How to cure cirrhosis and chronic hepatitis naturally
acid base balance: part 1
1. ACID BASE BALANCE
Dr. Ifat Ara Begum
Assistant Professor
Dept. of Biochemistry
Dhaka Medical College
Dhaka
2. CLASS PLAN
Basic facts: Repetition
Regulation of acid base balance
Pathophysiology of different
acid base disorders
3. DAY-1
Review on acid/base/pH/ buffers/
H-H Equation
Origin of acids and bases in our
body
Acidity of solution
pH & the effects of pH change
4. ACIDS
These are the molecules having
hydrogen atom and can donate
hydrogen ion ( H+
/ Proton) in
aqueous solution.
In simple words:
Acids are H+
/ Protondonor
7. CONJUGATE BASE OF AN
ACID
Conjugate base of an acid is the
anionic part of an acid after
removal of proton from the acid
8. C
Rapidly &
completely ionized
in solution (body
fluids) into H+ & its
conjugate base.
Degree of
dissociation &
dissociation
constant is high
pK value: Low
Slowly & partially
ionized in solution
(body fluids) into H+
& its conjugate base.
Degree of
dissociation &
dissociation
constant is low
pK value: High
Strong Acid Weak Acid
9. As conjugate base
shows less affinity to
H+, rapid and
complete ionization
to proton occurs. So,
conjugate bases of
strong acids are
weak.
Example: All
inorganic acids
except H2CO3
As conjugate base
shows strong affinity
to H+, slow and
partial ionization to
proton occurs. So,
conjugate bases of
weak acids are strong.
Example: All organic
acids and H2CO3
Strong Acid Weak Acid
10. BASES
These are the molecules that can
accept H+
(Proton) in aqueous
solution.
In simple words, bases are H+
/
Proton acceptor
After accepting proton, conjugate
acid of that base is formed.
Bases may be charged like Cl-
,
HCO3
-
or without charge like NH3
12. C
Have greater
tendency to accept
proton.
Bind rapidly &
strongly with proton,
so, remove them
quickly from solution
Conjugate acid: weak
Example: HCO3
-
Have low tendency
to accept proton.
Bind slowly &
weakly with proton,
so, remove them
slowly from solution
Conjugate acid:
strong
Example: Cl-
Strong Base Weak Base
15. STRENGTH OF ACID/BASE
Strength is defined in terms of the
tendency to donate (or accept) the
hydrogen ion to (from) the solvent
(i.e. water in biological systems)
16. SOURCES OF ACID / BASE IN
BODY FLUID
Endogenous source: Produced at
cellular level during metabolism
Exogenous source: Potentially
acidic/basic substances get entry in to
the body fluid through
enteral/parenteral route. i.e. via
1. Foods rich in acid (meat)
2. Ingestion of acids (salicylic acid)
3. Intravenous infusion
17. I) POTENTIAL SOURCES OF
VOLATILE ACID
Complete oxidation of glucose & FA
Oxidation of AA
18. II)POTENTIAL SOURCES OF
NON VOLATILE ACID
Oxidation of :
basic AA : 130 mmol/Day
S-containing AA: 70 mmol/Day
PO4 containing subs: 30 mmol/Day
--------------------------------------------------------------
Total : 230 mmol/D
19. III) POTENTIAL SOURCES OF
BASE
Oxidation of acidic AA : 100 mmol/Day
Metabolism of dietary organic anions
(citrate/acetate) :60mmol/Day
---------------------------------------------------------------
Total = 160 mmol/D
20. AT A GLANCE, ACID& BASE
PRODUCTION IN 70 KG ADULT AT
NORMAL METABOLIC STATUS
Volatile acid (CO2/H2CO3): 15-20 mol/D
Non-volatile acid: 230 mmol/D
Base: 160 mmol/D
21. CONTD
NVA & base neutralize each other at
one to one ratio. So, after
neutralization, 70 mmol/D NVA is left
behind (230-160 = 70)
This 70 mmol/D of NVA, along with
15-20 mol/D of volatile acid makes
the body env. acidic
22. JUSTIFY: OUR BODY IS NET
ACID PRODUCER
Although body produces both acids &
bases , in normal condition, rate of acid
production is higher than the rate of base
production.
So, normally body is regarded as net acid
producer producing net 15-20 mol/D of
volatile acid & 70 mmol/D of non-volatile
acid.
Body may be net base producer
pathologically
23. METABOLIC ACID OR BASE
PRODUCTION DEPENDS ON
Insulin status: Deficiency leads to acid
production
Blood flow / Oxygen supply to tissues:
Decreased flow/hypoxia leads to acid
production
Dietary habit: Protein generates more
acid, fruits generate more alkali,
vegetables generate less acid
24. ROUTES OF ACID/BASE
DISPOSAL
Respiratory Route Renal Route
High capacity
system, because,
dispose huge acid
load.
Low capacity system,
because, dispose
moderate acid load.
Excretes volatile
acids only
Excretes non-
volatile acids and
base as well
Unidirectional , i.e.
excrete only acid
Bidirectional , i.e.
excrete both acid &
base
25. CONTD
Respiratory Route Renal Route
Functional reserve
is up to 10-20 times
normal
Functional reserve
is up to 5-10 times
normal
Complete failure for
few minutes
reduces pH grossly
Complete failure for
few minutes has no
effect on pH at all.
26. ACIDITY OF A SOLUTION
State of H+
conc. of a solution.
Or
A measure of a solution’s capacity to
react with a strong base (usually
sodium hydroxide, NaOH) to a
predetermined pH value.
This measurement is based on the total
acidic constituent of a solution
It is directly proportional to the acid
content & indirectly proportional to the
base/alkali content of the solution.
27. CONTD
It can be measured in :
Arithmetic scale: Has a definite
absolute unit and measures acidity by
exponential expression (10-7
mol/L) or
by decimal expression (0.001mol/L)
OR
Logarithmic scale (pH scale): Has no
unit
28. EXPRESSION OF ACIDITY OF
BODY FLUID
In logarithmic
scale (pH)
In arithmetic scale
(H+
concentration
in nmol/L)
7.35 45
7.45 35
29. PH
OF A SOLUTION
Negative logarithm of hydrogen ion
concentration of a solution, when H+
concentration is expressed in terms of
mol/L
30. CONTD
If pH is 7.0 :
H+
concentration = 10-7
mol/L
= 10-7
x 109
= 100 nmol/L
33. CONTD
Normal blood pH: 7.35 – 7.45 (average
7.4)
Arterial pH: 7.35-7.45
Venous pH: 7.32-7.42
Clinically safe range of pH : 7.3 - 7.5
Normal H+
concentration of blood: 35 –
45 nmol/L
pH compatible to life: 6.8 – 7.8
pH at which life is impossible: >7.8 or
<6.8
35. PH SCALE
The pH scale measures how acidic or
basic a substance is.
It covers the practical range of acidity &
alkalinity of solutions commonly
encountered and it ranges from 0 to 14
A substance that is neither acidic nor
basic is neutral
36. ICF PH
ICF pH is slightly lower than that of
ECF/blood as cellular metabolism
produce acids. It is 7.0 – 7.3, though it
varies from cell to cell
Determined by the degree of cellular
metabolic function and tissue perfusion
37. CONTD
Changes in ECF pH causes parallel but
laser changes in ICF pH
Although it determines the cellular
activity, as it is difficult to measure ,
ECF pH is used for clinical evaluation,
which is easy to measure and nearly
reflects the ICF pH.
38. IMPORTANCE OF NORMAL
BODY PH
It supports optimum enzyme
activity for smooth running of
metabolism.
It is concerned with oxygen-Hb
dissociation & association
relationship as well as chemical
control of respiration.
39. CONTD
It maintains:
i. Native molecular form &
structural conformation of bio-
molecules, esp. protein, at which
they are functionally active.
ii. Internal environment and cellular
viability by tuning proper
electrolyte distribution in ECF via
Na+ _
K+
pump
iii. Optimum vascular resistance
40. WHY DOES LIFE THREATEN
BEYOND CLINICALLY SAFE
RANGE OF PH
There is Altered :
i. enzyme activity
ii.membrane permeability
iii.CNS activity
iv.electrolyte distribution
There is increased myocardial
irritability
There is decreased cellular
viability
45. CONTD
H+ ions are very reactive cations
Proteins are anions at body pH
H+ ions at higher concentrations
can bind strongly to negatively
charged proteins, including
enzymes, and impair their activity
and hence the cell function.