Chapter 25: assessment of the respiratory system

Question 1

Primary purpose of respiratory system

Answer 1

Gas exchange: transfer of O2 and CO2 bt atmosphere and blood

Question 2

Upper respiratory tract

Answer 2

nose, mouth, pharynx, epiglottis, larynx, trachea

Question 3

Turbinates

Answer 3

increase surface area of nasal mucosa which warms and moistens air as it enters the nose

Question 4

Larynx

Answer 4

covered by epiglottis during swallowing
houses vocal cords

Question 5

Trachea
-Carina

Answer 5

10-12 cm long
covered with U-shaped cartilage to allow swallowing
bifurcates at carina at angle of Louis at 4th and 5th vertebrae
Carina is super sensitive –> stimulation of it triggers intense coughing

Question 6

Lower Respiratory tract

Answer 6

Bronchi
Bronchioles
Alveolar ducts
Alveoli

Question 7

Lungs
-where is aspiration more likely to happen?

Answer 7

R = 3 lobes
L = 2 lobes
Mainstem bronchi, pulmonary vessels, and nerves enter at hilus

Right bc mainstem bronchi is straighter, shorter, and wider

Question 8

Functional roles of each part of the lower airways

Answer 8

Trachea and bronchi = anatomic dead space (VD); no gas exchange

Bronchioles = smooth muscle constricts and dilates

Alveoli = terminal part of respiratory tract; gas exchange

Question 9

Tidal volume and what part of that is dead space?

Answer 9

Tidal volume is about 500 mL
Of that, 150 mL is dead space

Question 10

Alveoli: structure and function

Answer 10

main site of gas exchange with pulmonary capillaries
300 mil- each .3mm across
Connected by pores of Kohn –> let air pass, but also bacteria
Volume of 2500 mL
Surface area of a tennis court

Question 11

Surfactant

Answer 11

lipoprotein secreted by alveoli when stretched
-reduces surface tension, making alveoli less likely to collapse

People take slightly larger breath (sigh) every 5-6 breaths to promote surfactant secretion

Question 12

Atelectasis

Answer 12

collapsed alveoli
Big risk for post-op because anesthesia, decreased mobility, and pain alter breathing

In ARDS, lack of surfactant causes widespread atelectasis and collapse of lung tissue

Question 13

Blood supply: Pulmonary circulation and Bronchial circulation

Answer 13

Pulmonary
-pulmonary artery brings deoxygenated blood to lungs from R ventricle
-gas exchange happens in capillaries
-pulmonary vein brings oxygenated blood to left atrium

Bronchial
-bronchial arteries branch off of thoracic aorta
-azygos vein brings deoxygenated blood to superior vena cava

Question 14

Chest wall components

Answer 14

Thoracic cage
-12 pairs of ribs and sternum –> protect lungs and heart

Mediastinum
-space in middle of thoracic cavity
-houses heart, aorta, and esophagus
-separates R and L lungs into 2 separate compartments

Pleura
-visceral has no pain fibers/nerve endings, but parietal does –> that’s why inflammation can cause pain with breathing
-intrapleural space –> 20-25 mL fluid to lubricate during breathing and promote expansion of lungs during inspiration

Diaphragm
-major muscle of respiration
-innervated by R and L phrenic nerves from cervical vertebrae 3-5
-each side innervates one half (hemidiaphragm)
-damage above C3 paralyses entire diaphragm

Question 15

Issues with intrapleural space

Answer 15

-usually fluid drains via lymphatic circulation

Pleural effuision = accumulation of fluid here
-can happen bc blockage of lymphatic drainage from cancer
-can happen bc of hear failure, causing imbalance bt intervascular and oncotic fluid pressure

Emphysema
-purulant pleural fluid with bacterial infection

Question 16

Muscles during inspiration

Answer 16

Diaphragm: contracts and moves down
Internal intercostals: relax
External intercostals: contract
scalene: contract to raise ribs 1 and 2

Question 17

Oxygenation
-normal partial pressure
-normal arterial saturation

Answer 17

Oxygenation = O2 from atmosphere to organs and tissues
-oxygen dissolved in plasma = partial pressure of oxygen in arterial blood (80-100)
-Oxygen bound to hemoglobin = arterial oxygen saturation (SaO2) –> (>95%)

O2 and CO2 move via diffusion until equilibrium is reached

Question 18

Ventilation

Answer 18

-inspiration and expiration due to intrathoracic pressure changes and muscle action
-gas flows from higher pressure to lower pressure

Inspiration takes effort- expiration is passive
-elastic recoil = lungs bounce back after being stretched –> elastin in alveolar walls and around bronchioles

Question 19

Ventilation issues

Answer 19

Dyspnea
-mandates that accessory muscles help expand thorax

Shallow breaths
-caused by phrenic nerve paralysis, rib fractures, neuromuscular issues
-lungs don’t fully inflate and gas exchange is impaired

Active expiration
-caused by exacerbations of asthma or COPD
-abs, intercostals, scalenes, and trapezius engaged

Question 20

Compliance and Resistance

Answer 20

Compliance
-ease of lung expansion –> elasticity of lungs and elastic recoil of chest wall
-Decrease = hard to inflate; Increase = hard to recoil
-Decrease caused by fluid (pulmonary edema, ARDS, pneumonia); less lung elasticity (pulmonary fibrosis, sarcoidosis); or restriction of lung movement (pleural effusion)
-Increase caused by destruction of alveolar walls and less tissue elasticit (COPD)

Resistance
-airflow impeded during inspiration and/or expiration –> altered airway diameter
-asthma causes bronchoconstriction
-secretions are also an issue

Question 21

Respiratory center

Answer 21

Medulla in brainstem
responds to chem and mech signals
sends impulses from spinal cord and phrenic nerve to respiratory muscles

Question 22

Central Chemoreceptors

Answer 22

responds to changes in PaCO2 and pH in surrounding fluid

Central chemoreceptors in medulla
-increase H+ concentration = acidosis –> results in increased RR and VT (tidal v)
-decrease H = alkalosis –> decreased RR and VT
Increased PaCO2 = increased H2CO3 = decreased pH of CSF –> increased RR
Decreased Pa CO2 = decreased H2CO3 = increase pH of CSF –> decrease RR

Question 23

Peripheral chemoreceptors

Answer 23

in carotid bodies and aortic bodies
-respond to decreased PaO2, decreased pH, and increased PaCO2
-stimulates respiratory center to increase RR

COPD - chronically increased PaCO2 –> desensitizes person to further increases
-maintain ventilation from hypoxic drive
-healthy person’s PaCO2 doesnt vary more than 3 mm Hg

Question 24

Mechanical receptors

Answer 24

in conducting upper airway, chest walls, diaphragm, and alveolar capillaries

Stimulated by:
-irritants (conducting airway) –> stimulates cough
-stretch (smooth muscle) –> Hering Breuer reflex stops overdistension of lungs
-J receptors (alveolar capillaries) –> sense high pulmonary capillary pressure causing rapid shallow respiration seen in pulmonary edema

Question 25

Respiratory Defense Mechanisms

Answer 25

Filtration of air -- nasal hairs and shape of passage -- 1um things get to alveoli Mucociliary clearance -- ciliary action fucked up by dehydration, smoking, too much O2, infection, alcohol, drugs (including anesthetics) -COPD and cystic fibrosis are associated with destroyed cilia Cough reflex -- mucociliary clearance backup --> only effective for large or main airways Reflex bronchoconstriction - response to inhaling a lot of irritants (also asthma) Alveolar macrophages - bc there's no cilia below resp. bronchioles --> bring stuff to cilia or lymph system --> can't eat coal dust or silica --> damaged by smoking

Question 26

Gerontologic changes in respiratory system

Answer 26

Structural changes -calcification of costal cartilage = low chest expansion -kyphosis (esp osteoporosis) leading to barrel chestedness + accessory muscle use -resp. muscle strength declines, so lungs are harder to inflate -less alveoli and less elastic -lower airways close earlier, so gas exchange mostly happens in top part of lungs --> low PaO2 Defense mechanisms -decrease in immunity -macrophages start to suck; coughs are weaker; less functional cilia; drier membranes; less IgA; less feeling in pharynx = aspiration Respiratory control -more gradual response to O2 and CO2 levels -smoking, obesity, and chronic illness put you at more risk of this

Question 27

What to do during an assessment if respiratory distress is severe?

Answer 27

only get important info --> postpone the rest til condition has stabilized

Question 28

Assessment: Health history

Answer 28

Upper: colds, sore throat, sinus infection Lower: asthma, COPD, pneumonia, TB Allergies: triggers, manifestations, and frequency dyspnea could mean heart failure frequent resp infections could mean HIV

Question 29

Assessment: medications and surgeries

Answer 29

OTC, prescription, illicit, O2 *cough is common side effect of ACE inhibitors ask about intubation, nebulizer, humidifier, airway clearance modality...

Question 30

Functional assessment: health perception -coughs -sputum -wheezes -smoking -vaccinations -travel -equipment

Answer 30

-perceived change in respiratory health (COPD changes might be too slow to notice) -patient may relate change in symptoms rather than onset -quality of cough: loose=secretions; hacking = irritation/obstruc.; bark = upper airway obstruction from subglottic edema --> chronic if over 3 weeks sputum -clear usually; gray with flecks in smokers; whitish yellow in COPD -thick = dehydration; thin = post nasal drip or sinus drainage; pink and frothy = pulmonary edema -hemoptysis = pneumonia, TB, lung cancer, and severe bronchiectasis wheezes = obstruction -> asthma, aspiration, emphysema --> check for mycobacterium tuberculosis history too smoking -main risk for COPD -pack years = packs per day times years smoked vaccination -flu and pneumonia Travel -TB risk in developing countries -fungal lung infection risk if exposed to nature shit or immunocompromised ppl Equipment -make them show you how to use the inhaler

Question 31

Genetic risks for respiratory stuff

Answer 31

cystic fibrosis COPD asthma

Question 32

Functional assessment: nutrition

Answer 32

weight loss is symptom of resp disease -anorexia, weight loss, and malnutrition = COPD, lung cancer, TB, bronchiectasis -all metabolic demand is going to breathing Dehydration or fluid retention can affect mucus and gas exchange

Question 33

Functional assessment: elimination

Answer 33

-activity intollerance from dyspnea could lead to incontinence -limited mobility from dyspnea could lead to constipation -cough = stress incontinence

Question 34

functional assessment: activity and excercise

Answer 34

-determine extent to which dypnea limits excersise and ADLS -which positions make it better? Immobility can lead to pneumonia

Question 35

functional assessment: sleep-rest

Answer 35

asthma and COPD wake up with chest tightness/wheezing -- need med change heart probs = sleep sitting up to avoid orthopnea sleep apnea in obese ppl = snoring, insomnia, waking abruptly Night sweats = TB

Question 36

functional assessment: cognitive-perceptual pattern

Answer 36

Hypoxia = restlessness, irritability, memory changes -also inability to retain info, so can't follow treatment instructions Pain = pleurisy, fractured rib, costochondritis

Question 37

functional assessment: self perception/concept

Answer 37

body image issues or embarrasment from equipment needed to tend to repiratory issues -refer patient to support group

Question 38

functional assessment: role/relationship

Answer 38

-assess degree to which resp issues or treatments interfere with work -determine work/hobby exposure to irritants: coal, asbestos, silica

Question 39

functional assessment: sexuality

Answer 39

-changes in activity -positions that make it easier -equipment needed to engage in it

Question 40

functional assessment: coping/stress tolerance

Answer 40

dyspnea and anxiety exacerbate each other -determine coping strategies and suggest support gp

Question 41

functional assessment: value-belief

Answer 41

-determine level of adherence to plan -in noncompliant, determine why (cultural reasons?) -educate on benefits of treatment

Question 42

Physical assessment: nose -poly -discharge

Answer 42

patency, inflammation, deformity, symmetry, discharge polyp = allergies purulent + malodorant discharge = foreign body watery discharge = allergies or CSF bloody discharge = trauma or dryness thick discharge = infection

Question 43

physical assessment: mouth and pharynx

Answer 43

color, lesions, masses, gums, dentition, bleeding have them yawn if hard to see pharynx stimulate gag reflex for nerves IX and X

Question 44

Physical assessment: neck

Answer 44

symmetry, tenderness, swollen nodes tender, hard, or fixed nodes = disease

Question 45

Physical assessment: thorax and lungs

Answer 45

-do posterior chest first bc it gives the most info --> esp with females -have patient lean forward with arms crossed anterior chest- have patient sit up or semi-fowlers (30 degree)

Question 46

Physical examination: inspection of thorax

Answer 46

appearance, position, evidence of respiratory distress shape, symmetry, movement --> AP is 1/2 of T respiratory rate, depth, and rhythm --> inspiration should be 1/2 as long as exprtn -Cheyne-Stokes = rapid breathing with apnea breaks -Biots = irregular breathing with apnea every 4-5 cycles clubbing (over 180) = hypoxia --> usually nails get thicker and spongier cyanosis = hypoxia or low cardiac output

Question 47

Physical assessment: thorax palpation -tracheal deviation -chest expansion -fremitus

Answer 47

Tracheal deviation -away from tension pneumothorax or neck mass -towards pneumonectomy or lobar atelectasis Chest expansion -hands at costal margin (ant) or 10th rib (post) with thumbs at midline -thumbs should move 1" away from each other upon deep breathing -absent or unequal expansion = atelectasis, pneumothorax, or pleural effusion -decreased expansion = hyperinflation, barrel chest, or neuromuscular issues Fremitus -palms on back/chest while repeating phrase --> vibrations should be equal -stongest at sternum and bt scapulae -increase = fluid in the lungs or density or above pleural effusions -decrease = hyperinflation or pleural effusion -absent = pneumothorax or atelectasis -back is easier than chest

Question 48

Physical assessment: thorax Percussion

Answer 48

-in the intercostal spaces -ant should be resonant over lung tissues except where heart or liver makes it dull -post should be resonant until you get below diaphragm (flat)

Question 49

Physical assessment: auscultation -normal breath sounds -adventitious breath sounds

Answer 49

-apex to base unless they're in resp. distress or tire easily --> then do it backwards -honestly, just look at diagram to figure out where to listen Bronchial -loud, high, hollow --> I/E ratio of 2:3 with gap bt --> trachea Bronchovesicular - med pitch and volume --> 1:1 ratio --> ant bt 1st and 2nd; post bt scapulae Vesicular -soft, low, rustles --> 3:1 --> all over lungs except major bronchi Adventitous = wheezes, stridor, crackles, friction rub -stridor is obstruction in upper airway; wheezes is lower

Question 50

abnormal voice sounds

Answer 50

egophony = E sounds like A bronchophony = spoken stuff sounds normal whispered pectoriloquy = whispered stuff sounds normal

Question 51

diagnostic studies in general

Answer 51

-Pulse oximetry and ABG -If heart is working PaO2 or SaO2 will tell level of oxygenation --> can also assess CO2 for ventilation status -If bad heart or hemodynamic instability (low conciousness, irreg HR, low BP), might have inadequate tissue O2 or abnormal O2 consumption --> have to evaluate mixed venous blood gas

Question 52

Diagnostic studies: Oximetry

Answer 52

Pulse oximetry measures O2 saturation of hemoglobin --> 94-99% -common inpatient, excersise testing, adjusting O2 flow rate, and perioperatively (bc anesthesia) If under 70%, displays 4+- actual value Innaccurate if other stuff is bound to hemoglobin Other alterations = motion, low perfusion, anemia, cold extremeties, bright flourescent lights, intravascular dyes, thick acrylic nails, and dark skin

Question 53

Diagnostic studies: ABGs

Answer 53

-blood test that measures oxygenation and acid-base balance -PaO2, PaCO2, pH, HCO3, SaO2 PaO2 decreases with age and elevation No changes to O2 15 mins b4 sample; use heparin syringe; apply pressure for 5 mins after

Question 54

Diagnostic study: CO2 monitoring

Answer 54

Transcutaneous (PtCO2) or end tidal (PetCO2) capnography PtCO2 = arterial pressure of CO2 PetCO2 = alveolar CO2 during exhalationg (peak) -infrared light attached to tube -if no tube, nasal cannula and capnometer

Question 55

Diagnostic studies: mixed venous blood gases

Answer 55

Blood from pulmonary artery using catheter (one time) or fiberoptic sensor on central line (continuous) -normal SvO2 is 60-80% and PvO ~40 -early sign of change in cardiac output or O2 delivery CO2 a little higher; pH a little lower

Question 56

Diagnostic studies: sputum studies

Answer 56

collected via expectoration, tracheal suction, or bronchoscopy -can use sputum induction with irritating aerosol Acid fast; culture/sensitivity; cytology; gram stain to determine microbe

Question 57

Diagnostic study: skin tests

Answer 57

test for allergic reaction or exposure to TB bacilli or fungi TB positive = exposure to antigen (doesn't necessarily have TB) TB neg = no exposure OR depression of cell mediated immunity (HIV) 5mm if HIV, contact with TB, immunosuppressed 10 mm if immigrant from certain places, druggie, lab worker, diabetes, kidney stuff 15 mm anyone

Question 58

Diagnostic Studies: Bronchoscopy -Bronchoalveolar lavage

Answer 58

bronchi are seen through fiberoptic tube -obtain specimen -remove stuff -laser therapy, electrocautery, cryotherapy, and stents for patency Can be outpatient --> patient can be supine to sitting anethetize throat -can do through endotracheal tube CAUTION: verify consent; NPO; sedated -After: NPO til gag returns --> monitor for hemorrhage or pneumothorax BAL = sterile saline injected thru scope and withdrawn to examine cells

Question 59

Diagnostic studies: lung biopsy

Answer 59

Can do it : transbronchially, (foreceps or needle thru bronchoscope) percutaneously/ via transthoracic needle aspiration, (through chest w/ CT or US) -xray after to make sure no pneumothorax by video assisted thoracic surgery -rigid scope with lens goes through trocar into pleura via 1-2 incisions in thoracic cavity -view inside via the scope and take the sample -chest tube kept in place til lung expands -safer than open open lung biopsy -open chest with thoracotomy incision CAUTION -monitor distress, pneumothorax, bleeding, incision/chest tube care, breath sounds --> encourage deep breathing

Question 60

Diagnostic study: thoracentesis

Answer 60

large bore needle thru chest wall into pleural space to get specimen, remove fluid, or give meds patient is upright might leave in percutaneous catheter to drain fluid

Question 61

Diagnostic studies: pulmonary function test

Answer 61

measure lung volumes and airflow -diagnose/monitor disease; evaluate treatment; determine disability spirometer and computer calculate values --> coaching to do deep inhale and fast, forceful, FULL exhale --> normal is 80-120% of predictions if increase of 200 mL, positive bronchodilator response Used by ppl with asthma, COPD, cystic fibrosis, lung transplants, and thoracic surgeries

Question 62

Diagnostic studies: radiology

Answer 62

No metal --> check pregnancy chest xray = common CT --> check contrast/iodine allergy, renal func, hydration --> bad if warm/flushed MRI --> no metal, check implants, address claustrophobia (sedation) Ventilation-perfusion (V/Q) scan Pulmonary angiogram -> contrast precautions; pressure dressing to injection site; monitor distal circulation Positron emission tomography (PET) --> NPO prior; monitor glucose; FLUIDS