Alveolar collapsing pressure - proteus

[ArchivalUser]

is it not 2t/r correct me if wrong

[ArchivalUser]

sorry 2 is constant

[ArchivalUser]

what is the answer?

[ArchivalUser]

E


2T / R to the power of 4


2x2 / (1/16) = 32

[ArchivalUser]

B

[ArchivalUser]

Choice (B) is the correct answer. Alveolar collapsing pressure (P) is described by the equation:

P = (2 x surface tension) / radius

Alveolar collapsing pressure is proportional to surface tension and inversely proportional to radius. If surface tension is doubled and the radius is decreased by a factor of two, the alveolar collapsing pressure will increase by a factor of 4. This is essentially what happens in neonatal respiratory distress syndrome. Premature infants are born with immature lungs that are unable to secrete surfactant, which results in a significant increase in surface tension. In addition, the alveoli of premature infants have a smaller radius than term infants. As a result, the alveoli in premature infants have a tendency to collapse as a result of increased collapsing pressure. Treatment with surfactant acts to reduce surface tension and reduce the collapsing pressure.