PDD Incompatability Lecture

Question 1

Interaction

Answer 1

Inside the body and therefore cannot be seen

Question 2

Incompatibility

Answer 2

Occurs inside a fluid container or infusion line and is usually visible

• Physical or chemical incompatibilities or interactions that take place before admin
• Failure of a drug or drug mixture to combine with another

Question 3

Incompatibility Occur

Answer 3

Mixing solution NOT recommended

• Difficulties with venous access limiting the number of IV lines
• At home requirement of many drugs simultaneous continuous infusion

Question 4

Physical Incompatibility Evolution of Gas

Answer 4

Carbonates and bicarbonates with acidic drugs

Question 5

Physical Incompatibility Color change or darkening

Answer 5

Indicate chemical breakdown

Question 6

Physical Incompatibility Adsorption

Answer 6

Drugs are adsorbed to the lining of IV containers and tubing or admin set

• Minimized by short lengths of small diameter tubing
• Nitroglycerin to polyvinyl chloride (saturate with nitroglycerin)

Question 7

Physical Incompatibility Diazepam Adsorption

Answer 7

Therapy for convulsions, anxiety and preoperative and postoperative anesthesia
- PLASTIC tubing

Question 8

Physical Incompatibility Leaching

Answer 8

Extraction of certain materials from teh container into the solution it is holding
DEHP
Increased pliability and optical clarity
Hepatotoxic and a known carcinogen

Question 9

Physical Incompatibility DEHP

Answer 9

Leach from PVC containers

Replaced with bags made of ethylene vinyl acetate or other less reactive materials

Question 10

Non-containing DEHP plastics or glass materials where leaching may be a problem

Answer 10

TAXOL (pacilataxel)

Question 11

Physical Incompatibility Etoposide Leaching

Answer 11

Antineoplastic agent

Includes Polysorbate 80 but this can react with DEHP

Question 12

Formation of precipitates

Answer 12

Occurs when alkaline solution mixed with acidic solution

Calcium salts precipitate when added to a basic medium

Question 13

Co-Precipitation Reactions

Answer 13

Involves Calcium and Phosphate via infusion containing soluble salts to form dibasic calcium phosphate –> emoblism

Question 14

Aqueous Solubiity of Calcium Phosphate Species

Answer 14

Phosphate is trivalent anion with 3 different dissociation constants
2.16, 7.21, 12.32
Produces mono, di, and tri basic Ca Phosphate with calcium

Question 15

Dibasic Ca HPO3

Answer 15

Is 0.3 mg/mL and happens around 7.21

Question 16

Tribasic Ca3PO42

Answer 16

0.001 mg/mL and happens around 12.32 which is beyond physiological pH

Question 17

Incompatabilities involving Ca and P

Answer 17

Premature infants require relatively high amounts of Ca and P per body weight
Often intolerant to enteral feeding due to immature of digestive tract

Question 18

Challenges of Ca and P

Answer 18

Depends on pH and concentrations may lead to insoluble salt forms
Limited volume: 120-180 mL
Precipitation: Too high of concentration

Question 19

Phosphates

Answer 19

Avaliable as mono and dibasic salts of potassium or sodium

Question 20

Effects of additives

Answer 20

Amino Acids: form soluble complexes with Ca –> depletes a for precipitation
Lower pH: Less change of ppt
Calcium Glucorate instead of CaCl
Inline filter – prevent potential danger

Question 21

Organic phosphates

Answer 21

Potential alternative for inorganic phosphates for IV use

Question 22

Decomposition

Answer 22

Bc mixing of two different parenteral formulations that may result in toxicity and loss of therapeutic efficacy

Question 23

Complexation

Answer 23

May occur between drugs, inactivating them

Question 24

Hydrolysis

Answer 24

Esters, amides and lactams

Question 25

Oxidation

Answer 25

When one drug loses electrons to the other

May turn color and make it therapeutically inactive!

Question 26

Reduction

Answer 26

Takes place when one drug gains electrons from the other

Question 27

Photolysis

Answer 27

Chemical decomposition caused by light

Can lead to hydrolysis or oxidation with resulting discoloration

Question 28

Therapeutic incompatibilities occur

Answer 28

When two or more drugs are combined and the result is a response other than that intended