Specialty Hub
Fundamentals
Before the ventilators and the drips, the lungs. This is the physiology every respiratory therapist builds on — how air moves and gas is exchanged, how the body controls each breath, and how to read a chest at the bedside. Get these right and every other specialty gets easier.
Guides
The core science — anatomy, gas exchange, V/Q, control of breathing, and the bedside exam.
Breath Sounds & Lung Auscultation
A systematic approach to lung auscultation — the listening sequence, normal vesicular and bronchial sounds, and an adventitious-sounds table covering crackles, wheezes, rhonchi, stridor, and pleural rubs with their mechanisms and causes.
Respiratory System Anatomy & Physiology
How the respiratory system is built and how it moves air: the conducting and respiratory zones, the alveolar-capillary membrane and surfactant, the pleura, the muscles of ventilation, and the pressures that drive every breath.
Gas Exchange & Oxygen Transport
How oxygen moves from alveolus to mitochondria: diffusion across the alveolar-capillary membrane, the oxyhemoglobin dissociation curve and its shifts, oxygen content and delivery, and how carbon dioxide is carried back.
Ventilation-Perfusion (V/Q) Matching
Why matching airflow to blood flow is the key to gas exchange: the normal V/Q ratio and its regional gradient, dead space versus shunt, hypoxic pulmonary vasoconstriction, and the five mechanisms of hypoxemia.
Control of Breathing
How the body regulates ventilation breath to breath: the medullary and pontine centers, central and peripheral chemoreceptors, the dominant role of CO₂ and pH, and the hypoxic drive that matters in chronic CO₂ retention.
Respiratory Patient Assessment
A systematic bedside respiratory assessment: history and the cardinal symptoms, then inspection, palpation, percussion, and auscultation, plus the vital signs and work-of-breathing signs that flag a deteriorating patient.
Interactive Practice
Practice Tools
Put the physiology to work — alveolar gas, the A-a gradient, minute ventilation, oxygenation, and the full blood-gas picture.
Clinical References
Lung volumes and the bedside-assessment numbers, ready to scan.
Breath Sounds Quick Reference
A bedside reference for normal and adventitious breath sounds — vesicular, bronchovesicular, and bronchial sounds plus crackles, wheezes, rhonchi, stridor, and pleural friction rub — with timing, quality, and common causes.
Lung Volumes & Capacities
A reference to the four lung volumes and four capacities - tidal volume, IRV, ERV, and RV, and the IC, FRC, VC, and TLC they combine into - with typical adult values and what each one means clinically.
Respiratory Assessment Quick Reference
A bedside lookup for respiratory assessment - normal vital sign and respiratory-rate ranges, percussion notes, tactile fremitus and tracheal-deviation patterns, the combined exam findings for common conditions, and the work-of-breathing red flags that signal deterioration.
Quick Charts
Oxygen unloading and the causes of hypoxemia, side by side.
Oxyhemoglobin Dissociation Curve Shifts
A side-by-side chart of left versus right shifts of the oxyhemoglobin dissociation curve - the causes, the effect on P50 and on hemoglobin affinity for oxygen, and the clinical meaning - with the key PaO₂-to-SaO₂ landmarks.
Five Causes of Hypoxemia
The five mechanisms of hypoxemia compared side by side - V/Q mismatch, shunt, hypoventilation, diffusion limitation, and low inspired oxygen - with the A-a gradient, the response to supplemental oxygen, and typical examples.
Suggested Learning Path
From the anatomy of a breath to reading a chest.
Related Specialties
Fundamentals feed directly into these areas.