VII: Acid-Base Disorders

Question 1

Respiratory disorder due to

Answer 1

pCO2

Question 2

Metabolic disorder due to

Answer 2

[HCO3-]

Question 3

Metabolic acidosis HCO3- and pH

Answer 3

Low [HCO3-] and low pH

Question 4

Compensation of metabolic acidosis (pCO2)

Answer 4

Hyperventilation to eliminate CO2 (decreased pCO2)

Kidney will compensate to increase HCO3- but it will take longer

Question 5

Metabolic alkalosis

Answer 5

High [HCO3-] and high pH

Question 6

Compensation for metabolic alkalosis

Answer 6

Hypoventilation to keep the CO2 (increase pCO2)

Kidney will secrete HCO3- to decrease its concentration in blood

Question 7

Respiratory acidosis pCO2 and pH

Answer 7

High pCO2 and low pH

Question 8

Compensation for respiratory acidosis

Answer 8

Synthesize more HCO3-

Question 9

Cause of respiratory acidosis

Answer 9

Hypoventilation causing CO2 retention

Question 10

Respiratory alkalosis

Answer 10

Low pCO2 and high pH

Question 11

Compensation for respiratory alkalosis

Answer 11

Kidney will stop producing HCO3-

Question 12

Cause of respiratory alkalosis

Answer 12

Hyperventilation causing CO2 loss

Question 13

Mechanisms to maintaining blood pH in normal range

Answer 13

ICF and ECF buffers (HCO3-)
Respiratory compensation
Renal compensation

Question 14

Use of anion gap of plasma

Answer 14

In diagnosis of acid-base disorders

Question 15

Bases of anion gap

Answer 15

[cations] must equal [anions]
Na+ HCO3- and Cl-
So any unmeasured anions will make up for the “gap”

Question 16

Calculation of plasma anion gap

Answer 16

[Na+] - ([HCO3-] - [Cl-])

Question 17

Normal range of anion gap

Answer 17

8-12mEq/L

Question 18

During metabolic acidosis, what happens to the anion gap

Answer 18

There is a loss of [HCO3-] and because the system has to be in equilibrium, there will be an unmeasured anion replacing the lost HCO3-

Question 19

Anion gap increased during

Answer 19

Diabetic ketoacidosis

Lactic acidosis

Question 20

If HCO3- replaced by Cl-

Answer 20

Hyperchloremic

Question 21

Main cause of metabolic acidosis

Answer 21

Gain of non-volatile H+

Question 22

Buffering of H+ excess by HCO3-

Answer 22

In ECF, HCO3- has decreased so there is buffering in ICF of H+ with organic anions or K+
Use of K+ to buffer can cause hyperkalemia

Question 23

Respiratory compensation of metabolic acidosis

Answer 23

Hyperventilation to decrease pCO2

Question 24

Consequence of hyperventilation in arterial pressure

Answer 24

Arterial pressure drops

Question 25

Renal compensation in metabolic acidosis

Answer 25

Takes a few days H+ is excreted as titrable NH4+ New HCO3- synthesized

Question 26

Metabolic alkalosis loss of fixed acid

Answer 26

H+ loss from stomach | HCO3- is not stimulated so it stays in blood, HCO3- increase

Question 27

Buffering in ECF and ICF in metabolic alkalosis

Answer 27

H+ leaves the cells so K+ enters = hypokalemia

Question 28

Respiratory compensation in metabolic alkalosis

Answer 28

Hypoventilation = increased arterial pressure | To increase pCO2

Question 29

Renal correction in metabolic alkalosis

Answer 29

HCO3- excreted in urine to decrease [HCO3-] in blood

Question 30

What is complicated about HCO3- excretion during vomiting

Answer 30

There is ECF volume contraction which is causing reabsorbtion

Question 31

During ECF depletion (a.k.a vomiting) what happend

Answer 31

Increase in HCO3- reabsorption Increase in angiotensin II to increase Na+/H+ exchange and HCO3- reabsorption Increase in aldosterone for H+ secretion, HCO3- reabsorption and K+ secretion

Question 32

K+ seccretion during ECF contraction can cause

Answer 32

Hypokalemia

Question 33

Main cause of repsiratory acidosis

Answer 33

Increase in pCO2 due to hypoventilation

Question 34

Buffering in respiratory acidosis mainly by

Answer 34

RBC in ICF

Question 35

Renal correction in respiratory acidosis

Answer 35

Increase in H+ excretion as NH4+ | Increase in HCO3- synthesis

Question 36

Main cause of respiratory alkalosis

Answer 36

Loss of CO2 from hyperventilation

Question 37

Buffering in respiratory alkalosis

Answer 37

In ICF by RBC | CO2 out of cell to increase concentration

Question 38

Renal compensation in respiratory alkalosis

Answer 38

Decrease in H+ excretion | Decrease in HCO3- synthesis