This document discusses different types of parenteral fluids used in medical treatment. It covers crystalloids like normal saline and Ringer's lactate, which are preferred due to lower cost and side effects. It also discusses colloids, balanced salt solutions, maintenance fluid volume and type, tonicity versus osmolarity, comparisons of common crystalloid solutions to plasma, and fluids used for resuscitation in dehydration or shock.

1. Parenteral Fluids

2. Crystalloids
 Crystalloids are the preferred fluids (e.g. Normal Saline,
Ringer Lactate).
 They are equally efficacious than colloids and are
cheaper, easily available and lesser side effects.
 Only about 1/3 of these fluids tend to stay in the
intravascular compartment, rest leak out.

3. Crystalloids
 Balanced Salt Solutions ( e.g. Plasmalyte/ Kabilyte )
are special crystalloids with the same sodium and
chloride composition of plasma.
 Lesser chloride content, so better, prevents
AKI/persistent acidosis .

4. Colloids
 Sticky fluids that always stay in the intravascular
compartment
 E.g. Albumin, Gelofusin, FFP

5. Maintenance
Fluid
Type
 These fluids are required when the oral rehydration and
fluid intake is not possible and only intravenous fluid is
needed.
 These fluids are required to provide energy/glucose and
to sustain cellular functions like metabolic activities,
transport, maintaining cellular functions and integrity.
 This they need to have Glucose and basic electrolytes
and given in a specific volume. Other electrolytes suck
as KCl are already present in the fluids (RL, Kabilyte)

6. Maintenance
Fluid
Volume
 Use the Holliday Segar Method
 First 10 kg 100ml/kg
 Next 10 kg 50ml/kg
 Next kg 20ml/kg

7. Tonicity
&
Osmolarity
 Osmolarity :
- Number of osmoles of solutes per kg of solution
- Concentration of permeable & impermeable solutes
- 2x[Na] + [glucose]/18+ [BUN]/2.8
 Tonicity ( Effective osmolarity ) :
- Concentration of non-permeable solutes
- 2x[Na] + [glucose]/18

8. Tonicity
of
Fluids
 Osmolarity of the fluid will determine how much solute
(sugar salt) is there in a solvent/water.
 More the osmolarity Hyperosmolar More
concentrated the fluid when put across a cell
membrane it exerts more osmotic force and draws
water towards it.
 Plasma osmolarity (275-295 osm/L) is determined by
sodium, glucose and urea.

9. Tonicity
of
Fluids
 Fluids when containing Glucose and Sodium. The
Glucose gets easily metabolized hence these osmoles
are ineffective. Thus sodium is the only effective
osmole in fluids. This effective osmolality is called
Tonicity
 Put simply tonicity is how much Sodium is there in the
fluids. When it is similar to plasma it is called
ISOTONIC and when less or more it is called
HYPOTONIC and HYPERTONIC .

10. Why Isotonic ?
 Hypotonic fluids will cause fluid shift across the cell
membrane hence we need to AVOID them. They may
cause hyponatremia
 Hence we choose dextrose containing isotonic fluids as
maintenance fluids e.g. DNS, Balanced fluids
(Plasmalyte, Kabilyte)

11. Crystalloid
solutions
compared to
human plasma

12. Crystalloid
solutions
compared to
human plasma
Sodium
(mmol/L)
Potassium
(mmol/L)
Chloride
(mmol/L)
pH Theoretical
Osmolarity
(mOsmol/kg)
Actual or measured
osmolality
(mOsmol/kg)
Plasma 136-145 3.5-5.0 98-106 7.35-7.45 291 287
Sodium Chloride
(0.9%)
154 Nil 154 4.5-7 308 286
Ringer’s Lactate 130 4 109 5-7 278 256
Plasma-Lyte 148 140 5 98-106 5.1-5.9 309

13. Various Fluids
&
Osmolarity/
Tonicity
Na K Cl Dex Osm Tonicity
NS 154 154 308 Isotonic
DNS 154 154 50 560 Isotonic
½ DNS 77 77 50 406 Hypotonic
Isolyte P 26 20 21 50 346 Hypotonic
RL 130 4 109 273 Isotonic
10% D 0 100 Hypotonic
5% D 0 50 Hypotonic

14. Resuscitation
Fluids
 These fluids are given to replace a fluid deficit
in the body.
 Fluid deficit may be either Dehydration or
Shock
 In dehydration the loss is mainly from the
interstitial compartment and fluid replacement is
typically based on the percentage of dehydration
& given slowly over few hours.
 Shock is circulatory failure where the fluid loss
is mainly from intravascular compartment space.
Here the fluid should be given rapidly.

15. Type of fluid
for
resuscitation
 Fluid used is isotonic non dextrose containing
crystalloids – Normal Saline, Ringer Lactate or
Plasmalyte