Fluid and Electrolyte Imbalance

Q: What are the two main types of IV fluids?

A: Crystalloids and colloids.

Q: When are oral fluids typically used?

A: Mild to moderate fluid deficits.

Q: What are crystalloids commonly used for?

A: Maintenance fluids and replacing losses.

Q: What are colloids used for?

A: Plasma volume expansion in conditions like shock and burns.

Q: What do hypotonic fluids do?

A: Shift fluid into cells.

Q: What do isotonic fluids do?

A: Keep fluid in the bloodstream.

Q: What do hypertonic fluids do?

A: Pull fluid into the bloodstream from cells.

Q: What is a common isotonic fluid?

A: 0.9% NaCl (normal saline).

Q: What is another common isotonic fluid?

A: Lactated Ringer’s.

Q: What type of fluid is D5W initially considered?

A: Isotonic.

Q: What are examples of hypotonic fluids?

A: 0.45% NaCl and 0.225% NaCl, and dextrose 2.5% in water.

Q: What should be monitored closely with hypotonic fluids?

A: Neurologic status.

Q: What is an example of a hypertonic fluid?

A: 3% NaCl.

Q: What should be monitored with hypertonic fluids?

A: Blood pressure and lung sounds.

Q: Why must sodium imbalances be corrected slowly?

A: To prevent cerebral edema or osmotic demyelination syndrome.

Q: Where do colloids stay?

A: In the intravascular space.

Q: What pressure do colloids increase?

A: Oncotic pressure.

Q: Why are colloids less likely to cause edema?

A: They stay in the bloodstream longer.

Q: What is a natural colloid example?

A: Albumin

Q: What is diffusion?

A: Movement of molecules from high concentration to low concentration.

Q: What is osmosis?

A: Movement of water from low solute concentration to high solute concentration.

Q: What is active transport?

A: Movement against the concentration gradient using ATP.

Q: What does low plasma osmolality indicate?

A: Fluid overload.

Q: What does high plasma osmolality indicate?

A: Fluid deficit.

Q: What is hydrostatic pressure?

A: Pushing pressure.

Q: What is osmotic pressure?

A: Pulling pressure.

Q: What is first spacing?

A: Fluid in its normal location.

Q: What is second spacing?

A: Edema.

Q: What is third spacing?

A: Fluid trapped in nonfunctional spaces like ascites.

Q: What hormone increases water reabsorption?

A: ADH (antidiuretic hormone).

Q: Where does ADH act?

A: Kidneys.

Q: What triggers increased ADH release?

A: Increased osmolality (fluid deficit).

Q: What gland releases aldosterone?

A: Adrenal cortex.

Q: What does aldosterone cause?

A: Sodium and fluid retention.

Q: What triggers the RAAS system?

A: Low blood pressure or low kidney perfusion.

Q: What is angiotensin II?

A: A powerful vasoconstrictor.

Q: What is the end result of RAAS activation?

A: Increased blood pressure and fluid retention.

Q: What do ANP and BNP do?

A: Lower blood volume and blood pressure.

Q: What stimulates release of ANP and BNP?

A: Stretching of the atria from fluid overload.

Q: What GI conditions commonly cause fluid and electrolyte loss?

A: Vomiting, diarrhea, NG suction.

Q: What lab values often increase with fluid deficit?

A: BUN, hematocrit, urine specific gravity, serum osmolality.

Q: What happens to hematocrit in fluid overload?

A: It decreases.

Q: What causes hypovolemia?

A: Fluid loss greater than intake.

Q: What causes hypervolemia?

A: Fluid retention greater than loss.

Q: What are common manifestations of hypovolemia?

A: Tachycardia, hypotension, dry mucous membranes, poor skin turgor.

Q: What are common manifestations of hypervolemia?

A: Edema, crackles, hypertension.

Q: What are the major positively charged electrolytes (cations)

A: Sodium, potassium, calci, mg.

Q: What are common negatively charged electrolytes (anions)?

A: Cl, HCO3, phosphate.

Q: What commonly causes hyponatremia?

A: Vomiting, diarrhea diuretic drugs, fluid overload.

Q: What severe symptoms can occur with sodium imbalance?

A: Seizures and coma.

Q: What are common causes of hypokalemia?

A: Diuretics, vomiting, diarrhea, decrease intake.

Q: What are common causes of hyperkalemia?

A: Renal failure, potassium-sparing drugs, trauma massive tissue injury.

Q: What ECG change is classic for hyperkalemia?

A: Peaked T waves.

Q: What are symptoms of hypokalemia?

A: Weakness, arrhythmias, muscle cramps, constipation, alkalosis, confusion.

Q: What are symptoms of hyperkalemia?

A: Muscle twitches arrhythmias, peaked T waves, slowed reflexes.

Q: What medication stabilizes the heart in hyperkalemia?

A: Calcium gluconate

Q: What medication removes potassium through the GI tract?

A: Sodium polystyrene sulfonate

Q: Why is insulin given with dextrose in hyperkalemia?

A: Insulin shifts potassium into cells

Q: What newer medication treats hyperkalemia by binding potassium?

A: Sodium zirconium cyclosilicate

Q: How should IV potassium always be administered?

A: Diluted and infused slowly.

Q: What must be monitored during IV potassium administration?

A: Renal function and urine output.

Q: What IV potassium complication can occur in veins?

A: Phlebitis.

Q: What commonly causes hypocalcemia?

A: Hypoparathyroidism, vitamin D deficiency, renal failure.

Q: What commonly causes hypercalcemia?

A: Hyperparathyroidism and cancer.

Q: What is tetany?

A: Sustained muscle contraction.

Q: What are signs of hypocalcemia?

A: Tetany, Chvostek sign, Trousseau sign, hyperreflexia, seizures.

Q: Why is stridor dangerous in hypocalcemia?

A: It may indicate laryngeal tetany.

Q: What are symptoms of hypercalcemia?

A: Weakness, fatigue, hypertension, arrhythmias, kidney stones.

Q: What are symptoms of hypomagnesemia similar to?

A: Hypocalcemia.

Causes: alc use disorder and malnutrition.

Q: What are symptoms of hypermagnesemia similar to?

A: Hypercalcemia.

Causes: renal failure.

Q: What causes hyperphosphatemia?

A: Renal failure, tumor lysis syndrome, excessive phosphate intake.

Q: What causes hypophosphatemia?

A: Malabsorption and decreased intake.

Q: What is used to treat hyperphosphatemia?

A: Phosphate binders.

Q: What mineral does phosphate do the opposite as?

A: Calcium