Answer to Question #53915 in Human Anatomy and Physiology for Neda

Question

A 5 year old child had some days of nausea & vomiting.Now his mucous & mouth dry.He is lethargic also.
Describe his monitored changes of FF, GFR & RPF?(mark whether decrease or increase)

Answer 1

Continuous vomiting causes the loss of salts and water. Dry mucous and mouth confirm this condition. If person becomes hypovolemic autoregulation will occur: kidneys try to conserve water and salts. Angiotensin II will cause the constriction of efferent arteriole. It will greatly decrease RPF (renal plasma flow). Additional vasodilation of afferent arteriole will maintain or slightly decrease GFR (glomerular filtration rate). Very law GFR levels can be caused by kidney failure disease.
FF (filtration fraction) = GFR/RPF. Due to the great decrease in RPF FF will increase.
So, FF – increases, RPF – decreases (much), GFR – decreases (slightly) or is constant.