NUR 2063 FLUID DISTRIBUTION REVIEW

NUR 2063 FLUID DISTRIBUTION REVIEW What is osmosis? The shifting of water from one fluid compartment to another via a semi-permeable membrane. Water will always want to move from an area with a lesser concentration of solutes to an area with a greater concentration of solutes. "Concentration calls!" What is osmolality? A measurement of how concentrated a compartment is (the proportion of solutes-to-water that is in a compartment's fluid). Clinically we can measure the solute concentration of the blood by doing a serum osmolality and have an idea about what fluid shifts to anticipate since osmolality (concentration) rules osmosis. What is tonicity? the "saltiness" of a fluid or how much of it is made of salt. This is interchangeable with the term salinity. The normal tonicity (salinity) of the blood is 0.9% What is osmotic pressure? The pressure exerted by all of the solutes in a compartment. It correlates with osmolality. Remember, concentration calls! What are some common causes for pathologic water loss? inadequate intake (patient too sick to drink) increased output (vomiting, diarrhea, increased urination) end result: dehydration or fluid volume deficit What are common symptoms of dehydration or fluid volume deficit? dry mucuous membranes, poor skin turgor, sunken eyes, sunken fontanels in babies, oliguria, increased urine concentration, low BP, acute CNS changes, high serum osmolality. Which body systems compensate for fluid volume deficit? RAAS and ADH secretion