How do you present the image adequacy?
R - Rotation - Spinous processes at midpoint between medial ends of the clavicles?
I - Inspiration - 5 to 7 anterior ribs intersecting the diaphragm in the mid-clavicular line?
P - Penetration - Spine visible behind the heart?
How would you evaluate a CXR?
Patient demographics, projection, adequacy, airway, breathing, circulation, diaphragm, dem bones.
What is the normal percussion finding?
What does it mean if the lung is dull on percussion?
Increased tissue density
What does it mean if the lung is stony dull on percussion?
Presence of a pleural effusion
What does it mean if the lung is hyperresonant on percussion?
Decreased tissue density
What is the normal breathing that is heard over the lung fields?
Vesicular breathing with long inspiration and short expiration without a gap - seen in the smaller airways
Describe the nature of the breathing usually heard in the trachea
Bronchial breathing - Inspiration and expiration of equal lengths with a gap in between.
What is the main cause of bronchial breathing heard over the lung fields?
Consolidation due to lobar pneumonia
What are the main causes of reduced breath sounds?
Pleural effusion, pneumothorax, lung collapse
In what conditions may a wheeze be heard?
In what conditions may crackles be heard?
Pneumonia, bronchiectasis or fluid overload
When would you do an AP CXR?
AP views are less useful and should be reserved for very ill patients who cannot stand erect.
How can you differentiate between an AP/PA CXR?
In AP the heart is magnified and scapula can be seen
What is a pleural effusion?
Collection of fluid within the pleural space
What would you expect to see on a CXR of pleural effusion?
Uniform white area with a loss of the costophrenic angle. The hemi diaphragm is obscured and there is a meniscus at the upper border.
What is consolidation?
Filling of small airways with pus, blood, fluid or cells causing dense opacification on a CXR
What are space occupying lesions?
Nodules with a mass >3cm usually caused by malignancy. e.g. multiple metastasis
What would you expect to see on a CXR with lobar lung collapse?
Elevation of the ipsilateral hemidiaphragm, crowding of the ipsilateral ribs, shift of the mediastinum towards collapse and crowding of the pulmonary vessels. Here there is collapse of the left upper lobe, the right middle lobe and the right lower lobe.
How do you estimate cardiac index?
Ratio between the heart and thorax on a PA image. Usually <50%.
How would a pneumothorax show on a CXR?
Visible pleural edge with lung markings not visible beyond the edge. May see a tracheal/ mediastinal shift away from the pneumothorax and a depressed hemi diaphragm (tension pneumothorax)
What are the causes of lobar lung collapse?
Aspirated foreign body, mucous plugging, bronchogenic carcinoma, compression by adjacent mass