11-09-2010, 07:23 AM
21) A 14 year old girl is admitted to the hospital after sustaining injuries in a house fire. Her temp is 37.2 C (99 F), pulse is 115/min, respirations are 9/min, & bp is 100/65 mmHg. Physical examination shows second-degree burns over 40% of her body surface area. Labs show:
Serum:
Na+ : 138 mEq/L
K+ : 4 mEq/L
Urea nitrogen: 90mg/dL
Creatinine: 3.5mg/dL
Urine:
Na+ : 3 mEq/L
Osmolarity: 1220 mOsmol/kg
Excreted fraction of sodium:
A decrease in which of the following is the most likely explaination for lab findings;
A: collecting duct free water reabsorption
B: distal tubule k secretion
C:distal tubule Na reabsorption
D: glomerular filtration
E: proximal tubule Na reabsorption
the answer that someone put is C but I think it should be E, look at urine osmolarity which is making me think that because of decrease blood flow, PCT is not absorbing Na/K because it is sensitive to hypotension ??? can some one help, but her serum Na looks normal which means that PCT is fine...but y is osmolarty so high???
Serum:
Na+ : 138 mEq/L
K+ : 4 mEq/L
Urea nitrogen: 90mg/dL
Creatinine: 3.5mg/dL
Urine:
Na+ : 3 mEq/L
Osmolarity: 1220 mOsmol/kg
Excreted fraction of sodium:
A decrease in which of the following is the most likely explaination for lab findings;
A: collecting duct free water reabsorption
B: distal tubule k secretion
C:distal tubule Na reabsorption
D: glomerular filtration
E: proximal tubule Na reabsorption
the answer that someone put is C but I think it should be E, look at urine osmolarity which is making me think that because of decrease blood flow, PCT is not absorbing Na/K because it is sensitive to hypotension ??? can some one help, but her serum Na looks normal which means that PCT is fine...but y is osmolarty so high???