Medication Administration

3-to-1 Replacement Rule

- 3mL of isotonic crystalloid solution is needed to replace 1mL of a Pt blood - This amount is needed because approx. 2/3's of the infused isotonic crystalloid solution will leave the vascular spaces in about 1 hour. - The 2/3's of infused crystalloids is either absorbed into the interstitial space or excreted

Colloid Solutions

- Contain proteins that are too large to pass out of the capillary membranes, so the solutions remain in the vascular system. - The large protein molecules give colloid solutions a high osmolarity. As a result, they draw fluid from the interstitial and intracellular compartments into the vascular compartments - Work well in reducing edema (eg, Pulmonary Edema, or Cerebral Edema) while expanding the vascular compartment - Rarely used in prehospital setting other than Critical Care inter-facility transports. - Ex: Albumin, Dextran, Plasmanate, and Hetastarch (Hespan) -

Based on dissolved components, or makeup, IV solutions are categorized as either...

- Crystalloid - Colloid

Crystalloid Solutions

- Dissolved crystals (eg, salts or sugars) in water - The ability to cross membranes and alter fluid levels makes them the best choice for prehospital care of injured patients who need fluid replacement - Crystalloid solutions cannot carry oxygen. Fluid boluses should be administered as appropriate based on the working diagnosis to maintain perfusion (ie, radial pulses, adequate mental status) but not to restore blood pressure to the pt's normal level

Isotonic Solutions

- Have almost the same osmolarity as serum and other body fluids. - As a consequence, isotonic solutions expand the contents of the intravascular compartment w/out shifting fluid to or from other compartments, or changing cell shape --- an important consideration when caring for hypotensive or hypovolemic pt's. - Be careful of fluid overloading - Normal Saline (0.9%) - Lactated Ringers: Generally used in the field for pt's who have significant blood loss. Contains lactate, which is metabolized in the liver to form bicarbonate --- the key buffer that combats the intracellular acidosis associated w/ severe blood loss. Should not be given to pt's w/ liver problems, because they cannot metabolize the lactate. Not shown an overwhelming benefit over normal saline for fluid resuscitation. Contraindicated w/ blood transfusions and various medication infusions - D5W (5%dextrose in water) is an isotonic solution while it is in the bag. Once it is administered the dextrose is quickly metabolized, and the solution becomes hypotonic. Rarely administered by itself. Usually administered when preparing med infusions such as dopamine (Intropin) or amiodarone (Cordarone)

Hypotonic Solutions

- Lower concentration of sodium (osmolarity) than the cell's serum - When this fluid is placed in the vascular compartment, it begins diluting the serum. - The serum osmolarity becomes less than that of the interstitial fluid; water is pulled from the vascular compartment into the interstitial fluid compartment, then from the interstitial fluid and into the cells. - Cells eventually swell and possibly burst from the increased intracellular osmotic pressure. - Hypotonic solutions hydrate the cells while depleting the vascular compartment. - May be needed for dialysis when diuretic therapy dehydrates the cells - May be used for hyperglycemic pt's w/ DKA where high serum glucose levels draw fluid out of the cells and into the vascular and interstitial compartments - Hypotonic solutions can cause a sudden fluid shift from the intravascular space to the cells, leading to cardiovascular collapse and increased ICP from shifting fluid into the brain cells - For pt's w/ burns, trauma, malnutrition, or liver disease is also hazardous because these pt's are at risk for developing Third Spacing, an abnormal fluid shift into the serous linings.

Inhaled Medications

- MDI's (Metered Dose Inhalers - Spacers for MDI's - Small Volume Nebulizers

Hypertonic Solutions

- Osmolarity higher than that of serum, meaning that the solution has a higher ionic concentration than serum and pulls fluid and electrolytes from the intracellular and interstitial compartments into the intravascular compartment. - The danger is that the cells may collapse from the increased extracellular osmotic pressure. - Hypertonic solutions shift body fluids into the vascular spaces and help stabilize BP, increase urine output, and reduce edema. - Rarely used in prehospital setting, more in inter-facility transports or hospital. - Often the term "hypertonic" is used to refer to solutions that contain high concentrations of proteins, these proteins have the same effect on fluid as sodium. - Should not be given to pt's w/ DKA or others at risk of cellular dehydration - Use with caution in any pt w/ impaired heart or kidney functions - May see hypertonic solution 3% sodium chloride for inter-facility transports for pt's w/ severe TBI's. Used as a temporizing measure to draw out fluid in an effort to reduce ICP until pt can be taken into neurosurgery.

Enteral Medications

- Sublingual: NItroglycerin, Nitrolingual Spray - Buccal (Mucous membranes in cheeks): Oral Glucose - Rectal: - NG/OG:

Parenteral Medications

- Topical Route: Nitroglycerin Ointment - Endotracheal Route : NAVELO (Narcan, Atropine, Vasopressin, Epinephrine, Lidocaine, Oxygen) - Intranasal Route: - Injection Route: Subcutaneous, Subdermal, Intramuscular, Intravenous

Sodium

- Used as the benchmark to calculate a solution's tonicity - The concentration of sodium in the cells of the body is approx. 0.9% - Altering the concentration of sodium in the IV solution can move the body water into or out of any fluid compartment in the body