Diffusion and Tonicity (copy)

Intracellular Fluid (ICF) makes up what total % of the body’s water?

60%

Extracellular Fluid (ECF) makes up what total % of the body’s water?

40%

Number of particles (osmoles) per kilogram of solvent (Osm/kg).

Osmolality

Number of particles (osmoles) per liter of solution (Osm/L).

Osmolarity

The pressure exerted by blood on the capillary walls, driven by the heart's contraction and the volume of blood within the vessels.

Hydrostatic pressure

A type of osmotic pressure created by the presence of large, impermeable proteins (especially albumin) in the blood plasma. 

Colloid osmotic pressure/Oncotic pressure

Negative consequences relating to Fluids and electrolytes balance

• Fluid retention

• Impaired neuromuscular function

• Cardiac arrhythmia

• Impaired cerebral function

Positive consequences relating to Fluids and electrolytes balance

• Muscle WNL

• Clear Mentation

• Good skin turgor

The state of steady internal physical and chemical conditions maintained by living systems

Homeostasis

Example: 3% saline

Think: Crenated cell

Hypertonic

Example: 0.9% normal saline/Lactated ringers

Think: Normal Cell

Isotonic

Example: 0.45% normal saline (Half-normal saline)

Think: Swollen cell

Hypotonic

What cell transports do not require energy?

• Osmosis

• Diffusion

• Facilitated diffusion

What cell transport requires energy?

• Active transport

• Bulk transport

A way that cells move large particles or large amounts of material across the cell membrane.

Phagocytosis

Form of active transport

Bulk transport

Example of bulk transport?

Phagocytosis

What solution is Isotonic until inside the body?

D5W

What happens when D5W is inside the body?

The glucose is metabolized and then it becomes Hypotonic

Do not give D5W to Who?

• Infants

• Head injury patients

Why would you not give D5W to Infants and Head injury patients?

May cause Cerebral edema

What is the go to fluid for rehydration and maintenance fluids?

Normal saline

Normal saline is useful for what?

• IV hydration

• Maintenance

• Hypotension

• Sepsis

• Shock

Use caution when administering Normal saline for:

• CHF

• ESRD

• SIADH

• Large quantities

What is an alternative to Normal saline?

Lactated ringers

What are lactated ringers useful for?

• Dehydration

• Maintenance

• Ongoing fluid loss

• Sepsis

• Pancreatitis

• Burns

• Surgical patients 

Avoid Lactated ringers in

• Severe renal/Liver failure

• Hyperkalemia

• Hypercalcemia

• Metabolic acidosis

• Blood transfusions

Technically considered isotonic, but it acts as a hypotonic fluid. This is because the glucose is metabolized quickly, leaving free water which is hypotonic

D5W

D5W is useful for what?

• Mixing with meds

• Hypernatremia/Overly corrected hyponatremia

Avoid D5W with what?

• Hyponatremia

• Hypokalemia

• Head trauma

• Diabetes

• Burns

• Liver failure

What is Half normal saline useful for?

• Maintenance fluids

• Hyperosmolar Hyperglycemic State (HHS)

• DKA

Avoid half normal saline with what?

• Hyponatremia

• Head trauma

• Burns

• Liver failure

• Faster infusion rates

What are hypertonic solutions like 3% normal saline useful for?

• Severe hyponatremia

• Increased Intracranial pressure

Avoid Hypertonic fluids with?

• Anything aside from:

  • Severe hyponatremia

  • Increased ICP

Laboratory Tests for Evaluating Fluid Status

• BUN

• Creatinine

• Glucose

• Urea

• Uric acid

When urine osmolality is measured with this, it becomes the most reliable indicator of urine concentration?

Serum osmolality

In healthy adults, normal serum osmolality is?

275 to 290 mOsm/kg

Urine with a specific gravity of 1.)_____________ is very dilute or high in water content, whereas urine with a specific gravity of 2.)_______ is very concentrated or low in water content.

1. 1.005

2. 1.030

The normal range of BUN is?

10 to 20 mg/dL (3.6 to 7.2 mmol/L).