Values to know:
Hgb (M) 13.2-17.3 (F) 11.7-15.5 pH 7.35-7.45
Hct (M) 39%-50% (F) 35%-47% WBC 4000-11000
PaCO2 35-45 (32-48) platelets 150,000-440,000
HCO3 22-26 tidal volume 500 mL
SaO2 > 95% (critical <75%) Vital Capacity 4500 mL
PaO2 80-100 (critical <40)
RR 12-20 bpm
●gas exchange takes place at the alveoli
●compliance= how elastic the lungs are or how easily the lungs can be inflated
●respiratory volumes
○tidal volume= amount of air moving in and out of the lungs in one NORMAL breath
○Vital capacity= amount of air FORCIBLY exhaled in one breath after a maximum
inhalation.
○residual volume= air remaining in the lungs at the end of a forced (MAXIMUM) expiration
●Normally the primary respiratory stimulus is CO2 (when the PaCO2 is increased, ventilation is
initiated)
●When mucus is retained & pool in the lungs gas diffusion is decreased, which provides a medium
for bacteria growth
●Perfusion is the process of linking the venous blood flow to the alveoli
○is dependent on the volume of blood flowing from the right ventricle into and through the
pulmonary circulation.
●An SaO2 below 95% indicate respiratory difficulty.
●Oxyhemoglobin dissociation curve~ shows the affinity of Hgb for O2 at different O2 tensions
○when the curve shifts left - blood picks up oxygen more readily in the lungs
but delivers oxygen less readily to the tissues. this occurs in conditions that
raise the pH (alkalosis), when the body temperature declines
(hypothermia), and when PaCO2 levels decrease in the blood.
○When the curve shifts right- blood picks up oxygen less readily in the lungs
but delivers oxygen more readily to the tissues. This is seen as acidosis
(decrease in pH), hyperthermia and when the PaCO2 is increased.
●Altitude affects O2 transport- high levels in altitude have less O2 in the air.
○body compensates by
■increasing the # of RBC (which increases the O2 carrying
capacity of the blood)
■Hyperventilation
■Renal erythropoietic factor- released by the kidneys; generally takes about 4-5 days to actually
increase RBC production.
○problems w/ Oxygenation @ high altitudes
■decrease in O2 supply (causes decreased cardiac output and inadequate Hgb)
■Increase in body demand
ASSESSMENT :)
●obtain a good patient history
○freq. of upper respiratory infections
○immunization status
○medications (including OTC, herbs, & vitamins)
○lifestyle & environment
○habits (alcohol and tobacco)
○any changes in ADLs & activity related to respiratory problems?
○surgeries
●Physical assessment
○assess the airway for patency
○does client seem comfortable or distressed (positioning)
○vitals (do you have baselines to compare to?)
○inspect the neck for symmetry (trachea should be midline, are jugular veins distended?)
○assess lungs (even expansion, accessory muscle usage, chest pain, barrel chest,
tenderness)
○Auscultate breath sounds (should be present and equal bilaterally)
■adventitious breath sounds:
●crackles- usually heard on inspiration, but do not clear with cough, occur
when airway contains fluid (pneumonia atelectasis)
●wheezes- heard on inspiration and/or expiration, caused by air moving
thru narrowed passageways (asthma)
●pleural friction rub- heard primarily on inspiration over an area of pleural
inflammation, grating,scraping sound. (Pneumonia, tuberculosis,
asbestos-related diseases, certain cancers, and rheumatic diseases can
lead to friction of the pleural membranes and the sound they make
through a stethoscope)
○tactile fremitus- feeling increased vibrations when client says “99”
○Crepitus also known as subcutaneous emphysema, is a rare condition that is caused by
collapsed lung, or possibly a ruptured bronchial tube. ( also can happen in patients with
a chest tube)
○assess and evaluate any dyspnea
○check fingers for clubbing, and mucus membranes for cyanosis
○assess cough and sputum production (note characteristics of sputum if present)
●the primary indicators of respiratory distress are sputum production, cough, dyspnea, hemoptysis,
pleuritic chest pain, fatigue, change in voice and wheezing.
Diagnostic Tests: Hgb & Hct, BMP (fluid and electrolyte check), Chest x ray, sputum culture, skin
test(allergy, ppd), bronchoscopy, lung biopsy, thoracentesis, pulmonary function tests, exercise testing
Respiratory defense mechanisms
● filtration of air~ nasal hairs
● mucociliary clearance system~ escalator
○ action impaired by smoking, dehydration, inhalation of high oxygen concentrations,
infection and ingestion of some drugs ( atropine, anesthetics, alcohol, or cocaine)
○ COPD and cystic fibrosis/ freq lower respiratory infections destroy cilia.
● cough reflex
● reflex bronchoconstriction
● alveolar macrophages
Gerontologic Considerations ~ table 26-4 pg 504
● stiffening of chest wall, decrease in elastic recoil of lung, and a decrease in chest wall
compliance.
● costal cartilages calcify with aging and interfere with chest expansion.
● outward curvature of spine, lumbar curve flattens,
● chest may appear barrel shaped, may need to use accessory muscles to breathe
● decrease in # of functional alveoli
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