What structures traverse the diaphragm, and at what vertebral levels do they pass through?
8: IVC
10: esophagus, vagus nerve
12: aorta, thoracic duct, azygos vein
What histological change takes place in the trachea of a smoker?
metaplasia (ciliated columnar –> squamous)
What cell type proliferates during lung damage?
type 2 pneumocytes
What amniotic fluid measurement is indicative of fetal lung maturity?
lecithin-sphingomyelin ratio >2
a young woman has infertility, recurrent URIs, and dextrocardia. Which of her protein is defective?
dynein
If a lung collapses, what happens to the intrathoracic volume?
Intrathoracic volume increases due to unopposed chest wall expansion
What gene mutation can cause primary pulmonary HTN?
BMPR-2 gene
What are some of the secondary causes of pulmonary HTN?
What are some of the treatment options available for pulmonary HTN? (4)
What is the MoA of bosentan?
competitively antagonizes at the endothelin-1-receptor (decreasing pulmonary vascular resistance)
Which form of hemoglobin A has a high affinity for oxygen? Which has a low affinity for oxygen?
R form (relaxed) - high affinity T form (taut) - low affinity
What substances tend to shift the oxygen-hemoglobin dissociation curve to the right? (5)
Does this favor oxygen loading or unloading?
What is the treatment for methemoglobinemia?
methylene blue + vit C
What is the normal value for the A-a gradient?
10-15 mmHg
What might an elevated A-a gradient indicate? (5)
What changes occur in the oxygen content and saturation in anemia?
What is the V/Q at the apex of the lung? At the base of the lung?
apex: V/Q > 1
base: V/Q
What is the V/Q during airway obstruction? during blood flow obstruction?
airway obstruction: towards 0 (shunt)
blood flow obstruction: towards infinity
How is CO2 transported from the tissues to the lungs? (3)
How do CO2 levels in circulation change during exercise?
- increase in venous CO2
How does the body compensate for hypoxia at high altitudes? (6)
At what positive G-force does visual “black-out” occur? Why does this occur?
What physiologically is taking place in decompression sickness?
By what physiological mechanism does acute mountain sickness cause acute cerebral edema and acute pulmonary edema?
- pulmonary edema: local vasoconstriction –> forces fluid out of capillaries