respiratory

Step 12: Respiratory System

• Definition and Importance

  • A pulmonologist is a physician specializing in the respiratory system.

  • The respiratory system is crucial for bringing oxygen into contact with the bloodstream in the lungs.

  • The human body cannot survive without oxygen for more than three to five minutes.

  • Respiratory arrest (failure of lungs) and cardiac arrest (failure of the heart) can both lead to death.

Components of the Respiratory System

• Anatomy

  • The respiratory system consists of air passages, pulmonary vessels, lungs, and breathing muscles.

    • Upper Airways:

      • Nose, mouth, pharynx (muscular tube).

  • Air Passage Flow:

    • Air enters through the upper airway, moves through the pharynx, and into the larynx (voice box).

    • The epiglottis prevents food and water from entering the respiratory tract.

    • Air continues into the trachea, which splits into bronchi—leading to the right and left lungs.

  • Lung Structure:

    • Each lung has branching tubes that terminate in alveoli (tiny air sacs) where gas exchange occurs.

Functions of the Respiratory System

• Gas Exchange

  • Oxygen enters and carbon dioxide exits the bloodstream in the alveoli via tiny vessels.

• Ventilation (Breathing):

  • Inhaling (Inspiration):

    • Diaphragm contracts downward, causing the lungs to fill with air.

  • Exhaling (Expiration):

    • Diaphragm relaxes upward, forcing air out of the lungs.

  • Normal breathing occurs spontaneously 12-20 times per minute, moving about a pint of air each time.

Respiratory System Terminology

• Combining Forms and Abbreviations:

  • alveoli/alveolus: air sac

  • pharyng/o: pharynx, throat

  • ARDS: acute respiratory distress syndrome

  • phon/o: voice, sound

  • bronch/o: bronchus

  • phren/o: diaphragm, mind

  • bronchiol/o: bronchiole

  • pleur/o: pleura, rib

  • capn/: carbon dioxide

  • pneum/o: air, gas, lung

  • COPD: chronic obstructive pulmonary disease

  • pulm/o, pulmon/o: lung

  • CPR: cardiopulmonary resuscitation

  • RDS: respiratory distress syndrome

  • CXR: chest x-ray

  • rhin/o: nose

  • DTaP: diphtheria, tetanus and pertussis

  • RLL: right lower lobe (of lung)

  • FEV: forced expiratory volume

  • RT: respiratory therapist

  • ICU: intensive care unit

  • RUL: right upper lobe (of lung)

  • IN: inhalation

  • SCLC: small cell lung cancer

  • laryng/larynx: voice box

  • SOB: shortness of breath

  • LLL: left lower lobe (of lung)

  • spir/o: breathe

  • LUL: left upper lobe (of lung)

  • T&A: tonsils and adenoids

  • MDI: metered-dose inhaler

  • TB: tuberculosis

Page 2: Respiratory Disorders and Impacts

• Pathogen Exposure

  • Each breath can carry microorganisms (viruses and bacteria) that can impact respiratory health.

  • Most microorganisms are harmless, but some can cause serious respiratory illnesses.

• Common Respiratory Illnesses:

  • Upper Airway Conditions:

    • Common cold: affects only upper airways.

  • Lower Respiratory Diseases:

    • Bronchitis: inflammation of the bronchi.

    • Pneumonia: infection inflaming air sacs in lungs.

• Chronic Conditions:

  • Emphysema:

    • Alveoli enlarge, destroying walls and capillaries, leading to breathing difficulties and low blood oxygen.

  • Asthma:

    • Airways narrow and swell, producing excess mucus—causing wheezing and shortness of breath.

  • Lung Cancer:

    • Growth of abnormal cells in lungs, caused by irritants (cigarette smoke, asbestos, radiation).

    • Begins as a tumor in bronchi, leading to pain, coughing, and difficulty breathing.

    • Survival rates are improving with new therapies.