IV Fluids

A) Crystalloid solutions (< 30 000 Dalton):

1-Hypotonic solutions:

- D₅W, ½ NS, D5 ¼ NS, D5 ½ NS.

2-Isotonic solutions:

- NS, Ringer’s, Lactated Ringer’s (Hartmann’s), Ringer’s acetate.

3-Hypertonic solutions:

- NaCl (3%, 7.5%), Mannitol (10%, 20%), NaHCO₃ (5%, 7.5%, 8.4%).

B) Colloid solutions (> 30 000 Dalton):

1-Blood derived:

- Human albumin (5%, 25%).

- Plasma protein fraction 5%.

2-Synthetic:

a) Dextrose Starches:

- They are D-glucose polymers linked by alpha bonds into linear macromolecules prepared from sucrose.

- Their half-life is 12 hours.

- 6% Dextran-70 (Macrodex) MW = 70 000 Dalton

- 10% Dextran-40 (Rheomacrodex) MW = 40 000 Dalton

- Dextran-1 (Promit).

- Dose: 20 ml/kg/d., Max.: 1.5 L/d.

Disadvantages:

- Interfere with blood typing.

- Antiplatelet effect.

- Antigenic effect with anaphylactoid and anaphylactic reactions.

- Affects renal functions and can be associated with renal failure.

b) Gelatins:

- Their M.W. 30 000-35 000 Dalton.

- Their half-life is 4-5 hours.

- Succinylated Gelatin (Gelofusine 3.5%, 4%).

- Polygelline (Hemaccel 3.5%, Hemagel 4%).

- Dose: 20 ml/kg/d., Max.: 1.5 L/d.

Advantages:

- Does not interfere with blood grouping.

- Does not affect renal function.

Disadvantages:

- Histamine-mediated allergic reaction.

c) Hydroxy-Ethyl Starch (HES) (Etherified Starch):

Synthetic colloids resemble glycogen structurally, synthesized from amylopectin.

- Heta-starch (Hexa-starch) (e.g. HAES-Steril, Hespan): M.W. 450 000 Dalton, half-life 48 hours.

- Hextend: M.W. is higher, and the half-life is longer.

- Penta-starch: M.W. 200 000, half-life less than 24 hours.

- Tetra-starch: (e.g. Tetraspan, Voluven): M.W. 130 000, half-life less than 6 hours.

- Dose: 20-50 ml/kg/d.

Advantages:

- Do not affect the coagulation study.

- Not antigenic but can cause anaphylactoid reactions.

- Less expensive than human albumin.

Categories: Fluid & Electrolyte disturbances