Chapter Six - Conditions Affecting the Pleural Space

Question 1

Why is it important to know about the conditions affecting the pleural space?

Answer 1

Knowing about the pleural space, we can be able to recognise what a condition that affects the pleural space looks like, and decide what to do about it

Question 2

What happens when the rib cage expands to the pleural pressure? What is the pleural space called, in health, and where is it situated?

Answer 2

Pressure in the pleural space is negative, but when the rib cage expands, the pressure becomes even more negative. If the pressure were to become positive, the lungs couldn’t expand

In Health:

Pleural space is a “virtual space”

Parietal and Visceral Pleura touch and are lubricated by a small amount of fluid

Question 3

Is the fluid in the pleural space stagnant? Explain

Answer 3

Lymphatics drain the pleural space, there is a circulation of fluid through the pleural space. Fluid flows in from the arteries, then is drained in small amounts in the veins, but mostly in the lymphatics

Question 4

What does fluid in the pleural space (pleural effusion) look like in an x-ray?

Answer 4

What fluid in the pleural space might look like in a chest x-ray. Fluid is increasing the density, and so it looks whiter

Question 5

Where are the capillaries situated in the pleura?

Answer 5

General slide, we don’t need to know this level of detail: just notice what we already talked about: capillaries in the visceral and parietal pleura, with fluid moving into the pleural space, and then drained by the lymphatics.

Question 6

Give and describe the Starling Equation (about capillary fluid exchange).

Answer 6

If pressure increases in the vessel, fluid will come out of the vessel

There should not be any protein in the interstitial fluid, in health

Hydrostatic pressure: more blood volume in the capillaries, which creates a force for the liquid to come out of the vessel, proteins suck fluid in the vessel, so the net driving force is to keep fluid in the vessel. Reflexion coefficient (tightness of the vessel wall): the blood vessel has a tight wall, if the blood vessel wall becomes more permeable (ex: inflammation), then it would be easier for blood protein to move out of the capillary in the interstitial space and draw more fluid (plasma) there with them.

(pi)c: Formed primarily by blood proteins

NDF: Net Driving Force: which way the liquid is going, in the capillaries

Question 7

Give the common causes of pleural effusion (mechanism and clinical examples). What is the peritoneum?

Answer 7

Peritoneum: covers your abdomen. A lot of fluid in it = pressure that can push through the diaphragm and into the pleural space. Blood can move into the pleural space = not good.

Question 8

What is empyema? Is it treatable?

Answer 8

Empyema is a collection of pus in the pleural cavity. It is usually associated with pneumonia but may also develop after thoracic surgery or thoracic trauma.

It is treatable.

Question 9

How does pleural effusion affect lung function?

Answer 9

It depends on the size: bigger pleural effusion = bigger effect on the lung (Size-dependent: Lung compression and CW expansion)

Lung volume is less than in a healthy lung because it is being compressed into a smaller space

Could lead to atelectasis, and a chest wall expansion to try to decrease the negative effect of the pleural effusion

Question 10

Management of Pleural Effusions: what treatment would a competent PT provide?

Answer 10

Patient repositioning, we would put the patient lying on the unaffected side (more air coming in)

Deep breathing has absolutely no lasting effect if you do nothing about the effusion

Question 11

How does chest tube work and what does it do? What else could help with pleural effusion drainage?

Answer 11

Muscle contractions could POSSIBLY help the lymphatic system (with the one-way valve system)

Chest tubes help the lymphatic system by draining the excess liquid in the pleural space

The lung can react very quickly to the drainage, it depends how long it has been there

Bottle below the level of the lung: gravity drainage. If you lift the bottle above the lung, the fluid will be flowing back into the lung. For sure on OSCEs…

Question 12

Draw the chest tube drainage system.

Answer 12

(see other picture in the notes)

Question 13

What does air in the pleural space do?

Answer 13

Puts a big pressure on the lung, and it collapses under the pressure

Question 14

Name the three types of pneumothorax and tell what they are.

Answer 14

Closed
 Rupture of lung, and visceral pleura. During surgery: frequently there is a chest tube

Tension

 Medical emergency

 Increasing air in pleural cavity displacing mediastinum and compressing opposite lung

Open
 Penetrating wound. There is something penetrating the chest wall (ex: stab wounds)

Question 15

What is the difference between an open and a closed pneumothorax?

Answer 15

Closed: No opening in the chest wall

Young tall skinny males: they have blebs (weak spot on the wall of the pleura)

Question 16

What is a possible complication of a tension pneumothorax?

Answer 16

Mediastinal Shift -> Life Threatening!

Typically air can get into the pleural space but it can’t get out

When we breathe out, the positive pressure covers that whole (flap, fluid…), so the air builds up in the pleural cavity and everything gets pushed aside

Compresses aorta: less blood comes out of the heart

Question 17

What is a subcutaneous emphysema?

Answer 17

Pressure in the pleural space, air could get out of the lungs. Extra air in the subcutaneous tissues

Subcutaneous emphysema MAY be a symptom of a hemothorax. It may mean that they’re developing a slow tension hemothorax

Question 18

What happens when a chest tube drainage is going well (doing its job)?

Answer 18

Question 19

Describe the components of the clinical reasoning framework. What is adventitia?

Answer 19

Clinical Reasoning Framework

Assessment Finding (they need to be things that we can do something about) Ex: Crackles in the RML

Impairment Ex: Atelectasis in the RML
Cause Ex: Pain
Activity Limitation (not much info, but probably they are not taking a deep breath in (chest wall expansion = not great))

Participation Limitation

Problem Statement

Treatment Plan ex: Control the pain, encourage effort for deep breathing, and chest wall expansion

*You take your assessment findings, and they tell us what the impairment is. The assessment findings might be something like absent breath sounds, the impairment might be atelectasis. Then we need to think about the cause. We want to think about the activity limitations and weather that has any participation level limitations. We are always thinking about the discharge goals, those are the meaningful things to the patient. Problem statement pulls all those things together, ex: atelectasis in the LLL due to poor inspiratory effort because of pain. When you’ve done that, the treatment is easy: you have to get the person to breathe and get better.

*Adventitia: always abnormal breath sounds, that should never be there

*** Remember: the most obvious thing is not always your biggest problem