Intravenous route is by far the most common method for parenteral fluid therapy. Mostly, the median cubital vein in the cubital fossa is used for venepuncture.
Important Solutions commonly used:
# 5% Dextrose - Isotonic solution that supplies calories but not electrolytes.
- Used when the patient requires replenishment of his blood volume along with some nutrition, but no electrolytes.
- Particularly used in the immediate post operative period when Na excretion is considerably diminished by renal conservation.
# Isotonic (0.9%) Sodium Chloride Solution
- It is isotonic and contains Sodium and chloride ions in the concentration almost similar to that of plasma.
- It should not be used in first 24 hours after surgery due to natural sodium conservation.
- One important fact is that it contains a high concentration of Chloride as compared to that in plasma and imposes an appreciable load of excess Cl on the kidneys that cannot be readily excreted.
# Ringer's Lactate Solution
- Its main advantage is that it has almost similar electrolyte concentration as ECF (extracellular fluid) and the pH remains normal even if infused in large quantities.
- This solution is best to be used in hypovolemic shock while awaiting for blood.
- The chief disadvantage is its slight hypo-osmolarity with respect to sodium.
# Darrow's Solution
- This is the only solution which contains more potassium than available in the plasma or ECF.
- This is the best solution to combat hypokalemia.
- The rate of infusion should be slower than other solution to avoid hyperkalemic state.