Fluids and Electrolytes - Ch. 45 Flashcards
What are the 3 main components of total body water?
Intracellular fluid (ICF) 67%
Interstitial fluid (IF) 25%
Plasma volume (PV) 8%
IF + PV = ECF (33%)
What are the components of ECF?
Interstitial fluid
Blood (Plasma and cells)`
What determines the distribution of fluid in ECF?
Bulk flow
-Starling forces
What pressures need to be balanced during fluid balance?
Hydrostatic pressure, aka blood pressure
Colloid osmotic pressure due to plasma proteins
What is equal to maintain water balance?
Water intake = Water loss
What can occur when fluid is out of balance?
Edema
Dehydration
Fluid loss
Why are IV fluids administered?
Dehydration
Electrolyte imbalances
Blood component deficiencies
Nutrition
What are the types of IV fluids?
Crystalloids
Colloids
Blood and blood products
What are Crystalloids?
Solutions (contain water) with
-electrolytes (Na, K, Cl)
-small molecules (glucose, lactate)
Crystalloids DO NOT contain what?
Proteins/large molecules
Examples of crystalloids?
Normal saline
Hypertonic saline
Half normal saline
Lactated RInger (LR)
D5W
Normosol/Plasmalyte
Osmolarities of Normal saline?
Na 154
Cl 154
K 0
Osmolarities of Hypertonic saline?
Na 513
Cl 513
K 0
Osmolarities of Lactated Ringer (LR)?
Na 130
Cl 109
K 4
Osmolarities of D5W?
Na 0
Cl 0
K 1
What percentatge of sodium chloride is in each kind of saline?
Normal saline 0.9% NaCl
Half normal saline 0.45% NaCl
Hypertonic saline 3% NaCl
In what ways are crystalloids used as replacement/maintenance fluids?
Compensate for insensible fluid losses (eg, NS)
To replace fluids (eg NS)
To manage specific fluid and electrolyte disturbances (eg Ringerβs lactate)
Promote urinary flow (eg NS)
Expand plasma volume (eg 3% NaCl)
What indications require Crystalloids?
Acute liver failure
Acute nephrosis
Burns
Hypovolemic shock
Renal dialysis
Normal saline-based fluids (0.9% NaCl) are used with the administration of which products?
Blood cell products
What adverse effects are associated with Crystalloids?
Edema (Peripheral or pulmonary)
Dilute plasma proteins
-Short-lived effects, lots of other effects
How do crystalloids cause edema?
Fluid overload
How do colloids work?
Increase colloid osmotic pressure (COP)
-Move fluid from the interstitial compartment to the plasma compartment
Plasma volume expanders -restore BP
What do colloids initiate?
Diuresis
e.g, removal ascites in patients with portal hypertension
Examples of colloids?
Dextran 40 or 70
Hetastarch/hydroxyethyl starch (HES)
Modified gelatin
Albumin (human donors)
What are Dextran 40 or 70?
BIG glucose polymers
What are Hetastarch/hydroxyethyl starch (HES)?
Synthetic and derived from cornstarch
What indications require colloids?
Trauma
Burns
Sepsis
Hypovolaemic shock
What do colloids contain that crystalloids do not?
Proteins/large molecules
What fluids are more expensive, crystalloids or colloids?
Colloids
What adverse effects are associated with colloids?
They are usually safe
-some concerns in renal failure
What disadvantages are associated with colloids?
May cause altered coagulation -bleeding
No oxygen-carrying capacity
What are the most expensive and least available fluids?
Blood and blood products
-require human donors
What are some examples of blood/blood product fluids?
Whole blood
RBC products carry oxygen
Increase the supply of various products e.g, clotting factors from plasma
Platelets
What are packed RBCs and whole blood used for?
Increase oxygen-carrying capacity
-anemia
-substantial hemoglobin deficits
-blood loss >25% of Total blood volume