fluids flashcards

What is the body composed of that must be in balance?

Fluids, electrolytes, and acid-base components.

Why is balance of fluids, electrolytes, and acid-base components important?

Most diseases can disrupt this balance.

What percentage of the brain is water?

75%.

What is the water percentage in blood?

83%.

What percentage of muscles is made up of water?

75%.

What is the water percentage in bones?

22%.

What are the key functions of water in the body?

Regulates temperature, moistens oxygen, helps convert food to energy, removes waste, cushions organs, and aids nutrient absorption.

What do electrolytes help with in the body?

Transmission of nerve impulses and muscle contraction.

Why is acid-base balance crucial?

To maintain a narrow pH range to avoid disrupted biological processes.

What are the three systems that regulate pH?

Buffers, respiratory system (CO2), renal system (HCO3-).

What does pH indicate?

Hydrogen ion concentration; low pH means acidic (more H+), and high pH means alkalotic (less H+).

What are the normal pH values of body fluids for urine?

5.0–6.0.

What is the normal gastric pH value?

1.0–3.0.

What is the normal arterial blood pH range?

7.35–7.45

What is the pH range for venous blood and cerebrospinal fluid (CSF)?

7.32–7.37.

What is the pancreatic fluid pH range?

7.8–8.0.

What are the major fluid compartments in the body?

Intracellular Fluid (ICF) and Extracellular Fluid (ECF).

What are the major ions found in intracellular fluid (ICF)?

High K+, moderate Mg++, small amounts of Na+, Ca++, Cl-, HCO3-, phosphate.

What are the major ions found in extracellular fluid (ECF)?

High Na+, Cl-.

What is the total body water (TBW) percentage for newborns?

75%.

What is the TBW percentage for children?

60–65%.

What is the TBW percentage for adults?

50–60%.

What is the TBW percentage for older adults?

Lower than the percentages for younger age groups.

What is diffusion?

Particles move from high to low concentration.

What is osmosis?

Water movement across a membrane from lower solute concentration to higher solute concentration.

What is tonicity?

The osmotic effect on cells; isotonic means no change, hypotonic leads to cells swelling, hypertonic leads to cells shrinking.

How much water is recommended daily?

100 mL per 100 calories, more with fever/exercise.

How does the body protect extracellular fluid (ECF) volume?

Through vasoconstriction, heart rate changes, and sodium/water balance.

What causes edema?

Increased hydrostatic pressure, decreased oncotic pressure, increased permeability, lymph obstruction.

What are conditions that can cause edema?

CHF, renal/liver failure, DVT, pregnancy, lymph obstruction, malnutrition, inflammation.

What are the types of edema?

Localized, general, dependent, pitting.

How to assess for edema?

Daily weight, visual checks, measuring limbs, pitting test.

What are some treatments for edema?

Elevate limbs, compression, reduce salt intake, diuretics.

What are the mechanisms that regulate water balance?

Thirst (intake), ADH (output).

How can one assess for body fluid loss?

Weight, blood pressure, heart rate, refill time, volume signs, history.

Where are electrolytes found in the body?

In both intracellular fluid (ICF) and extracellular fluid (ECF), but concentrations differ.

What is the main intracellular fluid (ICF) electrolyte?

Potassium (K+).

What are the main extracellular fluid (ECF) electrolytes?

Sodium (Na+), chloride (Cl-), and bicarbonate (HCO3-).

What systems regulate sodium?

Kidneys, sympathetic nervous system (SNS), renin-angiotensin-aldosterone system (RAAS), ADH, atrial natriuretic peptide (ANP).

What are the normal Na+ levels?

135–145 mEq/L.

How is sodium regulated?

By aldosterone and water volume.

aldosterone regulates sodium and potassium levels in the body.

What mechanisms control water balance?

Baroreceptors, RAAS, ADH, ANP.

What roles does sodium play in the body?

Osmotic regulation, nerve impulses, acid-base balance.

What is the role of chloride in the body?

Main extracellular fluid anion, maintains neutrality, follows Na+.

What does aldosterone do?

Reabsorbs Na+ and secretes K+, helps regulate blood volume.

What does ADH do?

Reabsorbs water in response to high osmolality or low volume.

What defines hypernatremia?

Na+ > 145 mEq/L, causes dehydration.

What are the signs of hypernatremia?

Seizures, twitching.

What are the signs of water deficit?

Low blood pressure, weak pulse, dry mucosa.

How is water deficit treated?

With fluids.

What is hyponatremia?

Serum sodium < 135 mEq/L.

What is the mechanism behind hyponatremia?

Sodium deficit leads to plasma hypoosmolality and cellular swelling.

What types of hyponatremia exist?

Hypovolemic, Euvolemic, Hypervolemic.

What are some signs and symptoms of hyponatremia?

Lethargy, headache, confusion, apprehension, seizures, coma.

How is hyponatremia treated?

By treating the underlying disorder; water restriction.

What are the signs of hypernatremia?

Thirst, polydipsia, oliguria/anuria, dry mucous membranes, low turgor, headache, agitation, tachycardia, weak pulse.

What is the effect of hypernatremia on cells?

Cells shrink.

What is the normal potassium level in extracellular fluid (ECF)?

3.5–5.0 mEq/L.

What is the potassium level in intracellular fluid (ICF)?

140–150 mEq/L.

What regulates potassium levels?

Na+/K+ pump, aldosterone, insulin, epinephrine, pH changes.

What are the functions of potassium in the body?

Nerve conduction, cardiac rhythm, muscle contraction, glycogen storage.

What is the diagnostic approach for potassium imbalances?

History, physical examination, potassium levels, ECG.

What are some treatments for potassium imbalances?

Calcium to antagonize K+ effects, sodium bicarbonate, insulin + glucose, increase renal excretion and reduce intake.

What is hypokalemia?

K+ < 3.5 mEq/L.

What causes hypokalemia?

Reduced intake, increased entry into cells, loss via GI/renal/skin.

What are the signs and symptoms of hypokalemia?

Decreased excitability, confusion, weakness, cramps, atony, dysrhythmias, postural hypotension, U wave on ECG.

How is hypokalemia treated?

With oral/IV potassium replacement.

What is hyperkalemia?

K+ > 5.0 mEq/L.

What causes hyperkalemia?

Intake, ICF to ECF shift, renal failure, trauma, acidosis, digitalis overdose.

What are the mild signs of hyperkalemia?

Tingling, restlessness, diarrhea, tall T waves.

What are the severe signs of hyperkalemia?

Weakness, paralysis, dysrhythmias, wide QRS, prolonged PR interval.

How is hyperkalemia treated?

Calcium gluconate, insulin + glucose, buffered solution, dialysis.

What does parathyroid hormone (PTH) do?

Increases calcium (Ca2+) levels.

What effect does vitamin D have on calcium and phosphate?

Increases absorption.

What does calcitonin do?

Decreases calcium (Ca2+) levels.

What is the serum calcium reference range?

Ionized: 5.5–5.6 mg/dL.

Where is calcium primarily located in the body?

99% in bone, 1% in plasma/cells.

What are the functions of calcium?

Bone/teeth structure, blood clotting, hormone secretion, receptor function, muscle contraction.

What are the forms of calcium in extracellular fluid (ECF)?

Protein-bound (40%), complexed (10%), ionized (50%).

What defines hypocalcemia?

Ca2+ < 9.0 mg/dL.

What causes hypocalcemia?

Low intake/absorption, low PTH/vitamin D, transfusions.

What are the signs and symptoms of hypocalcemia?

Spasms, Chvostek's sign, Trousseau's sign, tetany, convulsions.

How is hypocalcemia treated?

With calcium replacement and decreased phosphate.

What defines hypercalcemia?

Ca2+ > 10.5 mg/dL.

What causes hypercalcemia?

Hyperparathyroidism, bone metastasis, vitamin D excess, immobilization, acidosis.

What are the signs and symptoms of hypercalcemia?

Weakness, stones, constipation, heart block.

How is hypercalcemia treated?

With phosphate, IV normal saline, bisphosphonates, calcitonin, denosumab.

What is the serum phosphate reference range?

2.5–4.5 mg/dL.

What are the functions of phosphate in the body?

ATP production, buffering, DNA/RNA structure, red blood cell oxygen delivery.

What is the relationship between phosphate and calcium?

Inverse relation.

What defines hypophosphatemia?

<2.0 mg/dL.

What causes hypophosphatemia?

Malabsorption, antacids, alcoholism, refeeding syndrome.

What are the signs and symptoms of hypophosphatemia?

Soft bones, muscle weakness, platelet dysfunction, leukocyte change, rickets.

How is hypophosphatemia treated?

By treating the cause and replacing phosphate.

What defines hyperphosphatemia?

4.7 mg/dL.

What causes hyperphosphatemia?

Renal failure, phosphate enemas/laxatives, cell destruction.

What are the signs and symptoms of hyperphosphatemia?

Similar to hypocalcemia, with soft tissue calcification.

How is hyperphosphatemia treated?

With aluminum hydroxide, dialysis, and treating the underlying cause.

What are the functions of magnesium in the body?

ATP reactions, protein/nucleic acid synthesis, neuromuscular control.

What defines hypomagnesemia?

<1.8 mg/dL.