Key Techniques for Effective Respiratory Examination: A Medical Student’s Guide

Introduction

Respiratory examination is a fundamental skill that all medical students and healthcare professionals must master. It's a crucial component of the physical examination, providing essential information about the respiratory system's function and potential pathologies. This guide aims to provide a step-by-step approach to performing a respiratory examination, focusing on both technique and clinical relevance.

Preparation and Setting

Before beginning the examination, ensure that the environment is suitable. The room should be well-lit and quiet, with the patient comfortably positioned. Ideally, the patient should be sitting up on an examination table, with the upper body exposed to the waist. It's essential to maintain patient dignity, so always provide a gown or drape to cover the lower body.

Hand Hygiene: As with any patient interaction, start with proper hand hygiene. This reduces the risk of infection and sets a professional tone for the examination.

Patient History: While this guide focuses on the physical examination, it is critical to remember that a thorough history-taking precedes any physical exam. Questions about respiratory symptoms (such as cough, sputum production, hemoptysis, dyspnea, wheezing, and chest pain) will guide your examination and help narrow down differential diagnoses.

Inspection

The first step in the respiratory examination is inspection. This is often overlooked but can provide valuable information before even laying a hand on the patient.

1. General Appearance:
   • Look for signs of respiratory distress: This includes the use of accessory muscles, nasal flaring, intercostal or supraclavicular retractions, and a distressed facial expression.
   • Observe the patient’s posture: Patients with respiratory difficulties often adopt positions that ease breathing, such as leaning forward with arms supported (tripod position).
2. Skin and Nails:
   • Cyanosis: A bluish discoloration of the lips, tongue, or extremities indicates hypoxemia.
   • Clubbing: Observe the nails for clubbing, which can suggest chronic hypoxia, lung cancer, or other significant pulmonary conditions.
3. Chest Wall:
   • Shape and Symmetry: Inspect the chest for deformities such as barrel chest, pectus excavatum, or pectus carinatum. Note any asymmetry, which could suggest underlying pathology like a large pleural effusion or pneumothorax.
   • Respiratory Rate and Rhythm: Count the respiratory rate and observe the rhythm. A normal adult respiratory rate is 12-20 breaths per minute. Note any tachypnea, bradypnea, or irregular breathing patterns such as Cheyne-Stokes respiration.
4. Scars and Skin Changes:
   • Look for surgical scars that may indicate previous thoracic surgery, skin changes like erythema or rashes, or signs of chronic conditions such as hyperpigmentation in areas of repeated irritation.

Palpation

Palpation helps assess the underlying structures and identify areas of tenderness or abnormal movement.

1. Chest Expansion:
   • Place your hands on the patient’s back: Thumbs should be positioned at the level of the 10th rib, with fingers spread out on the lateral aspects of the chest.
   • Ask the patient to take a deep breath: Observe the movement of your thumbs. They should move symmetrically apart as the chest expands. Asymmetry could indicate pathology such as lobar pneumonia, pleural effusion, or pneumothorax.
2. Tactile Fremitus:
   • Palpate the chest wall: Use the ulnar edge of your hand or fingers to assess tactile fremitus, which is the vibration felt on the chest wall when the patient speaks.
   • Ask the patient to say "ninety-nine" repeatedly: Fremitus is typically more pronounced in areas where the lung is closer to the chest wall and may be decreased or absent in areas of pleural effusion, pneumothorax, or obstructed bronchus. Increased fremitus may be found in areas of lung consolidation as seen in pneumonia.
3. Tenderness:
   • Palpate the ribs and intercostal spaces: Gently press along the ribs and intercostal spaces to identify any areas of tenderness, which may suggest rib fractures, pleuritis, or costochondritis.
4. Tracheal Position:
   • Check the tracheal position: The trachea should be midline. Deviation of the trachea could indicate significant pathology, such as a tension pneumothorax (away from the lesion) or large pleural effusion.

Percussion

Percussion is a technique used to assess the underlying structures by tapping on the chest wall and interpreting the sounds produced.

1. Technique:
   • Use your non-dominant hand's middle finger: Place it firmly against the chest wall in an intercostal space.
   • Strike the middle phalanx with the tip of your dominant hand's middle finger: The motion should come from the wrist, not the elbow.
2. Interpreting Percussion Notes:
   • Resonant: This is the normal sound heard over healthy lung tissue.
   • Hyperresonant: This may indicate air trapping, as seen in conditions like emphysema or a pneumothorax.
   • Dull: This sound is associated with consolidation (as in pneumonia), pleural effusion, or mass lesions.
   • Tympanic: Typically heard over areas of large air pockets, such as in a large pneumothorax.
3. Percussion of the Anterior, Lateral, and Posterior Chest:
   • Percuss systematically: Start from the apices down to the bases of the lungs, comparing the left and right sides at each level.

Auscultation

Auscultation is one of the most critical components of the respiratory examination, providing direct information about airflow through the respiratory tract.

1. Technique:
   • Use a stethoscope: Ensure the diaphragm of the stethoscope is in contact with the skin. Ask the patient to breathe deeply through the mouth.
   • Listen in a systematic manner: Start at the apices of the lungs and move symmetrically down the chest, comparing left to right. Don't forget to auscultate the lateral and posterior chest as well.
2. Breath Sounds:
   • Vesicular: The normal breath sound heard over most of the lung fields. It is soft and low-pitched.
   • Bronchial: Heard over the trachea and larger airways, these sounds are louder and higher-pitched. If heard over lung fields, they may indicate consolidation.
   • Bronchovesicular: Intermediate sounds heard over the central airways.
   • Adventitious Sounds: These include crackles (rales), wheezes, and pleural rubs.
     • Crackles: Fine or coarse sounds that may indicate conditions such as pulmonary edema, fibrosis, or pneumonia.
     • Wheezes: High-pitched sounds that suggest narrowed airways, as in asthma or chronic obstructive pulmonary disease (COPD).
     • Pleural Rub: A rough, grating sound that may indicate pleuritis.
3. Special Techniques:
   • Egophony: Ask the patient to say "E" while auscultating. If it sounds like "A," this suggests consolidation.
   • Whispered Pectoriloquy: Ask the patient to whisper "ninety-nine." In areas of consolidation, the whisper will be heard more clearly.
   • Bronchophony: Ask the patient to say "ninety-nine." Over normal lung tissue, the sound should be muffled. If it is loud and clear, this suggests consolidation.

Interpretation and Clinical Correlation

After completing the respiratory examination, it’s essential to correlate the findings with the patient’s history and other clinical data.

1. Differential Diagnoses Based on Examination Findings:
   • Normal Findings: Likely indicate healthy lungs.
   • Diminished Breath Sounds with Hyperresonance: May suggest pneumothorax or emphysema.
   • Dullness to Percussion with Decreased Fremitus: Could indicate pleural effusion.
   • Increased Fremitus with Dullness: Suggests consolidation, such as in pneumonia.
   • Wheezes: Commonly seen in asthma or COPD exacerbation.
   • Crackles: Fine crackles may suggest pulmonary fibrosis, while coarse crackles are often associated with heart failure or pneumonia.
2. Documenting the Examination:
   • Be concise yet thorough. Use medical terminology to describe findings and always compare bilaterally.
3. Communicating Findings:
   • Explain the findings to the patient in understandable terms, especially if the examination reveals abnormalities that may require further investigation or treatment.

Conclusion

Mastering the respiratory examination is crucial for all healthcare professionals. It is a skill that combines observation, technique, and clinical judgment. By following this guide, you can ensure a comprehensive and systematic approach to examining the respiratory system, leading to better patient care and more accurate diagnoses.