On a standard reticulocyte preparation with new methylene blue, 100 cells are counted containing blue-stained granulofilamentous material. The red blood count is 3.22 x 1012/L, and the hematocrit is 30%. Calculate the reticulocyte production index (RPI)
a. 1.5
b. 2.7
c. 3.4
d. 13.4
ANS: C
The RPI uses the corrected reticulocyte count (calculated in Question 25). It then takes into account, based on the patient's hematocrit, the early release of RBCs from the marrow so that when the reticulocytes are counted, it is not just those released in the last 24 hours (1 day) but a piling up of those released over a longer period of time. For a hematocrit of 30%, the average length of time a reticulocyte spends in the blood is 2.0 days. Thus the corrected reticulocyte count of 6.7 is divided by 2 = 3.4.
You might also like to view...
You are caring for a 64-year-old woman with chest pain and shortness of breath. She is alert and oriented with an open airway. Her breathing is adequate. She has a normal pulse and her skin is warm and dry. Which of the following should you do next?
A) Obtain her heart rate and blood pressure. B) Prepare for immediate transport. C) Inquire about history of heart problems. D) Hook up the automatic external defibrillator.
The hematopoietic form of acute radiation syndrome is also called the
a. Auger syndrome. b. bone marrow syndrome. c. cerebrovascular syndrome. d. cytogenetic syndrome.