Medical Terminology – Chapter 7: The Respiratory System

Functions of the Respiratory System

• Air conduction to lungs; gas exchange (supply \text{O}2, remove \text{CO}2/H_2O)
• Acid–base & speech production (airflow through larynx)

Anatomy Overview

• Upper tract: nose (septum, cilia, mucus, olfactory receptors), mouth, pharynx (naso-, oro-, laryngo-), epiglottis, larynx (vocal cords, thyroid cartilage), trachea
• Paranasal sinuses: frontal, sphenoid, maxillary, ethmoid – lighten skull, resonance, mucus
• Lower tract: bronchial tree → bronchi → bronchioles → alveoli (surfactant ↓ surface tension)
• Lungs: R 3 lobes; L 2 lobes + cardiac notch
• Mediastinum: heart, great vessels, esophagus, trachea, bronchi, thymus, lymph nodes
• Pleura: parietal (thoracic wall), visceral (lung); pleural cavity – fluid lubrication
• Diaphragm (phrenic nerve) – principal muscle of ventilation

Physiology: Respiration

• Inhalation: diaphragm contracts ↓; Exhalation: relaxes ↑
• External respiration: lung alveoli ↔ blood
• Internal (cellular) respiration: blood ↔ tissues

Key Pathologies

• COPD = chronic bronchitis + emphysema; smoking; irreversible airflow obstruction
• Asthma: reversible bronchial inflammation, bronchospasm, mucus → wheeze
• URIs/common cold (acute nasopharyngitis); influenza; RSV; pertussis
• Pharyngitis, laryngitis (voice loss), croup, epistaxis
• Acute bronchitis; bronchiectasis (permanent dilation); bronchorrhea (↑ mucus)
• Pleural disorders: pleurisy, pleural effusion, pyothorax, hemothorax, pneumothorax
• Lung disorders: ARDS, atelectasis, granuloma, pulmonary edema/embolism, TB, pneumonias (bacterial, viral, aspiration, CAP, mycoplasma, PCP), interstitial lung diseases (pulmonary fibrosis, pneumoconiosis), cystic fibrosis, lung cancer
• Breathing pattern terms: eupnea, apnea, bradypnea (
• Sleep apnea; expectoration (hemoptysis)
• Oxygenation issues: airway obstruction, anoxia, hypoxia, hypoxemia, hypercapnia, cyanosis, respiratory failure
• SIDS: unexplained infant death (1 mo–1 yr), back-sleeping reduces risk

Diagnostics

• Observation: respiratory rate, sounds (rales, rhonchi, stridor)
• Imaging/visualization: CXR, bronchoscopy, laryngoscopy
• Lung function: PFTs (spirometer), peak-flow meter, polysomnography (sleep study)
• Pulse oximeter (SpO_2), sputum studies (cytology, C&S)
• TB tests: Mantoux PPD skin test, blood assays; positive → CXR, sputum

Treatments & Therapies

• Drugs: antitussive, decongestant, expectorant, bronchodilator; inhaled corticosteroid (controller)
• Delivery: metered-dose inhaler, nebulizer
• Airway procedures: endotracheal intubation, tracheostomy/tracheotomy, laryngotomy, septoplasty, endoscopic sinus surgery
• Thoracic surgery: pneumonectomy, lobectomy, wedge resection, thoracentesis, thoracotomy, VATS
• Respiratory support: CPAP, BiPAP, Ambu® bag (BVM), ventilator
• Oxygen therapy: nasal cannula, rebreather/non-rebreather mask, hyperbaric oxygen (HBOT)

Key Abbreviations

• ARDS – Acute Respiratory Distress Syndrome
• COPD – Chronic Obstructive Pulmonary Disease
• CF – Cystic Fibrosis
• PNA – Pneumonia
• TB – Tuberculosis
• URI – Upper Respiratory Infection
• RSV – Respiratory Syncytial Virus
• SIDS – Sudden Infant Death Syndrome