| What is pleura? | It is the space between parietal and visceral pleura, contains 0.3ml/kg of hypo-oncotic fluid, which is all the time changed, produced by parietal pleura from up and gets reabsorbed from down
Exception where visceral pleura forms it is in case of heart failure, increasing hydrostatic pressure and thus forming liquid from plasma in capillaries. |
| What are the abnormalities of pleura? | Pleural effusion (pleurisy ) and pneumothorax.
When filtration exceeds maximum pleural lymphatic flow effusion occurs (max flow is 30ml/h to 700 ml/h) |
| What is pleural effusion? | When fluid collects in pleural space |
| What are the symptoms of pleural effusion? | Pleuritic pain (due to parietal pleura interacting with liquid , felt at the site of effusion, knife-like pain increased with breathing and could irritate the shoulder)
Dyspnea (correlated with size of effusion)
Dry cough (due to lung compression)
Orthopnea (impaired sleep) |
| What are the physical exam findings of pleural effusion? | Diminished breath sounds or absence at site of effusion (bu sthetoscope) with basal dullness in percussion
Tachypnea may be present with large effusion.
Pleural rub may be heard initially with parapneumonic effusion. |
| What are the imaging findings in case of pleural effusion? | X ray (PA and lateral view reveals 200ml effusion (PA) and 50 ml (lateral))
US (very useful, if multiple punctures, guides the pleural tap (decreasing the risk of iatrogenic pneumothorax))
Chest CT (reveals spots not seen on X ray, provides potential causes of the effusion- white spots are atelectasis- damaged alveoli, shouldn't be punctured!) |
| What are the indications for thoracocentesis? | Dx: puncture to discover the type of fluid accumulated
Therapeutic: to get better breathing and decompression of lung tissue (for bilateral)
Done under guide of US to reduce the risk of iatrogenic pneumothorax
Needle is inserted at the upper part of the rib (where no innervation and vascularization) after anesthesia
We should get rid of fluid periodically and gradually (max 1L/tap since it may cause ARDS if very rapid) |
| What is the difference between atelectasis and effusion on X ray? | Atelectasis shrinks the mediastinum while effusion doesn't |
| What is the normal pleural fluid? | hypo oncotic (low protein)
More alkaline than blood (pH=7.6)
we usually get this fluid and test in labs (culture, TB, cytopathy for cancer)
May be transudate or exudate (transudate is more common) |
| What is the difference between transudate and exudate? | Transudate (increased hydrostatic pressure or low plasma onotic pressure, pleural proteins/plasma <0.6)
Exudate (increased oncotic pressure due to inflammation of capillaries, pleural proteins/plasma proteins >0.6)
This is light criteria (Protein ratio >0.5, LDH concentration in effusion >200 or LDH ratio >0.6) |
| What are the causes of transudate pleural effusion? | Commonly congestive heart failure, nephrotic syndrome or cirrhosis with ascites.
Less common are dialysis, urinothorax, atelectasis, pulmonary embolism, myxedema |
| What are the causes of exudate pleural effusion? | Commonly malignancy, parapneumonic effusion, pulmonary embolism, TB, pancreatitis, postcardiac injury
Less common infection, sarcoidosis, asbestosis |
| What is malignant pleural effusion? | Lung carcinoma is the most common neoplasma, then breast then lymphomas and ovaries
Mesothelioma (asbestosis) |
| What is pneumothorax? What are the types? | Collection of air or gas in pleura, puts pressure on the lung and may collapse it.
Types include spontaneous (primary like blip for tall thin individuals in europe, or secondary with underlying disease like COPD)
Tension pneumothorax (presses lungs and heart could lead to an arrest and causes hypotension)
Traumatic pneumothorax (caused by chest injuries) |
| What are the diseases associated with 2ary spontaneous pneumothorax? | COPD, asthma HIV infection, necrotizing pneumonia, bronchogenic carcinoma, sarcomas, TB, CF, interstitial lung disease, idiopathic fibrosis, sarcoidosis... |
| What are the S&S of pneumothorax? | Sudden dyspnea and pleuritic chest pain (more severe for 2ary sponaneous type)
Significant cardiorespiratory symptoms -->check tension pneumothorax. |
| What are the radiological findings in case of pneumothorax? | If lung margin is >2cm from chest wall at hilum-->pneumothorax
CT scan more sensitive, US may be helpful also |
| What is the PE findings in case of pneumothorax? | No sound at all with auscultation. |
| How is the management of pneumothorax? | driven by symptoms, if pneumothorax <2cm --> self-limited.
Thoracostomy is imp for tension pneumothorax (chest tube)
stop smoking after first episode and cancel flight plans and scuba diving
could provide oxygen if needed when no bubbles found on chest tube |
