Which of the following is the right order at which the lines are depicted in the image given below?
A.
Line 1 -Perfusion from bottom to top of the lungs.
Line 2 – VA / QC from bottom to top of the lungs.
Line 3 – Ventilation from bottom to top of the lungs.
B.
Line 1 – VA / QCfrom bottom to top of the lungs.
Line 2 – Perfusion from bottom to top of the lungs.
Line 3 – Ventilation from bottom to top of the lungs.
C.
Line 1 – VA / QC from bottom to top of the lungs.
Line 2 – Ventilation from bottom to top of the lungs.
Line 3 – Perfusion from bottom to top of the lungs.
D.
Line 1 – Perfusion from bottom to top of the lungs.
Line 2 – Ventilation from bottom to top of the lungs.
Line 3 – VA / QC from bottom to top of the lungs.
Show Answer
Correct Answer � A
Explanation
Ans. A.
Line 1 -Perfusion from bottom to top of the lungs.
Line 2 – VA / QC from bottom to top of the lungs.
Line 3 – Ventilation from bottom to top of the lungs.
Detailed explanation:
Line 1 represents blood flow (perfusion) from the bottom to the top of the lung.
Note the greater gradient for perfusion than for ventilation (line 3).
Line 2 represents VA / QC (the ventilation/perfusion ratio) from the bottom to the top of the lung.
Note that the ratio is lowest at the bottom of the lung and greatest at the apex of the lung, and that ventilation and perfusion are best matched in the middle of the lung.
Line 3 represents ventilation from the bottom to the top of the lung.
The gradient for ventilation is not nearly as steep as the gradient for perfusion.
