Fluid, Electrolyte, and Acid-Base Balance Lecture Flashcards

Flashcards covering the composition of extracellular and intracellular fluids, the causes and effects of dehydration and overhydration, potassium regulation, and the mechanisms of respiratory and metabolic acidosis.

Sodium

The #1 positive ion in the blood (Extracellular Fluid).

Chloride

The #1 negative ion in the blood (Extracellular Fluid).

Overhydration

A condition occurring when blood becomes hypotonic to cells, causing water to flow into the Intracellular Fluid via osmosis.

Lyse

The process where cells fill with fluid and burst, which can occur during fatal overhydration.

Overhydration Causes

Overtreating dehydration too quickly after exercise, Kidney Failure, excessive ADH secretion, or giving water to babies less than $6$ months.

Overhydration Symptoms

N/V, headache, confusion, seizures, and death, caused by blood being too dilute around neurons surrounded by bone.

Dehydration

A condition where water loss is greater than water gain, concentrating electrolytes and making blood hypertonic to cells.

Crenation

The process where water leaves cells to enter the blood (ECF) during dehydration.

Dehydration Causes

Excessive sweating, water deprivation, hyposecretion of aldosterone or ADH, and eating disorders involving vomiting or diarrhea.

Potassium ($K^+$)

The ion found in its highest concentration inside the cells, which also possesses a low therapeutic index.

Aldosterone

A hormone whose basic function is to save sodium to the blood and eliminate excess potassium to the urine.

Hypokalemia

A decrease in blood $K^+$ levels caused by hypersecretion of aldosterone, moving too much potassium to the urine.

Hyperkalemia

Elevated blood $K^+$ levels caused by either hyposecretion of aldosterone or metabolic acidosis where the kidney prioritizes $H^+$ excretion.

Hypercapnia

Elevated $CO_2$ levels due to low ventilation, resulting in a decrease in blood pH.

Respiratory Acidosis

A disturbance caused by hypoventilation leading to increased $Pco_2$ and decreased blood pH.

Arterial and CSF chemoreceptors

Receptors that are stimulated by increased $Pco_2$ to trigger the body's homeostatic response to acidosis.

Kidney Response to Acidosis

The organs secrete $H^+$ ions and generate $HCO_3^-$ to help restore normal acid-base balance.

Lactic Acid

A metabolic acid that accumulates during strenuous exercise, such as in a marathon runner, leading to metabolic acidosis.

Metabolic Acidosis

A condition where blood pH becomes low due to increased $H^+$ not caused by $CO_2$, such as from lactic acid or chronic renal failure.

Carbonic Acid

A weak acid that dissociates into water and $CO_2$ to be exhaled, which helps improve acidosis and bring pH back up.

Diabetes mellitus

A condition that can cause metabolic acidosis when a patient is noncompliant with treatment.

DRG

The area in the brain that increases respiratory rate as a response to both respiratory and metabolic acidosis.

Protein buffer amino group

A part of the protein buffer system that functions as a weak base to absorb hydrogen from the blood.

Carbonic acid buffer system

A system that is only efficient in helping offset metabolic acidosis and cannot buffer against acidosis caused by $CO_2$.

Bicarbonate ($HCO_3^-$)

An ion that is high in the blood and constantly reabsorbed by the kidneys; its depletion during severe diarrhea causes metabolic acidosis.