NURS 5315 Module 2
Osmolality
The concentration of a solution (osmoles of solute particles per kilogram)
Osmosis
Movement from less concentration to higher concentration
Osmotic Pressure
pressure that must be applied to prevent osmotic movement across a selectively permeable membrane
Hydrostatic Pressure
Pressure exerted by a volume of fluid against a wall, membrane, or some other structure that encloses
the fluid.
Oncotic Pressure
The osmotic pressure in the blood vessels due only to plasma proteins (primarily albumin) --> causes
water to rush back into capillaries at end.
Effective Arterial Blood Volume
The amount of blood within the arterial space- ECF changes will cause changes in the EABV in the same
direction the adequacy of the arterial blood volume to "fill" the capacity of the arterial vasculature.
, Antidiuretic Hormone
NON-diuretic hormone, retains fluids. Secreted when plasma osmolality increases or circulating blood
volume decreases.
Renin Angiotensin Aldosterone System
A hormone system that regulates blood pressure and fluid and electrolyte balance, as well as systemic
vascular resistance
Natriuretic Hormones
Hormones (atrial and brain natriuretic peptides) are released when there is an increase in transmural
arterial pressure caused by increased intraatrial volume (heart failure). ANP &BNP increase sodium and
water excretion by the kidneys, this lowers blood volume and BP.
Intravascular (extracellular)
Pattern of Fluid Shifts
1) Capillary hydrostatic pressure (blood pressure) facilitates the outward movement of water from the
capillary to the interstitial space.
2) Capillary (plasma) oncotic pressure osmotically attracts water from the interstitial space back into the
capillary.
3) Interstitial hydrostatic pressure facilitates the inward movement of water from the interstitial space
into the capillary.
4) Interstitial oncotic pressure osmotically attracts water from the capillary into the interstitial space.
Osmolality
The concentration of a solution (osmoles of solute particles per kilogram)
Osmosis
Movement from less concentration to higher concentration
Osmotic Pressure
pressure that must be applied to prevent osmotic movement across a selectively permeable membrane
Hydrostatic Pressure
Pressure exerted by a volume of fluid against a wall, membrane, or some other structure that encloses
the fluid.
Oncotic Pressure
The osmotic pressure in the blood vessels due only to plasma proteins (primarily albumin) --> causes
water to rush back into capillaries at end.
Effective Arterial Blood Volume
The amount of blood within the arterial space- ECF changes will cause changes in the EABV in the same
direction the adequacy of the arterial blood volume to "fill" the capacity of the arterial vasculature.
, Antidiuretic Hormone
NON-diuretic hormone, retains fluids. Secreted when plasma osmolality increases or circulating blood
volume decreases.
Renin Angiotensin Aldosterone System
A hormone system that regulates blood pressure and fluid and electrolyte balance, as well as systemic
vascular resistance
Natriuretic Hormones
Hormones (atrial and brain natriuretic peptides) are released when there is an increase in transmural
arterial pressure caused by increased intraatrial volume (heart failure). ANP &BNP increase sodium and
water excretion by the kidneys, this lowers blood volume and BP.
Intravascular (extracellular)
Pattern of Fluid Shifts
1) Capillary hydrostatic pressure (blood pressure) facilitates the outward movement of water from the
capillary to the interstitial space.
2) Capillary (plasma) oncotic pressure osmotically attracts water from the interstitial space back into the
capillary.
3) Interstitial hydrostatic pressure facilitates the inward movement of water from the interstitial space
into the capillary.
4) Interstitial oncotic pressure osmotically attracts water from the capillary into the interstitial space.
