20- Fluid and Electrolyte Balance

Flashcards on Fluid and Electrolyte Balance

Capillary Blood Pressure (PH)

Hydrostatic pressure (~55 mm Hg) that favors filtration in the glomerulus.

Capillary Colloid Osmotic Pressure (π)

Pressure due to proteins in plasma (~30 mm Hg) that opposes filtration, pulling fluid back to the plasma.

Capsule Fluid Pressure (Pfluid)

Hydrostatic pressure inside Bowman’s capsule (~15 mm Hg) that opposes filtration.

Kidney

Primary route for excreting ions and water from the body.

Lungs

Losing water and bicarbonate (via CO2).

Diuresis

Removing excess water in urine.

Vasopressin (Arginine Vasopressin or Antidiuretic Hormone)

Hormone that controls water reabsorption by acting on collecting ducts only.

Loop of Henle - Renal Countercurrent Multiplier

Transfers solutes by active transport (ascending limb) into the medulla, resulting in greater extracellular fluid osmolarities.

Vasa Recta

Removes water in the renal countercurrent multiplier system.

Renin

Enzyme secreted by juxtaglomerular cells when blood pressure decreases, initiating the renin-angiotensin system.

Aldosterone

Steroid hormone produced in the adrenal cortex that controls sodium balance by promoting sodium reabsorption and potassium secretion in the distal tubules and collecting ducts.

Natriuresis

Urinary Na+ loss.

Atrial Natriuretic Peptide (ANP or Atriopeptin)

Peptide produced in atrial myocardial cells that decreases blood volume by dilating afferent arterioles, decreasing Na+ reabsorption, and suppressing RAS.

Salt Appetite

Craving for salty foods when plasma Na+ levels drop.

Diabetes Insipidus

Low vasopressin activity, disrupting fluid balance.

Syndrome of Inappropriate ADH (SIADH)

High vasopressin activity, disrupting fluid balance.

Acidosis

Condition where neurons become less excitable, leading to CNS depression.

Alkalosis

Condition where neurons become hyperexcitable, potentially leading to muscle tetanus.

Ketoacids

Organic acids produced during metabolic processes which, under extraordinary conditions, can lead to ketoacidosis.

Respiratory Acidosis

Respiratory condition due to hypoventilation, leading to increased PCO2 and decreased pH.

Metabolic Acidosis

Metabolic condition due to dietary and metabolic input of H+ exceeding excretion, leading to a decrease in pH.

Respiratory Alkalosis

Respiratory condition due to hyperventilation, leading to decreased PCO2 and increased pH.

Metabolic Alkalosis

Metabolic condition due to loss of H+ or excessive ingestion of bicarbonate, leading to an increased pH.