Physiology Review III

Question 1

bicarb buffering system

Answer 1

CO2 > H+ and HCO3-

Question 2

acidosis

Answer 2

pH < 7.35

Question 3

alkalosis

Answer 3

pH > 7.45

Question 4

normal pH, HCO3, and PCO2

Answer 4

pH - 7.4
HCO3 - 24
PCO2 - 40

Question 5

respiratory acidosis

Answer 5

too much CO2 - reaction to right
-increased bicarb

1: 0.1 ratio of CO2 increase to HCO3 increase
- acute uncompensated

Question 6

metabolic acidosis

Answer 6

decreased bicarb

Question 7

respiratory alkalosis

Answer 7

reduced CO2 - reaction to left
-decreased bicarb

1: 0.2 ration CO2 decreased to HCO3 decreased
- acute uncompensated

Question 8

metabolic alkalosis

Answer 8

increased bicarb

Question 9

compensated respiratory acidosis

Answer 9

kidney - days to complete - increased bicarb

1:0.35 CO2 increase to HCO3 increase

Question 10

compensated metabolic acidosis

Answer 10

respiratory - rapid

winters equation - is resp compensating?

predicted PaCO2 = (1.5 x HCO3) + 8

should be +/- 2 of predicted value
-if so - compensation has occured

Question 11

compensated respiratory alkalosis

Answer 11

1:0.5 ratio of CO2 decrease to HCO3 decrease

Question 12

compensated metabolic alkalosis

Answer 12

decreased ventilation

equation to determine if compensation has occured:
predicted PaCO2 = (0.7 x rise in HCO3) + 40

within +/- 2 of predicted value - compensation occured

Question 13

CO2 and bicarb in opposite direction

Answer 13

likely combined disturbance

Question 14

plasma anion gap

Answer 14

PAG = Na - (Cl + HCO3)

to determine cause of metabolic acidosis

Question 15

elevated anion gap acidosis

Answer 15

MUDPILES
methanol
uremia
diabetic ketoacidosis
paraldehyde
iron
lactic acidosis
ethylene glycol
salicylates

Question 16

non-elevated anion gap acidosis

Answer 16

HARDUP
hyperchloremic
acetazolamide
renal tubular acidosis
diarrhea
ureteral diversion
pancreas fistula

Question 17

respiratory vs. metabolic?

Answer 17

respiratory - H and HCO3 both increase/decrease

metabolic - H and HCO3 go opposite

Question 18

hormones of posterior pituitary

Answer 18

ADH and oxytocin

-released from distal neuron terminals

Question 19

ADH synthesis

Answer 19

in supraptic and paraventricular nuclei of hypothalamus

-released from posterior pituitary

Question 20

ADH action

Answer 20

renal collecting duct - V2 receptors

• increased aquaporin channels
• more water reabsorption
• increases urea reabsorption

severe hemorrhage - on V1 receptors of vascular smooth m result in vasoconstriction

Question 21

inhibition of ADH release

Answer 21

stretch receptors send constant (-) signals

Question 22

normal osmolality

Answer 22

kept around 285

Question 23

weightlessness

Answer 23

shift of blood centrally

-increases stretch receptor ADH inhibition

Question 24

alcohol and ADH

Answer 24

inhibits ADH

Question 25

ANP

Answer 25

atrial natriuretic peptide - secreted by heart - right atrium - released with stretch, salt intake, CHF, fluid overload increases sodium and water loss

Question 26

natriuresis

Answer 26

sodium loss

Question 27

diuresis

Answer 27

water loss

Question 28

ANP action

Answer 28

dilates afferent arteriole constriction efferent arteriole increased GFR also, inhibits aldosterone and CD reabsorption of water and Na

Question 29

central diabetes insipidus

Answer 29

not enough ADH to affect renal CDs

Question 30

nephrogenic diabetes insipidus

Answer 30

inability of kidney to respond to ADH -with lithium

Question 31

SIADH

Answer 31

syndrome of inappropriate ADH -excessive secretion of ADH - increase water retention - volume expansion > increased renin > hyponatremia