What is the Difference Between Hartmann’s Solution and Normal Saline?

Hartmann's solution and normal saline are both intravenous fluids used for different purposes in medical settings. However, they have distinct compositions and physiological effects:

1. Composition: Normal saline is a simple solution containing sodium chloride in water, while Hartmann's solution is a balanced isotonic solution containing sodium, chloride, potassium, calcium, and lactate ions, with lactate being used to generate bicarbonate ions.
2. Physiological Effects: Hartmann's solution is considered to be more "physiological" than normal saline due to its similar electrolyte composition to that of plasma. Excretion of both water and sodium is slower after a 2-liter intravenous bolus of 0.9% saline than after Hartmann's solution, which may be attributed to the more physiological [Na(+)]/[Cl(-)] ratio in Hartmann's solution (1.18:1) than in normal saline.
3. Usage: Both Hartmann's solution and normal saline are useful for medical purposes. Hartmann's solution is primarily used as a resuscitation fluid and for fluid maintenance in patients with low blood volume or acute blood loss. Normal saline, on the other hand, is used as a cleaning agent for wounds, a vehicle for drug administration, and to avoid dehydration.
4. Acidosis: A common misconception is that Hartmann's solution cannot be used for patients in severe acidosis. However, lactic acid and lactate are distinct entities, and Hartmann's solution contains lactate, which generates alkalising HCO3– ions.

In summary, the main differences between Hartmann's solution and normal saline are their compositions and physiological effects. Hartmann's solution is considered more "physiological" and is primarily used for resuscitation and fluid maintenance, while normal saline has a range of medical applications but is not recommended for fluid maintenance alone due to the risk of hyperchloraemic acidosis.

Comparative Table: Hartmann’s Solution vs Normal Saline

Hartmann's solution and normal saline are both intravenous fluids used for fluid resuscitation and maintenance. Here is a table comparing the differences between the two:

Hartmann's solution is considered more physiological than normal saline because it contains other electrolytes in concentrations similar to plasma, making it a balanced isotonic solution. It distributes in both intra-vascular and interstitial spaces, making it useful for both resuscitation and fluid maintenance. On the other hand, normal saline is an isotonic solution with a slightly higher chloride concentration than plasma, which can cause hyperchloremic metabolic acidosis when administered rapidly. It is also contraindicated for heart failure and renal impairment due to the lack of calcium and the higher chloride concentration.