Summer 2018
Exam #4 Material
Chapter 21 – IV Therapy and IV Medication Administration
Intravenous Therapy
o Administration of fluids, electrolytes, medications or nutrients via venous route.
o IV Therapy Is Used To:
o Expand intravascular volume
o Maintain fluid and electrolyte balance
o Correct an underlying imbalance in fluids or electrolytes
o Correct or prevent nutritional imbalances TPN
o Provide IV medication therapy
Types of Solutions
o Solutions are classified according to how they compare to the osmolality of blood serum
o Remember that blood serum normal osmolality is 280 – 295 mOsm/kg
o Classified As:
o Isotonic: the solutions has the same osmolality as our blood
o Hypotonic: the solutions has less the osmolality as our blood
o Hypertonic: the solution has more osmolality as our blood
Isotonic Solution
o Osmolality of 250 – 375mOsm/L
o Remain inside the intravascular compartments
o No fluid shifting occurs****hypothetically(test purposes) but in reality, bc of osmolality, shifting tends
to occur no net loss or gain from the ICF
o 1/3 to ½ of fluid stays in vasculature
o Expands fluid volume of ECF
o Ideal for pts with hypovolemia or hypotension
o Examples:
o 0.9% normal saline
o Lactated Ringer’s solution
Hypotonic Solution
o Osmolality lower than 250mOsm/L- 250 is the solute(particles) “less particles, less concentration, more water- in
the body, water ”
o Water moves out of blood vessel into the cells and interstitial tissue
o Used For:
o Patients with hypertonic dehydration (high osmolality)
o Hypernatremia
o Patients needing water replacement
o Examples:
o Water
o 5% dextrose and water (D5W)
o 0.45% saline (1/2NS) ½ of 0.9% saline
o D5 0.25% Saline
Hypertonic Solutions
o Osmolality of 375 mOsm/L or greater “more particles, more concentration, less water-”
o Initially raises the osmolality of ECF
o Water moves from ICF & interstitial compartments into vascular space draws water in
o Useful in Treatment Of:
o Hypotonic Dehydration
o Temporary treatment of hypovolemia, hyponatremia and shock
, o Hyponatremia
o Require frequent monitoring of BP, lung sounds, & serum Na+ levels
o Examples:
o Volume expanders (Dextran, Albumin, Hespan, Hetastarch)
o D10%W Dextrose metabolized ASAP then it becomes hypotonic, severe hypoglycemia, stopping TPN
suddenly
o D5% 0.9NS becomes isotonic as soon as Dextrose is metabolized
o D5% LR
o 3% hypertonic saline pts with increased intracranial pressure; pulling water from cerebral cells that will
go into the intravascular space; give very carefully; only given in an ICU setting
5% Dextrose in Water (D5W)
o Isotonic in bag, but physiologically (in the body) is hypotonic
o Provides 50 g/L of glucose, which is about 170 cal/L
o 5 grams of Dextrose per 100mL of fluid
o Indications and Considerations
o Provides free water only, no electrolytes
o Moves into ICF
o Increases renal solute excretion
o Used to replace water losses, glucose, and treat hypernatremia
Normal Saline (NS – 0.9% NS)
o Isotonic
o No calories, free water, or other electrolytes
o More NaCl than ECF excessive administration can result in elevated Na+ and Cl- levels
o Hyperkalemic Acidosis: can occur
o Clinical Uses
o Hyponatremia (mild only!)
o Treatment of shock
o Use with blood transfusions prime beforehand; this is the only acceptable fluid for this
o Fluid replacement for Diabetic Ketoacidosis (DKA) once it gets below 200, no NS
o Compatible with most medications
Lactated Ringer’s
o Isotonic
o More similar to plasma than NS
o Has less NaCl
o Has K,+ Ca 2+, lactate (metabolized to HCO3-)
o Does not provide calories
o Clinical Uses:
o Replenishes fluid and electrolyte for dehydration from nausea and vomiting, burns, wounds
o Has some incompatibilities with medications
o Post-surgery fluid post-op patients can get acidotic and the bicarb in LRs can counteract
this D5 ½ NS
o 5% dextrose in 0.45% saline
o Hypertonic in the bag; once it goes into the body, Dextrose is metabolized, so it changes to hypotonic
o Common maintenance fluid
o Same as 0.45% NaCl except provides 170 calories/L
o KCl often added for maintenance or replacement for hypokalemia
o Example: D5 1/2NS with 40 mEq KCl at 100 ml/hr
D10W
o Hypertonic in the bag
o Provides 100 g/L of glucose or 340 kcal/L
o 10 grams of dextrose in every 100mL
o No electrolytes
o Limit of dextrose concentration may be infused peripherally
, o Any fluid higher than 10% dextrose must be infused via central line to prevent shrinkage of RBCs
or adverse outcomes if IV infiltrates; anything higher than 10% Dextrose in peripheral, this can
be severely damaging, irritable, RBC will shrink, etc.
o If TPN has to be stopped, can experience hypoglycemia Give D10W
Plasma Expanders
o Stay in the vascular space and increase osmotic and/or oncotic pressure
o Colloids (protein solutions) increase both osmotic and oncotic pressures; big particles- keep fluid in the
vessels or pull fluid into the vessels
o Packed RBCs
o Albumin
o Plasma
o Dextran (complex synthetic sugar); high concentration; osmotic pull and oncotic pull (expand volume,
keep volume)
o Pulls additional fluid into the intravascular space
o Hetastarch (Hespan)
o Synthetic colloid works similarly to Dextran to expand plasma volume
Common IV Solutions - Review
o 0.9% Sodium Chloride
o Normal Saline or NS
o Isotonic
o Fluid won’t shift some will leak out, but not a true fluid shift
o D5%W- Isotonic in bag, hypotonic in body
o 5 grams per 100mL
o Physiologically hypotonic
o Fluid will shift from ECF to ICF
o Clinical Application: patient has a TBI and has severe cerebral edema, if given hypotonic IVF patient
will get worse; even more fluid in cells will not be a good thing!
o Lactated Ringers
o LR, Ringer’s Lactate
o Sodium, Chloride, Potassium, Lactate (metabolized into bicarb), water
o Isotonic
o Fluid won’t
shift
o 0.45% Sodium Chloride
o ½ NS
o Sodium, chloride, water
o Hypotonic
o Fluid will shift from ECF to ICF
o 5% of Dextrose in Lactated Ringers
o D5LR
o Sodium, Chloride, Glucose, Potassium… and water
o Hypertonic in the bag, isotonic in the body (once the dextrose is metabolized)
o Fluid will shift from ICF to ECF; fluid shift should stop (after dextrose is metabolized)
Real World Example: A patient s/p ex. lap. is transferred to the surgical unit with an order for LR at 125 ml/hr. Prior to
surgery a basic metabolic panel (BMP) was drawn:
o Na: 140 (normal 135-145)
o Cl: 106 (normal is 98-110)
o K: 4.5 (normal is 3.5-5)
Vital Signs:
o 135/79
o 105 BPM
o 22 resp/min
o 96.9 F
o 92% on 2 L 02 per NC