Respiratory System: Assessment
1. Identify the anatomy and physiology of the respiratory system.
2. Distinguish landmarks that guide assessment of the respiratory system.
3. Develop questions to be used when completing the focused interview.
4. Explain client preparation for assessment of the respiratory system.
5. Describe the techniques required for assessment of the respiratory system.
6. Differentiate normal from abnormal findings in physical assessment.
7. Describe developmental, psychosocial, cultural, and environmental variations in assessment techniques and findings.
8. Discuss the focus areas related to the overall health of the respiratory system as presented in Healthy People 2010.
9. Apply critical thinking in selected simulations related to physical assessment of the respiratory system.
Anatomy and physiology review
Gathering the data
adventitious sounds Added sounds superimposed on normal breath sounds and often indicative of underlying airway problems or diseases of the cardiovascular or respiratory systems.
angle of Louis (Sternal angle) A horizontal ridge formed at the point where the manubrium joins the body of the sternum.
bronchial sounds Loud, high-pitched sounds heard next to the trachea and are longer on exhalation.
bronchophony Auscultation of voice sounds, patient says "ninety-nine" and normal lung sound will be muffled.
bronchovesicular sounds Sounds that are medium in loudness and pitch, heard between the scapula, posteriorly and next to the sternum, and anteriorly upon inhalation and exhalation.
dullness The level of the diaphragm during quiet respiration.
dyspnea A change in normal breathing pattern, producing shortness of breath or difficulty in breathing.
egophony Ausculation of voice sounds, patient says "E", normal lungs sound like "eeeeee".
eupnea The regular, even-depth, rhythmic pattern of inspiration and expiration; normal breathing.
fremitus The palpable vibration on the chest wall when the client speaks.
landmarks Thoracic reference points and specific anatomical structures used to help provide an exact location for the assessment findings and an accurate orientation for documentation of findings.
manubrium The superior portion of the sternum.
mediastinum Part of the thorax, or thoracic cavity, that contains the heart, trachea, esophagus, and major blood vessels of the body.
rales/crackles Discontinuous sounds which are intermittent, nonmusical, and brief.
resonance The usual sound in the thorax, a long, low-pitched hollow sound.
respiratory cycle Consists of an inspiratory phase and an expiratory phase of breathing.
rhonchi (Sonorous Wheezes) Sounds that are low-pitched with a snoring quality.
tracheal sounds Harsh, high-pitched sounds heard over the trachea when the client inhales and exhales.
vesicular sounds Sounds are soft and low-pitched and heard over the remainder of the lungs, longer on inhalation than exhalation.
wheezes (Sibilant) Sounds that are high-pitched with a shrill quality.
whispered pectoriloquy Auscultation of voice sounds, patient whispers "one, two, three", normal lung sounds will be faint, almost indistinquishable.
Obtaining accurate information from the client is important in determining the type and severity of pulmonary problems.
Age, gender, and race can affect the physical and diagnostic findings related to respiratory function. Many of the diagnostic studies relevant to respiratory disorders (e.g., pulmonary function tests) use these demographic data for determining predicted normal values.
PERSONAL AND FAMILY HISTORY
The nurse asks clients about their own respiratory history and that of their family members. The family history is obtained to consider respiratory disorders with a genetic component, such as cystic fibrosis, some lung cancers, and alpha,-antitrypsin deficiency (one risk factor for emphysema). Clients with asthma often have a family history of allergic symptoms and reactive airways. The nurse assesses for a history of infectious disease, such as tuberculosis, and considers that family members may have similar environmental or occupational exposures.
The nurse questions the client about the use of cigarettes, cigars, pipe tobacco, marijuana, and other controlled substances, and he or she notes whether the client has passive exposure to smoke in the home or workplace. If the client smokes, the nurse asks for how long, how many packs a day, and whether the client has quit smoking (and how long ago). The smoking history is documented in pack-years (number of packs smoked per day multiplied by number of years). Because the client may have guilt or denial about this habit, the nurse assumes a nonjudgmental attitude during the interview.
Smoking induces anatomic changes in the large and peripheral airways, and these changes lead to varying degrees of airway obstruction. Men who continue to smoke experience a more rapid decline in their pulmonary function than do non-smokers. The pulmonary function of clients who have quit smoking for 2 or more years appears to decline less rapidly than in clients who continue to smoke.
The nurse asks about medications taken for breathing problems and about drugs taken for other conditions. For example, a cough can be a side effect of the angiotensin-converting enzyme (ACE) inhibitors. The nurse determines which over-the-counter medications (e.g., cough syrups, antihistamines, decongestants, inhalants, and nasal sprays) the client is using.
The use of home remedies also is assessed. The client is asked about past medication use and the reason for its discontinuation. For example, he or she may have used numerous bronchodilator metered dose inhalers but may prefer one particular drug for relieving breathlessness. In addition, some medications for other conditions can cause permanent changes in pulmonary function. For example, clients may have residual pulmonary fibrosis if they received bleomycin (Blenoxane) as chemotherapy for cancer or amiodarone (Cordarone) for cardiac problems.
Information about allergies is important to the respiratory history. The nurse determines whether the client has any known allergies to environmental substances such as foods, dust, molds, pollen, bee stings, trees, grass, animal dander and saliva, or medications. The client is asked to explain a specific allergic response. For example, does he or she wheeze, have trouble breathing, cough, sneeze, or experience rhinitis after exposure to the allergen? Has he or she ever been treated for an allergic response? If the client has received treatment for allergies, the nurse asks about the circumstances leading up to the need for treatment, the type of treatment, and the response to treatment.
Travel and Area of Residence
Travel and area of residence may be relevant for a history of exposure to certain diseases. For example, histoplasmosis, a fungal disease caused by inhalation of contaminated dust, is found in the central United States, the Mississippi and Missouri river valleys, and Central America. Coccidioidomycosis, another fungal disease, is found predominantly in the western and southwestern United States, Mexico, and portions of Central America.
An evaluation of the client's diet history may reveal allergic reactions to certain foods or preservatives. Signs and symptoms range from rhinitis, chest tightness, weakness, shortness of breath, urticaria, and severe wheezing to loss of consciousness. The nurse documents in a prominent location of the client's record any known allergies and the specific type of allergic response experienced. The client is asked about his or her usual food intake and whether any symptoms occur with eating. Malnutrition may occur if he or she has difficulty breathing during eating or the food preparation process.
OCCUPATIONAL HISTORY AND SOCIOECONOMIC STATUS
The nurse considers the home, community, and workplace for environmental factors that could cause or contribute to lung disease. Occupational pulmonary diseases include pneumoconiosis, which results from the inhalation of dust (e.g., coal dust, stone dust, silicone dust); toxic lung injury; and hypersensitivity disease (e.g., hypersensitivity to latex). The occupational history includes the exact dates of employment and a brief job description. Exposure to industrial dusts of any type or to the noxious chemicals found in smoke and fumes may cause respiratory disease. Coal miners, stone masons, cotton handlers, welders, potters, plastic and rubber manufacturers, printers, farm workers, and steel foundry workers are among the most susceptible.
The nurse obtains information about the home and living conditions, such as the type of heat used (e.g., gas heater, wood-burning stove, fireplace, and kerosene heater) and exposure to environmental irritants (e.g., noxious fumes, chemicals, animals, birds, and air pollutants). The client is asked about hobbies and leisure activities. Pastimes such as painting, working with ceramics, model airplane building, furniture refinishing, or woodworking may have exposed the client to harmful chemical irritants.
CURRENT HEALTH PROBLEMS
Whether the pulmonary problem is acute or chronic, the chief complaint is likely to include cough, sputum production, chest pain, and shortness of breath at rest or on exertion. During the interview, the nurse explores the history of the present illness, preferably in chronologic order. This analysis of the problem(s) includes the following:
• Progressing and radiating patterns
• Quality and number of symptoms
• Aggravating and relieving factors
• Associated signs and symptoms
Cough is the cardinal sign of respiratory disease. The nurse asks the client how long the cough has persisted (e.g., 1 week, 3 months) and whether it occurs at a specific time of day (e.g., on awakening in the morning, which is common in smokers) or in relation to any physical activity. The nurse determines whether the cough is productive or nonproductive, congested, dry, tickling, or hacking.
Sputum production is an important symptom associated with coughing. The nurse notes the duration, color, consistency, odor, and amount of sputum. Sputum may be clear, white, tan, gray or, if infection is present, yellow or green.
The nurse describes the consistency of sputum as thin, thick, watery, or frothy. Smokers with chronic bronchitis have mucoid sputum because of chronic stimulation and hypertrophy of the bronchial glands. Voluminous, pink, frothy sputum is characteristic of pulmonary edema. Pneumococcal pneumonia is often associated with rust-colored sputum, and foul-smelling sputum is often found in anaerobic infections such as a lung abscess. Blood in the sputum (hemoptysis) is most commonly noted in clients with chronic bronchitis or bronchogenic carcinoma. Clients with tuberculosis, pulmonary infarction, bronchial adenoma, or lung abscess may expectorate grossly bloody sputum.
Sputum can be quantified by describing its production in terms of measurements such as
teaspoon, tablespoon, and cups or fractions of cups. Normally, the
tracheobronchial tree can produce up to
A detailed description of chest pain helps the nurse differentiate pleural, musculoskeletal, cardiac, and gastrointestinal pain. Because the perception of pain is subjective, pain is analyzed in relation to the characteristics described in the history of the present illness. Coughing, deep breathing, or swallowing usually worsens chest wall pain.
The perception of dyspnea (difficulty in breathing or breathlessness) is subjective and varies among clients. A client's perception may not be consistent with the severity of the presenting problem. Therefore the nurse determines the type of onset (slow or abrupt), the duration (number of hours, time of day), relieving factors (changes of position, medication use, activity cessation), and evidence of audible sounds (wheezing, crackles, stridor).
The nurse tries to quantify dyspnea by asking whether this symptom interferes with activities of daily living (ADLs) and, if so, how severely. For example, is the client breathless while dressing, showering, shaving, or eating? Does dyspnea on exertion occur after walking one block or climbing one flight of stairs?
The nurse asks about paroxysmal nocturnal dyspnea (PND), which involves intermittent dyspnea during sleep, and about orthopnea, which is demonstrated by a shortness of breath that occurs when lying down but is relieved by sitting up. These two conditions are commonly associated with chronic pulmonary disease and left ventricular failure. In PND, the client has a sudden onset of breathing difficulty that is severe enough to awaken the client from sleep.
ASSESSMENT OF THE NOSE AND SINUSES
The nurse inspects the client's external nose for deformities or tumors and inspects the nostrils for symmetry of size and shape. Nasal flaring may indicate an increased respiratory effort. To observe the interior nose, the nurse asks the client to tilt the head back for a penlight examination. The nurse may use a nasal speculum and nasopharyngeal mirror for a more thorough examination of the nasal cavity.
The nurse inspects for color, swelling, drainage, and bleeding. The mucous membrane of the nose normally appears redder than the oral mucosa, but it may appear pale, engorged, and bluish gray in clients with allergic rhinitis. The nasal septum is checked for evidence of bleeding, perforation, or deviation. Some degree of septal deviation is common in most adults and appears as an S shape, inclining toward one side or the other. A perforated septum is noted if the light shines through the perforation into the opposite nostril; this condition is often found in cocaine users. Nasal polyps, a common cause of obstruction, appear as pale, shiny, gelatinous structures attached to the turbinates.
The nurse occludes one nare at a time to check whether air moves through the nonoccluded side easily. The nose and paranasal sinuses are palpated to detect tenderness or swelling. Only the frontal and maxillary sinuses are readily accessible to clinical examination because the ethmoid and sphenoid sinuses lie deep within the skull. Using the thumbs, the nurse checks for sinus tenderness by pressing upward on the frontal and maxillary areas; both sides are assessed simultaneously. Tenderness in these areas suggests inflammation or acute sinusitis. Tenderness in response to tapping a finger over these areas also indicates inflammation.
Transillumination of the sinuses may be used to detect sinusitis. In a darkened room, the nurse places the bulb of a penlight on the client's cheek (just under the corner of the eye) and observes for light penetration through the roof of the mouth. Normally, a faint glow of light through the bone outlines the sinus. Transillumination is absent or decreased in sinusitis. However, this test is not conclusive for sinusitis.
ASSESSMENT OF THE PHARYNX, TRACHEA, AND LARYNX
Examination of the pharynx begins with inspection of the external structures of the mouth. To examine the structures of the posterior pharynx, the nurse uses a tongue depressor to press down one side of the tongue at a time (to avoid stimulating the gag reflex). As the client says "ah," the nurse notes the rise and fall of the soft palate and uvula and observes for color and symmetry, evidence of discharge (postnasal drainage), edema or ulceration, and tonsillar enlargement or inflammation.
The neck is inspected for symmetry, alignment, masses, swelling, bruises, and the use of accessory neck muscles in breathing. Lymph nodes are palpated for size, shape, mobility, consistency, and tenderness. Tender nodes are usually movable and suggest inflammation. Malignant nodes are often hard and are fixed to the surrounding tissue.
The nurse gently palpates the trachea for deviation, mobility, tenderness, and masses. Firm palpation may elicit coughing or gagging. The space on either side of the trachea should be equal. Many pulmonary disorders cause the trachea to deviate from the midline. Tension pneumothorax, large pleural effusion, mediastinal mass, and neck tumors push the trachea away from the affected area, whereas pneumonectomy, fibrosis, and atelectasis cause a pull toward the affected area. Decreased tracheal mobility may occur with carcinoma or fibro-sis of the mediastinum.
The larynx is usually examined by a specialist with a laryngoscope. The nurse may observe an abnormal voice, especially hoarseness, when there are abnormalities of the larynx.
ASSESSMENT OF THE LUNGS AND THORAX
Inspection of the chest begins with an assessment of the anterior and posterior thorax. If possible, the client is in a sitting position during the assessment. He or she should be undressed to the waist and draped for privacy and warmth. The chest is observed by comparing one side with the other. The nurse works from the top (apex) and moves downward toward the base while inspecting for discoloration, scars, lesions, masses, and spinal deformities such as kyphosis, scoliosis, and lordosis.
The nurse observes the rate, rhythm, and depth of inspirations as well as the symmetry of chest movement. An impaired movement or unequal expansion may indicate an underlying disease of the lung or the pleura. The nurse observes the type of breathing (e.g., pursed-lip or diaphragmatic breathing) and the use of accessory muscles. In observing respiration, the nurse documents the duration of the inspiratory (I) and expiratory (E) phases. The ratio of these phases (the I/E ratio) is normally 1:2. A prolonged expiratory phase indicates an obstruction of air outflow and is often seen in clients with asthma or chronic obstructive pulmonary disease (COPD).
The nurse examines the shape of the client's chest and compares the anteroposterior (AP) diameter with the lateral diameter. This ratio normally ranges from 1:2 to approximately 5:7, depending on body build. The ratio increases to 1:1 in clients with emphysema, which results in the typical barrel chest appearance.
Normally, the ribs slope downward. However, clients with air trapping in the lungs caused by chronic asthma or emphysema have little or no slope to the ribs (i.e., the ribs are more horizontal).
The nurse also checks for abnormal retractions of the intercostal spaces during inspiration, which indicate airflow obstruction. These retractions may be due to fibrosis of the underlying lung, severe acute asthma, emphysema, or tracheal or laryngeal obstruction.
Palpation of the chest occurs after inspection. Palpation allows the nurse to assess respiratory movement symmetry and observable abnormalities, to identify areas of tenderness, and to elicit vocal or tactile fremitus (vibration).
The nurse assesses thoracic expansion by placing the thumbs posteriorly on the spine at the level of the ninth ribs and extending the fingers laterally around the rib cage. As the client inhales, both sides of the chest should move upward and outward together in one symmetric movement, and the nurse's thumbs move apart. On exhalation, the thumbs should come back together as they return to the midline. Decreased movement on one side (unilateral or unequal expansion) may be a result of pain, trauma, or pneumothorax (air in the pleural cavity). Respiratory lag or slowed movement on one side may indicate the presence of a pulmonary mass, pleural fibrosis, atelectasis, pneumonia, or a lung abscess.
The nurse palpates any abnormalities found on inspection (e.g., masses, lesions, bruises, and swelling). The nurse also palpates for tenderness, particularly if the client has reported pain. Crepitus (subcutaneous emphysema) is felt as a crackling sensation beneath the fingertips and should be documented, especially if it occurs around a wound site or if a pneumothorax is suspected. Crepitus indicates that air is trapped within the tissues.
Tactile (vocal) fremitus is a vibration of the chest wall produced when the client speaks. This vibration can be palpated on the chest wall. To elicit tactile fremitus, the nurse places the palm or the base of the fingers against the client's chest wall and instructs him or her to say the number 99. Using the same hand and moving from the apices to the bases, the nurse compares vibrations from one side of the chest with those from the other side. Palpable vibrations are transmitted from the tracheobronchial tree, along the solid surface of chest wall, and to the nurse's hand.
The nurse notes the symmetry of the vibrations and areas of enhanced, diminished, or absent fremitus. Fremitus is decreased if the transmission of sound waves from the larynx to the chest wall is slowed. This situation can occur when the pleural space is filled with air (pneumothorax) or fluid (pleural effusion) or when the bronchus is obstructed. Fremitus is increased over large bronchi because of their proximity to the chest wall. Disease processes such as pneumonia and abscesses increase the density of the thorax and enhance transmission of the vibrations.
The nurse uses percussion to assess for pulmonary resonance, the boundaries of organs, and diaphragmatic excursion. Percussion involves tapping the chest wall, which sets the underlying tissues into motion and produces audible sounds. The nurse places the distal joint of the middle finger of the less dominant hand firmly over the intercostal space to be percussed. No other part of the nurse's hand touches the client's chest wall because doing so absorbs the vibrations. The middle finger of the dominant hand then delivers quick, sharp strikes to the distal joint of the positioned finger. The nurse maintains a loose, relaxed wrist while delivering the taps with the tip of the finger, not the finger pad. This technique is repeated two or three times to determine the intensity, pitch, quality, and duration of the sound produced. Long fingernails limit the ability to percuss.
Percussion produces five distinguishable notes. These sounds assist the nurse in determining the
density of the underlying structures (i.e., whether the lung tissue contains
air or fluid or is solid). Percussion of the thorax is performed over the
intercostal spaces because percussing the sternum, ribs, or scapulae yields
sound indicating solid bone. Percussion penetrates only 2 to
Percussion begins with the client sitting in an upright position. The
nurse assesses the posterior thorax first and proceeds
systematically, beginning at the apex and working toward the base. The apex of
the lung extends anteriorly approximately ¾ to 1 ½ inches (2 to
The nurse assesses diaphragmatic excursion by instructing the client to
"take a deep breath and hold it" while percussing downward until dullness is
noted at the lower border of the lung. Normal resonance of the lung stops at
the diaphragm, where the sound becomes dull; this site is marked. The nurse repeats the process after instructing the
client to "let out all your breath and
hold." The difference between the two markings or sounds is the
diaphragmatic excursion, which may range from 1 to
The nurse continues to assess the thorax with percussion of the anterior and lateral chest. The percussion note changes from resonance of the normal lung to dullness at the borders of the heart and liver. The presence of fluid or solid material is indicated by a dull percussion note over lung tissue (as occurs with pneumonia, pleural effusion, fibrosis, atelectasis, and tumors).
Auscultation includes listening for normal breath sounds, adventitious sounds, and voice sounds. Auscultation provides information about the flow of air through the tracheo-bronchial tree and helps the listener to identify fluid, mucus, or obstruction in the respiratory system. The diaphragm of the stethoscope is designed to detect high-pitched sounds.
Auscultation begins with the client sitting in an upright position. With the stethoscope pressed firmly against the client's chest wall (clothing can distort or muffle sounds), the nurse instructs him or her to breathe slowly and deeply through an open mouth. (Breathing through the nose would set up turbulent sounds that are transmitted to the lungs.) A systematic approach is used, beginning at the apices and moving down through the intercostal spaces to the bases. Listening over bony structures is avoided while auscultating the thorax posteriorly, laterally, and anteriorly. The nurse listens to a full respiratory cycle, noting the quality and intensity of the breath sounds. The client is observed for signs of lightheadedness or dizziness caused by hyperventilation during auscultation. If these symptoms occur, the client is told to breathe normally for a few minutes.
NORMAL BREATH SOUNDS
Normal breath sounds are produced as air vibrates while passing through the respiratory passages from the larynx to the alveoli. Breath sounds are identified by their location, intensity, pitch, and duration within the respiratory cycle (e.g., early or late inspiration and expiration). Normal breath sounds are known as bronchial or tubular (harsh hollow sounds heard over the trachea and mainstem bronchi), bronchovesicular (heard over the branching bronchi), and vesicular (a soft rustling sound heard in the periphery over small bronchioles). The nurse describes these sounds as normal, increased, decreased (diminished), or absent.
When bronchial breath sounds are heard peripherally, they are abnormal. This increased sound occurs when centrally generated bronchial sounds are transmitted to an area of increased density, such as in clients with atelectasis, tumor, or pneumonia. When audible in an abnormal location, bronchovesicular breath sounds may indicate normal aging or an abnormality such as pulmonary consolidation and chronic airway disease.
ADVENTITIOUS BREATH SOUNDS
Adventitious sounds are additional breath sounds superimposed on normal sounds, and they indicate pathologic changes in the tracheobronchial tree. Table 27-6 classifies and describes adventitious sounds: crackle, wheeze, rhonchus, and pleural friction rub. Adventitious sounds vary in pitch, intensity, duration, and the phase of the respiratory cycle in which they occur. The nurse documents exactly what is heard on auscultation.
If the nurse discovers abnormalities during the physical assessment of the lungs and thorax, the client is assessed for vocal resonance. Auscultation of voice sounds through the normally air-filled lung produces a muffled, unclear sound because sound vibrations travel poorly through air. Vocal resonance is increased when the sound must travel through a solid or liquid medium, as it does in clients with a consolidated area of the lung, pneumonia, atelectasis, pleural effusion, tumor, or abscess.
BRONCHOPHONY. Bronchophony is the abnormally loud and clear transmission of voice sounds through an area of increased density. For assessment of bronchophony, the client repeats the number 99 while the nurse systematically auscultates the thorax.
WHISPERED PECTORILOQUY. Whispered pectoriloquy is the enhanced voice heard through the chest wall. It is much more sensitive than bronchophony and is perceived by having the client whisper the number sequence one, two, three. Whispered words normally sound faint and indistinct. If they are heard loudly and distinctly, the nurse suspects consolidation of lung tissue.
EGOPHONY. Egophony is another form of abnormally enhanced vocal resonance and has a high-pitched, bleating, nasal quality. The nurse auscultates the thorax while the client repeats the letter E. Egophony exists when this letter is heard as a flat, nasal sound of A through the stethoscope. This abnormal sound indicates an area of consolidation, pleural effusion, or abscess.
OTHER INDICATORS OF RESPIRATORY ADEQUACY
The nurse evaluates additional indicators of respiratory adequacy because gas exchange affects all body systems. Some indicators (e.g., cyanosis) indicate immediate oxygenation problems. Other changes (e.g., clubbing, weight loss, unevenly developed muscles) reflect a more long-standing oxygenation problem.
Skin and Mucous Membranes
The skin and mucous membranes are assessed for the presence of pallor or cyanosis, which could indicate inadequate ventilation. Areas to assess include the nail beds and the mucous membranes of the oral cavity. The fingers are examined for clubbing, which would indicate hypoxia of long duration.
The nurse observes the client for muscle development and general body build. Long-term respiratory problems are often associated with an inability to maintain body weight and a loss of general muscle mass. Arms and legs may appear thin or poorly muscled. The muscles of the neck and chest may be hypertrophied, especially in the client with chronic obstructive pulmonary disease (COPD).
The nurse observes how easily the client moves and whether he or she is short of breath while resting or becomes short of breath when walking 10 to 20 steps. As the client speaks, the nurse observes how often he or she pauses for breath between words.
The nurse assesses aspects of the client's lifestyle that may significantly affect respiratory function. Some respiratory conditions may be worsened by stress. The nurse asks about present life stresses and usual coping mechanisms.
Chronic respiratory illnesses may cause changes in family roles and relationships, social isolation, financial problems, and unemployment or disability. By discussing coping mechanisms, the nurse assesses the client's reaction to these psychosocial stressors and discovers strengths and ineffective behaviors. For example, the client may react to stress with dependence on family members, withdrawal, or noncompliance with interventions. After completing the psychosocial assessment, the nurse assists the client in determining the support systems available to help cope with respiratory impairment.
I LABORATORY TESTS
A red blood cell count provides data regarding the transport of oxygen from the lungs. A hemoglobin deficiency directly affects tissue oxygenation because hemoglobin transports oxygen to the cells and could cause hypoxemia.
Arterial blood gas (ABG) analysis assesses oxygenation (partial pressure of arterial oxygen [Pao2]), alveolar ventilation (partial pressure of arterial carbon dioxide [Paco2]), and acid-base balance. Blood gas studies provide valuable information for monitoring treatment results, adjusting oxygen therapy, and evaluating the client's responses to treatment and therapy, such as during weaning from mechanical ventilation.
Sputum specimens obtained by expectoration or tracheal suctioning assist in the identification of pathogenic organisms or abnormal cells, such as in a malignancy or a hypersensitivity state. Sputum culture and sensitivity analyses identify bacterial infection with either gram-negative or gram-positive organisms and determine the vulnerability to specific antibiotics. Cytologic examination is performed on sputum to help diagnose malignant lesions by identifying cancer cells. Benign conditions, such as a hypersensitivity state, may also be identified by cytologic testing. Eosinophils and Curschmann's spirals (a mucous form) are often found by cytologic study in clients with allergic asthma.
Chest x-ray examinations are performed for clients with respiratory tract disorders to evaluate the present status of the chest and to provide a baseline for comparison with future changes. Standard chest x-ray examinations are performed from posteroanterior (PA; back to front) and left lateral (LL) projections. Portable chest x-ray studies (taken anteroposterior [AP], front to back) cost more, and the films produced are of lower quality and are more difficult for the radiologist to interpret. Consecutive, 10-mm cross-sectional views of the thorax and produces a three-dimensional assessment of the lungs and thorax.
Fat, cystic, and solid tissue can be distinguished with CT. By adding an intravenously injected contrast agent, vessels and other soft tissue structures can be identified. CT is especially valuable in studying the mediastinum, hilar region, and pleural space. The newer high-resolution CT (HRCT) uses 1.5- to 2-mm "slices" to assist in assessing bronchial abnormalities, interstitial disease, and emphysema. Nursing interventions for the client undergoing CT include education about the procedure and determination of the client's sensitivity to the contrast medium (very important for anaphylaxis prevention).
Ventilation and Perfusion Scanning
A ventilation and perfusion scan (V/Q scan) identifies the areas of the lung being ventilated and the distribution of pulmonary blood. It is used primarily to support or rule out a diagnosis of pulmonary embolism.
To perform the study, the physician first injects a radionuclide with the client in a supine position and then takes six perfusion views: anterior, posterior, right and left lateral, and two obliques. If the perfusion scan is normal, there is no reason to continue with the ventilation scan. Otherwise, the client inhales a radioactive gas or radioaerosol, and the lung is scanned continuously—as the gas makes its way into the lungs (the "wash-in" phase), once the gas has reached equilibrium within the lungs, and then while the gas is leaving the lungs (the "wash-out" phase).
The nurse teaches the client about the procedure and explains that the radioactive substance clears from the body in approximately 8 hours.
OTHER NONINVASIVE DIAGNOSTIC TESTS
Pulse oximetry identifies hemoglobin saturation. Usually hemoglobin is almost 100% saturated with oxygen. The pulse oximeter uses a wave of infrared light and a sensor placed on the client's finger, toe, nose, earlobe, or forehead. Ideal normal pulse oximetry values are 95% to 100%; values may be a little lower in older clients and in clients with dark skin. To avoid confusion with the Pao2 values from arterial blood gases, pulse oximetry readings are recorded as the Sao2 (arterial oxygen saturation), or Spo2.
A pulse oximetry reading can alert the nurse to desaturation before clinical signs occur (e.g., dusky skin, pale mucosa, and nail beds). The nurse considers client movement, hypothermia, decreased peripheral blood flow, ambient light (sunlight, infrared lamps), decreased hemoglobin, edema, and fingernail polish as possible causes for low readings. Covering the sensor or changing its positioning could yield better accuracy if too much ambient light is present.
Results lower than 91% (and certainly below 86%) constitute an emergency and necessitate immediate treatment. When the Sao2 is below 85%, the tissues of the body have a difficult time becoming oxygenated. An Sao2 of less than 70% is usually life threatening, but in some cases values below 80% may be life threatening. Pulse oximetry is less accurate at lower values.
Pulmonary Function Tests
Pulmonary function tests (PFTs) evaluate lung function and dysfunction and include studies such as lung volumes and capacities, flow rates, diffusion capacity, gas exchange, airway resistance, and distribution of ventilation. The physician interprets the results by comparing the client's data with normal findings predicted according to age, gender, race, height, weight, and smoking status.
PFTs are useful in screening clients for pulmonary disease even before the onset of signs or symptoms. Serial testing provides objective data that may be used as a guide to treatment (e.g., changes in pulmonary function can support a decision to continue, change, or discontinue a specific therapy). Preoperative evaluation with PFTs may identify the client at risk for postoperative pulmonary complications. One of the most common reasons for performing such tests is to determine the cause of dyspnea. When performed while the client exercises, PFTs help to determine whether dyspnea is caused by pulmonary or cardiac dysfunction or by muscle deconditioning. These tests are also useful for determining the effect of the client's occupation on pulmonary function and for evaluating any related disability for legal purposes.
CLIENT PREPARATION. The nurse prepares the client for PFTs by explaining the purpose of the tests for planning care. He or she is advised not to smoke for 6 to 8 hours before testing. According to institutional policy and procedure, bronchodilator medication is withheld for 4 to 6 hours before the test. The client with respiratory impairment often fears further breathlessness and is usually anxious before these "breathing" tests. The nurse helps to reduce apprehension by describing what will be experienced during and after the testing.
PROCEDURE. PFTs can be performed at the bedside or in the respiratory laboratory. The client is asked to breathe through the mouth only. A nose clip may be used to prevent air from escaping. The client performs different breathing maneuvers while measurements are obtained.
FOLLOW-UP CARE. Because numerous breathing maneuvers are performed during PFTs, the nurse observes for increased dyspnea or bronchospasm after such studies. The nurse documents whether bronchodilator medication was administered during testing and alters the client's medication schedule as indicated.
Exercise, or activity in general, increases metabolism and gas transport as energy is generated. These tests are performed on a treadmill or bicycle or by a self-paced 12-minute walking test. The normal client's exercise is limited by hemodynamic factors, whereas the pulmonary client is limited by ventilatory capacity, pulmonary gas exchange compromise, or both. The nurse explains exercise testing and assures the client of close monitoring by trained professionals throughout the test.
Skin tests are used in combination with other diagnostic data to identify various infectious diseases (e.g., tuberculosis), viral diseases (e.g., mononucleosis and mumps), and fungal diseases (e.g., coccidioidomycosis and histoplasmosis). The presence of allergic hypersensitivity and the status of the immune system can be demonstrated through skin testing. Exposure to the allergen or organism used in testing produces a specific reaction (delayed hypersensitivity reaction) of the client's immune system.
Magnetic Resonance Imaging
Magnetic resonance imaging (MRI) is used in the diagnosis of respiratory system disorders to provide information about the type and condition of the tissues being imaged along any plane inside the body: vertically, horizontally, and diagonally. This costly procedure requires little client preparation other than the removal of all metal objects. Because of the powerful magnets used in MRI, clients with pacemakers, aneurysm clips, inner-ear implants, cardiac valves, or any other metallic foreign objects in the body are not candidates for MRI.
The nurse informs the client of possible claustrophobia and discomfort from lying on a hard, cool table inside the magnet's small cylinder. The nurse instructs the client in the use of relaxation techniques and imagery to help decrease these sensations. Sedation may be necessary in some cases. The nurse explains that the noises heard during the examination are the natural, rhythmic sounds of radiofrequency pulses. These noises may range from barely audible to noticeable.
OTHER INVASIVE DIAGNOSTIC TESTS
Endoscopic diagnostic studies to assess respiratory disorders include bronchoscopy, laryngoscopy, and mediastinoscopy. The most common complications are those related to the medications and bleeding.
Thoracentesis is used for diagnosis or treatment and involves the aspiration of pleural fluid or air from the pleural space. Microscopic examination of the pleural fluid helps in making a diagnosis. Pleural fluid may be drained to relieve pulmonary compression and the resultant respiratory distress caused by cancer, empyema, pleurisy, or tuberculosis. Thoracentesis is often followed by pleural biopsy to assist in further assessment of the parietal pleura. Thoracentesis also allows the instillation of medications into the pleural space.
CLIENT PREPARATION. Adequate client preparation is essential before thoracentesis to ensure cooperation during the procedure and to prevent complications. The nurse tells the client to expect a stinging sensation from the local anesthetic agent and a feeling of pressure when the needle is inserted. The nurse reinforces the importance of not moving during the procedure (avoiding coughing, deep breathing, or sudden movement) to avoid puncture of the visceral pleura or lung.
These positions widen the intercostal spaces and permit easy access to the pleural fluid. The nurse properly positions and physically supports the client. Pillows are used to make the client comfortable and to provide physical support.
Before the procedure, the nurse checks the client's history for hypersensitivity to local anesthetic agents and checks to make sure the client has signed an informed consent. The entire chest or back is exposed, and the aspiration site is shaved if necessary. The actual site depends on the volume and location of the effusion, which are determined by radiography and physical examination procedures such as percussion.
PROCEDURE. Thoracentesis is usually performed at the bedside, although ultrasonography or computed tomography may be used to guide it. After draping the client and cleaning the skin with a germicidal solution, the physician uses aseptic technique and injects a local anesthetic agent into the selected intercostal space. The nurse keeps the client informed of the procedure while observing for shock, pain, nausea, pallor, diaphoresis, cyanosis, tachypnea, and dyspnea.
The physician advances the short 18- to 25-gauge thoracentesis needle (with an attached syringe) into the pleural space. Gentle suction is applied as the fluid in the pleural space is slowly aspirated. A vacuum collection bottle is sometimes necessary to remove larger volumes of fluid. To prevent re-expansion pulmonary edema, usually no more than 1000 mL of fluid is removed at one time. If a pleural biopsy is to be performed, a second, larger needle with a cutting edge and collection chamber is used. After the physician withdraws the needle, pressure is applied to the puncture site, and a small sterile dressing is applied.
FOLLOW-UP CARE. After thoracentesis, the physician orders a chest x-ray study to rule out possible pneumothorax and subsequent mediastinal shift (shift of center thoracic structure toward one side). The nurse monitors the client's vital signs and auscultates breath sounds while noting absent or diminished sounds on the affected side. The puncture site and dressing are observed for leakage or bleeding. The nurse also assesses for other complications, such as reaccumulation of fluid in the pleural space, subcutaneous emphysema, pyrogenic infection, and tension pneumothorax. The client is encouraged to breathe deeply to promote reexpansion of the lung. The nurse documents the procedure, including the client's tolerance, the volume and character of the fluid removed, any specimens sent to the laboratory, the location of the puncture site, and respiratory assessment findings before, during, and after the procedure.
A lung biopsy is performed to obtain tissue for histologic analysis, culture, or cytologic examination. The physician uses tissue samples to make a definite diagnosis regarding the type of malignancy, infection, inflammation, or lung disease. Biopsy procedures include transbronchial biopsy (TBB) and transbronchial needle aspiration (TBNA), both of which are performed during bronchoscopy; transthoracic needle aspiration (percutaneous approach for areas not accessible by bronchoscopy); and open lung biopsy (in the operating room).
CLIENT PREPARATION. The client may have predetermined ideas about the outcome of the biopsy and may closely associate the terms biopsy and cancer. Therefore the nurse explains what to expect before and after the procedure and explores the client's feelings and fears. To reduce discomfort and anxiety, the physician may prescribe an analgesic or sedative before the procedure. The nurse informs the client undergoing percutaneous biopsy that discomfort is minimized with a local anesthetic agent but that a sensation of pressure may be experienced during needle insertion and tissue aspiration. Open lung biopsy is usually performed in the operating room with the client under general anesthesia, and the usual preoperative preparations apply.
PROCEDURE. Percutaneous lung biopsy may be performed in the client's room or in the radiology department after an informed consent has been obtained. Fluoroscopy, CT, or ultrasonography is often used to better visualize the area undergoing biopsy and to guide the procedure. Positioning of the client is similar to that for thoracentesis. The physician cleans the skin with an antibacterial agent and administers a local anesthetic agent. Under sterile conditions, the physician inserts a spinal-type 18- to 22-gauge needle through the skin into the desired area (e.g., tissue, nodule, or lymph node) and obtains the tissue needed for microscopic examination. The nurse applies a dressing after the procedure.
An open lung biopsy is performed in the operating room. The client undergoes a thoracotomy where lung tissue is exposed. At least two tissue specimens are taken (usually from an upper lobe and a lower lobe site). The surgeon places a chest tube to remove air and fluid so the lung can reinflate and then closes the chest.
FOLLOW-UP CARE. The nurse monitors the client's vital signs and breath sounds every 4 hours for 24 hours and assesses for signs of respiratory distress (e.g., dyspnea, pallor, diaphoresis, and tachypnea). Pneumothorax is a serious complication of needle biopsy and open lung biopsy, and therefore it is important for the nurse to report untoward signs and symptoms promptly. The nurse also monitors for hemoptysis (which may be scant and transient) or, in rare cases, for frank bleeding from vascular or lung trauma.