Pleura and pleural space Flashcards
Pleural effusion
Cannot be distinguished on radiographs. Interlobar fissure lines are the earliest sign of excessive fliud in the pleural space and appear as thin, curved, soft tissue opacity lines between lung lobes. (Lateral)
Pleural effusion on (DV/VD) keep in mind the _____ _____
mediastinal reflection (cranioventral and caudoventral)
Fissure line difference in relation to fluid vs. pleural thickening vs. fat.
Fluid creates fissure lines that are wider periperally and taper toward the hilus. Pleural thickening creates lines that are uniform in thickness and do NOT taper. Fat (obese animals) can fill interlobar fissures and create lines that are wider centrally and taper peripherally. (Reverse fissure lines)
Finding in radiographs with increased volume of pleural fluid in realation to lung boarders.
- Lung borders retract from thoracic wall spine, sternum and diaphram. With large effusions, lung lobes will be small and may appear leaf like. Vascular and bronchial markings do NOT extend to thorachic wall.
Finding in radiographs with increased volume of pleural fluid in realation to thoracic cavity contents
Increased opacity, costophrenic angles b/c rounded and indistinct, caudolateral lung margins appear blunted, ventral lung margins b/c scalloped and outlined by fluid, cardiac silhouette and trachea are dorsally displaced (depending on volume of fluid), cranial mediastinum may appear widened due to summation with adjacent fluid, cardiac and diaphragmatic borders b/c obscured, diaphram caudally displaced.
Rounding of lung lobe borders suggest ______ ______, which restricts lung ______ and can lead to lung rupture during rapid ______.
pleural fiborsis, expansion, re-expansion
Asymmetric or unilateral pleural effusion occurs with _____ _____, which obstruct mediastinal fenestrations and may cause a mediastinal shift ____ from fluid.
inflammatory conditions
AWAY
Parietal pleura lines what?
- thoracic wall
- mediatinum
- diaphragm
What kind of pleura covers the lungs?
Pulmonary or visceral pleura
Parietal pleura flods back on itself at ____ __ ____ to become _____ _____.
root of lungs
pulmonary pleura
Types of pleura
- Parietal Pleura
- –Cervical Pleura
- –Thoracic Pleura
- –Diaphragmatic Pleura
- –Mediastinal Pleura
- Visceral Pleura
Pleural fluid is continuoulsy produced by ____ ____, released into pleural space and reabsorbed by _____ _____ (75% turnover every____)
Parietal pleura, pulmonary pleura, hour
Causes of DECREASED opacity of pleural space is pneumothorax. What are the top 3 causes of pneumothorax?
- Trauma (common)- erforation of thoracic wall, ruptured lung or airway, tear in pulmonary pleura, ruptured esophagus.
- Iatrogenic- thoracocentesis, lung aspirate, Thoracotomy, aggressive CPR, transthoracic biopsy of liver, hyperinflation (anesthsia)
- Spontaneous- idiopathic, rupture from cavitary mass (bleb, bulla, cyst), neoplasia
3 reasons for increased opacity in the pleural space and pleura
- Pleural effusion
- Pleural thickening
- Pleural mass
Causes for Pleural effusion- first cause for increased opacity in pleural space
Transudate/ modified transudate- Transudate= flid is thin, clear w/ low SG, low protein, low fibrin, and low cell count (results from pressure filtration w/o capillary damage)
Modified transudate= fluid is serous to serosanguinous, may contain a vriety of cell types (often inflammatory) and can lead to restrictive pleuritis or unilateral pleural effusion.
Hemothorax- fluid resembles peripheral blood, but may not clot and is rapidly reabsorbed
Pyothorax or emyema - fluid is exudative w/ lg # of neutrophils
Chylothorax- fluid appears milky due to chylomicrons (small fat globules) and lymphcytes
Pseuro-chylous effusion- (fluid is sterile and inflammatory)
Pyogranulomatous effusion- fluid is thick, viscous, strw colored, exudative w/ very high protein, high SG, few inflammatory cells, fluid may clot
Unilateral or asymmetic PE
Conditions that may mimic PE
Effusion types visual-
- Straw
- Blood
- Purulent
- Chylous
Causes of transudate
hypoprteinemia (nephrotic syndrome- glomerulonephritis, protein-losing nephropathy, protein-losing enteropathy, hepatic insufficiency), Iatrogenic fluid overload, CHF (right ventricular fail, pericardial effusion), Lymphatic neoplasia (lymphoma), fibrosis, adhesions
Causes of hemothorax
- Trauma
- Neoplastic erosion (hemangiosarcoma)
- Coagulopathy (rodenticide)
- Autoimmune disease
- Heartworm disease (errosion through vessel)
- Sp[irocercosis (errosion through vessel)
Causes for pyothorax or empyema
- systemic infection (most common)- Bacterial, viral, mycotic, nocardiosis, Tuberculosis
- Foreign material
- Pneumonia
- Lung abscess
- Autoimmune dz (lupus erythematosus, Rheumatoid arthritis)
Causes for chylothorax
- MOST COMMON Thoracic duct rupture (iatorgenic, trauma, idiopathic)
- Thoracic duct blockage (neoplasia, thrombosis, fibrosis, conginital malformation)
- Lymphangiectasia- is the dilation (expansion) of the lymphatic vessels in thegastrointestinal tract, which includes the stomach, small intestines, and large intestines. Lymphangiectasia is an obstructive disorder of the lymphatic system of the gastrointestinal tract, resulting in the loss of body proteins through the intestines.
- Heart failure (cats)
Causes of Pseudo-chylous effusion (sterile inflammitory fluid)
- Idopathic (dog)
- Lymphosarcoma (cat)
- Cardiomyopathy (cat)
Causes for pyogranulamatous effusion
- MOST COMMON - Feline infectious peritonitis
- meoplasia (mesothelioma)
Causes of unilateral or asymmetrical pleural effusion
- Functionally complete mediastinum
- Sever pulmonary dz and altered lung compliance
- Trapped fluid (unequal distribution, but moves with gravity)
- Encapsulated fluid (does not move with gravity and retains it’s shape)
Conditions that mimic pleural effusion
- Underexposed radiographs
- Body conformation- chondrodystrophic breeds (Bassett Hounds, Dachshund) Cats- epaxial musculature in dorsocaudal thorax on lateral radiograph.
- Obesity- excessive fat along sternum, in mediastinum, and b/t lung lobes
