Pharmacology Plasma Expanders

1. Plasma Expanders
Dr KG Bandekar
MD Pharmacology

2. Body fluid compartments
Total Body Fluid 60 %
Body Wt (42 L)
ECF (20% BW) 14 L
Plasma (5% BW) 3L
Interstitial Fluid
(15% BW)
ICF (40% BW) 28 L

3. Plasma Vs Serum
Plasma
• Plasma is blood
devoid of blood cells.
Serum
• Plasma without
clotting factors

4. Volume expanders
• Intravenous fluids that are used to increase or
retain the volume of fluid in the circulating
blood
• Used to replace fluids that are lost due to
illness, trauma or surgery.
• Do not carry oxygen

5. Ideal properties
1. Iso-oncotic with plasma
2. Distributed to intravascular compartment
only
3. Pharmacodynamically inert
4. Non-pyrogenic & non antigenic
5. Should not interfere with blood grouping or
cross matching
6. Stable, easily sterilizable and cheap

6. Types of volume expanders
1. Crystalloids: aqueous solutions of mineral
salts or other water soluble molecules.
 Normal saline (NS)
 Dextrose
 Ringer’s solution (RL)
2. Colloids: Larger insoluble molecules
 Dextran
 Human albumin
 Gelatin

7. Colloids Vs Crystalloids in volume
expansion
Colloids are better than Crystalloids because:
• Being large molecules retained in the
intravascular space increase osmotic
pressure more effective resuscitation
• Duration of action is relatively longer

8. Colloids

9. Colloids
1. Human albumin
2. Dextrans
3. Degraded gelatin polymer
(Polygeline)..Hemaccel
4. Hydroxy ethyl starch …HES..(Hetastarch)
and…
5. Blood

10. Mechanism of action : Colloids
• Principle of osmosis
• Increases Plasma osmotic pressure,
draws water into plasma from interstitial fluid

11. Osmosis

12. 1. Human Albumin
• Most abundant protein in human plasma
• Hydrophilic
• Accounts for 70% to 80% of the plasma colloid
oncotic pressure (COP)
• Binds to cations, anions, and toxins, such as
bilirubin, gives it an important physiological role
in buffering the acid-base balance of the blood,
transporting proteins and drugs.
• Synthesized in the liver

13. Human Albumin
• Obtained from pooled human plasma.
• Can be used without regard to patient’s blood
group and
• doesn’t interfere with coagulation/ platelet fn.
• It is free of risk of transmission of hepatitis
because the preparation is heat treated.
• Expensive

14. Indications : Albumin
• Rapid volume expansion is req
• Hyopoproteinemia – Liver dis / nephrotic
syndrome

15. ADR : Albumin
• Rare

16. 2. Dextrans
• Glucose polymers ..(found in beet root)
• Obtained by the action of the bacterium
Leucohostoc mesenteroides

17. Dextrans
• Can be stored for 10 years and are cheap

18. Types of Dextrans
a) Dextran 40 (10% solution)
b) Dextran 70 (6% solution)
• Molecular weight is the main factor for effects

19. (a) 6% Dextran 70
• It is most commonly used preparation.
• It expands plasma volume for nearly 24 hrs.
• Excreted slowly by glomerular filtration over
weeks
• Gets deposited in reticulo- endothelial cells

20. 6 % Dextran 70
• Nearly all the properties of an ideal plasma
except:
It may interfere with blood grouping and cross
matching.
 It can interfere with coagulation and platelet
function and thus prolong bleeding time
Some polysaccharide reacting antibodies, if
present, may cross react with dextran and trigger
anaphylactic reaction like Urticaria, itching,
bronchospasm

21. (b) 10 % Dextran 40
• Faster acting than 6 % dextran 70
• More volume expansion than 6 % dextran 70
• Reduces blood viscosity
• Excreted through renal tubules and
occasionally may produce acute renal failure.

22. Contraindications : Dextrans
• ARF
• Hypersensitivity
• CHF
• Bleeding disorders

23. 3. Degraded gelatin polymer
(polygeline)….hemaccel
• Synthetic polymer (polypeptide)
• Doesn’t interfere with blood grouping and
cross matching
• Non-antigenic
• More expensive than dextran
(e.g : Haemaccel)

24. Indications : Gelatin polymers
• Rapid correction of intravascular vol
• Prophylactic – before major surg

25. 4. Hydroxy ethyl starch (HES)
(Hetastarch)
• Complex mixture of ethoxylated amylopectin
of various molecular sizes
• No RF or coagulation disturbances

26. Advantages : HES
1. Non antigenic
2. No interference with bld grouping
3. No interference with coagulation / platelet
action
4. Do not interfere with renal fn
5. Less expensive than 5 % Albumin
6. Longer duration of action ….~ 24 hrs

27. Disadvantages : HES
• Increases S. amylase levels for 4-5 days

28. Colloids
Not causing Bleeding /
antigenicity
1. Human Albumin
2. Degraded gelatin polymer
…hemaccel
3. HES
Causing Bleeding /
antigenicity
• ????
1. Dextrans

29. Crystalloids

30. Crystalloids
• Electrolyte solutions with small molecules that
can diffuse freely throughout the extracellular
space
• 75-80% of infused crystalloid is distributed in
interstitial space
• Expands interstitial volume rather than plasma
volume
• Minimal impact on intracellular volume.

31. Types of Crystalloids
• Isotonic: Isotonic to plasma
NS
Ringer’s Lactate
• Hypotonic
• Hypertonic

32. Composition
Fluid Na+ Cl- K+ Ca+ pH Glucose Osmolarity Tonicity Use
Plasma 142 108 4.2 1.3 7.4 ~ 0.85 ~ 290 - -
NS 154 154 0 0 5.7 0 308 Isotonic Resuscitation
RL 130 109 4 3 6.4 0 273 Isotonic -do-
D5 0 0 0 0 50 252 Hypotonic i) Na+
ii) Hypo
glycemia

33. NS
• 1 liter NS ….9 grams NaCl (154 mEq Na)
• 650ml of NS provides…~ 5.9 gram NaCl (100
mEq Na)
• ( Daily req of Na ~ 5.9 grams)
• No glucose ---- use in DKA

34. NS
• NaCl is mainly extracellular….(physiology)
• NS is used to provide extracellular electrolytes

35. NS: When to be given?
1) Shock: fluid volume deficit (hemorrhage, Severe
vomiting or diarrhea,
2) Mild hyponatremia
3) Metabolic acidosis (eg. diabetic ketoacidosis)
4) Fluid of choice for resuscitation efforts
5) Only fluid used with administration of blood
products
6) Head injury patients….being slightly hypertonic

36. NS
• Osmolarity ~ 308
• Slightly hypertonic

37. Contraindications of NS
• HTN
• Patients with edema/ fluid overload states
(CHF)

38. Disadvantage
• Metabolic acidosis – due to high chloride
concentration (Hyperchloremic acidosis)

39. RL
• Most physiological fluid
• Sodium lactate is metabolized in liver to
bicarbonate.
• Corrects metabolic acidosis

40. Indications : RL
• Hypovolaemia
• Metabolic acidosis

41. Contraindications: RL
• Liver diseases
• Along with Blood transfusion….???
• Ca+2 in RL – binds with citrate
(anticoagulant)….promotes clots in donor
blood…..Not to administer in in one i.v line

42. DNS
• 5% dextrose + 0.9 %NaCl
• Provides energy (dextrose) and Extracellular
fluid & electrolytes (isotonic saline)
• Can lead to large glucose load
• Hyperglycemia induced osmotic diuresis
• In partially corrected shock increase
urine output

43. Thank you!