Respiratory System Anatomy

Lung Structure

• The lungs are paired but not precisely symmetrical.
• The left lung has two lobes: upper and lower, which separate at the 6th rib.
• The left lung is smaller due to the space occupied by the heart.
• The right lung has three lobes: upper, middle, and lower, with the middle lobe extending from the 4th to 6th rib.
• The apex of the lung is approximately 3 cm above the clavicle, pointing towards the substernal notch.
• The base of the lungs lies at around T10.

Palpation Techniques

• To confirm symmetrical chest expansion, stand behind the patient and place warmed hands at T10/Tenth rib.
• Point thumbs towards the spine and fingers laterally, with palms lightly contacting the posterolateral surfaces.
• Pinch a small fold of skin between the thumbs, keeping them about 5cm apart.
• Ask the patient to exhale and then inhale, noting the movement between the thumbs.
• Symmetrical movement indicates normal expansion, while unequal expansion may indicate pneumothorax, rib fractures, pneumonia, or trauma.
• For anterolateral assessment, place hands along the coastal margins with thumbs pointing towards the xiphoid process.
• Thumbs should move apart symmetrically by 3-5 cm when the patient inhales deeply.

Lung Structure

• The lungs are paired but not precisely symmetrical.
• The left lung has two lobes: upper and lower, which separate at the 6th rib.
• The left lung is smaller due to the space occupied by the heart.
• The right lung has three lobes: upper, middle, and lower, with the middle lobe extending from the 4th to 6th rib.
• The apex of the lung is approximately 3 cm above the clavicle, pointing towards the substernal notch.
• The base of the lungs lies at around T10.

Palpation Techniques

• To confirm symmetrical chest expansion, stand behind the patient and place warmed hands at T10/Tenth rib.
• Point thumbs towards the spine and fingers laterally, with palms lightly contacting the posterolateral surfaces.
• Pinch a small fold of skin between the thumbs, keeping them about 5cm apart.
• Ask the patient to exhale and then inhale, noting the movement between the thumbs.
• Symmetrical movement indicates normal expansion, while unequal expansion may indicate pneumothorax, rib fractures, pneumonia, or trauma.
• For anterolateral assessment, place hands along the coastal margins with thumbs pointing towards the xiphoid process.
• Thumbs should move apart symmetrically by 3-5 cm when the patient inhales deeply.

Tactile Fremitus

• Palpation vibration felt using the palmar aspect of the hand
• Most prominent between the scapulae and around the sternum, where major bronchi are closest to the chest wall
• Decreases as you progress down the chest
• Decreased fremitus occurs when anything obstructs transmission of vibrations, such as:
  • Effusions
  • Pneumothorax
  • Emphysema
• Increased fremitus occurs with compression or consolidation of lung tissue, such as:
  • Pneumonia
• Note the correct placement of hands for palpating for a vibration
• Use the patient's vocalization of "99" or "blue moon" to detect changes in the intensity of the vibration

Breath Sounds (Normal)

• Bronchial Sounds
  • High-pitched and loud
  • Heard on inspiration and expiration over the trachea and larynx
  • Best heard over the trachea
• Bronchovesicular Sounds
  • Medium-pitched and blowing sounds of medium intensity
  • Heard on inspiration and expiration over the major bronchi
  • Located at the upper sternum anteriorly and posteriorly between the scapulae (especially on the right side)
• Vesicular Sounds
  • Low-pitched and soft
  • Heard on inspiration and expiration
  • Sounds like wind rustling in the trees
  • Best heard over peripheral lung fields (except over scapula)
  • Located where air flows through smaller alveoli and bronchioles

Tactile Fremitus

• Palpation vibration felt using the palmar aspect of the hand
• Most prominent between the scapulae and around the sternum, where major bronchi are closest to the chest wall
• Decreases as you progress down the chest
• Decreased fremitus occurs when anything obstructs transmission of vibrations, such as:
  • Effusions
  • Pneumothorax
  • Emphysema
• Increased fremitus occurs with compression or consolidation of lung tissue, such as:
  • Pneumonia
• Note the correct placement of hands for palpating for a vibration
• Use the patient's vocalization of "99" or "blue moon" to detect changes in the intensity of the vibration

Breath Sounds (Normal)

• Bronchial Sounds
  • High-pitched and loud
  • Heard on inspiration and expiration over the trachea and larynx
  • Best heard over the trachea
• Bronchovesicular Sounds
  • Medium-pitched and blowing sounds of medium intensity
  • Heard on inspiration and expiration over the major bronchi
  • Located at the upper sternum anteriorly and posteriorly between the scapulae (especially on the right side)
• Vesicular Sounds
  • Low-pitched and soft
  • Heard on inspiration and expiration
  • Sounds like wind rustling in the trees
  • Best heard over peripheral lung fields (except over scapula)
  • Located where air flows through smaller alveoli and bronchioles

Tactile Fremitus

• Palpation vibration felt using the palmar aspect of the hand
• Most prominent between the scapulae and around the sternum, where major bronchi are closest to the chest wall
• Decreases as you progress down the chest
• Decreased fremitus occurs when anything obstructs transmission of vibrations, such as:
  • Effusions
  • Pneumothorax
  • Emphysema
• Increased fremitus occurs with compression or consolidation of lung tissue, such as:
  • Pneumonia
• Note the correct placement of hands for palpating for a vibration
• Use the patient's vocalization of "99" or "blue moon" to detect changes in the intensity of the vibration

Breath Sounds (Normal)

• Bronchial Sounds
  • High-pitched and loud
  • Heard on inspiration and expiration over the trachea and larynx
  • Best heard over the trachea
• Bronchovesicular Sounds
  • Medium-pitched and blowing sounds of medium intensity
  • Heard on inspiration and expiration over the major bronchi
  • Located at the upper sternum anteriorly and posteriorly between the scapulae (especially on the right side)
• Vesicular Sounds
  • Low-pitched and soft
  • Heard on inspiration and expiration
  • Sounds like wind rustling in the trees
  • Best heard over peripheral lung fields (except over scapula)
  • Located where air flows through smaller alveoli and bronchioles

Anterior Lung Landmarks

• Apex of the lungs begins 3-4 cm above the clavicle, marking the highest point
• Base of the lungs sits at the diaphragm, approximately at the 7th rib, marking the lowest point

Posterior Lung Landmarks

• Apex of the lungs is marked by the 7th cervical vertebra (C7), also known as the "big bump" at the top of the spine
• Base of the lungs sits at approximately the 10th thoracic spine (T10), extending to approximately T12 during inspiration
• Posterior lungs are primarily comprised of lower lobes
• Upper lobes are accessible from the apex at C7 to T3, where the oblique fissures begin

Anterior Lung Landmarks

• Apex of the lungs begins 3-4 cm above the clavicle, marking the highest point
• Base of the lungs sits at the diaphragm, approximately at the 7th rib, marking the lowest point

Posterior Lung Landmarks

• Apex of the lungs is marked by the 7th cervical vertebra (C7), also known as the "big bump" at the top of the spine
• Base of the lungs sits at approximately the 10th thoracic spine (T10), extending to approximately T12 during inspiration
• Posterior lungs are primarily comprised of lower lobes
• Upper lobes are accessible from the apex at C7 to T3, where the oblique fissures begin

Anterior Lung Landmarks

• Apex of the lungs begins 3-4 cm above the clavicle, marking the highest point
• Base of the lungs sits at the diaphragm, approximately at the 7th rib, marking the lowest point

Posterior Lung Landmarks

• Apex of the lungs is marked by the 7th cervical vertebra (C7), also known as the "big bump" at the top of the spine
• Base of the lungs sits at approximately the 10th thoracic spine (T10), extending to approximately T12 during inspiration
• Posterior lungs are primarily comprised of lower lobes
• Upper lobes are accessible from the apex at C7 to T3, where the oblique fissures begin

Breath Sounds

• Air passing through the tracheobronchial tree creates a characteristic set of audible sounds
• There are three types of breath sounds: bronchial, bronchovesicular, and vesicular

Changes in Breath Sounds

• Decreased or absent breath sounds occur when obstructed by secretions or loss of lung elasticity
• Increased (louder) breath sounds occur with consolidation or fluid (pneumonia), enhancing the bronchial sound as it moves through the lung fields

Crepitus

• A coarse crackling sensation palpable over the chest
• Caused by subcutaneous emphysema (air escapes the lungs and enters subcutaneous tissue)

Breath Sounds

• Air passing through the tracheobronchial tree creates a characteristic set of audible sounds
• There are three types of breath sounds: bronchial, bronchovesicular, and vesicular

Changes in Breath Sounds

• Decreased or absent breath sounds occur when obstructed by secretions or loss of lung elasticity
• Increased (louder) breath sounds occur with consolidation or fluid (pneumonia), enhancing the bronchial sound as it moves through the lung fields

Crepitus

• A coarse crackling sensation palpable over the chest
• Caused by subcutaneous emphysema (air escapes the lungs and enters subcutaneous tissue)

Breath Sounds

• Air passing through the tracheobronchial tree creates a characteristic set of audible sounds
• There are three types of breath sounds: bronchial, bronchovesicular, and vesicular

Changes in Breath Sounds

• Decreased or absent breath sounds occur when obstructed by secretions or loss of lung elasticity
• Increased (louder) breath sounds occur with consolidation or fluid (pneumonia), enhancing the bronchial sound as it moves through the lung fields

Crepitus

• A coarse crackling sensation palpable over the chest
• Caused by subcutaneous emphysema (air escapes the lungs and enters subcutaneous tissue)

High-Flow Delivery Devices

• Venturi Mask provides specific O2 concentrations (24-50%) with humidity, but has a low constant O2 flow, and may irritate skin, interfere with eating, drinking, and talking.
• High Flow Nasal Cannula offers adjustable FiO2 (21%-100%) with modifiable flow up to 60 LPM, and is suitable for adults, children, and infants, but FiO2 is dependent on patient respiratory pattern and input flow, and carries a risk of infection.

Low-Flow Delivery Devices

• Low Flow Nasal Cannula provides O2 concentrations of 24-28% at 1-2L/min, 32-36% at 3-4L/min, and 40-44% at 5-6L/min, and is safe, simple, and easily tolerated, but is not suitable for patients with nasal obstruction, and may cause drying of mucous membranes, dislodge easily, and skin irritation.
• Simple Face Mask provides O2 concentrations of 40-60% at 5-10L/min, and is useful for short periods of time, but is contraindicated for patients who retain CO2, and carries an increased risk of aspiration.
• Partial Rebreather and Partial Non-Rebreather devices provide O2 concentrations of 60-80% at 10-15L/min, and are useful for short periods of acute hypoxia, but may cause skin irritation, and the bag may twist/deflate.
• Full Non-Rebreather device provides O2 concentrations of up to 100% at 10-15L/min, and is useful for short periods of acute hypoxia, but may cause skin irritation, and the bag may twist/deflate.

High-Flow Delivery Devices

• Venturi Mask provides specific O2 concentrations (24-50%) with humidity, but has a low constant O2 flow, and may irritate skin, interfere with eating, drinking, and talking.
• High Flow Nasal Cannula offers adjustable FiO2 (21%-100%) with modifiable flow up to 60 LPM, and is suitable for adults, children, and infants, but FiO2 is dependent on patient respiratory pattern and input flow, and carries a risk of infection.

Low-Flow Delivery Devices

• Low Flow Nasal Cannula provides O2 concentrations of 24-28% at 1-2L/min, 32-36% at 3-4L/min, and 40-44% at 5-6L/min, and is safe, simple, and easily tolerated, but is not suitable for patients with nasal obstruction, and may cause drying of mucous membranes, dislodge easily, and skin irritation.
• Simple Face Mask provides O2 concentrations of 40-60% at 5-10L/min, and is useful for short periods of time, but is contraindicated for patients who retain CO2, and carries an increased risk of aspiration.
• Partial Rebreather and Partial Non-Rebreather devices provide O2 concentrations of 60-80% at 10-15L/min, and are useful for short periods of acute hypoxia, but may cause skin irritation, and the bag may twist/deflate.
• Full Non-Rebreather device provides O2 concentrations of up to 100% at 10-15L/min, and is useful for short periods of acute hypoxia, but may cause skin irritation, and the bag may twist/deflate.

Oxygen Devices

• Both high flow and low flow devices can deliver a range of inspired oxygen concentrations (FiO2) to patients.

High Flow Devices

• Control FiO2 with less dependence on patient's breathing pattern.
• Include device types:
  • Venturi masks
  • Large volume nebulizer
  • Blender masks
  • High flow nasal cannula

Low Flow Devices

• Include device types:
  • Low flow nasal cannula
  • Oxygen conserving nasal cannula
  • Simple face masks
  • Partial rebreather masks
  • Nonrebreather masks

Oxygen Devices

• Both high flow and low flow devices can deliver a range of inspired oxygen concentrations (FiO2) to patients.

High Flow Devices

• Control FiO2 with less dependence on patient's breathing pattern.
• Include device types:
  • Venturi masks
  • Large volume nebulizer
  • Blender masks
  • High flow nasal cannula

Low Flow Devices

• Include device types:
  • Low flow nasal cannula
  • Oxygen conserving nasal cannula
  • Simple face masks
  • Partial rebreather masks
  • Nonrebreather masks