General Patho: lab values, RAS, stress response

Question 1

arterial pH

Answer 1

7.35-7.45

Question 2

serum potassium

Answer 2

3.5-5.0 mmol/L

Question 3

male hemoglobin (different units)

Answer 3

14-18 g/dL
140-180 g/L
8.7-11.2 mmol/L

Question 4

female hemoglobin (different units)

Answer 4

12-16 g/dL
120-160 g/L
7.4-9.9 mmol/L

Question 5

serum sodium

Answer 5

135-145 mmol/L

Question 6

Briefly describe the RAS (renin-angiotensin system)

Answer 6

Low BP, blood volume, renal perfusion –> renin by kidneys –> stimulates conversion of angiotensinogen to angiotensin I –> in lungs, AT I converted to AT II by ACE –> ATII causes peripheral vasoconstriction –> increases SVR –> increases BP
vasoconstriction by AT II causes decreased glomerular filtration –> increased Na+ and water reabsorption –> increased blood volume –> increased BP
AT II stimulates release of aldosterone by adrenal medulla –> Na+ and water retention by kidney tubules –> increased blood volume and BP

Question 7

Briefly differentiate between adrenal medullary and cortical responses to stress

Answer 7

Medulla: NEP and EP released
Short-term response to stress (not-essential to life)
Increased glycogenolysis
Bronchodilation, increased RR, HR, heart contractility
increased energy use by all cells
shunting of blood from periphery to heart, brain, and skeletal muscles

Cortex: essential to life
Gluconeogenesis with lipolysis and proteolysis
Mineralocorticoids important in fluid/electrolyte balance