Lungs and thorax

• Thorax


  Portion of the body extending from the base of the neck superiorly to the level of the diaphragm inferiorly, contains the lower respiratory tract
• Thoracic Cage


  Outer structure of the thorax, composed of sternum, ribs, 12 thoracic vertebrae, muscles and cartilage, provides support and structure
• Thoracic Cavity


  Consist of mediastinum (central cavity containing the trachea, bronchi, esophagus, heart and great vessels), and lungs, lined by pleural membranes

  
• Ribs

  • Ribs 1-7: attached directly to the sternum by costal cartilages, True Ribs
  • Ribs 8-12: not directly attached to the sternum, False Ribs
  • Ribs 8-10: attached to the sternum by a common cartilage
  • Ribs 11-12: not attached at all, Floating ribs
• Muscles of Respiration

  • External Intercostal Muscles: Pulls / elevates the ribs
  • Diaphragm: Prime mover of inspiration
  • Internal Intercostal Muscle: Retracts / depresses the ribs
• Pleura


  Thin, double-layered serous membrane lining the thoracic cavity, the parietal pleura line the chest cavity and the visceral pleura covers the external surfaces of the lungs, the pleural space lies between the two pleural layers
• Lung Lobes

  • Fissures are double folds of pleura that divide the lung into lobes

  
• Anatomic Descriptors of the Chest

  • Supraclavicular: above the clavicles
  • Infraclavicular: below the clavicles
  • Interscapular: between the scapulae
  • Infrascapular: below the scapulae
  • Bases of the lungs: the lowermost portions

  
• Trachea and Bronchi


  The trachea is a flexible structure that lies anterior to the esophagus, begins at the level of the cricoid cartilage in the neck, and is approximately 10 to 12 cm long in an adult, bifurcates into the right and left main bronchi at the level of the sternal angle

  
• Vertical Reference Lines

  • Anterior chest: Midsternal Line, Left Mid-clavicular Line, Right Mid-clavicular Line
  • Lateral Aspect of the Thorax: Mid-axillary Line, Anterior Axillary Line, Posterior Axillary Line
  • Posterior chest: Vertebral (or spinal) line, Right Scapular Line, Left Scapular Line
• Chest Shape and Size

  • In healthy adults, the thorax is oval, its anteroposterior diameter is half its transverse diameter, the overall shape of the thorax is elliptical, in older adults, kyphosis and osteoporosis alter the size of the chest cavity as the ribs move downward and forward

  
• Deformities of the Chest

  • Pigeon chest (pectus carinatum)
  • Funnel chest (pectus excavatum)
  • Barrel chest
  • Kyphosis
  • Scoliosis
• Rhythmic Ventilation

  Normal respiration rate is 12-20 breaths per minute (adults), controlled by neurons in medulla oblongata and pons, rate is determined by number of times respiratory muscles are stimulated
• Breath Sounds

  Abnormal breath sounds, called adventitious breath sounds, occur when air passes through narrowed airways or airways filled with fluid or mucus, or when pleural linings are inflamed, absence of breath sounds over some lung areas is also a significant finding
• Assessing the Thorax and Lungs requires the following equipment: Examination gown, Drape, Working Gloves, Stethoscope, Drop light (or any other light source), Face Mask, Skin Marker, Metric Ruler
• Collection of Subjective Data

  • Present Health History: Dyspnea, Chest Pain, Cough, Gastrointestinal Symptoms
  • Past Health History: History of Respiratory Disease, Thoracic Surgery / Trauma, Allergies, Medications, Previous Diagnostic/Lab Results
  • Family Health History: Lung disease, Smokers
  • Lifestyle: Diet, Smoke, Exposure to environmental hazards, Activity, exercise, rest and sleep pattern
• Gathered subjective data provides focus on your physical assessment, having a complete and accurate history taking enhances the collection of objective data.
• Abnormal Findings for Posterior Thorax

  • Pigeon Chest, Funnel Chest, Barrel Chest, exaggerated spinal curvatures (kyphosis, lordosis), spinal column deviates to one side, often accentuated when bending over, shoulders or hips not even
• Problems with the Spine include Spinal Deviation (Lordosis, Kyphosis and Scoliosis) and Slipped Disc (Herniated Disc)
• Spinal Deviation

  • Exaggerated spinal curvatures (kyphosis, lordosis)
  • Spinal column deviates to one side, often accentuated when bending over
  • Shoulders or hips not even
• Slipped Disc

  Herniated Disc - a vertebral disc that is displaced or partly protruding, pressing on nearby nerves and causing back pain or sciatica
• Posterior Thorax Examination

  1. Palpate posterior thorax

  2. Assess temperature and integrity of chest skin

  3. Palpate for bulges, tenderness, or abnormal movements
• Normal Posterior Thorax


  • Skin intact; uniform temperature
  • Chest wall intact; no tenderness; no masses
• Abnormal Posterior Thorax

  • Skin lesions; areas of hyperthermia
  • Lumps, bulges; depressions; areas of tenderness; movable structures (e.g., rib)
• Respiratory Excursion Examination

  1. Place palms over lower thorax (T9-T10)

  2. Ask client to take deep breath while observing movement
• Respiratory Excursion

  Movement of the thoracic diaphragm during breathing
• Tactile Fremitus Examination

  1. Place palmar surfaces on posterior thorax

  2. Ask client to repeat words

  3. Repeat down to lung base and compare
• Normal Tactile Fremitus

  • Bilateral symmetry
  • Fremitus felt most at lung apex
  • Low-pitched male voices more readily palpated
• Abnormal Tactile Fremitus

  • Decreased/absent fremitus (pneumothorax)
  • Increased fremitus (consolidated lung tissue, pneumonia)
• Percussion of Posterior Thorax

  1. Ask client to bend head and fold arms

  2. Percuss intercostal spaces systematically

  3. Compare sides
• Percussion


  Assessing lungs' resonance
• Normal Percussion

  • Resonance, except over scapula
  • Lowest resonance at diaphragm (8th-10th rib)
• Abnormal Percussion

  • Asymmetry in percussion notes
  • Areas of dullness/flatness (lung consolidation or mass)
• Auscultation of Posterior Thorax

  1. Place stethoscope at lung apex (C7)

  2. Ask client to breathe deeply

  3. Auscultate systematically, compare sides
• Auscultation

  Assessing airflow through airways
• Normal Breath Sounds

  • Vesicular, bronchial, bronchovesicular
• Abnormal Breath Sounds

  • Crackles/rales (fine or coarse)
  • Wheezing (sibilant or sonorous/rhonchi/gurgles)
  • Stridor
  • Pleural friction rub
• Inspection of Anterior Thorax

  Observe chest rise and fall, respiratory rate
• Respiratory Patterns


  Have localizing significance in altered consciousness
• Normal Breathing

  • 12-20 cpm, quiet, effortless