Disorders of the Chest Wall & Pleura

(week 5 pt.3)

• structural deformity

• trauma, pain, or immobilization

• excess chest wall weight

• neuromuscular weakness

common causes of chest wall restriction

the physiologic effects of chest wall restriction starts with ___ chest expansion → decreased ___ volume → decreased alveolar ventilation → ____. Secondary hypoxemia may develop. ___ cough effectiveness → ___ retention

decreased, tidal, hypercapnia, decreased, secretion

normal pleural mechanics include lung naturally ___ inward due to ___ fibers, and alveolar ___ tension

recoiling, elastic, surface

chest wall naturally recoils

outwards

pleural space in normal lungs are

sealed

with normal functioning lungs opposing ___ forces tend to pull the ___ surfaces apart

recoil, pleural

negative intrapleural pressure is desired because this ____ pressure keeps the ___ expanded with the chest ___

negative, lung, wall

pneumothorax

presence of air in the pleural space

pneumothorax occurs when ___ enters the ___ space. Normal pleural ___ relationship is disrupted. When the lung ___ inward → collapse → decreased ventilation to affected ____

air, pleural, pressure, recoils, alveoli

pneumothorax leads to ___ V/Q → impaired oxygenation → ___

low, hypoxemia

the degree of collapse with a pneumothorax depends on the amount of ___ in the pleural space

air

the two categories of pneumothorax include:

spontaneous and traumatic

the two types of spontaneous pneumothorax include

primary and secondary

Primary spontaneous pneumothorax

no known underlying lung disease; often associated w/ bleb rupture

secondary spontaneous pneumothorax

occurs w/ underlying lung disease

traumatic pneumothorax is the result of ___, Iatrogenic/procedural ____, or barotrauma from mechanical ____

trauma, injury, ventilation

barotrauma

sudden change in ambient pressure

open pneumothorax is when the ___ space communicates with the atmosphere, air can enter during inspiration and ___ during expiration, ___ lung collapse may occur

pleural, leave, partial

tension pneumothorax causes a ___-way valve effect, ___ enters but cannot escape, pleural pressure progressively ____

one, air, rises

tension pneumothorax can cause ___ compression and ____ shift

lung, mediastinal

with a tension pneumothorax ___ venous return → decreased ___ output → hypotension/shock

decreased, cardiac

pleural effusion

excess fluid in the pleural space

with pleural effusion as fluid accumulates: the adjacent lung ___, limiting ___ expansion, decreased ___ to affected alveoli → low V/Q (as perfusion may continue)

compresses, lung, ventilation

larger pleural effusions can lead to

hypoxemia

the main types of pleural effusion include

transudative and exudative

transudative pleural effusion

imbalance in hydrostatic or oncotic pressure, fluid moves from capillaries into pleural space

examples of transudative effusion include

heart failure and hypoproteinemia

exudative pleural effusion

inflammation/injury → increased capillary permeability, protein- and cell-rich fluid enters pleural space

examples of causes of exudative pleural effusion

infection, inflammation, malignancy

other pleural collections (pleural effusion causes)

empyema (pus), hemothorax (blood), chylothorax (lymph)