Exam 3 Flashcards
what is an emulsion?
two phase systems in which one liquid is dispersed throughout another in the form of small droplets
define emulsification
added energy through trituration or homogenization creating small droplets of one liquid phase in another and a static charge around those droplets
define emulsifying agents
promotes the formation of droplets (micelles) and their charge based seperation (basically promotes formation of emulsion)
creaming
what happens?
can it be fixed?
migration (surfacing or settling) of droplets
yes: can be fixed by shaking
cracking or coalescence
what happens?
can it be fixed?
merging of droplets, causing a separation of the phases
no it cannot be fixed. needs to be discarded
what are the 2 phases of an emulsion.
what is each phase composed of
internal phase: droplets, micelles
external phase: suspension medium
two type of emulsion
Water in oil (w/o)
Oil in water (o/w)
water in oil emulsion.
what is it composed of
droplets of hydrophilic liquid (possibly containing water soluble drug) in a lipophilic suspension medium
oil in water
what is it composed of
droplets of lipophilic liquid (possibly containing fat soluble drugs) in an aqueous suspension medium
emulsions for ingestion
where are the active ingredients usually dissolved or suspended?why?
in the internal phase because they can hidden from the taste buds. increases pt compliance if it the drug tastes bad
emulsions for external use
where are the active ingredients usually dissolved or suspended? why?
in the external phase. want max bioavailability, which will occur in the external phase.
where phase of emulsions are flavoring agents usually found in? why?
eternal phase because that is the phase that is in contact with the pts taste buds
is the ratio of oil to water always an indicator of o/w or w/o emulsions?
no
what indicated whether an emulsion is w/o or w/o
order of incorporation and the chemical natural of the ingredients
identification tests for emulsions
drop test( drop dissolution test)
Principle:
test:
result:
drop test( drop dissolution test)
Principle: all emulsions are easily miscible with their continuous/ external phase
test: Add drop of water or oil to an emulsion
results:
if sample is easily diluted in water OR does not dissolve in oil, it is an O/W emulsion
if sample is easily diluted in oil OR dose not dissolve in water, it is an W/O emulsion.
identification tests for emulsions
electrical conductivity test
Principle:
test:
result:
electrical conductivity test
Principle: water is good conductivity of electricity, hence an emulsion in which water forms a continuous phase acts as a conductor.
test: a small low striking voltage neon lamp connected in series with a bayonet fitting plug and two electrodes Eg. Two-piece of copper wire. Dip these electrodes in a sample emulsion, apply the Current and observe the results.
result:
- w/o
a. Pass: if it doesn’t conduct electricity
b. fail: if it does conduct electricity - o/w
a. pass: if it does conduct electricity
b. fail:if it doesn’t conduct electricity
what is the viscosity of the emulsion due to
micelle diameter and weak hydrogen bonding between micelles
how do micelles form
in o/w, micelles form as spears with polar head groups facing the outside and non polar chain facing inside
w/o, it is the opposite
examples of emulsifiers
Acacia Lecithin polysorbate 80, tween 80 alcohol (s) Pluronic F68
routes of administration for emulsions
topical, PO, parenteral (IM, etc.)
primary emulsion
no active ingredients. has non pharmacologic effects
dry gum method
ingredients
how much of each ingredient
what order do the ingredient go in
Mineral oil, distilled water, acacia
4 parts mineral oil
2 parts DI water
1 part acacia
acacia->then mineral oil->then di water
in order to emulsify, you must add energy.
what methods can you do that
mortar and pestle mixing devices shaker jar homogenizer mixer
homogenization
what is it?
what is the benefit?
forcing 2 immiscible liquids through an orifice under high pressure for the purpose of mixing.
increases the stability of the product
types of emulsifiers
what kind of emulsions do they tend to form
examples of each
- gums
a. tend to form o/w
b. ex: acacia, xanthum gum - soaps
a. tend to form w/o
b: olive oil/ lime water
* olive oil contains oleic acid, which is the precursor to the real emulsifier - calcium oleate that forms with the combo of olive oil and lime water. - surfactants
a. can form both o/w and w/o(flexible)
b. Tween 60, propylene glycol monolaurate
advantages of surfactants
more diverse more flexible (can form w/o or o/w) low viscosity (can be advantage or disadvantage)
disadvantages of surfactants
need viscosity enhancers
complex
HLB index
what is it?
applies to what?
what is the index range
hydrophile, lipophile index
indicated the type of emulsion (o/w or w/o) that the emulsifier is best suited for
applies to surfactant type emulsifiers
range 1-20
HLB value 1-9 indicates what
w/o emulsion
HLB value 9-20 indicates what
o/w emulsion
optimal HLB values for an emulsion
2 distinct values:
- specifiied for o-w
- specified for w/o
what is the purpose of using the optimal HLB value for selected emulsifying components
provides greatest stability in terms of micelle formation and integrity, creaming, and cracking
UBSOP how much surfactant to use when compounding emulsion
total surfactant =15% w/v of the emulsions internal phase
how to convert surfactant mass into volume when calculating
use specific gravity. add units to turn it into density. use density to convert from mass to volume
if an active ingredient is dissolved in any phases of an emulsion, can a primary emulsion be made?
NO it cannot. by definition, a primary emulsion is one that does not have any active ingredients
types of infusion settings
Institutial: hospital
Non institutional: skilled nursing facilities, infusion centers, physician offices
accèss for infusions
- peripheral IV lines
- central IV lines
- peripheral inserted central lines (PICC)
- SQ lines
types of peripheral access devices
butterflies- good formal veins. up to 3-5 days
angio catheter-good formal veins. up to 3-5 days
midlines: larger veins. up to 3 mo. easy to maintain
SQ catheters: insufulon: allows for multiple sq injections throughout the sday
Central venous acmes devices
CVP lines: placed by physicians. up to 10 days. site of insertion increases risk for infection. flexibility of drugs that can be used
silastic catheters: surgically placed. lower risk of infection. flexibility of drugs can be used
ex: hickman
implantable ports: placed surgically placed under the tissue. used for intermittent therapies. lower risk of infection. long duratin
PICC lined: used up to 3 mo. but could be longer. not surgically placed
PICC lines
how is it inserted
how long can it be kept in
internal or external device
non surgical insertion
3 month duration
external device
how should lines be maintained?
line flushing
dressing changes
methods to flush lines
purpose:
determine potency, as well as flush lines before and after drug administration
SAS: saline, administer drug, saline
SASH:saline, administer drug, saline, heparin
which lines use which flush methods
peripheral lines: SAS
central lines: SASH
Implantable ports: SASH
Positive pressure caps: SAS
do positive pressure caps need heparin to flush?
no
dressing changes
when do they occur
what are we checking for
day after insertion weekly thereafter check site for 1. infections 2. signs of embolism 3. line migration
how to pick venous access device?
- patient location
- duration/ the of therapy
- method of insertion
- drug characteristics
- maintenance of line
common drugs for infusoin
ABX antifungals anti emetics steroids chemotherapy analgesics electrolytes/ vitamins cardiac medications
infusion methods
gravity
bolus
rate controlled
infusion pumps:MOST COMMON
pharmacist considerations for infusion orders
- what venous access device it is
- drug characteristics
- what diluent
- stability of solution
- volume of infusion
- rate of infusion
expiration dates
can fin din package insert handbook of injectable drugs extended stability of injectable drugs literature manufacturer
TPN
what is it
feeding IV when feeding orally is no an option
when is tPN INDICATED
intractable vominting
diarrhea
bowel obstruction or resection
bowel rest
what is included in TPN
- protein
a. branched chain amino acids - dextrose
hypertonic dextrose used when adding to tan - lipids
a. lipid emulsions with essentially fatty acids - electrolytes
4.additional additives: multivitamins trace metals insulin vitamin K
Harris and Benedict Equation
calculates basic energy expenditure for a patient at rest
caloric needs categories
mild impairment: 25-28kcal/kg/day
moderate impairment 28-32 kcal/kg/day
sever impairment: 30-35
TPN ordering
develop formula based on pt needs. never an emergent therapy
complications of tpn
CATHETER SEPSIS
vt
HEAPTIC FATTY LIVER OR CHOLECYSITITIS
metabolic conditions
what to monitor for with TPN
weight: weight gain of 1-2 lbs per week
2. nutritoinal profile
3. BMP
4. glucose (finger sticks)
5. urea nitrogen
TPN for special populations
diabetes acute renal failure pulmonary disease (give them more fat than dextrose) hepatic disease cardiac disease
methods to preparing TPN solutions
- manual mixing
2. automated compounders
TPN infusions done with what device
via pump
how to find composite hlg when given surfactant quantities
- ude density and surfactant volume to find the mass of each surfactant
- add the masses of the 2 to get the total masses of emulsifiers
- find the value of f for first surfactant by dividing the mass of the surfactant by the total mass of the 2 surfactants.
- find f of second surfactant by subtracting f of first from 1.
do the cross method with the middle part being x. you will get the parts equation for each. set up a whole equation to figure out the parts
