370: Respiratory Patho/Pharm Flashcards
The maximum amount of additional air that can be drawn into the lungs by determined effort after normal inspiration
Inspiratory reserve volume (IRV)
The volume of air present in the lungs at the end of passive expiration
Functional Resodual Capacity (FRC)
The lung volume representing normal volume of air displaced between normal inhalation and exhalation when extra effort is not applied
Tidal Volume (TD)
Amount of air that remains in a person’s lungs after fully exhaling
Residual Residual (RV)
Amount of air that can be inhaled after the end of normal expiration
Inspiratory Capacity (IC)
Maximal volume of air, usually 1000mL, that can be expelled from lungs after normal expiration
Expiratory Reserve Volume (ERV)
Measure of maximum air that can be inhaled or exhaled during a respiratory cycle.
Equals the sum of expiratory reserve volume (ERV) + tidal volume (TV) + inspiratory reserve volume (IRV)
Vital Capacity (VC)
Inspiratory Capacity plus the functional residual capacity (the volume in lungs after a maximal inspiration)
Total Lung Capacity (TLC)
= Vital Capacity (VC) + Residual Volume (RV)
Amount of air a person can exhale during a forced breath
Forced Expiratory Volume (FEV)
During first second = FEV1
Third second = FEV3
Total amount of air exhaled during the FEV test
Forced Vital Capacity (FVC)
What is the V/Q ratio?
Ventilation-perfusion ratio
V = air going in to alveoli
Q = blood sent to lungs (perfusion)
What would cause a low V/Q ratio?
- Impaired ventilation
- Leads to hypoxemia
Asthma, pneumonia, pulmonary edema
What constitutes a shunt (very low) V/Q ratio?
Blocked ventilation from collapsed alveolus
Severe bronchial restrictions, atelectasis, consolidation, pulmonary edema, pneumonia
What constitutes high V/Q?
Impaired perfusion, but ventilated (Alveolar dead space)
Ex. Pulmonary embolus
What are the 3 pulmonary obstructive diseases?
- Asthma
- Chronic bronchitis
- Emphysema
Chronic bronchitis + emphysema = COPD
What are clinical manifestations of pulmonary obstructive disease?
- Increased WOB
- V/Q mismatch
- Decreased FEV1
- Wheezing
- Dyspnea
What disorder causes bronchial hyper-responsiveness, construction of airways, and variable airflow obstruction that is reversible
Asthma
What are clinical manifestations of asthma?
- Tachycardia, tachypnea, low SpO2
- Wheezing, non-productive coughing, prolonged expiration
- SOB, tightness in chest or pain, dyspnea
- Increased WOB
- Pulse paradoxus (disappears during resp cycle)
- Diaphoresis, tripoding, anxious, altered LOC
What is Status asthmaticus?
Bronchospasmr not reversible by usual measures
Life threatening!
1. Silent Chest
2. PaCO2 > 70mmHg
How is asthma managed?
- Oxygen
- Inhaled beta-agonist bronchodilators (ex. Salbutamol)
- Corticosteroids
- Ipratropium bromide (bronchodilator)
- Educate over allergens and irritants
What pulmonary disease is largely caused by smoking?
COPD
What pulmonary disease is characterized by progressive, irreversible airway obstruction
Chronic Obstructive Pulmonary Disease (COPD)
What are 6 risk factors of COPD?
- Tobacco smoke
- Occupational dusts and chemicals
- Outdoor air pollution
- Indoor air pollution (biomass fuel for cooking and heating)
- Effects of lung growth during gestation and childhood
- Genetics (alpha1 antitrupsin gene)
What is the pathogenosis of COPD?
- Inflammation, edema, and fibrosis of bronchial wall
- Hypertrophy of submucosal glands with hypersecretion of micos
- AIRFLOW OBSTRUCTION
- Loss of elastic lung fibers
- Impairs lung to recoil, results in airway collapse
- Loss of alveolar tissue
- Decrease SA for gas exchange
What would be the V/Q ratio in a person with COPD?
Low V/Q
Inflammation and excess mucus secretion obstruct airflow
Why are lungs in COPD patients hyperinflated?
Mucus plugs in combination. With narrowed airways
- Air trapped in alveoli
- Dec elastic recoil of bronchial wall
- Airways start to collapse
- Increased WOB and hyper expansion of chest
What pulmonary disease is due to hypersecretion of mucus and chronic productive cough that lasts at least 3 mi this of the year and for at least 2 consecutive years?
Chronic bronchitis
What is the Pathophysiology of chronic bronchitis?
- Inspired irritants increase mucous production, size, and number of mucous glands (mucus thicker than normal)
- Bronchial edema
- Hypertrophied bronchial smooth muscle
- Hypoxemia and Hypercapnia (d/t ineffective resp)
- Airways collapse early in expiration, trapping gas in lung
What differentiates chronic bronchitis from asthma?
A productive cough
What are the clinical manifestations of chronic bronchitis?
- Productive cough
- Wheezing, SOB
- Decreased exercise tolerance
- Decreased FVC, FEV1
- Increased FRC, RV
- Polycythemia, cyanosis, clubbing
- Pulmonary HTN
How is chronic bronchitis managed?
- Smoking cessation (halts progression)
- Bronchidilators
- Expectorants
- Chest physio
- Antibiotics
- Steroids
- Mechanical ventilation
- Oxygen therapy
What are the 4 respiratory defence mechanisms?
- Naso-pharyngeal defences (lysosomes and IgA)
- Glottic and cough reflexes
- Mucociliary blanket
- Pulmonary macrophages (final defence)
