Flashcards in 11.30: Pleural Disease Deck (56)
Normal volume / function of pleural fluid?
- Lung's elastic recoil makes them want to collapse
- Ribs have the desire to expand
- This tugging pulls fluid into pleural space
Which pleura is innervated?
- Only the parietal, the visceral is not
- Important when draining fluid, ptn cannot feel if you poke lung if you hit visceral pleura
Blood supply to visceral pleura?
Arterial: bronchial and pulm arteries
Venous: through pulmonary veins to LA
Blood supply to parietal pleura?
Arterial: intercostals off aorta
Venous: through IVC to RA
What happens in primary left heart failure?
- Extra fluid left in LV at end of diastole increase EDP
- Pressure transferred back into pulm veins to alveoli leading to pulm edema AND movement of fluid into pleural space
- Typically effusion is larger on the right
What happens in pulm htn?
- Pleural effusion should not occur
- Back up is before blood gets to interstitium so blood should back up into IVC/SVC
- Leads to Cor pulmonale
***Pulm htn. can made left sided effusion worse since parietal pleura drains to IVC
Normal pressure in pleural space?
- Negative 5 due to competing recoils of lungs and ribs
What can cause pleural fluid formation?
1. Leaky pleura: inflammation
2. Changes in hydrostatic or oncotic pressure
Definition of pleural effusion?
- Extra fluid in the pleural space
Symptoms of pleural effusion?
2. Pain: more likely if small as pain is from surfaces rubbing together, large effusion pushes them apart
4. Respiratory failure
Exam findings in pleural effusion?
1. Dullness to percussion: when tapping in chest
2. Decreased breath sounds
3. Decreased tactile fremitus
4. Egophony- > E - A change
****Always need to be verified with cxr
Signs of pleural effusion on cxr?
1. Blunting of angle (costo phrenic angle of diaphragm)
2. Meniscus sign at top
3. White out
What can cause white out?
1. Massive pleural effusion
2. Atelectasis: lung has lost all its air
**During effusion trache will be pushed a bit away from fluid moving it
- Will be pulled to opposite side in atelectasis
Different between "White out" from massive effusion and atelectasis?
Effusion: trachea is being pushed AWAY from white out by fluid
Atelectasis: Trachea is being pulled TOWARDS white out
How to tell if white on xray is from fluid?
- Have ptn take x ray in lateral decubitus
- Fluid should FLOW towards side of ptn on the table
What are loculations?
- Fluid should NORMALLY flow to diaphragm if free flowing due to gravity
- Loculations or adhesions between pleura TRAP fluid from draining with gravity
****Usually this is caused by inflammation which is hard to treat with antibiotics, surgical procedure could be needed to drain
- Might be harder to hit with needle and pockets pay be different
What is thoracentesis?
- Numb skin and place needle OVER ribs to drain fluid
- Can be done to diagnose or treat
Why is it important to go OVER rib in thoracentesis?
- Neurovascular bundle runs under the rib
- Important not to hit these arteries / nerves
What can lead to leaky pleural place?
What can lead to increase pulm capillary pressure?
1. LV failure
What can lead to decreased pleural pressure?
What can lead decreases plump cap oncotic pressure?
Diagnostic categories of pleural effusion?
1. Leaky pleural space
2. Increase pulm cap pressure
3. Decreased pleural pressure
4. Decreased cap oncotic pressure
5. Direct entry of ascitic, blood, lymph, or gastric fluid
What is transudate?
- Nothing wrong with pleural space itself, there is just pressure gradient change
What is exudate?
- Leaky pleura
How is it determined if fluid is transudate or exudate?
- Thoracentesis with lab analysis
What is light's criteria?
Any 1 of these 3 criteria makes fluid exudate:
1. Pleural protein / serum protein > .5
2. LDH pleural / serum > .6
3. LDH pleural > 200
a. Cholesterol pleural > 45
***Can be issue since you need serum value for 2
Should Heart failure have transudate or exudate?
How could heart failure lead to false positive of serum exudate?
- Diuretics given to train off fluid
- Can falsely [protein/LDH] pleural fluid making it appear exudate
***Cholesterol will not be falsely elevated
DDx for transudate?
3. Nephrotic Syndrome
DDx for exudate?
3. Parapneumonic effusions
4. Pulm embolism
5. Connective tissue disease: lupus, ra
What is empyema?
- Infection in pleural space
- Cannot be treated by antibiotics alone as they only make it to pleural space
What are parapneumonic effusions?
- Infection in LUNG leading to inflammation of pleura
- Infection is in lung so easier to treat than empyema
Which pleural effusions are more worrisome?
Those with exudate
Other test performed on thoracentesis?
1. PH: if low, infection?
2. Glucose: worrisome if low
3. Cell counts: worrisome if puss
4. Hematocrit: if pleura > 1/2 serum = hemothorax
5. Cytology: tests for cancer
Categories of exudates?
a. Low PH / Glucose
b. High LDH
***Risk of empyema
3. Empyema: pos gram stain, pus, or pos. culture
How to treat uncomplicated effusion?
Treat the underlying cause
Who to treat empyema?
- Need to put in chest tube
- Antibiotics alone will not do the trick
Worry with loculations?
- One chest tube will not drain all the pockets
- Thoracotomy surgery usually necessary to clear plural space
What is pleurodesis?
- Chemical or mechanical irritation of visceral / parietal pleura creating adhesion and obliteration of space
- You can live without a pleural space so this can be done for treatment
- Surgery or chemical can be used
Is a pleural space necessary for life?
No, elephants do not
Causes of pneumo thorax
*Air in pleural space from following cause:
1. Alveoli rupture
2. Hole in chest wall
What happens in pneumothorax?
- Lungs collapse while chest expands
- Chest Pain
- Shock (if tension)
Appearance of pneumothorax on cxr?
***Very hard to do
- Hyperlucent lung fields
- Lack of “lung markings”
- Thin white pleural line
- Shift of mediastinum if tension
Physical exam in pneumothorax?
- Unilateral Hyperinflation
- Decreased Breath Sounds and Tactile Fremitus
- Hyper-resonance - “tympanitic”
What is Tension pneumothorax?
- You keep sucking air in and can't move it out
- Impedes venous return leading to shock and death
Treatment of pneumothorax?
- Give O2 if observing
- Do not suck air out with needle
- Chest tube
Structure of chest tube?
1. Chamber to catch fluid
2. Suction chamber to move air out
3. Water chamber to prevent from sucking air / water in
Pleura effusion pattern in TB?
Pleura effusion pattern in malignancy?
Exudative, Lymphocytic, RBC’s, +/- low pH/Glucose, Large
Pleura effusion pattern in pulm embolism?
85% are small, unilateral, and exudative; +/- bloody
Pleura effusion pattern in esophageal rupture?
Left sided, low pH, high amylase
Pleura effusion pattern in Endometriosis?
Pleura effusion pattern in “Milky” Effusions?
Chylothorax (TG > 110)
Malignancy, Trauma, Mediastinal Disease (ruptured thoracic duct)
Pseudochylothorax (TG>100 AND Chol > 200)
Chronic Inflammatory Conditions (breakdown of cell walls)