Respiratory Flashcards
(242 cards)
1 What’s the point of the nasal conchae?
They induce turbulent airflow which maximizes exchange efficiency
1 What do the tubercles of each rib articulate with?
The transverse process of the inferior vertebra
1 What type of muscle is the diaphragm and what is it’s innervation?
Skeletal muscle - Phrenic nerve (C3,4,5)
1 Where in an intercostal space should you insert a chest drain?
Just above the inferior rib to avoid the neurovascular bundle
1 Describe the hiatuses of the diaphragm
Vena cava T8, Oesophagus T10, thoracic duct/aortic hiatus T12
1 Describe the venous drainage of the intercostal spaces around the heart
Intercostal veins -> azygous system -> superior vena cava
1 Which bronchus are aspirated objects more likely to settle in and why?
Right bronchus as it is more vertical
1 Which lobes of the lung are you listening to when you ausculate from the back?
Inferior
1 Name the 2 recesses of the pleural cavity
Costodiaphragmatic and retrosternal
1 Why should you consider the lungs when placing a central line?
Because the pleura extends above the 1st rib
1 How high up the anterior trunk does the diaphragm extend?
Highest point of dome is 4th intercostal space on R side and 5th ICS on L side
2 List the accessory muscles of breathing
Sternocleidomastoid Scalenes Pectoralis major and minor Trapezius Internal intercostal muscles Muscles of Abdominal wall
2 How do you calculate alveolar ventilation rate?
(tidal volume - anatomical deadspace volume) x respiratory rate
2 What’s the physiological deadspace of the lungs?
The volume of air which is inhaled that does not take part in the gas exchange, either because it (1) remains in the conducting airways ( ie upper respiratory tract) or (2) reaches alveoli that are not perfused or poorly perfused.
2 What’s the Functional Residual Capacity?
Volume of air remaining in lungs at end of passive exhalation.
2 How does emphysema cause a barrel chested appearance?
Destruction of lung architecture results in increased compliance, causing hyperinflation of the lungs. Chest wall then becomes hyperexpanded and thus rounder or “barrel” shaped.
2 What potential pathophysiological features of the lung could cause an obstructive pattern on spirometry?
Mucus hypersecretion
Decreased radial traction / fewer attachments between airway and parenchyma
Hypertrophy of smooth muscle
Oedema (restrictive too)
2 What’s the formula for calculating airway resistance?
Pressure drop over airway divided by flow through airway
2 Why do we need a pleural seal?
Allows maintenance of negative pressure which forces lungs to follow expansion of chest wall while still allowing elasticity of lung to produce passive deflation when inspiratory muscles relax. Without it the lungs would collapse (pneumothorax).
3 List the parts of the diffusion barrier at the air-blood interface in the lung
Endothelium of capillary, collagen based extracellular matrix, surfactant and water layer and squamous epithelial cells of alvelous
3 How could you estimate total CONCENTRATION of oxygen in the blood?
Multiply partial pressure of gas in the blood by its solubility coefficient.
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Estimated Amount of O2 bound to haemoglobin ( ie Hb concentration x Hb saturation x O2 carrying capacity of Hb)
3 Why does partial pressure of O2 in inspired air decrease as it passes through the upper respiratory tract?
Saturation with water vapour
3 Why does fast ascent from scuba diving risk decompression sickness / “the bends”?
Doesn’t give nitrogen enough time to be exhaled as it comes out of solution in the body fluids.
3 Explain how high altitude can cause hypoxia even through if % of oxygen is still roughly 21%
Air is less compressed at higher altitudes meansing that there is a lower amount of oxygen in the volume of inhaled air.