Chap 9-Acids&Bases Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

pH =

pH is the

A

potential hydrogen

concentration of hydrogen ions (H+)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The pH of blood indicates the net_______

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Human blood must maintain a_________ pH range

Blood =

A

very narrow; 7.35 – 7.45

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

less than _____or greater than ____death occurs

A

< 6.8 or > 8.0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q
One Proton (+)
One Electron (-)
A

electrically balanced

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

An Acid is…

A

A molecule that can donate a H+ ion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

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

A

pH

to 7
to 1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

A Base or alkali is…

A

A molecule that can accept a H+ ion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

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

A

pH

7
14

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

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

A

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.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

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

Ex:

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

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.

A

0 - 14; acidic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q
not important Acids and bases can be:
 Strong –\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_
ex: 
 Weak –\_\_\_\_\_\_\_\_\_\_\_
ex:
A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

pH scale = 1 to 14

The p-function operator means the negative logarithm of.

A

pH = -log [H+]

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

In this case, a range of 100 to

A

10-14 onto a range of 1 to 14.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Calculate [H+] for pH of 7.4?

A

0.00004mEq , 40nEq/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Calculate nano equivalents shortcut

A

[H+] = 10 (9-pH)

18
Q

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

10^-3 M

A

pH= 3.00

19
Q

ABG Analysis indicates

A

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

20
Q

pH_______
PaCO2_______
HCO3- _______
PaO2 ________

A

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

21
Q
ABG Interpretation
Step 1:
Step 2:
Step 3:
Step 4:
A
  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

  1. 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”
22
Q

what is the cut off for compensated vs uncompensated

A

pH ph 7.35 - 7.40 compensated acidosis

ph 7.40-7.45 compensated alkalosis

23
Q

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

A

uncompensated metabolic alkalosis

24
Q

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

A

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

25
Q

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

A

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

26
Q

Buffer systems

A

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

27
Q

Carbonic acid (H2CO3) –

A

Bicarbonate buffer system –

28
Q

most important ECF buffer against non-carbonic acid

changes

A

Carbonic acid (H2CO3) –

29
Q

Protein buffer system (includes Hgb) –

A

LARGEST buffer in the body; important ICF and ECF buffer

30
Q

Protein buffer system (includes Hgb) –

A

LARGEST buffer in the body; important ICF and ECF buffer

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

31
Q

List 3 buffers mechanisms

A

Bicarbonate buffer syterm
Protein Buffer system
PHOSPHATE Buffer system

32
Q

Phosphate buffer system –

A

important intracellular and urinary buffer

33
Q

Note about buffer

A

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

34
Q

Kassirer-Bleich equation:

A

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

pH if PCO2 and HCO3 are known)

35
Q

What does the Kassirer-Bleich equation do

A

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.

36
Q

Metabolic Acidosis/Alkalosis =

Respiratory Acidosis/Alkalosis =

A

disturbances of bicarbonate

disturbances of PaCO2

37
Q

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

A

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+]).

38
Q

When a primary acid-base disturbance alters one

component of the PCO2/[HCO3- ] ratio,

A

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

39
Q

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

A

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

40
Q

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

A

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.

41
Q

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.

A

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.