Pulm exam 1 Flashcards
(227 cards)
GINA definition of asthma
chronic airway inflammation; history of respiratory sx (wheeze, sob, chest tightness, cough) that vary over time and in intensity, together with variable expiratory airflow
What term defines wheezing, breathlessness, chest tightness, and coughing
obstruction (typically occurs at night or in the early morning)
All asthma patients are at risk for acute severe disease, you want to treat underlying airway inflammation with what two steps
control asthma
reduce asthma-associated risk
What is the most common chronic disease among children
asthma
What are the 3 predictors for persistent adult asthma
atopy (hypersensitivity to environmental allergens, type 1 allergic rxn with IgG antibody and asthma)
onset during school age
presence of bronchial hyperresponsiveness (BHR)
The severity of asthma in childhood is the predictor of severity in adulthood
true
How does genetic factors affect asthma
strong risk factor for offspring
risk increased with FH of atopy
How does enviornmental factors affect asthma
secondhand smoke exposure increase risk
outdoor pollutants
exposure to specific allergens in the workplace (late in life)
How does obesity affect asthma
child: risk factor for asthma especially girls
adult: risk factor for asthma
How does adult-onset asthma affect people
atopy
nasal polyps
aspirin sensitivity
occupational exposure
recurrence of childhood asthma
Pathophysiology of asthma
inhaled allergens are taken up by antigen presenting cells (t cells) activate Th2 response, b cell production of IgE and pro-inflammatory cytokines and chemokines, activation of eosinophils, neutrophils, alveolar macrophages
What is the early phase response to asthma
activation and degtanulation of mast cells and basophils
acute bronchoconstriction that lasts over 1 hour after exposure
What is the late phase response to asthma
activated airway cells release inflammatory cytokines and chemokines causing more inflammation
increased airwat inflammation and hyperresponsivness that occure 4-6 hours after initial allergen challenge
What is airway inflammation (chronic; although symptoms are intermittent)
T-lympohcytes release cytokines which cause eosinophilic infiltration, IgE production by B-lymphocytes
mast cells infiltrate airway smooth muscle and broncial epithelium causing mucous gland hyperplasia and mast cell degranulation (develop pro-inflammatory mediator, AHR and airway remodeling)
What is airway hyper responsiveness (AHR)
exaggerated ability of airways to narrow in response to stimuli
related to airway inflammation and structural airway changes
How does airway smooth muscle construction cause airway obstruction
-tone maintained by sym, parasym, and non-adrenergic
-constriction results form mediators like histamine and prostaglandins
How does airway edema cause airway obstruction
-inflammatory mediators (histamine, leukotriene, bradykinin) will increase microvascular permeability causing edema
-rigid airway limit air flow
How does mucus hyper secretion cause airway obstruction
increase number and volume of mucous glands
How does airway remodeling cause airway obstruction
some pt will have fixed obstruction
characterized by epithelial damage, subepithelial fibrosis, airway smooth muscle hypertrophy, increase mucous production/vascularity of airways
Range of clinical presentation and diagnosis
normal pulmonary function with symptoms only during acute exacerbation to significantly decreased pulmonary function with continuous symptoms
History of clinical presentation and diagnosis
FH, SH, precipitating factors, exacerbations, development of symptoms, treatment
Symptoms of asthma
defining: wheezing, sob, chest tightness, coughing (worse at night)
-anxious/agitated
-mental status change lead to respiratory failure
-presence of precipitating factors
Signs of asthma
tachypnea
tachycardia
use of accessory muscles
auscultation (end expiratory wheezes/through inspiration/expiration)
bradycardia and absence of wheezing (respiratory failure)
What are the 5 defining features of lab tests (variable expiratory flow limitation)
spirometry
increase in PEF >20% after bronchodilator
increase IgE
(+) redioallergosorbent test (RAST)
fractional exhaled nitric oxide (FeNO) use when clinical course and spirometry is unclear