From Chronic Lung Disease of Infancy to Asthma

Transcription

1 From Chronic Lung Disease of Infancy to Asthma Mollie V. Anderson, CPNP Certified Pediatric Nurse Practitioner Pediatric Lung Care Bon Secours Medical Group St. Mary s Hospital 1 Mollie V. Anderson, CPNP I have no conflicts of interest to disclose. 2 1

2 Objectives 1. The learner will be able to describe the physiology of chronic lung disease of infancy. 2. The learner will be able to differentiate between the symptoms of chronic lung disease of infancy, asthma, and other lung diseases. 3. The learner will be able to describe the care of babies with chronic lung disease of infancy and children with asthma. 3 Definition of CLD of infancy (BPD) Need for supplemental oxygen or positive pressure ventilation for >28 days. New vs Classic (CLD/BPD) clinical features change based on new technologies and approaches to care such as surfactant, permissive hypercapnia, and noninvasive ventilation. This has lead to increased survival of extremely LBW infants. 4 2

3 Classic BPD Before surfactant therapy and recent noninvasive ventilation the most prominent features of BPD were airway injury with inflammation and alveolar septic fibrosis. These was associated with oxygen toxicity, barotrauma, and infection. Some have chronic changes, clinically and radiographically, into adulthood. 5 New BPD Primarily characterized by impaired alveolar development due to extreme premature birth and ELBW. Infant survival increased after the advent of antepartum glucocorticosteroids and surfactant. The lungs are characterized by fewer alveoli, larger alveoli, and dysmorphic pulmonary vasculature. 6 3

4 Additional Risk Factors for Lung Injury Swallowing dysfunction Gastroesophageal reflux Poor growth Infection 7 Care of the NICU Grad Growth optimizing nutrition Medication, oxygen Avoiding illness Immunizations Synagis Flu vaccine for patients and families Cigarette smoke avoidance Multidisciplinary approach 8 4

5 Respiratory Disorders Associated with BPD Asthma like symptoms Preschoolers wheeze Adolescent reduced exercise tolerance Less likely to respond to bronchodilators less airway hyperresponsiveness Lung pathophysiology older BPD patient (teenager and adult) airway wall thickening like patients with asthma but they have morphologic changes seen on CT scan. 9 Pulmonary Function Testing with BPD Tested at 5 years of age. Measures objective lung function. Used to assess children with chronic cough, exercise intolerance, or other chronic respiratory symptoms. With mild disease the PFTs improve over time with new alveolar development and may respond to bronchodilators. Clinical symptoms of BPD improve but PFTs remain abnormal in severe disease. 10 5

6 Summary In EPICure study of infants born <26 weeks gestation, 25% had a diagnosis of asthma at 11 years of age and 56% had abnormal spirometry. Children with BPD are less likely to have airway hyperreponsiveness that characterizes asthma and less likely to respond to bronchodilators. Only 40 50% of children with BPD respond to bronchodilators. 11 Childhood asthma One of the most common chronic diseases of childhood. In US asthma affects >7 million children Asthma accounts for >2 million ED visits Health care costs of asthma are >6 billion There are an estimated 3 million lost work days per year It is the leading cause of school absenteeism. 12 6

7 Classifying Asthma 4 Severe Persistent 3 Moderate Persistent 2 Mild Persistent? Note: Severe Intermittent Classification is made off therapy 1 Mild Intermittent 13 Patients in the US Overestimate Their Asthma Control Of patients who report symptoms that meet NIH criteria for moderate-persistent asthma 61% still consider their asthma to be well controlled or completely controlled Of patients who report symptoms that meet NIH criteria for severe-persistent asthma 32% still consider their asthma to be well controlled or completely controlled Asthma in America Survey. SRBI. December

8 What is Asthma? Airway obstruction Usually reversible Recurrent Characterized by airway inflammation and increased airway responsiveness 15 These Terms Are Often Used for Asthma or Related Illness Chronic bronchitis Reactive airways disease Wheezing bronchitis WARI - Wheezing associated with respiratory disease Recurrent bronchiolitis 16 8

9 How Does Asthma Present in the Pediatric Age Group? Wheezing Coughing Recurrent or persistent pulmonary atelectasis (pneumonia) Recurrent croup Exercise-induced asthma 17 Diagnostic Tests History* Physical examination Response to therapy* Pulmonary Function and Challenge testing* FeNO is getting more utilization for determining the degree of airway inflammation Skin test -measures allergy specific IgE present on tissue mast cells. RAST - measures serum allergen specific IgE less sensitive and less specific than skin tests 18 9

10 What Is Bronchial Hyperresponsiveness? Airways that respond by broncho-constriction to agents at much lower concentration/dose than in normal individuals It can be demonstrated in the laboratory by bronchochallenge testing 19 Asthma Pathophysiology Bronchospasm Smooth muscle dysfunction Airway inflammation Airway remodeling 20 10

11 Inflammation and Bronchospasm I show this graphic to my patients 21 Epithelial Remodeling in Asthma Normal Asthmatic Jeffery P. Asthma

12 OUR APPROACH ê Education ê Practical avoidance ê A controller medication 23 Education What to educate about Pathophysiology Environmental controls Medications Delivery of medications Who to educate Demonstration 24 12

13 Practical Avoidance Cigarette smoke exposure avoidance! If one wheezes when they pet the cat don t pet the cat! If your child coughs and wheezes when they mow the grass, have them take out the garbage. If the patient has exercise-induced bronchospasm don t avoid exercise take preventative medication and warm up slowly. If one is atopic have them do appropriate house dust mite, mold, and cockroach control regardless of skin tests. If they are not atopic, then environmental controls may be helpful in prevention - regardless they will have a cleaner house. 25 Controller Medications Oral Inhaled Corticosteroids Leukotriene modifiers (montelukast)* Mast cell stabilizers (cromolyn, nedocromil)* Long-active 2 agonist (salmeterol)* *Note that all controller medications are not necessarily anti-inflammatory and therefore may not prevent airway remodeling

14 Oral Inhaled Corticosteroids Most effective controller medication Used properly ICS are safe and have far less potential risks than intermittent low dose systemic corticosteroids Use the lowest effective dose 27 Fear of OIS Side Effects Untreated asthma may decrease growth OIC may cause slowing of growth velocity during the 1st year of use. However, growth potential and final height are likely to be normal or near normal. Catch-up occurs while on OIS. Dysphonia occurs uncommonly Oral candidiasis may occur especially with improper inhaler technique

15 Undertreating Asthma Undertreating asthma is a far greater risk than treatment with oral inhaled corticosteroids. Consider the following: Life threatening illness Sick visits, ER visits, Hospitalization Always sick Not able to participate in normal childhood activities School absentism, Parental missed work 29 Rescue Medications 2 agonists i.e. albuterol/xopenex Iprotropium bromide Atrovent Short course of prednisone Some are using increased doses of OIS as rescue (unpublished data) 30 15

16 Other Medications Xolair therapeutic monclonal antibody directed against IgE Nucala therapeutic monoclonal antibody which is an interleukin-5 receptor antagonist. 31 Medication Delivery Nebulizer Metered Dose Inhaler (MDI) Dry powder inhaler (DPI) Conventional appearance (as MDI) Diskus Turbuhaler 32 16

17 Nebulization Therapy Nebulize when awake. Good quiet babies only deliver ~43%. Crying baby -Lung dose decreased 75%! Hold mask only 1 cm from face - lose 60%! Hold mask only 2 cm from face - lose 85%! Blow by - forget it!!!!!!!!! Nose filters ~50% of dose! Small volume - reduces dose significantly 33 Age Appropriate Aerosol Delivery Nebulizer Infants, toddlers, and totally discombobulated children and adults MDI/spacer with mask Under 4-6 years of age MDI/spacer with mouthpiece 4-6 years and older Dry powder inhaler Over 5 years of age 34 17

18 What Are the Goals of Asthma Therapy? To treat the airway inflammation until normal To maintain the airways in a normal physiological state with minimal drug therapy To avoid, if possible, complications of drug therapy 35 Miscellaneous Pearls and Treatment Considerations in Asthma In the child with chronic asthma, a chronic controller medication is needed to prevent airway inflammation and decrease bronchial hyperresponsiveness - and hopefully prevent airway remodeling. Remind patients not to discontinue the controller medicine when well! 36 18

19 Miscellaneous pearls and treatment considerations in asthma Routine controller medications, as a rule, do not need to be discontinued when using short courses of oral prednisone it confuses the patient and they frequently forget to go back on them after the prednisone course is completed. Explain the medications - demonstrate the technique - have patient demonstrate technique every visit. Give the patient written instructions. 37 Miscellaneous pearls and treatment considerations in asthma Medication delivery systems can be used in many different combinations but remember inappropriate inhaler/nebulizer technique is often the reason for failure of asthma control. Don t assume a nebulizer is an easy thing to use! Not held on face properly Crying Nose breathing Wrong size mask Disposable product - intended for limited reusing I have even seen them used with a pacifier in mouth! 38 19

20 Miscellaneous pearls and treatment considerations in asthma Use a spacer for all metered dose inhalers! They significantly improve medication delivery and decrease side effects - MDI delivered medications are not beneficial if the only reach the back of the throat. We strongly recommended when using multiple inhalers that those that are chosen utilize the SAME technique. 39 Miscellaneous pearls and treatment considerations in asthma See the patient frequently for follow-up, especially those with moderate to severe chronic illness. This is the key to compliance in chronic disease. Start with "a lot" of medication, get the symptoms under control, and then decrease (step down) the medications

21 Education is (the) KEY to successful therapy! 41 21