THE RESPIRATORY SYSTEM Pages 103-105 and 146-150 1
When the respiratory system is mentioned, people generally think of breathing, but breathing is only one of the activities of the respiratory system. The body cells need a continuous supply of oxygen for the metabolic processes that are necessary to maintain life. The respiratory system works with the circulatory system to provide this oxygen and to remove the waste products of metabolism. It also helps to regulate ph of the blood. 2
Respiration is the sequence of events that results in the exchange of oxygen and carbon dioxide between the atmosphere and the body cells. Every 3 to 5 seconds, nerve impulses stimulate the breathing process, or ventilation, which moves air through a series of passages into and out of the lungs. After this, there is an exchange of gases between the lungs and the blood. This is called external respiration. The blood transports the gases to and from the tissue cells. The exchange of gases between the blood and tissue cells is internal respiration. Finally, the cells utilize the oxygen for their specific activities. This is cellular metabolism, or cellular respiration. Together these activities constitute respiration. 3
Ventilation, or breathing, is the movement of air through the conducting passages between the atmosphere and the lungs. The air moves through the passages because of pressure gradients that are produced by contraction of the diaphragm and thoracic muscles. 4
Pulmonary Ventilation Pulmonary ventilation is commonly referred to as breathing. It is the process of air flowing into the lungs during inspiration (inhalation) and out of the lungs during expiration (exhalation). Air flows because of pressure differences between the atmosphere and the gases inside the lungs. Air, like other gases, flows from a region with higher pressure to a region with lower pressure. Muscular breathing movements and recoil of elastic tissues create the changes in pressure that result in ventilation. 5
Atmospheric Pressure Pulmonary ventilation involves three different pressures: 1. Intraalveolar (intrapulmonary) pressure 2. Intrapleural pressure 3. Atmospheric pressure is the pressure of the air outside the body. Intraalveolar pressure is the pressure inside the alveoli of the lungs. Intrapleural pressure is the pressure within the pleural cavity. These three pressures are responsible for pulmonary ventilation. 6
Inspiration Inspiration (inhalation) is the process of taking air into the lungs. It is the active phase of ventilation because it is the result of muscle contraction. During inspiration, the diaphragm contracts and the thoracic cavity increases in volume. This decreases the Intraalveolar pressure so that air flows into the lungs. Inspiration draws air into the lungs. 7
Expiration Expiration (exhalation) is the process of letting air out of the lungs during the breathing cycle. During expiration, the relaxation of the diaphragm and elastic recoil of tissue decreases the thoracic volume and increases the intraalveolar pressure. Expiration pushes air out of the lungs. 8
Under normal conditions, the average adult takes 12 to 15 breaths a minute. A breath is one complete respiratory cycle that consists of one inspiration and one expiration. An instrument called a spirometer is used to measure the volume of air that moves into and out of the lungs, and the process of taking the measurements is called spirometry. Respiratory (pulmonary) volumes are an important aspect of pulmonary function testing because they can provide information about the physical condition of the lungs. 9
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Respiratory capacity (pulmonary capacity) is the sum of two or more volumes. Factors such as age, sex, body build, and physical conditioning have an influence on lung volumes and capacities. Lungs usually reach their maximum in capacity in early adulthood and decline with age after that. 12
The respiratory conducting passages are divided into the upper respiratory tract and the lower respiratory tract. The upper respiratory tract includes the nose, pharynx, and larynx. The lower respiratory tract consists of the trachea, bronchial tree, and lungs. These tracts open to the outside and are lined with mucous membranes. In some regions, the membrane has hairs that help filter the air. Other regions may have cilia to propel mucus. 13
UPPER RESPIRATORY TRACT 14
LOWER RESPIRATORY TRACT 15
Nose and Nasal Cavities Pharynx Larynx & Trachea Bronchi, Bronchial Tree, and Lungs 16
Nose and Nasal Cavities Hairs and cilia line the nasal cavities and filter foreign particles and pathogens from the inhaled air. Mucus secreted by the mucosa traps substances in inhaled air, and the cilia move particles of mucus towards the pharynx to be swallowed or expectorated. Inhaled air is warmed and moistened as it passes over the mucosa. The 3 turbinate bones in each cavity cause air flow to become turbulent, which enhances contact of air with the mucosa. Sensory organ for the sense of smell (olfactory) 17
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Paranasal Sinuses Paranasal sinuses are air-filled cavities in the frontal, maxillae, ethmoid, and sphenoid bones. These sinuses, which have the same names as the bones in which they are located, surround the nasal cavity and open into it. They function to reduce the weight of the skull, to produce mucus, and to influence voice quality by acting as resonating chambers. 19
THE PHARYNX The pharynx, commonly called the throat, is a muscular tube about 12cm long, lying in front of the cervical vertebrae and behind the nose, mouth and larynx. It serves both the respiratory and digestive systems by receiving air from the nasal cavity and air, food, and water from the oral cavity. The pharynx is lined with mucous membrane and has 3 sections: Nasopharynx Oropharynx laryngopharynx 20
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THE LARYNX The larynx, commonly called the voice box or glottis, is the passageway for air between the pharynx above and the trachea below. It is formed by nine cartilages that are connected to each other by muscles and ligaments. 22
The larynx plays an essential role in human speech. During sound production, the vocal cords close together and vibrate as air expelled from the lungs passes between them. The false vocal cords have no role in sound production, but help close off the larynx when food is swallowed. The thyroid cartilage is the Adam's apple. The epiglottis acts like a trap door to keep food and other particles from entering the larynx. 23
THE TRACHEA The trachea, commonly called the windpipe, is the main airway to the lungs. It divides into the right and left bronchi at the level of the fifth thoracic vertebra, channelling air to the right or left lung. The hyaline cartilage in the tracheal wall provides support and keeps the trachea from collapsing. The posterior soft tissue allows for expansion of the oesophagus, which is immediately posterior to the trachea. 24
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Bronchi and Bronchial Tree In the mediastinum, at the level of the fifth thoracic vertebra, the trachea divides into the right and left primary bronchi. The bronchi branch into smaller and smaller passageways until they terminate in tiny air sacs called alveoli. 26
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THE LUNGS Are the 2 main organs of the respiratory system. They are divided into lobes, the left lung has 2 lobes and is smaller that the right lung (which has 3 lobes. Upper, middle and lower.), as the heart and its vessel take up more space in the left side of the chest. Each lung is surrounded by the pleura which is a membrane consisting of 2 layers that are lubricated by pleural fluid. 28
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The Alveoli Are microscopic air sacs in the lungs that form a surface area of about 70m² and are surrounded by a network of capillaries arising from the pulmonary arteries. The function of the alveoli is the interchange of O² and CO² between the air in the alveoli and the blood in the capillaries. 30
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MUSCLES OF VENTILATION The main muscles responsible for ventilation are the diaphragm and the internal and external intercostal Muscles. When we breath in the intercostal muscles move the ribs upwards and outwards and the diaphragm pushes downwards, this draws air into the expanded lungs. Breathing out is a passive process the recoil of the ribs and the lungs with the return of the diaphragm to a higher position squeeze the air out. 32
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EXTERNAL RESPIRATION Is the absorption of O² from the air into the blood and the excretion of CO² from the blood into the air. This takes place in the lungs 34
INTERNAL OR TISSUE RESPIRATOIN The O² is transferred from the blood to the tissues of the body which at the same time give up CO². This exchange takes place through the walls of the capillaries 35
Upper Respiratory Tract Infection (URTI) A URTI is marked by a fever, cough - dry or productive, sore throat, nasal congestion, ear ache, runny nose, streaming eyes and sneezing (Anderson et a. 1996). 36
Implications for Nursing Assistants Assist residents as symptoms arise and observe for any deterioration in condition. 37
CHRONIC AIRWAYS LIMITATION CAL is also know as: Chronic Obstructive Pulmonary Disease COPD Chronic Obstructive Airways Disease COAD and is a term used to describe several similar respiratory disorders that result in persistent obstruction of the bronchial airflow. 38
ASTHMA 39
ASTHMA 40
ASTHMA Chronic Asthma is a condition, which manifests itself by intermittent episodes of wheezing and dyspnoea. It is generally associated with a hypersensitive state of the bronchi, which may be attributable to an allergic response. (Miller et al. 1990). 41
Presenting Problems: Cough, or tightness in chest. Wheezing, shortness of breath. Dyspnoea. Anxiety, restlessness. Fatigue. Sputum- foamy, clear white too more thick and/or purulent. (Miller et al. 1990) 42
BRONCHITIS 43
BRONCHITIS Chronic Bronchitis is a hyper secretion of mucous and subsequent obstruction of airflow. (Miller et al 1990) 44
Presenting Problems Shortness of breath. Cough. Expectoration. Infection, necrosis and fibrosis of the respiratory tract. (Miller et al. 1990) 45
Implications for Nursing Assistants Never turn on oxygen or increase oxygen on a resident with breathing problems. Focus your care on conserving the minimal energy these residents possess. Assist with activities of daily living. Reassure the resident as problems with breathing lead to anxiety. Position resident to facilitate breathing - orthopnoeic position or sitting with arms crossed in front on table supported by pillow. 46
Maintain hydration and good nutrition. Assist with deep breathing and coughing exercises and postural drainage. Encourage resident to assess the impact of lifestyle choices, which affect their condition e.g. smoking. Sputum collection as required for culture in the event of infection. (Anderson 1996). 47
EMPHYSEMA 48
EMPHYSEMA Emphysema is a lung disease characterised by loss of lung elasticity due to destruction of the alveoli. It can occur as a result of chronic asthma and bronchitis (Miller et al. 1990). 49
Presenting Problems Severe shortness of breath. Cough, wheeze. Barrel chest, clubbing of fingers. Cardiac problems. (Miller et al. 1990) 50
LUNG CANCER 51
Lung Cancer Malignancy may arise in the bronchus as a primary tumour and is a common site for metastases (Miller et al. 1990) 52
Cough. Presenting Problems Haemoptysis. Discomfort, pain in chest. Wheeze. Repeated infections. General symptoms: anorexia, weight loss, fatigue. (Miller et al. 1990) 53
Implications for Nursing Assistants Emotional support of resident and significant others. Individual requirements for nutrition and fluids. Respond to symptoms as the need arises: cough and shortness of breath. Assist with activities of daily living. (Anderson et al 1996) 54
PNEUMONIA 55
Pneumonia Pneumonia is an inflammation of the lung with consolidation and exudation. It can be caused by bacteria or by viruses or by inhalation or by immobility. (Miller et al. 1990) 56
Presenting Problems Cough. High fever. Night sweats. Blood-streaked sputum. Increase in pulse and respiratory rate. (Miller et al. 1990) 57
PULMONARY TUBERCULOSIS 58
PULMONARY TUBERCULOSIS T.B is an infectious (tubercle bacillus), inflammatory, chronic lung disease (Miller et al. 1990). 59
Presenting Problems Malaise. Anorexia. Loss of weight. Fever. Cough. Night sweats. Purulent sputum. Haemoptysis. Pleurisy. (Miller et al. 1990) 60
Implications for Nursing Assistants Assist with hygiene: resident may feel uncomfortable after diaphoresis. Encourage resident to maintain fluid intake and good nutrition. Position for comfort - lay on affected side; splint chest. Assist resident to a position that facilitates breathing. Encourage ambulation or assist with passive exercises. Ensure standard precautions practiced when appropriate especially when disposing of sputum. (Anderson et al. 1996 & Luckman et al. 1990) 61