clinical examination of respiratory system

Inspection

A. Upper Respiratory Tract

1. Oral Cavity

• Oral hygiene
• Dental caries
• Oral thrush
• Tonsils

2. Nose

• Deviated nasal septum
• Nasal polyps may be seen in:
  • Wegener’s granulomatosis
  • Allergic asthma
  • Allergic bronchopulmonary aspergillosis (ABPA)
  • Cystic fibrosis

3. Pharynx

• Post-nasal drip
• Lymphoma deposits

B. Lower Respiratory Tract

1. Areas for Comparison (bilateral)

• Supraclavicular
• Infraclavicular
• Mammary
• Axillary
• Infra-axillary
• Suprascapular
• Interscapular
• Infrascapular

2. Position of Trachea

• Trail’s sign: undue prominence of clavicular head of sternomastoid on side of tracheal deviation (due to relaxation of pretracheal fascia).

3. Position of Apex Beat

• Shifts to the side of mediastinal shift.

4. Symmetry of Chest

• Normal: symmetrical, elliptical cross-section.
• AP : Transverse diameter → 5:7
• Subcostal angle → 90° (more acute in males).
• Look for:
  • Drooping shoulder
  • Hollowness/fullness (supraclavicular, infraclavicular)
  • Rib crowding
  • Kyphosis / Scoliosis

Scoliosis Differentiation

• Convexity + lung lesion same side → congenital
• Convexity opposite lung lesion → acquired

5. Skin Over Chest

• Engorged veins, nodules (sarcoid, malignancy)
• Intercostal scars (post-drainage of pleural effusion/empyema/pneumothorax)
• Discharging sinuses (TB)
• Intercostal swelling near sternum (empyema necessitans)

6. Chest Deformities

• Flat chest: AP:Transverse = 1:2 (TB, fibrothorax)
• Barrel chest: AP:Transverse = 1:1 (infancy, old age, COPD/emphysema)
• Pigeon chest (Pectus carinatum): sternum protrusion (Marfan’s, asthma, rickets)
• Pectus excavatum (funnel chest): sternum depression, apex beat displaced, restricted lung capacity (Marfan’s)
• Harrison’s sulcus: horizontal grooves from diaphragm pull (childhood asthma, rickets, adenoids)
• Rickety rosary: beading at costochondral junction (rickets)
• Scorbutic rosary: sharp rib angulation (vitamin C deficiency)

7. Spinal Deformities

• Kyphoscoliosis: apex beat shift, ↓ ventilatory capacity, ↑ work of breathing
• Ankylosing spondylitis: restricted chest expansion, ↓ lung capacity

8. Movement of Chest

• Normal RR: 14–18/min
• Breathing type:
  • Women → thoraco-abdominal
  • Men → abdomino-thoracic
• Pulse:Respiration ratio: 4:1
• Abnormal rates:
  • Tachypnoea (>20/min): exertion, fever, hypoxia, pneumonia, pulmonary oedema, PE, ARDS, acidosis
  • Bradypnoea (<12/min): alkalosis, hypothyroidism, narcotics, raised ICP
  • Hyperpnoea: acidosis, brainstem lesion, hysteria

9. Rhythm of Breathing

• Inspiration: active (external intercostals + diaphragm)
• Expiration: passive (elastic recoil)
• Accessory inspiratory muscles: scaleni, trapezius, pectorals
• Accessory expiratory muscles: abdominals, latissimus dorsi

10. Abnormal Breathing Patterns

• Regular:
  • Cheyne-Stokes: hyperpnoea + apnoea (CHF, renal failure, narcotics, ↑ ICP)
  • Kussmaul’s: ↑ rate + depth (metabolic acidosis, pontine lesion)
• Irregular:
  • Biot’s: apnoea between shallow/deep breaths (meningitis)
  • Ataxic: random deep + shallow (brainstem lesion)
  • Apneustic: inspiratory/expiratory pauses (pontine lesion)
  • Cogwheel: interrupted pattern (nervous state)
  • Pursed-lip: seen in COPD/emphysema (prevents alveolar collapse)

Palpation

1. Position of the Trachea

• Confirmed by slightly flexing the neck so that the chin remains in the midline.
• The index finger is inserted into the suprasternal notch, and the tracheal ring is palpated.
• Slight rightward deviation of the trachea is considered normal.

2. Tracheal Tug – Oliver’s Sign

• Method: Stand behind the patient → Raise the chin → Grasp cricoid cartilage during deglutition with both hands.
• Positive sign: Downward tug felt during cardiac systole.
• Seen in: Aortic arch aneurysm.
• False-positive: Mediastinal tumour attached to aortic arch.
• False-negative: Non-pulsatile (thrombosed) aortic aneurysm.

3. Inspiratory Tracheal Descent

• Seen in the suprasternal region during inspiration in COPD.

4. Confirmation of Apical Impulse

• Simultaneous shift of apical impulse and trachea, in the absence of chest wall deformity, suggests mediastinal shift.
• External masses (thyroid, thymus, lymph nodes) must be considered when assessing tracheal position.

5. Altered Position of Apical Impulse

• Scoliosis: Right-sided convexity pushes impulse further left.
• Pectus excavatum.
• Ventricular enlargement.

6. Tracheal Shift

• Pushed to opposite side in: Pleural effusion, Pneumothorax, Tumour.
• Pulled to same side in: Fibrosis, Lung collapse.
• Shifted to same side in pleural effusion in: Mesothelioma, Empyema/effusion with underlying fibrosis, Mass with collapse and effusion.

7. Measurement of Chest Expansion

• Done using an inch tape.
• In males: Measured at nipple level.
• In females: Measured below the breasts.
• Normal: 5–8 cm.
• Severe emphysema: Expansion < 1 cm.
• Non-respiratory restriction: Ankylosing spondylitis.

8. Assessment of Symmetry of Chest Expansion

• Upper thorax: Examiner behind, hands over supraclavicular fossae → Compare during quiet breathing.
• Mid and Lower thorax:
  • Anterior: Examiner faces patient → Fingertips symmetrically on rib cage → Thumbs approximate at midline → Thumb separation on deep inspiration = expansion.
  • Posterior: Same technique on back → Fold of skin held between thumbs disappears more on the side of better expansion.
• Minimal difference detection: Patient exhales fully (residual volume) → Inhales fully (TLC) → Compare hemithoraces.

9. Tenderness Over Chest Wall

• Empyema.
• Parietal pleura or soft tissue inflammation.
• Osteomyelitis.
• Tumour infiltration.
• Amoebic liver abscess (non-respiratory).

10. Detection of Subcutaneous Emphysema

• Spongy, crepitant feeling on palpation.
• Seen in: Chest wall/rib injury, Pneumothorax, Oesophageal rupture.

11. Tactile Fremitus

• Palpable added sounds: Rhonchi (better felt than crackles).
• Friction fremitus: Palpable pleural rub.
• Vocal fremitus: Vibration felt when patient repeats “ninety-nine” or “one-one-one”.
• Method: Use flat of hand or ulnar border → Compare identical areas on both sides.
• Interpretation:
  • Increased: Consolidation.
  • Decreased: Pleural effusion.

12. Special Clinical Features of Importance

• General restriction of expansion: COPD, Extensive bilateral lung disease, Ankylosing spondylitis, Interstitial lung disease, Systemic sclerosis (hide-bound chest).
• Asymmetrical expansion: Pleural effusion, Pneumothorax, Extensive consolidation, Lung collapse, Fibrosis.
• In all these, diminished expansion occurs on the affected side.

Percussion

1. General Principles

• Position of the patient: Sitting posture preferred; supine avoided (alters percussion note).
• Specific positions:
  • Anterior percussion: Patient erect, hands by side.
  • Posterior percussion: Head bent forward, arms crossed over shoulders (scapulae moved apart).
  • Lateral percussion: Hands placed over head.

2. Objectives of Percussion

• Assess degree of resonance over symmetrical chest areas.
• Map out abnormal percussion notes.

3. Cardinal Rules of Percussion

• Pleximeter: Middle finger of left hand firmly over intercostal space; other fingers off chest wall. Apply greater pressure in thick chest walls.
• Plexor: Middle/index finger of right hand strikes middle phalanx of pleximeter.
• Technique: Movement sudden from wrist; finger removed immediately to avoid damping.
• Order: Proceed from normal → abnormal areas.
• Alignment: Long axis of pleximeter parallel to organ border.

4. Areas of Percussion

• Anterior chest wall:
  • Clavicle: Direct percussion over medial 1/3rd.
  • Supraclavicular region (Kronig’s isthmus):
    • Band of resonance (5–7 cm).
    • Boundaries: Medial – scalenus; Lateral – acromion; Anterior – clavicle; Posterior – trapezius.
    • Findings: Hyper-resonance → emphysema; Impaired → pulmonary TB or apical malignancy.
  • Infraclavicular region: 2nd–6th intercostal spaces (cardiac dullness limits left comparison).
• Lateral chest wall: 4th–7th intercostal spaces.
• Posterior chest wall: Suprascapular (above scapular spine), Interscapular (between scapulae), Infrascapular (up to 11th rib).

5. Types of Percussion Notes and Associated Lesions

Percussion Note	Description	Associated Conditions
Tympanitic	Drum-like	Hollow viscus
Subtympanitic (skodiac/boxy)	Between tympanic & resonant	Above pleural effusion
Hyper-resonant	Increased air content	Pneumothorax
Resonant	Normal	Normal lung
Impaired	Reduced resonance	Pulmonary fibrosis, cavity with fibrosis
Dull	Thud-like	Consolidation, collapse, pleural thickening
Stony dull	Extremely flat	Pleural effusion, empyema, thickened pleura with pathology

6. Crack Pot Resonance

• Tympanitic note like striking moist clasped hands against knee.
• Seen in: Large pulmonary cavity communicating with bronchus.

7. Normal Percussion Note in Diseased Lungs

• May still be resonant in: Chronic bronchitis, Bronchial asthma, Interstitial lung disease, Diffuse emphysema.

8. Percussion on the Right Side

• Liver dullness: From 5th intercostal space down midclavicular line to costal margin.

9. Tidal Percussion

• Use: Differentiate hepatic dullness from pleural/parenchymal pathology.
• Technique:
  • Percuss 5th intercostal space (MCL) at rest → ask deep breath.
  • Resonant: Liver pushed down = normal.
  • Dullness persists: Parenchymal/pleural lesion (if no diaphragmatic paralysis).

10. Percussion on the Left Side – Traube’s Space

• Surface anatomy:
  • Vertical: 6th costochondral junction → 9th rib (mid-axillary line).
  • Connected above & below by left costal margin → semilunar space.
• Contents: Fundus of stomach → normally tympanitic.
• Boundaries: Right – liver; Left – spleen; Above – lung; Below – costal margin.
• Obliterated in: Left pleural effusion, massive splenomegaly, enlarged left liver lobe, full stomach, fundal tumour, massive pericardial effusion.
• Shifted upwards in: Left diaphragmatic paralysis, left lower lobe collapse, left lung fibrosis.

11. Special Clinical Features of Importance

• Percussion tenderness: Empyema, parietal pleura inflammation.
• Straight line dullness: Hydropneumothorax.
• Shifting dullness:
  • Detects mobile pleural fluid.
  • Hydropneumothorax: Dullness in axilla (sitting) → resonant lying on healthy side (immediate shift).
  • Pleural effusion: Shift occurs slowly.
• Ellis’ “S” shaped curve:
  • Seen in moderate pleural effusion → dullness highest in axilla, lowest paravertebral.
  • Theories: Capillary suction draws fluid upward; or radiological illusion.

Auscultation

1. General Principles of Auscultation

• Most normal lung sounds are low-pitched → bell is ideal, but diaphragm commonly used for efficiency.
• Patient should breathe through the mouth, not nose.
• Avoid auscultation within 2–3 cm of midline in upper chest (normal bronchial character may be heard).
• In hairy chest → moisten skin & press firmly to prevent artefactual rubbing sounds.

2. Auscultatory Areas

• Anterior: Above clavicle → 6th rib.
• Axilla: Up to 8th rib.
• Posterior: Above scapular spine → 11th rib.

3. Technique of Auscultation

• Identify & map abnormal sounds → track extent and transition zones.
• If pleural pain → avoid deep breathing, prefer testing vocal resonance.
• After coughing:
  • Pleural rub: unchanged.
  • Rhonchi/crackles: may change.

4. Importance of Auscultation

• Assess:
  • Character & intensity of breath sounds.
  • Presence of added sounds.
  • Vocal resonance (voice & whisper).
  • Miscellaneous abnormal sounds.

5. Breath Sounds

5.1 Vesicular Breath Sound

• Low-pitched, rustling; produced by filtering effect of parenchyma.
• Inspiratory > Expiratory (3:1).
• No pause between phases.
• Diminished in: Asthma (silent chest), Tumour, Small effusion, Pleural thickening, Collapse with occluded bronchus, Emphysema.

5.2 Bronchial Breath Sound

• Loud, high-pitched, guttural.
• Inspiration shorter, expiration prolonged/equal.
• Distinct pause between inspiration & expiration.
• Heard over airless/consolidated lung.
• Types:
  • Tubular: High-pitched. Seen in pneumonic consolidation, collapse (patent bronchus), above pleural effusion.
  • Cavernous: Low-pitched. Thick-walled cavity with bronchial communication.
  • Amphoric: Low-pitched, metallic tone. Large smooth-walled cavity, bronchopleural fistula, tension pneumothorax.

5.3 Bronchovesicular Breath Sound

• Intermediate between vesicular & bronchial.
• Louder, longer, hollow, higher pitch.
• Normal sites: Upper sternum, between scapulae (T3–T4), apices.
• Pathological: Consolidation (induction/resolution phases).

5.4 Absent Breath Sounds

• Massive pleural effusion.
• Fibrothorax.
• Collapse with occluded bronchus.
• Pneumothorax.
• Silent chest (near-fatal asthma).
• Pneumonectomy.
• Lung agenesis.

6. Added Sounds

6.1 Crackles (Rales)

• Non-musical, interrupted, explosive; short duration.
• Types: Fine (alveolar), Coarse (bronchial/bronchiolar).
• Timing:
  • Early inspiratory → Chronic bronchitis.
  • Mid-inspiratory → Bronchiectasis.
  • Late inspiratory → Asbestosis, fibrosis, pneumonitis, ILD, pulmonary edema.
  • Expiratory → Chronic bronchitis, pulmonary edema.
• Mechanisms: Air bubbling through secretions; sudden opening of closed alveoli/bronchioles.
• Clinical insights:
  • Without sputum → ILD.
  • With sputum → Parenchymal disease.
  • Fine localized (apices) → Early TB.
  • Fine basal → Early LVF.
  • Coarse (“death rattle”) → End-stage pulmonary edema.

6.2 Rhonchi (Wheezes)

• Musical, continuous sounds.
• Types:
  • Low-pitched (sonorous) → Large airways.
  • High-pitched (sibilant) → Small airways.
• Variants:
  • Fixed monophonic: Constant pitch/location → fixed obstruction (tumour, foreign body, stenosis, granuloma).
  • Random monophonic: Variable → asthma.
  • Expiratory polyphonic: Multiple notes, start & end together → emphysema (central airway compression).
  • Sequential inspiratory: Delayed opening of distal airways → pulmonary fibrosis, fibrosing alveolitis, asbestosis.

7. Voice Sounds (Vocal Resonance)

• General: Heard via stethoscope; may be ↑, ↓, or qualitatively altered.
• Types:
  • Bronchophony: Voice close & indistinct → consolidation, cavity, above effusion (normal near trachea).
  • Aegophony: Nasal, bleating “E → A” → consolidation, above effusion, cavity (present in alveolar fluid, absent in fibrosis).
  • Whispering pectoriloquy: Whispered syllables audible → consolidation.

8. Miscellaneous Sounds

• Pleural rub: Superficial, squeaking/grating; best with firm pressure; not altered by cough; associated with pain.
• Pleuropericardial rub: In pleurisy adjacent to pericardium → caused by pleural layers moving over one another during cardiac pulsation.