Water-Electrolyte Balance / Acid-Base Balance

Flashcards covering key concepts related to water-electrolyte and acid-base balance.

Water intoxication

State in which fluid intake exceeds water output.

ANP

Released in response to increased atrial distention as a result of high blood pressure.

If pH of ECF increases

The kidneys will excrete more hydrogen ions and reabsorb more bicarbonate ions. The respiratory system will compensate hyperventilating.

Na+

Most abundant cation in extracellular fluid.

Metabolic water

Produced in the body during aerobic respiration and dehydration synthesis reactions.

K+

Most abundant cation in intracellular fluid.

Intracellular compartment

Contains about two thirds of the body’s fluid.

Hyperkalemia

Could result from reduced aldosterone secretion and kidney failure.

Kidneys

Primary site of ions loss in the body.

Dehydration

State in which water output exceeds water intake.

Respiratory System

Plays a key role in maintaining acid-base homeostasis by removing CO2.

If pH of ECF drops

The kidneys will decrease hydrogen ions elimination and reabsorb less bicarbonate ions. The respiratory system will compensate decreasing breathing rate.

Metabolic alkalosis

Can be a consequence of hyperventilation, for example in fever or mental illness.

Fluid shift

It is the rapid movement of water between the ECF and ICF in response to an osmotic gradient.

Body’s major buffer systems

Buffer includes phosphate, proteins and carbonic acid-bicarbonate.

Aldosterone

Stimulate Aldosterone release.

ADH

Contribute to produce a low volume of highly concentrated urine when extracellular fluid osmolarity increases due to dehydration. It is inhibited by alcohol

High K+ and Low BP

Inhibits secretion of ADH.

Buffer

Chemical that minimizes the changes in the pH of body fluids by releasing or binding hydrogen ions.

Respiratory alkalosis

Can be caused by prolonged vomiting.

Water balance

Refers to maintaining the correct amount of water in the body.