Lesson 1 The Respiratory Assessment & Function

Pulmonary ventilation

Moving air in and out of lungs through inspiration and expiration

Respiration

Gas exchange between atmospheric air and alveoli

Perfusion

Oxygenated blood passing through body tissues

Frontal sinus

Air-filled cavity in frontal bone above eyes

Sphenoidal sinus

Air-filled cavity in sphenoid bone

Nasal cavity

Space behind nose that warms and filters air

Nasopharynx

Upper portion of pharynx behind nasal cavity

Oropharynx

Middle portion of pharynx behind oral cavity

Laryngeal pharynx

Lower portion of pharynx connecting to larynx

Epiglottis

Cartilage flap that covers larynx during swallowing

Larynx

Voice box containing vocal cords

Trachea

Windpipe; rigid tube supported by cartilage rings

Right bronchus

Main airway to right lung

Left bronchus

Main airway to left lung (slightly longer and more horizontal)

Terminal bronchiole

Smallest conducting airways before respiratory zone

Right lung lobes

Three lobes

Left lung lobes

Two lobes

Mediastinum

Central compartment between lungs containing heart and vessels

Alveolus/Alveoli

Tiny air sacs where gas exchange occurs

Alveolar duct

Passage leading to alveoli

Parietal pleura

Outer membrane lining chest wall

Visceral pleura

Inner membrane covering lung surface

Pleural space

Thin fluid-filled space between pleural layers

Diaphragm

Primary respiratory muscle; separates thorax from abdomen

Manubrium of sternum

Superior (upper) portion of sternum

Body of sternum

Middle and largest portion of sternum

Xiphoid process

Inferior (lower) tip of sternum

Suprasternal notch

Depression at top of manubrium, between clavicles

Sternal angle

Junction between manubrium and body of sternum; important anatomical landmark where 2nd rib is located

2nd interspace

Space between 2nd and 3rd ribs

Costochondral junctions

Points where ribs meet their cartilages

Costal angle

Angle formed where lower ribs meet at midline (infrasternal angle)

Costal margin

Lower border of rib cage formed by cartilages of ribs 7-10

Clavicle

Collarbone; extends from sternum to shoulder

Acromion process

Lateral (outer) projection of scapula; forms point of shoulder

Scapula

Shoulder blade; flat triangular bone on posterior thorax

Thoracic vertebrae

12 vertebrae (T1-T12) of mid-back region that articulate with ribs

Inspiration

Active phase of ventilation; requires muscles and thorax to bring air into lungs

Expiration

Passive phase of ventilation; movement of air out of lungs

Alveolar PCO₂

40 mm Hg

Alveolar PO₂

100 mm Hg

Mixed venous blood PCO₂

45 mm Hg (in pulmonary artery)

Mixed venous blood PO₂

40 mm Hg (in pulmonary artery)

Oxygenated blood PCO₂

40 mm Hg (in pulmonary vein)

Oxygenated blood PO₂

100 mm Hg (in pulmonary vein)

Gas exchange mechanism

Gas movement occurs DOWN pressure gradients from high to low concentration via diffusion

Pulmonary artery blood

Brings mixed venous (deoxygenated) blood TO the alveolus

Pulmonary vein blood

Carries oxygenated blood AWAY from the alveolus

Scoliosis effect on respiration

Influences breathing patterns and causes air trapping

Obesity effect on respiration

Correlated with chronic bronchitis

Opioids effect on respiration

Alter rate and depth of breathing

Panic effect on respiration

Causes tachypnea (rapid breathing)

Older adult respiratory changes

Bony landmarks more prominent, kyphosis, barrel chest, tissues/airways more rigid, increased risk for pneumonia due to less effective airway clearance

Cough function

Cleansing mechanism to keep airway clear of secretions; can be dry or productive

Wheeze cause

Restricted airways

Sputum

Respiratory secretions

Dyspnea

Shortness of breath; subjective symptom

Four components of respiratory assessment

Inspection, palpation, percussion, auscultation

Signs of respiratory distress

Club nails, tripoding, nasal flaring, altered mental status, labored breathing, pursed-lip breathing, pallor, cyanosis, use of accessory muscles

Normal AP:transverse diameter ratio

1:2 (AP diameter should be half the length of transverse diameter)

Barrel chest ratio

1:1 (AP diameter equals transverse diameter)

Barrel chest causes

Commonly seen in emphysema (air trapping), normal in infants, can occur with aging due to osteoarthritic changes

Pectus excavatum

Chest wall deformity with sternal depression

Pectus carinatum

Chest wall deformity with sternal protrusion

Kyphosis

Spinal curvature affecting chest configuration

Normal respiratory rate

12-20 breaths/min, regular

Tachypnea

>24 breaths/min, shallow; caused by fever, anxiety, exercise, respiratory disorders

Bradypnea

Hyperventilation

Increased rate and depth; caused by extreme exercise, fear, or diabetic ketoacidosis (Kussmaul's respirations)

Hypoventilation

Decreased rate and depth, irregular; caused by overdose of narcotics or anesthetics

Cheyne-Stokes respirations

Alternating periods of deep, rapid breathing followed by periods of apnea; regular pattern; caused by drug overdose, heart failure, increased intracranial pressure, renal failure

Biot's respirations

Varying depth and rate of breathing followed by periods of apnea; irregular; caused by meningitis or severe brain damage

Apnea

Absent breathing

Palpation assessment

Assess skin temperature, masses, edema, tenderness, point of maximal impulse (PMI), extremity pulses and capillary refill

Percussion use

Not frequently used; generally done by advanced practice providers

Auscultation technique

Start on back, use diaphragm of stethoscope, start at top and move side to side in "Z" pattern, patient takes slow deep breaths in through nose and out through mouth, compare sides for asymmetry

Bronchial breath sounds

Heard over trachea; high-pitched; inspiration slightly shorter than expiration

Bronchovesicular breath sounds

Heard over main bronchi; medium pitch; inspiration equals expiration in length

Vesicular breath sounds

Heard over peripheral lung fields; low-pitched; inspiration longer than expiration

Abnormal bronchial sounds location

If heard at bases, it is abnormal; vesicular sounds become bronchial when fluid/mucus present in areas that normally have vesicular sounds

Crackles characteristics

High-pitched, discontinuous "popping" sound; usually heard during inspiration; typically does not clear with coughing

Crackles mechanism

Produced by air passing through fluid in small airways/alveoli and reopening of collapsed alveoli

Crackles causes

Inflammation or congestion; associated with pneumonia and congestive heart failure

Fine crackles

Brief sounds like hair rubbing together between fingers

Coarse crackles

Louder, moist bubbling sounds

Crackles intervention

Fluid restriction; diuretics

Wheeze characteristics

High-pitched, continuous, musical, squeaking; heard during inspiration or expiration

Wheeze mechanism

Produced as air passes through narrow airways constricted by swelling, narrowing, secretions, or tumors

Wheeze causes

Often heard in patients with asthma, tumors, or excess secretions

Wheeze intervention

Bronchodilators; hydration; coughing

Stridor characteristics

High-pitched crowing sound; can be heard on inspiration or expiration (typically inspiration)

Stridor causes

Associated with upper airway obstruction (larynx/trachea narrowing) and croup; common in infants/young children with croup

Rhonchi characteristics

Low-pitched, continuous, snoring or rumbling sound; usually heard during inspiration and expiration; may clear with coughing

Rhonchi mechanism

Usually caused by secretions in large bronchial airways; air bubbling past secretions; mucous produces loud gurgling sound throughout inspiration and expiration

Rhonchi description

"Junk in lungs"; louder than crackles

Rhonchi intervention

Cough and deep breathing; hydration; humidified air; mobilize patient

"Rhonchi in the bronchi, Rales in the tails" mnemonic

Rhonchi are heard in larger airways (bronchi); rales (crackles) are heard in smaller airways (tails/periphery)

Normal respiration requirements

Integrity of airway system for O2 transport, functioning alveolar system to oxygenate venous blood and remove CO2, functioning cardiovascular system to carry nutrients and waste

Renal/cardiac disorders effect on respiration

Compromised respiration due to fluid overload and impaired tissue perfusion

Muscle function alterations effect

Inadequate pulmonary ventilation/respiration