Medical sem book 200-300

Persistent Localized Wheeze

  • Definition: A type of wheeze characterized by a partial obstruction of a bronchus due to causes such as tumors or foreign bodies.

  • Loudness: It can be persistent and localized, often diagnosed through auscultation.

Entirely or Predominantly Inspiratory Wheeze

  • Stridor: Often louder in the neck than over the chest, indicating a partial obstruction of the larynx or trachea.

  • Significance: Stridor necessitates immediate medical attention due to critical airway obstruction.

Rhonchi

  • Sound Characteristics: Relatively low-pitched sounds (around 200 Hz) resembling snoring, produced by transient mucus plugging.

  • Indications: They indicate secretions in large airways and are often associated with conditions such as bronchitis.

  • Clearing of Sounds: The resolution of crackles or wheezes after coughing suggests their causation by secretions (e.g., in bronchitis or atelectasis).

Pleural Rub

  • Description: A creaking sound similar to new leather or footsteps in fresh snow, caused by inflamed pleural surfaces rubbing against each other.

  • Auscultation Phases: Typically heard during both inspiration and expiration, particularly at the end of inspiration/start of expiration.

  • Disappearance: The rub may disappear if inflamed pleural surfaces are separated by fluid.

Transmitted Voice Sounds

  • Purpose: Listening to the transmitted sounds of the patient's voice via auscultation can help identify abnormalities.

  • Techniques:

    1. Bronchophony: Ask the patient to say "ninety-nine"; normally muffled sounds suggest air-filled lungs.

    2. Egophony: Ask the patient to say "E"; a change to an "A" sound indicates consolidation (e.g., lobar pneumonia).

    3. Whispered Pectoriloquy: Whispered sounds normally heard faintly; clearer sounds suggest lung consolidation.

Correlating Examination Findings

  • Consolidation Signs:

    • Dullness on percussion

    • Crackles

    • Increased breath sounds

    • Increased tactile fremitus

  • Pleural Effusion Signs:

    • Dullness

    • Decreased breath sounds

    • Decreased tactile fremitus

  • Obstructive Lung Disease Signs:

    • Barrel chest

    • Diminished chest expansion

    • Accessory muscle use

    • Cyanosis

    • Diminished diaphragmatic excursion

    • Impaired breath sounds

Documenting Respiratory Findings

  1. Normal Findings:

    • Trachea is midline, chest appears normal, palpation normal, and breath sounds clear upon auscultation.

  2. Abnormal Findings (example):

    • Midline trachea with increased tactile fremitus and dull percussion note on one side; bronchial breath sounds and crackles noted.

  3. Tracheal Deviation Example:

    • Abnormal deviation with decreased tactile fremitus and dull percussion in one area; absence of breath sounds noted.

Imaging of Respiratory Diseases

  • X-ray Types:

    • Plain chest X-ray (CXR)

    • CT scan

    • Ultrasound

    • Scintigraphic imaging

    • PET scan

    • MRI

    • CT pulmonary angiography

Chest X-ray Basics

  • Views: Standard PA and lateral views provide crucial information on lung fields, heart, mediastinum, and vascular structures.

  • Identification: Key structures in CXR analysis include trachea positioning, mediastinal width, heart evaluation, and diaphragm position.

X-ray Abnormalities Identification**

  • Nodular Shadows: Suggestive of neoplasms, infections, or granulomas.

  • Consolidation: Alveolar filling with dense materials (pus, blood, cells) resulting in lobar or segmental opacities.

  • Pleural Effusion: Blunting of the costophrenic angle appears with varying liquid quantities.

CT Imaging**

  • Purpose: Enhances anatomical visualization, particularly mediastinal structures and detects pulmonary lesions.

  • Contrast Use: Often involves intravenous contrast for better quality images.

Diagnostic Procedures in Respiratory Illnesses**

  • Endoscopic Exam Types:

    • Bronchoscopy for tracheal and bronchial inspection.

    • Mediastinoscopy for tissue sampling in the mediastinal compartment.

Pulmonary Function Tests (PFTs)**

  • Measured Components: FEV1, FVC, PEFR, and spirometry graphs help analyze lung function and airflow limitations.

  • Abnormal Patterns: Obstructive, restrictive, or mixed ventilatory patterns may emerge based on spirometric data.

Arterial Blood Gas Analysis**

  • Key Measurements: PaO2, PaCO2, HCO3 levels, aiding in assessing respiratory function and acid-base balance.

Additional Studies for Assessment**

  • Sputum Examination & Culture: For microbiological and cytological analysis.

  • Haematological Tests: Checking hemoglobin, D-dimer for clot presence, and routine chemistry.

Diagnostic Aspiration**

  • Clear small or loculated effusions with ultrasound guidance for optimal drainage and analysis.

Skin-Prick Tests**

  • Use: Assess for allergic sensitivities that may impact respiratory health.