Class 8 - Respiratory 4 Flashcards
Pneumothorax
Defect in visceral pleura or chest wall causing air or gas accumulation in pleural cavity
Result of pneumothorax
Collapse of lung (atelectasis)
Primary/secondary pneumothorax causes
Primary: idiopathic
Secondary: COPD, CF, lung pathologies
Pneumothorax Incidence and Risk factors
- men 5 more likely (any age)
- smoking
- iatrogenic or non-iatrogenic trauma
Pneumothorax Pathogenesis
- Air enters pleural cavity
- Pleura separation destorys negative pressure and lung collapses towards hulum
- Mediastinal shift towards unaffected side which compresses opposite lung
Spontaneous Pneumothorax
Due to blebs and bullae or due to TB, lung abscess or other lung disease
Traumatic Pneumothorax
occurs following penetrating or non-penetrating chest trauma (rib fracture, stab, bullet)
Iatrogenic Pneumothorax
occurs during medical procedure (biopsy, CPR, etc.) – is considered to be traumatic
Open pneumothorax
traumatic type that occurs when air is drawn into lungs upon inspiration and forced out upon expiration
AKA Sucking chest wound
Tension pneumothorax
Significant respiratory impairment or issues with blood circulation. This is a medical emergency.
Pneumothorax clinical manifestation
dyspnea, sharp chest pain, low blood pressure or weak pulse, techypenia, tracheal devation
Pneumothorax diagnosis
History, chest films
Pneumothorax treatment
Oxygen, defect repair, chest tube, asherman seal, watch and wait to heal, pleurodesis (remove pleural cavity - cause it to scar together)
Pneumothorax Prognosis
Good, recurrence likely
Pleurisy aka pleuritis
- Inflammation of pleura caused by infection (viral), injury, tumour
- can be idiopathic
Pleurisy clinical manifestation
- Sudden development
- pain while breathing, cough
- cough, fever, sob, tachypnea
Pleurisy treatment
- aspirin, nsaids, antibiotics
- thoracentesis if effusion present - take fluid out
Pleural effusion
Increased fluid (blood, pus, serous fluid, urine) b/w visceral and parietal pleura
Pleural effusion pathogenesis
- secondary to pathologies causing pleural edema
- Increased secretion of fluid or decreased drainage (CHF, kidney/liver disease, malignancy, etc..)
Pleural effusion clinical manifestation
Depends on fluid amount, degree of lung compression, heart condition
Pleural Effusion diagnosis and treatment
Diagnosis: history, imaging, biopsy
Treatment - may not be required - maybe drainage
Prognosis depends on underlying disease
Ventilatory failure
Secondary to alveolar hypoventilation
(gas not exchanged properly in lungs)
Ventilatory failure conditions can affect?
- mechanical respiration
- lung circulation
- airways
- gas exchange
Ventilatory failure Neural control of respiration
- Respiratory centers in the brainstem have chemoreceptors to
measure the content of carbon dioxide - Brainstem lesions can depress spontaneous breathing
Ventilatory failure respiratory muscles
Can become dysfunctional under several conditions – affect nerves, NMJ, or muscles themselves
Poliomyelitis
VENTILATORY FAILURE
Respiratory muscles
Affects the spinal cord can cause respiratory paralysis
Spinal Cord Injury
VENTILATORY FAILURE
Respiratory muscles
Damages the nerves
Tetanus toxin
VENTILATORY FAILURE
Respiratory muscles
muscle spasm
Myasthenia gravis
VENTILATORY FAILURE
Respiratory muscles
affects the NMJ to cause depression in breathing
Muscular dystrophy
VENTILATORY FAILURE
Respiratory muscles
esp. in duchennes – causes muscle wasting and respiratory muscle failure
VENTILATORY FAILURE
Chest wall lesions
- Restrict lung expansion during inspiration
- Due to deformities of chest cage (kyphoscoliosis), pleural fibrosis, pleural tumours, extreme obesity
VENTILATORY FAILURE
Airway pathologies
E.g. CF (with bronchial mucus plugs), COPD, asthma,
etc.
Acute respiratory distress syndrome
ARDS
Changes that occur in the lungs that cause acute
respiratory failure
ARDS Causes
- Shock - trauma, burns
- Pneumonia
- Toxic Lung injury - fumes, drugs
- Aspiration of fluids (drowning)
ARDS Etiology and Pathogenesis
- Can result from various conditions
- Involves injury to endothelial cells in pulmonary capillaries or alveolar lining cells
- Affects alveolar walls, severely impairing gas exchange
- Leads to hypoxia due to poor blood oxygenation
- Untreated cases may cause fatal systemic issues like shock, sepsis, SIRS, or respiratory acidosis
- Associated with systemic inflammatory response syndrome (SIRS)
LUNG CANCER
AKA bronchogenic carcinoma
- A malignancy of the respiratory tract epithelium
- Most cases of lung cancer are primary tumors
Lung Cancer epidemiology
- Leading cause of cancer death globally for both men and women
- One of the top preventable causes of death worldwide
- Causes more deaths than colon, breast, and prostate cancers combined
- Up to 90% of cases linked to cigarette smoking
- Typically diagnosed after age 50
- Five-year survival rate is 10-15%, as half of cases are stage IV at diagnosis
Lung Cancer Etiology and Risk Factors
Cigarette smoking (especially over 20 per day)
Occupational and environmental exposures
Industrial living
Age and family history
Asbestos and radon gas exposure
Small cell lung cancer (SCLC)/Oat Cell
- Small cell lung cancer (SCLC) accounts for 20% of all lung cancers
- Highly aggressive and predominantly occurs in smokers
- Rapid growth; about 60% of patients have metastatic disease at diagnosis
- Small cell cancer can also occur in non-lung tissues (e.g., cervix, prostate)
Non-small cell lung cancer (NSCLC)
- Non-small cell lung cancer (NSCLC) accounts for 80% of all lung cancers
- Types include squamous cell carcinoma, adenocarcinoma (most common), and large cell carcinoma
- Most lung cancers in non-smokers are NSCLC
- Clinical behavior varies by histologic type; around 40% of cases show metastatic disease at diagnosis
Lung Cancer Pathogenesis 1
- Tobacco smoke contains various chemicals that act as primary carcinogens
- DNA-mutating agents activate oncogenes, deactivate tumor suppressor genes, and mutate genes involved in detoxification (oxidative stress) and DNA repai
Lung Cancer Pathogenesis 2
- Lung cancer is highly invasive and metastasizes early
- It spreads to the mediastinum, pleural cavity, and lymph nodes
- Distant metastasis commonly occurs to the liver, brain, bones, kidneys, and adrenal glands
LUNG CANCER
Clinical Manifestation 1
- Local tumor extension into the mediastinum or pleural cavity can cause mass effect
- Leads to obstruction, resulting in atelectasis and lung infection
- Can cause pleural effusion
- Progressive dyspnea due to lung compression
- May cause pain and paralysis of diaphragm and vocal cord muscles
Lung Cancer Clinical Manifestation 2
- Hemoptysis
- Cachexia
- Shortness of breath (SOB)
- Cough
- Anorexia
- Paraneoplastic syndromes
- Digital clubbing
Lung Cancer clinical manifestation 3
- Liver: Causes hepatomegaly
- Brain: Leads to neurologic symptoms and high mortality
- Bone: Results in fractures and pain
- Adrenal glands: Affected by metastasis as wel
LUNG CANCER
Management
- Diagnosis: Chest x-ray and biopsy (most reliable)
- CT scans: 95% false positive rate
- Treatment: Surgery, chemotherapy, and radiation
- Prognosis: Very poor
- Prevention: Crucial for reducing risk
