Assessment of Respiratory Function

Chapter 20 Assessment of Respiratory Function Purpose of the Respiratory System ❖ Deliver oxygen to and expel carbon dioxide from the body, works in conjunction with the circulatory system ❖ Upper respiratory system warms and filters air ❖ Lower respiratory system accomplishes gas exchan...

Chapter 20 Assessment of Respiratory Function Purpose of the Respiratory System ❖ Deliver oxygen to and expel carbon dioxide from the body, works in conjunction with the circulatory system ❖ Upper respiratory system warms and filters air ❖ Lower respiratory system accomplishes gas exchange Copyright © 2018 Wolters Kluwer · All Rights Reserved Structures of the Upper Respiratory Tract ❖ Nose ❖ Sinuses and nasal passages ❖ Pharynx ❖ Tonsils and adenoids ❖ Larynx: epiglottis, glottis, vocal cords, and cartilages ❖ Trachea Copyright © 2018 Wolters Kluwer · All Rights Reserved Upper Respiratory System Copyright © 2018 Wolters Kluwer · All Rights Reserved Question #1 Is the following statement true or false? The purpose of the cilia is to move the mucus back to the larynx Copyright © 2018 Wolters Kluwer · All Rights Reserved Answer to Question #1 True The purpose of the cilia is to move the mucus back to the larynx Copyright © 2018 Wolters Kluwer · All Rights Reserved Cross-section of Nasal Cavity Copyright © 2018 Wolters Kluwer · All Rights Reserved Paranasal Sinuses Copyright © 2018 Wolters Kluwer · All Rights Reserved  Lower Respiratory System Structures ❖ Two lungs: five lobes o Left: upper and lower o Right: upper, middle, and lower ❖ Pleura ❖ Mediastinum ❖ Bronchi and bronchioles ❖ Alveoli Copyright © 2018 Wolters Kluwer · All Rights Reserved Lower Respiratory System Copyright © 2018 Wolters Kluwer · All Rights Reserved Alveoli Copyright © 2018 Wolters Kluwer · All Rights Reserved The Lobes of the Lungs and Bronchiole Tree Copyright © 2018 Wolters Kluwer · All Rights Reserved Perfusion: Oxygen Transport Copyright © 2018 Wolters Kluwer · All Rights Reserved Perfusion: Carbon Dioxide Transport Copyright © 2018 Wolters Kluwer · All Rights Reserved Respiration ❖ Process of gas exchange between the atmospheric air and the blood and between the blood and cells of the body ❖ Oxygen concentration in capillaries of the lungs is lower than in the alveoli ❖ Due to this concentration gradient: oxygen diffuses from the alveoli to the blood ❖ Movement of air in and out of the airways continually replenishes the oxygen and removes the carbon dioxide from the airways and lungs Copyright © 2018 Wolters Kluwer · All Rights Reserved Ventilation: Breathing (Air Exchange) Copyright © 2018 Wolters Kluwer · All Rights Reserved Ventilation ❖ Expiration: relaxation of the diaphragm (movement of chamber floor upward) relaxation of external intercostal muscles, increasing intrathoracic pressure (positive pressure), air exits the airways, deflation and elastic recoil of the lungs ❖ 1 respiration = inspiration, 1/3 of the respiratory cycle; and expiration, 2/3 of the respiratory cycle Copyright © 2018 Wolters Kluwer · All Rights Reserved Biot’s Copyright © 2018 Wolters Kluwer · All Rights Reserved Cheyne-Stokes Copyright © 2018 Wolters Kluwer · All Rights Reserved Kussmaul’s Copyright © 2018 Wolters Kluwer · All Rights Reserved Gas Exchange and Respiratory Function Copyright © 2018 Wolters Kluwer · All Rights Reserved Ventilation–Perfusion (V/Q Ratio) ❖ Adequate gas exchange depends upon balanced V/Q ratio ❖ Imbalanced V/Q ratio causes shunting of blood and results in hypoxia ❖ Supplemental oxygen may eliminate hypoxia ❖ V/Q ratio imbalances, refer to Chart 20-2 Copyright © 2018 Wolters Kluwer · All Rights Reserved  Question #2 What is gas exchange between the lungs and blood and between the blood and tissues? A. Diffusion B. Perfusion C. Respiration D. Ventilation Copyright © 2018 Wolters Kluwer · All Rights Reserved  Answer to Question #1 C. Respiration Respiration is gas exchange between the lungs and blood and blood and tissues Diffusion is exchange of oxygen and carbon dioxide at the alveolar–capillary membrane Perfusion is arterial/venous circulation filling pulmonary capillaries with blood Ventilation is flow of air in and out of the lungs Copyright © 2018 Wolters Kluwer · All Rights Reserved Assessment ❖ Normal breath sounds: o Vesicular o Bronchovesicular o Bronchial ❖ Abnormal (adventitious) breath sounds: o Crackles o Stridor o Wheezes o Friction rub o Refer to Table 20-7 Copyright © 2018 Wolters Kluwer · All Rights Reserved Question #3 Is the following statement true or false? Wheezes are considered an adventitious breath sound Copyright © 2018 Wolters Kluwer · All Rights Reserved Answer to Question #2 True Wheezes are considered an adventitious breath sound Copyright © 2018 Wolters Kluwer · All Rights Reserved Lung Capacity ❖ Tidal volume (TV) ❖ Inspiratory reserve(IRV) ❖ Expiratory reserve(ERV) ❖ Vital capacity (VC) VC = TV + IRV + ERV ❖ Forced expiratory volume (FEV) ❖ Refer to Table 20-1 Copyright © 2018 Wolters Kluwer · All Rights Reserved Inspiratory Force ❖ Evaluates the inspiratory effort in one breath ❖ Monometer: device to measure inspiratory effort can be attached to a mask or endotracheal tube ❖ Normal inspiratory pressure is approximately 100 cm H2O ❖ Force of less than 25 cm usually requires mechanical ventilation Copyright © 2018 Wolters Kluwer · All Rights Reserved Arterial Blood Gases ❖ Measurement of arterial oxygenation and carbon dioxide levels ❖ Used to assess the adequacy of alveolar ventilation and the ability of the lungs to provide oxygen and remove carbon dioxide ❖ Also assesses acid–base balance Copyright © 2018 Wolters Kluwer · All Rights Reserved Pulse Oximetry ❖ A noninvasive method to monitor the oxygen saturation of the blood ❖ Does not replace ABGs ❖ Normal level is 95% to 100% ❖ May be unreliable Copyright © 2018 Wolters Kluwer · All Rights Reserved Health History ❖ Focus on the patient’s presenting problem and associated symptoms ❖ Explore the patient’s health, medical conditions, injuries, hospitalizations, surgeries, allergies, and current medications ❖ Assess for risk factors and genetic factors that may contribute to the patient’s lung condition Copyright © 2018 Wolters Kluwer · All Rights Reserved Physical Assessment ❖ General appearance may give clues to respiratory status o Clubbing of the fingers o Skin color ❖ Routine examination of the upper airway ❖ Assessment of the lower respiratory structures Copyright © 2018 Wolters Kluwer · All Rights Reserved Clubbing Copyright © 2018 Wolters Kluwer · All Rights Reserved Skin Color Copyright © 2018 Wolters Kluwer · All Rights Reserved Diagnostic Tests ❖ Pulmonary function tests, refer to Table 20-8 ❖ Arterial blood gases ❖ Sputum tests ❖ Chest x-ray ❖ Computed tomography (CT) ❖ Magnetic resonance imaging (MRI) Copyright © 2018 Wolters Kluwer · All Rights Reserved Diagnostic Tests #2 ❖ Fluoroscopic studies and angiography ❖ Radioisotope procedures—lung scans ❖ Endoscopic bronchoscopy, refer to Figure 20-13 ❖ Endoscopic thoracoscopy, refer to Figure 20-14 ❖ Thoracentesis ❖ Biopsies Copyright © 2018 Wolters Kluwer · All Rights Reserved