – Asthma Predictive Index • > 4 episodes/yr of

wheezing lasting more than 1 day affecting sleep in a child with one MAJOR or two MINOR criteria

• Major criteria • Parent with asthma • Physician diagnosed atopic dermatitis

• Minor criteria • Physician diagnosed allergic rhinitis • Eosinophilia (>4%) • Wheezing apart from colds

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Adapted from Castro-Rodriquez JA, et al. AJRCCM 2000; 162: 1403

Asthma Diagnosis Made • Identify precipitating factors • Identify comorbid conditions that may aggravate asthma (GERD, allergies etc) • Assess the patient/families knowledge and self management skills • Classify asthma severity using the Guidelines from the NAEPP (Expert Panel)

Assessing Asthma Severity Use Impairment and Risk • Impairment • Symptoms: night time symptoms, reliever

use (SABA), miss school/work, quality of life • Lung function- spirometry (FEV0.5), eNO

• Risk • Recurrent exacerbations including ED visits

and hospitalization (may be normal between events) • At times, hard to differential between impairment and risk

Classifying Asthma Severity in Children • Break down into intermittent, mild, moderate, or

severe persistent asthma depending on symptoms of impairment and risk • Once classified, use the 4 steps depending on the severity to obtain asthma control with the lowest amount of medication • Controller medications (inhaled steroids) should be considered if >4 exacerbations/year, 2 episodes of oral steroids in 6 months, or use of SABA’s (albuterol) more then twice a week • The usual treatment for an acute exacerbation is a high-dose of SABA and a burst of systemic glucocorticosteroids administered orally or intravenously.

Asthma: Goals of Treatment1 • • • • •

Control chronic and nocturnal symptoms Maintain normal activity levels and exercise Maintain near-normal pulmonary function Prevent acute episodes of asthma Minimize emergency department (ED) visits and hospitalizations • Avoid adverse effects of asthma medications Global Initiative for Asthma. GINA workshop report: global strategy for asthma management and prevention. Available at: http://www.ginasthma.org. Accessed October 13, 2006.

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Steps of Therapy • Step 1: intermittent- use SABA • Step 2: mild persistent-use SABA plus one of: ICS OR montelukast OR cromolyn alternatives • Step 3: moderate persistent: SABA + ICS + LABA and/or montelukast • Step 4: severe persistent: SABA + LABA+ ICS and/or montelukast + alternate day predinsolone • Step down: Step down treatment when good control achievement + SABA • Consult asthma specialist if step 3 or higher (consider at step 2)

Maintaining Control • Monitor carefully- every 6 months if stable,

more often if not • If stable after 3 months, try to reduce therapy (usually by 25-50%) • Inhaled steroids are safe even in the young at mild to moderate doses with only a slight decrease in growth velocity. Higher doses have been shown to affect growth, cause cataracts and reduce bone density • Response to therapy is very important in this age group!

Status Asthmaticus Is acute severe and life threating asthma defined as an increasing severe asthma that is not response to drugs that are usually effective Sign of Severity:  Too breathless to feed or speak  RR>50/min  PR>140 bpm  Pulsus paradoxus >15  PEFR <50% predicted Signs of life-threating:  Restless due hypoxia  Drowsiness (hypercabnea)  Exhaustion  Cyanosis  Silent chest  PEFR<33%

Treatment of Status Ashmaticus O2 (high flow) 6L/min Nebulized SABA (salbutamol .05-.15 mg/kg at interval 20-30 min for one hour then should be continued every 1-2 hour)

No Response Check PCo2 and pH 1-Aminophylline 2- IV Hydrocortisone 3- +/-nebulized Ipratropium bromide 4-Nebulized SABA every 1-2 hour should be cont. 5-adequate hydration 6- +/- Antibiotics No improvement Artificial Respiration

Response Oral predinsolone 2mg/kg/day Divided for 3-5 days

Improved

ß2-agonists and O2 As required

Discharge plan

Inhaled Corticosteroid • Preferred treatment alone or in combination • •

• •

for all persistent categories of asthma Safe when use is monitored Reduces asthma symptoms, bronchial hyperreactivity, exacerbations and hospitalizations, need for rescue medications Improves lung function, quality of life May prevent airway remodeling….!!

Role of ICS in Asthma • Trials show that among children with asthma (or at risk for

asthma), controller therapy with ICS is efficacious in controlling asthma symptoms • However, ICS, do not change the natural clinical course of the disease. • PEAK trial 285 children aged 2 to 3 years at high risk for asthma were randomized to therapy with either an ICS (fluticasone, 88 μg twice daily for 2 years) or placebo • Results showed significantly better clinical outcomes and lung function outcomes in children treated with fluticasone than in those treated with placebo • However, clinical differences between groups rapidly disappeared a few weeks after discontinuation of regular treatments. Guilbert et al. Long-term inhaled corticosteroids in preschool children at high risk for asthma, N Engl J Med 354 (2006), pp. 1985–1997

Asthma Prevention • There has been remarkable progress in pharmacotherapy, education and environmental measures in treating asthma • However, no single action has been demonstrated to decrease the risk of developing asthma • Genetic and environmental influences • Prevention will depend on factors influencing the development and progression of asthma

Is Environmental Control Helpful? • Single allergen reduction not

effective • “…Treatment by means of allergen avoidance requires the definition of what patients are allergic to, and additional measures beyond the use of mattress covers and education” Thomas Platts-Mills

http://health.allrefer.com/health/asth ma-common-asthma-triggers.html

Tailored Environmental Intervention • Randomized, controlled trial of environmental intervention • Intervention resulted in

• Reduction in asthma symptoms, disruption in

caretakers plans, caretaker’s and child’s sleep, asthma-related visits to the ER or clinic • Reduction in asthma symptoms were correlated to reduction in allergens

• No difference in reduction of allergens in homes with carpets or without carpets

Morgan WJ, et al. N Engl J Med 2004; 351: 1068-80.

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