PHYT5114 - Cardiorespiratory HPRO I - Midterm

T/F Thoracic wall and thoracic cavity are interchangeable terms

False

What is the role of parietal pleura in the thoracic cavity

Outer layer; covers the mediastinum, inner thoracic cavity (Chest Wall) and diaphragm

What is the roll of the visceral pleura in the thoracic cavity

Inner layer; covers the external lung sufaces and lines fissures (inseparable from lung tissue)

What is the pleural space?

The potential space (small but with potential to expand) between the two pleura (visceral and parietal) of the lungs

T/F the parietal and visceral pleura directly contact one another

False

T/F, the lungs and thorax are mechanically independant during breathing due to attachment of the lungs to the thoracic wall via pleural membranes?

False, they are mechanically interdependant. The movement of one structure influences the others due to the surface tension of the pleural fluid in the pleural space connecting the two.

What is the role of pleural fluid

1. creates surface tensions that holds the peural layers together during ventilation

2. Reduces friction between the lungs and thoracic wall (lubricant)

T/F the lungs are identical in structure

False - The left has and upper and lower lobe separated by an oblique fisssure, while the right has these plus a middle lobe and horizontal fissure. The left also has a cardiac notch and lingula

What are the structural differences between the two the lungs

The right lung has three lobes where as the left lobe has two lobes

T/F the superior lobes of both lungs are the same

False, the left superior lobe has the cardiac notch wherein the heart sits. It also has a lingula at the level of the right middle lobe.

T/F boths lungs occupy the same volume

False, the left is smaller due to the cardiac notch

T/F the lingula is a vestigial lobe of the left upper lobe

True

T/F, accurate landmarking of the lungs and their lobes is essential for effective assessment and treatment

True

What is the Hilum

region or doorway on the medial surface of each lung where structures enter and exit. "port of entry"

What structures form the root of the lungs

bronchi, pulmonary artery, pulmonary veins, lymphatic nerves

What structure separates the two lungs

the mediastinum

Why is the left lung smaller

because the heart is situated on the left of the midline, and takes up some of the lung space

Why are bronchopulmonary segments important for lung function?

Each has a segmental bronchus, artery, vein and nerve supply. If one section is compromised, that segment can be surgically removed with minimal impact to surrounding lung tissue

What does the pulmonary artery carry

Deoxygenated blood to the lungs. This is the only artery (apart from placental arteries that does this)

What innervates the diaphragm, what spinal nerves form it?

Phrenic nerve, C3,4,5 keeps the diaphragm alive

T/f the phrenic nerve has mixed sensory and motor function

True

What are the divisions of the lower respiratory system

- Tracheobronchial tree (Conducting zone)

- Terminal respiratory units

What is included within the cunducting airways?

All airways down to terminal bronchioles

Do conducting airways participate in gas exchange?

No

Describe progression of airway diameter with each branching generation

Decreasing

Explain the air flow chart

Trachea > Primary bronchi > secondary bronchi > tertiary bronchi > Bronchioles > terminal bronchioles

What is the carina

The cough receptors, stimulates cough when agitated

Where does the trachea bifurcate

Level with the sternal notch

Differentiate between the right and left main bronchus

Left is more horizontal, narrower. Any bodies passing through the trachea will likely pass into the right bronchus. This increases risk of aspirational pneumonia in the right lung.

What is the role of cartilage in the respiratory tract

Provides structural support to the bronchi and prevent airway collapse

What is the purpose of cilia and goblet cells in the mucosiliary escalator

The goblet cells produce the protective mucus layer to trap foreign bodies, the cilia move mucus upward.

What prevents collapse of strutures from brochioles down

They are kep open by elastic lung tissue through radial traction which increases airway diameter during lung inflation

How many alveoli are there

Millions, the more there are, the greater the surface area, the greater the gas exchange

What is the role of the terminal respiratory units

Starting at the respiratory bronchioles, these airways are responsible for gas exchange.

T/f the surface of the alveoli matches exactly the need of the body

False - the are extremely over-built

What is lung parenchyma

All the lung tissue involved in gas exchange (Terminal respiratory units and the capillaries that surround them

Type I pneumocytes

Squamous epithelial cells that make up the extremely thin alveolar wall to allow rapid diffusion of gases

Type II pneumocytes

secrete surfactant, reducing surface tension and preventing alveolar collapse

Alveolar macrophage

patrol the alveolar surface to remove debris and pathogens

What is the ECM

Extracellular matrix, everything holding the lungs together, providing structural support and maintains lung shape, ensuring lung elasticity and recoil. Contains collagen for strength, elastin for elastic recoil.

Lung interstitium

Connective tissue framework between alveoli and capillaries. Includes ECM + fibroblasts and immune cells, blood vessels, and lymphatics

What is the difference between the lung parenchyma, lung interstitium, and lung extracellular matrix?

Lung Parenchyma

- Functional lung tissue for gas exchange

- Oxygen-CO₂ exchange

- Alveoli, bronchioles, capillaries

Lung Interstitium

- Supportive framework within parenchyma

- Structural support, fluid balance

- Fibroblasts, collagen, elastin, vessels

Lung Extracellular Matrix (ECM)

- Non-cellular structural network

- Mechanical strength, signaling

- Collagen, elastin, laminin, proteoglycans

What are the 3 major defence mechanisms against pollution, dust and foreign particles for the lungs

- Mucocilliary escalator (MCC)

- Effective cough

- Alveolar macrophages

Explain the MCC

Mucocilliary clearence: locates in the trachea, bronchi, and bronchioles, it removes harmful substances from the airways. Muscous traps foreign bodies, while cilia move the debris towards the mouth

How might the MCC be impared

1. damage to cilia (ex. smoking or disease)

2. Thickening of surface liquid

3. mucus dirupts clearance (damage to goblet cells)

What is the result of impaired MCC

Retained secretions

infection

inflammation

airway damage

Leads to airflow obstruction and reduced gas exchange (impaired lung function)

What happens to the mucus post MCC

Swallowed or expactorated (spit out)

Compare mucus, phlegm, and sputum

Mucus: produced by goblet cells

Phlegm/Sputum: mucus + saliva from lower airways

What features of sputum are we looking at in qualitative assessment

colour

consistency

volume

presence of blood (Hemoptysis)

purulence (indication of puss or infection)

What is hemoptysis

Blood in sputum

Why do we care about checking sputum

Quick insight into current and ongoing changes to respiratory status

What are excess secretions? Give examples

Anything being expactorated (Ex. edema fluid, pus, blood, inflammatory exudate)

Define Secretion

any material produced within or entering the airways that can accumulate and affect ventilation

Why does understanding of secretions in sputum matter?

The type of secretion gives clues about underlying causes

An effective cough clears secretions down to where in teh airways?

6th-7th generation

T/f bronchioles, terminal bronchioles, respiratory bronchioles can be cleared by cough

False

What is ACT

Airway Clearing Techniques

What are the three phases of a cough

1. inspiratory phase - deep breath in

2. compresssive phase - glottis closes, pressure builds

3. expiratory phase - glottis opens, forceful air expels secretions

T/f when assessing cough, we only consider the function of the expiratory phase

False, you sould check effectiveness of all three phases

What is an effective cough?

A strong, coordinated action involving the three phases that clears secretions and protects airways, supporting the MCC and maintaining lung health

How do PTs assess cough effectiveness

- observe depth of inspiration, strength and duration of cough, and ability to expactorate sputum = qualitative assessment

- measure cough peak flow (CPF) to quantify cough strength

What are key terms for documenting cough qualitatively

- spontaneuous/protective

- directed/voluntary

- effective/ineffective/absent

- productive

- non-productive (dry)

- Acute vs. chronic

- Hemoptysis

What does the acronym SOAP mean

Subjective

Objective

Assessment

Plan

What is meant by spontaneous/protective cough?

Occurs reflexively

What is meant by directed/voluntary cough?

initiated on command

What is meant by effective/ineffective/absent cough?

notes strength and clearance, does it move secretions?

What are questions to ask to identify why a cough is ineffective

- Is pain a limniting factor?

- weak inspiratory effort?

- weak expiratory effort?

What is meant by productive cough?

produces sputum (document colour, volume, consistency)

What is meant by non-productive cough?

Dry - no sputum

What is meant by acute cough?

ongoing for less than 3 weeks

What is meant by chronic cough?

ongoing for more than 8 weeks

What is responsible for clearing particles from the surface of the alveoli

alveolar macrophages (MCC does not extend to the alveoli; cough can't clear here)

Why might cigarette smoke, alcohol, oxidant gas, alveolar hypoxia, radiation, or immune suppressant drugs increase risk of infection/inflammation?

they impare alveolar macrophage activity

Compare ventilation and respiration

Ventilation: the movement of air through the air ways

Respiration: exchange of gases at the alveoli

Effective ventilation requires what?

Movement of the thoracic cage and diaphragm

As thoracic volume increases, how does pressure change

It decreases

T/F internal intercostals are a main inspiry muscle

False - the external intercostals

What are accessory muscles of inspiriation

scalenes, SCM

What is the primary inspiry muscle

Diaphragm

What spinal nerves make up the phrenic nerve

C3,4,5 keep the diaphragm alive

Diaphragm contracts and thoracic volume...

Increases in all directions

Name 6 factors that can affect diaphragm excursion

- weakness

- body position

- stomach fullness

- obesity

- pregnancy

- fluid in the abdomen

Why does the right hemidiaphragm sit 1-2 cm higher than the left?

The liver sits inferior to it

How do external intercostals aid in ventilation

Elevate rib cage and expand chest volume

Explain pump-handle movement

- ribs elevate (front)

- increases anterior-posterior (AP) diameter of the chest

- maintly involves upper ribs (1-6)

Explain bucket handle movement

- Ribs elevate laterally

- increases lateral diameter of the chest

- mainly involves lower ribs (7-10)

Pump- or Bucket-handle, which has the greatest effect on inspiratory volume

Bucket Handle

What are some examples of when rib mechanics might be altered

- COPD (barrel chested: inability to lift ribs further)

- post-thoracic surgery or trauma (pain and scaring limit expansion)

- neuromuscular diseases (weak respiratory muscles)

- scoliosis and chest wall deformities (structural changes to normal rib movements and lung expansion

- prolonged immobilization or ICU stays (decreased mobility leads to stiff rib cage and impaired breathing

How do scalenes and SCM help with ventilation

Scalenes: lift the first two ribs

SCM: lifts sternum (aids in pump handle)

When would you see accessory respiratory muscle use

- exercise

- respiratory distress

- diaphragm weakness

- obstructed airways (increased WoB)

How to tell when accessory muscles are used

- neck muscles visibly contracting

- shoulder elevation

- laboured or noisy breaths

- nasal flaring

T/F PTs can diagnose respiratory distress

False, it is a clinical sign that patient is working harder to breathe, not a diagnosis

What are signs of respiratory distress in infants/children

- head bobbing (strong SCM)

- nasal flaring

- grunting

What are signs of respiratory distress

- tachypnea

- increased HR

- intercostal indrawing

- paradoxical breathing

- accessory muscle use

- tripod position

- pursed lip breathing

- diaphoresis (sweating)

- cyanosis

What is the benefit of the tripod position

allows for greater contribution from accessory muscles

Compare sign vs. symptom

Sign: objective finding (what you measure, i.e. accessory muscle use, RR^, cyanosis)

Symptom: subjective experience (what patient reposrts, i.e shortness of breath, chest fatigue)

What is the zone of apposition (ZoA)

The region where the muscle fibers of the diaphragm is in direct contact (apposed) with the the inner surface of the lower ribs

Concerning how the Zone of Apposition (ZoA) supports ventilation, explain the thoracic and abdominal interaction

As the vertical thoracic volume increases, intra-abdominal pressure increases, causing the abdomen to expand outward

Explain zone of apposition activation

Abdominal contents push back against the lower ribcage, causing the ribcage to push up and out from inside (bucket handle motion)

Why would weak muscles in the abdomen lead to limited zone of apposition activation

If the muscles of the abdomen are weak they will allow the abdomen to deform under the pressure from the increasing thoracic volume, and will therefore not be able to build the abdominal pressure required to push back against the ribs to facilitate the bucket handle motion