Chapter 13 Patho Flashcards
- what is the NAEPP?
national asthma education and prevention program
- first evidence based asthma guidelines were published in
1991
- Today the NAEPP guideline are structured around the following four components
- assessment and monitoring of asthma
- PT education
- control of factors contributing to asthma severity
- the pharmacologic treatments
- GINA
global initiative for asthma launched in 1993
- Some of GINA’s goals
awareness of asthma, research, reduce asthma morbidity and mortality, improve management of asthma, improve availability and accessibility of effective asthma therapy.
- Anatomic alterations of the lungs w/ asthma
- smooth muscle constriction of bronchial airways
- excessive production of thick white bronchial secretions
- mucous plugging
- hyperinflation of alveoli
- atelectasis caused by mucous plug
- bronchial wall inflammation leading to fibrosis
- also w/ asthma
inside of airway swells and mast cells release histamine
- asthma was first recognized
by Hippocrates more than 2000 years ago
- according to CDC/NCHS
prevalence of asthma in the US has increase from 7.3% to 8.4%, 1 in 11 children have asthma and 1 in 12 adults have asthma, its estimated that 25.7 million people suffer from asthma
- number of americans hospitalized annually for severe asthma
500,000
- number of people in US who die annually due to asthma
3200
- The WHO estimates that about
235 million people suffer from asthma world wide
- asthma is about two times more prevalent in boys than girls during
childhood
- approx. 50% of people w/ asthma develop it before
age 10
- two types of asthma
extrinsic and intrinsic , significant overlap exists
- extrinsic asthma
allergic or atopic asthma, asthma episode clearly linked to the exposure of a specific allergen (antigen)
- ex of extrinsic asthma allergens
dust, mites, fur, cockroach, fungi, molds, yeast, pollen
- extrinsic asthma is
an immediate type 1 anaphylactic hypersensitivity reaction, it is family related and usually appears before 30, it often disappears after puberty
- Because extrinsic asthma is associated w/ an antigen -antibody induced bronchospasm
an immunologic mechanism plans an important role. (IgE) immunoglobulin-E
- PT w/ extrinsic asthma may demonstrate
- early asthmatic response , within minutes after exposure and resolves with in an hour.
- late asthmatic response , begins several hours after exposure and last much longer.
- biphasic response, begin early but does not resolve
- Intrinsic asthma
nonallergic or nonatopic asthma, episode cannot be directly linked to a specific antigen or extrinsic factor. these PT have normal serum IgE levels. onset usually occurs after the age of 40.
- Risk factors
- host: genetics, obesity, sex
2. enviromental: allergens, infections, occupational sensitizers, tobacco smoke, diet
- other risk factors
drugs, food additive and preservatives , exercise, gerd, sleep, emotional stress, perimenstrual, allergic bronchopulmonary aspergillosis
- Indicators for asthma
wheezing, recurrent cough, difficult breathing, chest tightness
- asthma symptoms occur or worsen
at night, awakening the PT, in a seasonal pattern, if PT has eczema, hay fever, or family history of asthma or atopic diseases. also if PT has a cold that goes to the chest for takes longer than 10 days to clear up.
- asthma symptoms worsen in the presence of
fur, aerosol chemicals, change in temp, dust mites, drugs, aspirin or beta blockers, exercise, pollen, resp infections, smoke, strong emotions
- Tests for asthma
FEV1, FEV1/FVC , PEFR
- ***An increase in FEV1 greater than or equal to
12% AND greater than or equal to 200 ml after administration of a bronchodilator suggests reversible airflow limitation consistent w/ asthma.
- Normal FEV1/FVC
greater than .75-.80. anything less than this indicates airflow limitation and asthma should be suspected. ( most hospital use .70 as normal)
- An improvement of 60 L/min
or greater than or equal to 20% of the prebronchodilator PEFR after inhalation of a bronchodilator,
- Also a diurnal variation in PEFR of more than 20% w/ twice daily readings, more than 10%
suggest a diagnosis of asthma.
- other diagnostic test for asthma
inhaled methacholine or histamine
inhaled mannitol
exercise or cold air challenge
positive skin test allergen increases probability of dx of asthma
FeNO-increases w/ airway inflammation. normall 25 ppb in adults
- Challenges in the differential diagnosis of asthma
kids younger than 5 older children and adults elderly cough variant asthma sick building syndrome distinguishing asthma from COPD
- clinical manifestations of asthma
bronchoconstriction
excessive bronchial secretions
- Vitals seen w/ asthma
increased RR, HR, and BP.
pulsus paradoxus: decreased blood pressure during insp. increase blood pressure during exp.
- Physical exam finding w/ asthma
accessory muscle use, insp and exp pursed lip breathing substernal intercostal retractions barrel chest cyanosis cough and sputum production
- Chest assessment finding w/ asthma
expiratory prolongation I:E ratio > 1:3 decreased tactile fremitus and vocal fremitus hyperresonant percussion note diminished BS and heart sounds wheezing and crackles
- sputum examination
eosinophilia
charcot-leyden crystals
cast of mucus from small airways ( kirschman spirals)
IgE level (elevated w/ extrinsic asthma)
- Chest radiograph
increased anteroposterior diameter
translucent or dark lung fields
depressed or flattened diaphragm
could appear normal
- Primary management of asthma
attain and maintain control of clinical manifestations
maintain normal activity levels
maintain pulmonary function as close to normal as possible
prevent asthma exacerbations
avoid adverse effects from asthma medication
prevent asthma mortality
- Components of asthma management
component 1: develop PT/DR relationship
component 2: identify and reduce exposure to risk factors
component 3: assess, treat, monitor asthma
component 4: manage asthma exacerbations
component 5: special considerations
- treating to achieve control
notion of step therapy
- Primary therapies for asthma exacerbations
repetitive administration of rapid acting inhaled bronchodilators
early introduction of systemic glucocorticosteroids
oxygen therapy
continuous neb of short acting beta 2 agnosit in status asthmaticus
- primary goal of treatments is to
relieve airflow obstruction and hypoxemia as quickly as possible, and to plan the prevention of future exacerbations
- component 5 special considerations
pregnancy, obesity, surgery, rhinitis, sinusitis, nasal polyps, occupation, resp infection, gerd, aspirin induced asthma, anaphylaxis and asthma
- ultra short acting bronchodilator agents
epinephrine/ adrenalin
racemic epinephrine
- short acting beta 2 agents or SABA’s
albuterol , metaproterenol, levalbuterol
- systemic corticosteroids
methylprednisolone and hydrocortisone
- Long acting beta 2 agents or LABA’s
Salmeterol
- leukotriene inhibitors
zafirlukast, montelukast, zilueton
- monocional antibody
omalizumab
- xanthine derivatives
theophylline, oxtriphylline, aminophylline, dyphlline
- status asthmaticus
severe asthma unresponsive to repeated courses of beta-agonist therapy, ie inhaled albuterol, levalbuterol, or SQ epinephrine, MEDICAL EMERGENCY
% of acute severe asthma (SA) PT’s that also have a resp tract infection
50%
stage one SA
resp alkalosis, decrease PaCO2, normal PaO2,
asthma exacerbation
stage two SA
resp alkalosis,even more decrease In PCO2,decrease O2 common ED finding
stage three SA
normal PH, normal PaCO2, even more decreased PaO2 impending failure
stage four SA
resp acidosis, increase PaCO2, extreme decrease PaO2
impending resp arrest
resp acidosis, increase PaCO2, extreme decrease PaO2
impending resp arrest