Primary function of respiratory system
Transport oxygen from air to blood and carbon dioxide from blood to air
Upper respiratory tract
Includes nasal cavity pharynx and larynx warms moistens and filters air
Lower respiratory tract
Includes trachea bronchi bronchioles and alveoli and is the main site of gas exchange
Alveoli
Thin walled air sacs lined with simple squamous epithelium and surfactant where gas exchange occurs
Surfactant
Substance reducing surface tension to keep alveoli inflated
Ventilation
Movement of air into and out of lungs driven by pressure gradients
Boyles law in breathing
Air moves from high pressure to low pressure during inspiration and expiration
Tidal volume
Amount of air exchanged in normal breathing
Vital capacity
Maximum air that can be inhaled and exhaled with forced breathing
Residual volume
Air remaining in lungs after maximum expiration
Central chemoreceptors
Located in medulla detect CO2 and pH changes
Peripheral chemoreceptors
Located in carotid bodies detect oxygen carbon dioxide and pH changes
Hypercapnia
Increased carbon dioxide causing respiratory acidosis and increased respirations
Hypocapnia
Low carbon dioxide usually from hyperventilation causing respiratory alkalosis
Hypoxemia
Low oxygen level in blood stimulating respiratory drive
Gas exchange mechanism
Gases diffuse across respiratory membrane based on partial pressure gradients
Ventilation perfusion ratio
Matching of airflow and blood flow required for efficient gas exchange
Spirometry
Pulmonary function test measuring lung volumes and airflow
Arterial blood gas test
Measures oxygen carbon dioxide bicarbonate and blood pH
Pulse oximetry
Measures oxygen saturation in blood
Bronchoscopy
Visual examination of airways allowing biopsy and identification of bleeding or lesions
Sputum culture
Identifies respiratory pathogens and antibiotic sensitivity
General respiratory disease manifestation cough
Protective reflex removing irritants from airways
Dyspnea
Subjective sensation of difficult or uncomfortable breathing
Cyanosis
Bluish discoloration due to increased deoxygenated hemoglobin
Rales
Crackling breath sounds from fluid in alveoli
Rhonchi
Low harsh sounds caused by thick mucus in airways
Stridor
High pitched sound indicating upper airway obstruction
Hemoptysis
Coughing up blood tinged sputum
Common cold cause
Viral infection transmitted by respiratory droplets
Common cold treatment
Supportive care antivirals and prevention through hygiene
Sinusitis cause
Usually bacterial infection of sinus cavities
Sinusitis treatment
Analgesics and antibiotics if bacterial
Epiglottitis cause
Bacterial infection causing swelling of epiglottis and airway obstruction risk
Epiglottitis key signs
Drooling difficulty swallowing anxiety tripod position
Epiglottitis treatment
Oxygen therapy and antimicrobial drugs
Influenza cause
Highly contagious viral infection with frequent mutation
Influenza manifestations
Sudden fever fatigue body aches cough and possible viral pneumonia
Influenza prevention
Vaccination respiratory hygiene antiviral medications
Bronchiolitis cause
Respiratory syncytial virus infection of small bronchi and bronchioles
Bronchiolitis manifestations
Wheezing dyspnea rapid shallow breathing fever cough
Pneumonia definition
Inflammation of lung tissue with exudate in alveoli impairing gas exchange
Lobar pneumonia cause
Usually Streptococcus pneumoniae producing consolidation in one lobe
Lobar pneumonia sputum
Rust colored sputum due to alveolar exudate
Bronchopneumonia pattern
Diffuse infection in multiple lung areas with purulent sputum
Atypical pneumonia cause
Often Mycoplasma or viral organisms producing milder symptoms
Tuberculosis cause
Mycobacterium tuberculosis transmitted by respiratory droplets
Primary TB
Initial infection often asymptomatic with granuloma formation
Active TB manifestations
Weight loss fever night sweats prolonged productive cough blood sputum
TB diagnosis
Tuberculin skin test sputum culture chest radiograph
TB treatment
Long term combination antibiotic therapy
Cystic fibrosis cause
Genetic disorder producing thick tenacious mucus in lungs pancreas and ducts
Cystic fibrosis lung effect
Mucus obstructs bronchi leading to infections and airflow limitation
Cystic fibrosis diagnosis
Sweat test genetic testing pulmonary tests
Cystic fibrosis treatment
Chest physiotherapy nutritional therapy infection control
Lung cancer major risk
Smoking accounts for about 90 percent of cases
Lung cancer early sign
Persistent cough hemoptysis chest pain
Lung cancer diagnosis
CT scan radiography bronchoscopy biopsy
Lung cancer treatment
Surgery chemotherapy radiation or ablation
Asthma definition
Chronic inflammatory airway disease with hyperresponsive bronchi and reversible obstruction
Extrinsic asthma
Triggered by allergic hypersensitivity reactions
Intrinsic asthma
Triggered by infections stress cold exercise or irritants
Asthma pathophysiology
Bronchoconstriction mucosal edema and thick mucus obstruct airways
Asthma manifestations
Wheezing dyspnea chest tightness tachycardia hypoxia
Status asthmaticus
Severe prolonged asthma attack not responding to treatment and potentially fatal
Asthma treatment
Bronchodilators glucocorticoids avoidance of triggers maintenance inhalers
COPD definition
Group of chronic progressive lung diseases causing irreversible airflow limitation
Emphysema pathophysiology
Destruction of alveolar walls reducing surface area and causing air trapping
Emphysema hallmark
Barrel chest from hyperinflated lungs and flattened diaphragm
Emphysema manifestations
Progressive dyspnea weight loss fatigue prolonged expiration
Chronic bronchitis definition
Productive cough for at least 3 months in 2 consecutive years
Chronic bronchitis pathophysiology
Inflamed thickened bronchi with mucus gland enlargement and fibrosis
Chronic bronchitis manifestations
Chronic productive cough cyanosis dyspnea thick secretions
COPD treatment
Smoking cessation bronchodilators vaccines oxygen therapy rehabilitation
Pulmonary edema
Fluid accumulation in alveoli reducing oxygen diffusion and lung expansion
Pulmonary edema signs
Cough orthopnea frothy sputum hypoxemia cyanosis
Pulmonary embolus
Obstruction of pulmonary artery usually from deep vein thrombosis
Pulmonary embolus signs
Sudden dyspnea chest pain tachycardia anxiety hypoxia
Pulmonary embolus prevention
Anticoagulants early ambulation compression stockings
Infant respiratory distress syndrome
Caused by surfactant deficiency in premature infants leading to alveolar collapse
Infant RDS signs
Rapid shallow breathing cyanosis frothy sputum decreased breath sounds
Infant RDS treatment
Synthetic surfactant oxygen CPAP ventilation support
Adult respiratory distress syndrome
Acute inflammatory lung injury causing fluid leakage surfactant damage and severe hypoxia
ARDS manifestations
Rapid shallow breathing dyspnea tachycardia respiratory and metabolic acidosis
ARDS treatment
Supportive ventilation and treatment of underlying cause
Acute respiratory failure
Inability of lungs to maintain adequate oxygenation or carbon dioxide removal
Respiratory failure treatment
Treat underlying disorder and provide respiratory support