Chapter 51: Pulmonary Disorders - Asthma Flashcards
increased airway responsiveness and persistent subacute inflammation are associated with polymorphism genes located on which chromosome?
Chromosome 5q
Hallmarks of asthma (4)
- reversible airway obstruction from bronchial smooth muscle contraction 2. vascular congestion 3. tenacious mucus 4. mucosal edema
The following cells are involved in mucosal inflammation except:
a. mast cells
b. B lymphocytes
c. T lymhocytes
d. eosinophils
b. B lymphocytes
True or False: In asthma, FEV1/FVC ratio and PEF are higher.
FEV1 - forced expiratory volume in 1 second
FVC - forced vital capacity PEF - peak expiratory flow
False. In asthma, FEV1/FVC ratio and PEF are lower.
True or False: Alterations in oxygenation primarily reflect ventilation-perfusion mismatching because of uneven distribution or airway narrowing.
True.
Descrbe the 4 Clinical stages of asthma in terms of:
- FEV1
- PO2
- PCO2
This is the amount of air expelled from lungs over 1 minute during a forceful expiration
FEV1
(forced expiratory volume in 1 second)
This is the amount of air that can be forcible exhaled after taking the deepest breath possible.
FVC
(forced vital capacity)
Why is an asthmatic pregnant woman more susceptible to hypoxia and hypoxemia than a normal pregnant woman?
FRC is smaller, and pulmonary shunting is increased.
Effects of pregnancy on asthma
1/3 improves
1/3 unchange
1/3 worsens
Classify the severity of asthma:
- symptoms: 2 days/week
- nocturnal awakenings: once a month
- need for SABA: 2days/week
- no interference with normal activity
- normal lung function between exacerbations
- FEV1: >80%
- FEV1/FVC: normal
intermittent
Classify the severity of asthma:
- symptoms: daily
- nocturnal awakenings: twice a week
- need for SABA: daily
- some limitation
- FEV1: 60-80%
- FEV1/FVC: reduced by 5%
moderate
Characterize mild asthma in terms of:
- symptoms
- nocturnal awakenings
- need for SABA
- limitation
- FEV1
- FEV1/FVC
Characterize severe asthma in terms of:
- symptoms
- nocturnal awakenings
- need for SABA
- limitation
- FEV1
- FEV1/FVC
Intrapartum exacerbation is seen in how many percent of women with mild or moderate asthma?
Two studies:
- Schatz: up to 20%
- Wendel et al: 1%
True or False.
There is an 18-fold increased exacerbation risk following vaginal delivery versus cesarean delivery.
False.
There is an 18-fold increased exacerbation risk following cesarean delivery versus vaginal delivery.
Factors significantly linked to increased morbidity in asthma.
severe disease
poor control
True or False.
For women with severe asthma, the rate of delivery before 37 weeks is increased twofold.
True
Enumerate:
complications of status asthmaticus
- muscle fatigue with repiratory arrest
- penumothorax
- penumomediastinum
- acute cor pulmonale
- cardiac arrhythmias
True or False:
women with moderate to severe asthma, regardless of treatment, are at increased risk of pre-eclampsia.
True
Which of the following is TRUE regarding fetal effects of asthma?
a. Fetal hypoxemia develops well before the alkalosis compromises maternal oxygenation.
b. the fetus is jeopardized by decreased uterine blood flow, increased maternal venous return and an alkaline-induced leftward shift of the oxyheoglobin dissociation curve.
c. fetal growth is unaffected by asthma
d. fetal response to maternal hypoxemia include: increased umbilical blood flow, systemic and pulmonary vascualr resistance and decreased cardiac output
A. is true
Fetal effects of asthma:
- Fetal hypoxemia develops well before the alkalosis compromises maternal oxygenation.
- the fetus is jeopardized by decreased uterine blood flow, decreased maternal venous return and an alkaline-induced leftward shift of the oxyheoglobin dissociation curve.
- c. fetal growth restriction is increases with asthma severity
- d. fetal response to maternal hypoxemia include: decreased umbilical blood flow, increased systemic and pulmonary vascular resistance and decreased cardiac output
Additional information
- monitoring fetal response is an indicator of maternal status
- use of asthma controllers poses slightly greater possibility of teratogenic/advers fetal effects (cleft lip and palate, autism). Half of patients discontinue drugs between 5-13 weeks of gestation
Signs of potentially fatal asthma attack
What diagnostic best measures asthma severity?
Sequential measurement of FEV1 or PEFR
PEFR (peak expiratory flow rate): person’s maximum speed of expiration
Measure of FEV1 which correlates to a severe disease (hypoxia, poor response to therapy, high relapse rate)
FEV1 < 1L
or
FEV1 less than 20% of predicted value
Ideal values of FEV1 and PEFR
FEV1 >80% of predicted
PEFR range: 380-550 L/min
how often should women with moderate to severe asthma measure and record either FEV1 or PEFR?
twice daily
