Chapter 27: Respiratory System Assessment

Critical physiological concepts include ventilation mechanisms driven by intrathoracic pressure changes, pulmonary compliance and resistance factors affecting breathing efficiency, and the role of surfactant in preventing alveolar collapse. The chapter emphasizes respiratory control mechanisms through chemoreceptors and mechanical receptors that respond to carbon dioxide, oxygen, pH levels, and airway irritants. Multiple defense mechanisms protect the respiratory system, including mucociliary clearance, cough reflexes, reflex bronchoconstriction, and alveolar macrophage activity. Age-related respiratory changes receive significant attention, highlighting decreased chest wall compliance, reduced elastic recoil, diminished alveolar function, weakened respiratory muscles, and impaired immune responses that increase infection and aspiration risks in older adults. The systematic assessment approach integrates comprehensive history-taking covering smoking exposure, occupational hazards, environmental risks, and functional health patterns with thorough physical examination techniques including inspection for chest symmetry and breathing patterns, palpation for tactile fremitus and chest expansion, percussion for tissue density changes, and auscultation for normal and adventitious breath sounds. Diagnostic procedures covered include arterial blood gas analysis, pulse oximetry, capnography, sputum studies, tuberculosis skin testing, bronchoscopy procedures, various lung biopsy techniques, thoracentesis, pulmonary function testing, and radiological imaging studies that provide comprehensive respiratory system evaluation data for clinical decision-making.