A 35-year-old female ultramarathon runner is admitted to the ...

[mp14]

A 35-year-old female ultramarathon runner is admitted to the hospital following a day-long, 50-mile race because her urinary volume is drastically decreased and her urine is dark red.
 
  Tests indicate that she is in the initiating phase of acute tubular necrosis. Why is her urine red?
  A)
  Hematuria
  B)
  Hemoglobinuria
  C)
  Myoglobinuria
  D)
  Kidney bleeding

Question 2

When explaining a cystometry test to measure bladder pressure during filling and voiding in a normal adult, the nurse informs the nursing students that the normal capacity when adults have a desire to void is
 
  A)
  100 to 150 mL.
  B)
  200 to 250 mL.
  C)
  300 to 399 mL.
  D)
  400 to 500 mL.

[Rilsmarie951]

Answer to Question 1

Ans:
C

Feedback:

Myoglobinuria, which can cause acute tubular necrosis via intratubular obstruction, involves the leaching of myoglobin from skeletal muscle into the urine, bypassing the usual filtration by the glomerulus. Excess exercise and muscle trauma can contribute to this. While both hemoglobinuria and myoglobinuria discolor the urine, hemoglobinuria results from hemolysis following a reaction to a blood transfusion, whereas myoglobinuria involves muscle damage.

Answer to Question 2

Ans:
D

Feedback:

The desire to void occurs when the bladder is full (normal capacity is approximately 400 to 500 mL). At this point, a definite sensation of fullness occurs; the pressure rises sharply to 40 to 100 cm H2O; and voiding occurs around the catheter.