Fluid and Electrolytes
____Intracellular Fluid________ (fluid inside the cell)= 70% of total body water/40% of body weight
____Extracellular Fluid_________(fluid outside the cell)= 30% of total body water/20% of body weight
1. Interstitial (around the cells) = 75% (excess = edema)
2. Intravascular (in the blood vessels) = 25%
3. Transcellular (cerebrospinal, pericardial, synovial, intraocular & pleural
fluids)=minor amounts. GI fluids *contain electrolytes
Daily I&O is approximately __2600_________ ml/day
Sources of Fluid Gain Sources of Fluid Loss
Liquids (1500 ml) Sensible : Urine (1500 ml)
Solid foods (800 ml) Feces (100 ml)
Water of oxidation (300 ml) Insensible: Skin (600 ml)
Lungs (400 ml)
, Fluid & Electrolyte Movement
Fluids move throughout the body by going back and forth across a cell’s semipermeable membrane.
PASSIVE = no energy required (diffusion, osmosis and filtration)
Diffusion: passive transport –___solutes__________move from an area of higher concentration
to an area of lower concentration
Capillary Filtration: movement of __fluid_____through capillary walls through hydrostatic pressure –
blood flows from arterial (high pressure) to venous (low pressure); balanced by plasma colloid osmotic
pressure.
Colloid osmotic pressure: pressure from proteins such as albumin that cause reabsorption of fluid and
solutes. Increased concentration = ____increased_________osmotic pressure.
Osmosis: passive movement of __fluid_______across a membrane from an area of lower solute
concentration to an area of higher solute concentration.
Active Transport: requires ATP to move ___solutes________ from an area of low concentration to an
area of higher concentration. Ex. Sodium-potassium pump
, Important Terms:
Osmolality/Tonicity = concentration of solutes providing pressure in body fluid
Isotonic = _same_____tonicity as the blood
Hypotonic = __less_____osmolality than blood = water enters cells
Hypertonic = ___more____osmolality than blood = water enters vascular space
Crystalloids = solutes that readily dissolve (i.e. electrolytes)
Colloids = larger molecules that do not readily dissolve (proteins)
____Intracellular Fluid________ (fluid inside the cell)= 70% of total body water/40% of body weight
____Extracellular Fluid_________(fluid outside the cell)= 30% of total body water/20% of body weight
1. Interstitial (around the cells) = 75% (excess = edema)
2. Intravascular (in the blood vessels) = 25%
3. Transcellular (cerebrospinal, pericardial, synovial, intraocular & pleural
fluids)=minor amounts. GI fluids *contain electrolytes
Daily I&O is approximately __2600_________ ml/day
Sources of Fluid Gain Sources of Fluid Loss
Liquids (1500 ml) Sensible : Urine (1500 ml)
Solid foods (800 ml) Feces (100 ml)
Water of oxidation (300 ml) Insensible: Skin (600 ml)
Lungs (400 ml)
, Fluid & Electrolyte Movement
Fluids move throughout the body by going back and forth across a cell’s semipermeable membrane.
PASSIVE = no energy required (diffusion, osmosis and filtration)
Diffusion: passive transport –___solutes__________move from an area of higher concentration
to an area of lower concentration
Capillary Filtration: movement of __fluid_____through capillary walls through hydrostatic pressure –
blood flows from arterial (high pressure) to venous (low pressure); balanced by plasma colloid osmotic
pressure.
Colloid osmotic pressure: pressure from proteins such as albumin that cause reabsorption of fluid and
solutes. Increased concentration = ____increased_________osmotic pressure.
Osmosis: passive movement of __fluid_______across a membrane from an area of lower solute
concentration to an area of higher solute concentration.
Active Transport: requires ATP to move ___solutes________ from an area of low concentration to an
area of higher concentration. Ex. Sodium-potassium pump
, Important Terms:
Osmolality/Tonicity = concentration of solutes providing pressure in body fluid
Isotonic = _same_____tonicity as the blood
Hypotonic = __less_____osmolality than blood = water enters cells
Hypertonic = ___more____osmolality than blood = water enters vascular space
Crystalloids = solutes that readily dissolve (i.e. electrolytes)
Colloids = larger molecules that do not readily dissolve (proteins)
