Other AcidBase things

Question 1

What are strong ions?

Answer 1

compounds that are fully dissociated at physiologic pH

Question 2

List the strong ions

Answer 2

• Na+, K+
• Ca++, Mg++
• Cl-
• lactic acid
• ketoacids
• SO4–

strong ion difference = difference between positive and negative charges

Question 3

What determines Atot?

Answer 3

• proteins (albumin, globulin)
• PO4–

Question 4

How does the strong ion difference affect acid base status?

Answer 4

decreased SID - acidosis
increased SID - alkalosis

Question 5

How will Atot affect acid base status?

Answer 5

acidosis from increases in Alb, Glo, P

alkalosis from Atot uncommon - values are already very high, not likely to go low enough to cause alkalosis

Question 6

What are the 3 mechanisms causing strong ion disorders?

Answer 6

1. change in free water - changes Na+ more than Cl- (dilutional acidosis decrease in cations more than anions)
2. change in Cl-
3. increase in unmeasured strong anions

Question 7

What is the recommended dosing of sodium bicarbonate?

Answer 7

body weight x volume of distribution (Vd) x (desired HCO3- - current HCO3-)

volume of distribution 0.2-0.5
desired HCO3-&raquo_space; conservative: 10-12 mEq/L

Question 8

List potential adverse effects of Na bicarbonate

Answer 8

• alkalosis
• paradoxical cerebral acidosis
• intracellular acidosis
• hypokalemia
• hypernatremia
• hypocalcemia
• lowering BP (vasodilation from HT solution administration)

Question 9

What is the Henderson Hasselbach equation for pH?

Answer 9

pH = 6.1 + Log (HCO3-) (0.03 x PCO2)