Sodium (Na+)

Which is the most ABUNDANT extracellular CATION?

Na+ SODIUM

What is the reference range for SODIUM (Na+)

135-145 mmol/L

What is the major function of Sodium (Na+)?

helps to maintain Osmotic Pressure extracellularly

What 3 factors regulate sodium concentration?

ADH (water)

Aldosterone which again RETAINS Na+

Thirst

What is HYPOnatremia?

Decrease in SODIUM

What value indicates HYPOnatremia?

<135

What are the 4 causes of HYPOnatremia?

Na loss (diarrhea, vomiting)

Dilution

SIADH (soaked inside)

Pseudohyponatremia (Increase of lipids / proteins)

What is SIADH?

SOAKED INSIDE ADH

EXCESS of ADH causing too much water retention, so DILUTES SODIUM

What are the 4 symptoms and progression seen in hyponatremia (moderate to lethal)

Nausea → confusion → seizures → Coma

What is HYPERnatremia?

Excess of sodium (Na+)

What is the value for HYPERnatremia?

>145

What are 3 causes of HYPERnatremia?

Water loss

DECREASED water intake

Na gain

What are the 3 symptoms seen in HYPERnatremia from moderate to lethal?

Irritability → seizures → death

How can Diabetes insipidus cause HYPERnatremia?

IMPAIRS ADH so the body does not hold the water

What is the MAIN method of detecting Sodium?

Ion Selective Electrode (ISE)

What are the two methods that can be done with the ISE?

Direct and Indirect

Which method of ISE causes false sodium decrease due to DILUTION of plasma?

Indirect

Which ISE method is the most accurate method?

DIRECT since it uses no dilution

What condition of sodium is seen only with the INDIRECT ISE?

Pseudohyponatremia