*2.1.1 Introduction*


the fastest medication to obtain in an emergency. Typical dose of two ampules of hypertonic bicarbonate is equivalent to �200 ml of 3% saline [8]. See

• Depending on the pathology, hyponatremia will be treated differently [9].

• In patients with ADH absent states, hyponatremia is caused because patient is drinking more fluid than the kidney can handle. In primary polydipsia, fluid

• Normally the kidneys require solute to create urine therefore in patients with poor nutritional status, a normal amount of water/alcohol will cause

can be given isotonic fluid is clinical evidence of hyponatremia [9].

• ADH absent states are high risk for over-correction therefore should be

*Maximum Urine Output* <sup>¼</sup> *Dietary Solute Intake*

Normal diet contains 600-900 mosmol of solute/day and the minimum urine osmolality is 60 mosmol/kg therefore the maximum urine output (see Eq. 1) in a

Therefore, in patients with primary polydipsia, they will overcome the maximum urine output while patients with reduced solute intake will have reduced

*Maximum Urine Output* <sup>¼</sup> <sup>900</sup>

*Urine Osmolality* (1)

<sup>60</sup> <sup>¼</sup> <sup>15</sup> *litres per day*

hyponatremia. In patients with reduced dietary solute intake (such as chronic alcoholics), instituting a proper diet will correct hyponatremia. These patients

**Figure 2**.

*Electrolytes in the ICU*

*DOI: http://dx.doi.org/10.5772/intechopen.96957*

**Figure 1.**

restriction would be ideal [9].

*Diagnostic approach to hyponatremia, starting with osmolality.*

monitored closely.

normal patient would be:

maximum urine output.

**139**
