Restrictive/Obstructive Lung Disorders
Restrictive: lung volumes are reduced & the person has difficulty inhaling (RPD)
Obstructive: airway resistance increases & people have difficulty exhaling (OPD)
Intrinsic Factors
tissues between alveoli & capillaries become inflamed, enlarged & fibrotic. The fibrosis increases the elastic recoil of the lungs & makes the lungs less compliant. This leads to difficulty in inhaling, & a reduced inspiratory volume. Fibrosis = scarring @ the alveolar-capillary membrane reducing gas diffusion
Extrinsic factors
inspiratory lung volumes are reduced due to physical deformities/impairments or lack of neural stimulation of the resp. muscles to inhale
Restrictive Pulmonary Disorders:
Chronic Intrinsic: interstitial lung diseases- asbestosis, sarcoidosis, silicosis
Extrinsic: Neuromuscular diseases- muscular dystrophies, motor neuron disease., Chest wall diseases- kyphoscoliosis., obesity, pleural disorders- pneumothorax, pleural effusion
Acute Intrinsic: Pulmonary oedema, infectious, aspiration pneumonia
Obstructive Pulmonary Disorders
Chronic Obstructive Pulmonary Disease (COPD): chronic bronchitis, emphysema, asthma, cystic fibrosis, bronchiectasis
Emphysema
Becomes extremely difficult to exhale
Causes: Irritants (fags) causes breakdown of elastic tissue. Alpha-1 antitrypsin deficiency (protein that protects the elastic tissue in the lungs)
Air becomes trapped inside the lungs. Lungs become hyper inflated = increased lung volume & decreased SA for gas exchange
Early Stages: skin stays pink & healthy as pt. can over ventilate & maintain relatively normal blood gases
Enlargement of air spaces distal to the terminal bronchioles, with breakdown of alveolar walls & loss of elastic recoil of the lungs
Late Stages: elastin in walls of alveoli breakdown = chronic reduction of blood O2 levels (hypoxaemia), increased levels of arterial CO2 (hypercapnia), decreased levels of O2 @ tissue level (hypoxia)
Emphysema: Signs & Symptoms
Subjective Symptoms: Breathlessness- late onset. Anxiety, Fatigue, Loss of appetite
Objective Signs:
Hypoxaemia/Hypoxia (cyanosis, tachycardia, decreased mental judgement, decreased motor proficiency)
Cough (no expectoration)
Tendency to bend forward
Pursed lip breathing
Loss of muscle mass
Weight loss
Barrel chest
Chronic Bronchitis
Major cause- Cigarette smoke. Clinically defined by productive cough for 3 mnths, over 2 consecutive yrs, with a - chest x-ray
40-50% lifelong smokers develop COPD.
Exists where there's chronic inflammation of the lower airways characterized by: hypertrophy of mucous secreting glands, excessive secretion of mucus, recurring chest infections, which progress to narrowing of airways & obstruction of airflwo
Objective Signs: crackles & wheezing, inspiratory stridor, productive cough, large amounts of sputum (especially in the morning), cyanosis of tongue, lips, nail beds, ears, cheeks.
Subjective Symptoms: early onset of breathlessness, anxiety, fatigue, sleep disturbance, nausea, loss of appetite
Pulmonary Heart Disease
Disease causing damage to the lung tissue which in turn causes high BP in the pulmonary arteries (pulmonary HTN) causing back pressure on the right side of heart
Symptoms= leg oedema, distended neck veins, finger clubbing, liver/chest pain, fainting/fatigue, excessive coughing
Hypoxic pulmonary vasoconstriction (pulmonary arteries constrict in the presence of chronic hypoxia causing restriction of blood flow & a back pressure on the right side of the heart
Enlargement & failure of the right ventricle due to vascular changes in the lungs brought about by: