Chap 9-Acids&Bases

Question 1

pH =

pH is the

Answer 1

potential hydrogen

concentration of hydrogen ions (H+)

Question 2

The pH of blood indicates the net_______

Answer 2

result of normal acid-base regulation, any acid-base imbalance, and the body’s compensatory mechanisms

Question 3

Human blood must maintain a_________ pH range

Blood =

Answer 3

very narrow; 7.35 – 7.45

Question 4

less than _____or greater than ____death occurs

Answer 4

< 6.8 or > 8.0

Question 5

One Proton (+)
One Electron (-)

Answer 5

electrically balanced

Question 6

An Acid is…

Answer 6

A molecule that can donate a H+ ion

Question 7

An acid can be weak, moderate, or strong depending on its ________
Weaker acids are closer______
Stronger acids are closer to_____

Answer 7

pH

to 7
to 1

Question 8

A Base or alkali is…

Answer 8

A molecule that can accept a H+ ion

Question 9

A base can be weak, moderate, or strong depending on its pH
Weaker bases are closer to pH __
Stronger bases are closer to pH ____

Answer 9

pH

7
14

Question 10

Bronsted Theory
An acid is _______
A base is_______
When an acid donates it proton, what remains is called what?

Answer 10

Defines an acid as a proton, or H+ ion donor.
A base is a proton acceptor.
When an acid donates its proton, what remains is called
the conjugate base.

Question 11

When a base accepts a proton, it is converted into its

Ex:

Answer 11

conjugate acid.
NH3 + H+ = NH4+ (ammonia to ammonium)
HCO3- + H+ = H2CO3 (bicarb to carbonic acid)

Question 12

pH Range is from________
If [H+] is high, the solution is________; pH < 7
↑ H+ ↓ pH (Acidic)
If [H+] is low, the solution is basic or alkaline ; pH > 7
↓ H+ ↑ pH (Alkaline)
Acids are H+ donors.
Bases are H+ acceptors, or give up OH- in solution.

Answer 12

0 - 14; acidic

Question 13

not important Acids and bases can be:
 Strong –\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_
ex: 
 Weak –\_\_\_\_\_\_\_\_\_\_\_
ex:

Answer 13

dissociate completely in solution
HCl, NaOH
dissociate only partially in solution
Lactic acid, carbonic acid

Question 14

pH scale = 1 to 14

The p-function operator means the negative logarithm of.

Answer 14

pH = -log [H+]

Question 15

In this case, a range of 100 to

Answer 15

10-14 onto a range of 1 to 14.

Question 16

Calculate [H+] for pH of 7.4?

Answer 16

0.00004mEq , 40nEq/L

Question 17

Calculate nano equivalents shortcut

Answer 17

[H+] = 10 (9-pH)

Question 18

Example: Calculate pH of a solution when the [H+] is 1.0 x

10^-3 M

Answer 18

pH= 3.00

Question 19

ABG Analysis indicates

Answer 19

how well a patient is exchanging gases in the lungs and how well the body is maintaining normal pH.

Question 20

pH_______
PaCO2_______
HCO3- _______
PaO2 ________

Answer 20

7.35 – 7.45
35 – 45 mmHg
22 – 26 mEq/L
80 – 100 mmHg

Question 21

ABG Interpretation
Step 1:
Step 2:
Step 3:
Step 4:

Answer 21

1. check PaO2 (80-100)
   < 80 = hypoxic, > 100 = hyper-oxygenated (mask, ventilation, etc)
2. check pH (7.4)
   7.35 – 7.45 = compensated acidosis or alkalosis
   < 7.35 = uncompensated acidosis, > 7.45 = uncompensated alkalosis

3.check PaCO2 (35-45) alkalotic or acidotic range?
Correlate with pH – if both pH & CO2 match, cause = respiratory

4. check HCO3 (22-26) acidotic or alkalotic range?
   Correlate with pH – if both pH & HCO3 match, cause = metabolic
   If all 3 (pH, CO2 & HCO3) match, cause = “combined”

Question 22

what is the cut off for compensated vs uncompensated

Answer 22

pH ph 7.35 - 7.40 compensated acidosis

ph 7.40-7.45 compensated alkalosis

Question 23

PaO2: 90
pH: 7.52
PaCO2: 43
HCO3: 30

Answer 23

uncompensated metabolic alkalosis

Question 24

PaO2: 90
pH: 7.52
PaCO2: 29
HCO3: 30

Answer 24

“Combined Alkalosis Combined Alkalosis” because ” because both CO2 and HCO3 are CO2 and HCO3 are
contributing to the pH alkalosis

Question 25

Compensated – pH in range w/ both #s off
Uncompensated –
Partially Compensated -
Combined –

Answer 25

pH out of range w/ one off & one normal
pH out of range w/ both #s off
pH out of range w/ both #s contributing

Question 26

Buffer systems

Answer 26

Prevent major changes in pH by removing or releasing
hydrogen (H+) ions
Act chemically to change strong acids into weaker acids or to bind acids to neutralize their effects

Question 27

Carbonic acid (H2CO3) –

Answer 27

Bicarbonate buffer system –

Question 28

most important ECF buffer against non-carbonic acid

changes

Answer 28

Carbonic acid (H2CO3) –

Question 29

Protein buffer system (includes Hgb) –

Answer 29

LARGEST buffer in the body; important ICF and ECF buffer

Question 30

Protein buffer system (includes Hgb) –

Answer 30

LARGEST buffer in the body; important ICF and ECF buffer

Hemoglobin buffer system –primary buffer against carbonic acid changes (via arbaminohemoglobin)

Question 31

List 3 buffers mechanisms

Answer 31

Bicarbonate buffer syterm
Protein Buffer system
PHOSPHATE Buffer system

Question 32

Phosphate buffer system –

Answer 32

important intracellular and urinary buffer

Question 33

Note about buffer

Answer 33

Buffer systems do not eliminate H+ from or add them to the body but only keep them tied up until balance can be reestablished by compensatory mechanisms

Question 34

Kassirer-Bleich equation:

Answer 34

[H+] = 24 x PCO2/HCO3 ¯ (allows calculation of [H+] and

pH if PCO2 and HCO3 are known)

Question 35

What does the Kassirer-Bleich equation do

Answer 35

Reflects how the acidity of blood is determined by the relative availability of acid and alkali (HCO3¯ & PaCO2)

Stresses how H+ ion concentration is determined by the ratio of PCO2/HCO3, rather than the absolute value of either value alone.

Question 36

Metabolic Acidosis/Alkalosis =

Respiratory Acidosis/Alkalosis =

Answer 36

disturbances of bicarbonate

disturbances of PaCO2

Question 37

A normal [H+] of 40 nEq/L corresponds to a pH of 7.40.

Answer 37

Because the pH is a negative logarithm of the [H+], changes in pH are inversely related changes in [H
+] (e.g., a decrease in pH is associated with an
increase in [H+]).

Question 38

When a primary acid-base disturbance alters one

component of the PCO2/[HCO3- ] ratio,

Answer 38

the compensatory response alters the other component in the same directionto keep the PCO2/[HCO3- ] ratio constant.

Question 39

Respiratory acidosis PCO2_____HCO3 _______
Respiratory alkalosis PCO2 ______ HCO3 _______
Metabolic acidosis HCO3 _____PCO2 ______
Metabolic alkalosis HCO3_____ PCO2_______

Answer 39

up ; up
down; down
down; Down
up; up

Question 40

For acute respiratory disturbances (where renal
compensation does not have much time to occur)
each arterial PCO2 _________________while for chronic respiratory disturbances (where renal compensation
has time to occur) each PCO2 shift of

Answer 40

shift of 10 mm Hg is accompanied by a pH shift of about 0.1,

10 mm Hg is accompanied by a pH shift of about 0.03.

Question 41

In our case an arterial PCO2 shift of 25 mm Hg (from 40 to 65 mm Hg) is accompanied by a pH shift of 0.10 units (from 7.40 to 7.30), or a 0.04 pH shift for each PCO2 shift of 10 mm.

Answer 41

Since 0.04 is reasonably close to the expected value of 0.03 for an chronic respiratory disturbance, it is reasonable to say that clinically the patient has chronic respiratory acidosis.