m3 fluid and electrolytes & safety centered care

60-40-20 Rule of body weight

60% is water, 40% is intracellular fluid, 20% is extracellular fluid.

Intracellular fluid (ICF) compartment

The fluid compartment contained entirely within the cells.

Extracellular fluid (ECF) compartment

All body fluid located outside of the cells.

Two sub-compartments of extracellular fluid (ECF)

Interstitial fluid and intravascular fluid.

Pediatric body weight water percentage

75% to 80% of body weight.

Why older adults are prone to dehydration

Decreased total body water, decreased renal function, and diminished thirst perception.

Isotonic solution

A solution with the same solute concentration as blood.

Hypertonic solution effect on cells

It causes water to move out of cells, making them shrink.

Hypotonic solution effect on cells

It causes fluid to move into cells, potentially making them burst.

Filtration

Fluid movement through a membrane caused by hydrostatic pressure differences.

Hydrostatic pressure

The water-pushing force that pushes water outward from a confined space.

Diffusion

Free movement of particles from an area of higher to lower concentration.

Minimum daily urine output for toxic waste excretion

400 to 600 mL per day.

Antidiuretic hormone (ADH) primary function

Tells the kidneys to reabsorb water and sodium, slowing down urination.

Stimulants for ADH release

Low sodium, decreased blood volume, or increased body fluid osmolarity.

Renin secretion trigger

Sensed low blood volume or perfusion pressure by the kidneys.

ACE inhibitors mechanism of action

Block angiotensin II production, causing vasodilation and increased water excretion.

Fluid volume change of 1 pound of body weight

Approximately 500 mL of fluid.

Normal serum sodium level

136 to 145 mmol/L.

Normal serum potassium level

3.5 to 5.0 mEq/L.

Normal serum calcium level

9.0 to 10.5 mg/dL.

Normal serum phosphorus level

3.0 to 4.5 mg/dL.

Normal serum magnesium level

1.3 to 2.1 mg/dL.

Relationship between calcium and phosphorus levels

They exist in a balanced reciprocal relationship.

Hormone that increases blood calcium concentration

Parathyroid Hormone (PTH).

Hormone that deposits calcium into bones

Calcitonin.

Primary function of magnesium in muscles

Keeps law and order by regulating nerve function and muscle contraction.

Lactated Ringer's (LR) components

Normal saline with potassium, calcium, and lactate.

Primary risk of excessive Lactated Ringer's administration

Fluid and sodium overload leading to peripheral or pulmonary edema.

D5W tonicity behavior

Isotonic in the bag, but becomes hypotonic once dextrose is metabolized.

Why D5W should not be used for resuscitation

It can cause hyperglycemia.

0.9% Sodium Chloride (Normal Saline) primary uses

Shock, hyponatremia, blood transfusions, resuscitation, and fluid challenges.

0.45% Sodium Chloride (Half-Normal Saline) classification

Hypotonic solution used for water replacement and maintenance.

Contraindications for 0.45% Sodium Chloride

Patients with liver disease, trauma, or burns.

Clinical indication for Dextrose 5% in half-normal saline in DKA

Used when blood glucose falls below 250 mg/dL to prevent hypoglycemia.

Main risk of Dextrose in 5% normal saline

Fluid overload, especially in patients with cardiac or renal disease.

Indication for 3% Sodium Chloride solution

Severe dilutional hyponatremia or severe sodium depletion.

Key precaution for 3% Sodium Chloride administration

Administer cautiously and monitor closely to prevent pulmonary edema.

Skin turgor assessment location in older adults

Over the sternum or on the forehead.

Minimum hourly urine output rate in fluid volume deficit

At least 0.5 mL/kg/hr.

Frequency of assessing fluid overload patients for pulmonary edema

At least every 2 hours.

First priority assessment when muscle weakness is present

Check respiratory effectiveness.

Maximum recommended infusion rate for IV potassium

5 to 10 mEq/hour, never exceeding 20 mEq/hour.

Recommended dilution ratio for IV potassium administration

No greater than 1 mEq per 10 mL of solution.

Action if IV potassium infiltration is suspected

Stop infusion immediately, remove venous access, and notify the provider.

Why women have less total body water than men

Women have more body fat and less muscle mass.