Respiratory Clinical Anatomy Flashcards
What are the rules for a thoracic X-ray?
Always investigate more than one view
Compare slides
Approach x-ray systematically (step by step)
A void order is
+Bony details
-rubs
+ lung fields, parietal and pleural extent
+mediastinal details and subdivisions
-Size and position of the mediastinal structures
Whaat should be looked for in a thoracic X-ray?
- Bony details (count the ribs)
- Lung fields, parietal and pleural extent
- Mediastinal details and subdivisions
- At least 2 views, a PA and lateral
- Penetration thoracic vertebra should be visible in the superior mediastinum
- Assess the position of the patient
- Quality of the image
- Phase of respiration
What is the protocol for a chest x-ray?
In the standard protocol for chest radiography, radiographs are taken in the PA view; this means the film is “in front” of the patient and the x-rays travel through starting from the back
Contrast this with an AP view where x-rays travel starting at the front, this is done when a PA view isn’t possible such as when patient cannot maintain an upright position
Contrast the thoracic cavity and pleural cavity
Thoracic cavity
-Space found in the upper trunk region
- Separated from the abdominal cavity by the diaphragm.
- Protected externally by ribs and muscles
- House important organs (heart, lung, esophagus)
- Contains the mediastinum and three serous cavities
- two pleural cavities
- one pericardial cavity
Pleural cavity
Closed cavities surrounding the lungs
Lined by serous membranes-parietal pleura and visceral pleura
Where do the 2 layers if the pleura meet?
2 layers of pleura meet at the root of the lung-mediastinal pleura meets visceral pleura
What is the pleural recess?
Costompediastinal recess-between costal and mediastinal pleura
Costodiaphragmatic recess-between costal and diaphragmatic pleura
What are the borders of the pleura at the mid clavicular line?
Inferior border of lung- rib 6
Inferior edge of parietal pleura
What are the surface land marks of the pleura at the mid-Axillary line?
Inferior border of lung- rib 8
Inferior edge of parietal pleura- rib 10
What are the surface landmarks of the para vertebral line?
Inferior border of lung- TV10
inferior edge of parietal pleura- TV12
What is a pneumothorax?
Presence of air in the pleural cavity
What are the causes for pneumothorax?
Spontaneous- absence of lung disease, no prior provoking event, ruptured bleb or bullae
Traumatic- introduction of air in the pleural cavity secondary injury to the pleura
Blunt or penetrating trauma
Other causes:
Inflammation
Smoking
Underlying pulmonary disease
Contrast non tension and tension pneumothorax
Non tension pneumothorax- there is no valve mechanism (unsealed opening) as a result there is no build up pressure.
Tension pneumothorax- is the condition in which the air filling the pleural cavity can not escape (forming one-way valve). In this condition the visceral pleura are ruptured. The pressure in the pleural cavity builds up with every breath causing mediastinal shift. This condition leads to severe shortness of breath, as well as circulatory collapse and requires urgent intervention
Why is tension pneumothorax life threatening?
Displacement of structures of the mediastinum interrupting cardiopulmonary function.
Involves visceral and parietal pleura and tracheobronchial tree
What is the mechanism of tension pneumothorax?
- flap valve present
- displacement of mediastinum to opposite side
- Compression of heart and great vessels
Explain the methods if decompression of the tension pneumothorax
Needle decompression
Indication: tension pneumothorax-when thoracostomy isn’t possible in peripheral setting. Tube thoracostomy should follow.
Site 2nd intercostal space in midclavicular line in affected hemithorax
Equipment: large bore needle -14/16 gauge
Tube thoracostomy
Indication: relieve trapped collections of air or fluid in the thorax
Site: 4th or 5th intercostal space between the anterior axillary and mid axillary
How can endotracheal intubation be conducted?
Introduction laryngoscope-
Moves tongue forward
Expose epiglottis and vocal fold
Introduction of endotracheal tube
-Advance tube between the vocal folds and into trachea, 2-3 cm above carina
-Ensure correct tube placement after. Look,listen.
Care should be taken to not cause bleeding or damage to tongue, teeth, epiglottis, vocal cords and other adjacent structures
Aspirate to remove excess
Where is the hilum of the lung?
- Region where the mediastinal pleura meets the visceral pleura
- Several structures enter and leave the lung at this point
What is the structure-function of the root of the lungs?
Attached lung to structures in the mediastinum
Formed by structures entering and leaving the lung.
- Bronchi
- Pulmonary artery (venous blood)
- Pulmonary vein (arterial blood)
- Bronchial arteries
- lymph vessels
- nerves
What are the features/ projections of the medial surface of the right lung?
Superior vena cava
Heart
Inferior vena cava
Azygos veins
Esophagus
What are the features/projections of the medial surface of the left lung?
Heart
Aortic arch
Thoracic aorta
Esophagus
What are the main fissures of the lung?
Oblique fissures begin at the spinous processs of the scapula (TIV) and follows fib VI anteriorly
Hokrizontal fissure follows 4th intercostal space laterally to meet oblique
What is the function of the bronchial tree?
- Aspirated/inhaled foreign objects tend to lodge in wider, shorter and more vertical right bronchus and eventually right lower lobe
- Each lobe segment has own arterial supply, segmental bronchus
Explain the obstruction of airways and Atelectasis
Obstructed airway
-prevents free passage of air resulting in lung collapse
Collapse is distal to obstruction -Atelectasis
Symptoms:
- difficulty breathing (dyspnea)
- coughing
What is the significance of broncho-pulmonary segments ?
- smallest functional unit of lung
- conical in shape
- Surgically respectable without affecting neighboring regions
- Tertiary bronchi supply bronchopulmonary segments
- A branch of pulmonary artery accompany the tertiary bronchi
- drained by pulmonary veins
Explain lung blood circulation
-The segmental bronchi are followed by branches of the pulmonary artery
Pulmonary artery and veins provide blood supply to the visceral pleura as well
Pulmonary vein leave the lung in the intersegmental septa
How do bronchi receive blood?
Bronchial vessels supply the bronchial tree and visceral pleura
- left bronchial arteries- direct branches of aorta
- right bronchial artery from posterior intercostal
Bronchial veins drain into the hemiazygos (left bronchial) and azygos veins (right bronchial)
Summar7ze lymph drainage pattern of lungs and bronchiole tree
- Intra pulmonary Vessels & nodes
- Bronchopulmonary (hilar) nodes
- Tracheobronchial (carrinal) nodes
- Paratracheal nodes
- Bronchomediastinal lymph nodes
- Right thoracic trunk/ thoracic duct
- Systemic venous system
What can be expected in a chest X-ray of a pneumonia patient?
Pneumonia (consolidation) - the normal air- filled spaces of the alveoli become filled with denser material like fluid or pus
What is Acute pulmonary edema?
Collection of fluid in the alveoli
Usually due to cardiac failure, but can be due cardiogenic shock, toxins, pneumonia or medications
What will you find on physical examination of pleural effusion?
Collection of excess fluid in the pleural cavity- blunting of the costcodiaphragmatic recess
Describe the innervation of the lung
- No visceral afferents to the lung and visceral pleura
- Bronchi are Innervated by visceral afferents
Parasympathetics- from vagus nerve bronchoconstriction, vasodilation, and increased muscular secretion by glands
Sympathetics from sympathetic trunks via the cardiopulmonary nerves bronchodilation (beta r3celtors) and vasoconstriction
Nerves are distributed along bronchial tree and pulmonary vessels
