MOD 7 - COURSE 4 - PT 2 - SC-ORAL

Question 1

WHta is the use of SC injection

Answer 1

• adminsitrating large volume of many substance - slow release avoiding first pass liver metabolsims

Question 2

Where is SC injected into

Answer 2

• placed more vascular s[ace between skin and underlying msucles
• obviosu bulge in sckin - noted after injection of large quanitity
• preffered site - most lab aniamsl = back interscapular region

Question 3

what is a procedure of doing SC injections

Answer 3

• manually restrain the mouse usng the scruff method
• amek a tent of skin at scruff or rump
• insert needle at 45’ anfle between the fingers - careful not to push needle through the other side
• while maintaining the grip of scruff and the base of tial lift mouse and secure its tail between 3rd and 4th finger and your palm
• insrert needle under the skin overlying the upper thrigh and lower part of back of abdo
• is placed the needle properly under skin - no resistant if moved from left to right
• injection solution a small bled in SC space - should be ntoed - rotate needl 180 - before removing na dpress the skin to seal the neeles exit - prevent fluid from leaking out
• apply hentl pressureing to the site to prevent backflow of the material

Question 4

list some example of locations for SC injection

Answer 4

• over shoulder into loose skin over neck or loose fold over flank

Question 5

for injection with SC what are the chemcial charactersitics needed for SC injections

Answer 5

• if the maerial = irritant/cytotoxic, bad osmolarity, extreme pH = very painful
• and sterilise fluid
• make sure piolt studies confirm if toxic or not

Question 6

for small rodents - do you need to disineft site of injection

Answer 6

• no - ntot with alcohol
• cause losso f body heat and distrun microbiota
  (farmaniamls - clean injection site)

Question 7

what can happen with incorrect insertion of neelde

Answer 7

• puncture blood vessel, msucles - hurt animals

Question 8

if injection = successful what is likely to see

Answer 8

• swelling under skin seen

Question 9

how may sites of injections per day = maximum

Answer 9

4

Question 10

what is the appropriate needle size ad injection volume for SC injection for mouse

Answer 10

• 25g
• 10(40)ml/kg

Question 11

what is the appropriate needle size ad injection volume for SC injection for rat

Answer 11

25g
5 (10) ml/kg

Question 12

what is the appropriate needle size ad injection volume for SC injection for guinea pigs

Answer 12

23-25g
5-10ml

Question 13

what is the appropriate needle size ad injection volume for SC injection for ahmsters

Answer 13

23-25g
3-4ml

Question 14

what is the appropriate needle size ad injection volume for SC injection for rabbit

Answer 14

21-25g
1 (2) ml/kg

Question 15

what is the appropriate needle size ad injection volume for SC injection for dog

Answer 15

21-23g
1 (2) ml/kg

Question 16

what is the appropriate needle size ad injection volume for SC injection for macague

Answer 16

23-25g
2(5)ml/kg

Question 17

shat is the intradermal inection

Answer 17

• used for assessment of immune, inflammatory or sensitisaition response

Question 18

what is a intradermal injection

Answer 18

• outer layer of skins – usually on back

Question 19

is anaesthesia used for ID injection

Answer 19

• although not painful - anaesthesia used to immobilize aniamsl = difficult to accurately place compound in conscious aniamls

Question 20

what is the procedures for intradermal injection

Answer 20

• shave a small area along the injection site - scleanse with antiseptic
• pinch and list the skin gently from the back
• insert the needle just under the epithelium at a s light anfle – needle shouldnt go into subcutanous space
• slowly inject ht esolution - small bleb = appear at inejction site
• apply moderate/gentle pressure to the site to prevent fluid from leaking back out

Question 21

what is the max volume per site of ID injection

Answer 21

• normally 100ul per site 50ul in some instances - multiple injections = mescessary for a larger quanity - not more than 6

Question 22

when doing multiple injection sites what should you use to account for regional variations in skin thickness

Answer 22

latin square system

Question 23

even without inflammation intradermal injection injection can cause distres or pain - what can you do to help with pain

Answer 23

• consider use of local anaesthic cream
• minimise adverse efecent - splitting dose over a few sites
• do not inject individual site more than once

Question 24

what can you do to help with needle sinsertion

Answer 24

• density of skin - may make needle insertion difficult
• use smallest an dsharpest needle will penetrate the skin

Question 25

whats the max number of sites of injection

Answer 25

6

Question 26

what is the appropriate needle size and injection volume for ID injection for mouse and rats

Answer 26

27g 50ul/site

Question 27

what is the appropriate needle size and injection volume for ID injection for guinea pigs and hamsters

Answer 27

25g 50ul/site

Question 28

what is the appropriate needle size and injection volume for ID injection for rabbits, ferrets, dog, cat and Non human primates

Answer 28

25g 50-100ul/site

Question 29

what is enteral administration

Answer 29

- mainly oral route - sublingual - not commonly used in lab animals rectal drug administered intro GI tract - reduced bioadabilabilit

Question 30

what is required for enteral administration

Answer 30

there is good absorption from GI tract

Question 31

why might dose concentration of enteral administration be differnt when into blood

Answer 31

as drug passess down the GI tract - part of the dose - my nto be available for absoprtion because of checmical degradation, phsycial inactivation through binding or complexation, microbial biotransformation - of that which is absorbed some may reach the heptatic portel vein - be extracted by iver by way fo ezymemetabolism or bilary excretion - first pass effect

Question 32

what is some negatives and positives of oral administration by mouth

Answer 32

- needs to be palatable otherwise needs to be by volunrary injections from dosing device - oral adininstration may be less stressful - closely mimin ingestions of substance in humans - less acurrate regarding actual doe ingested by aniamls - essentail to underestand feeding behaviour of specie - to determine best way of incroperating subtance into diet

Question 33

how can you improve palatability of drugs

Answer 33

- consider forumulations i.e. microencaspulatiosn - mask unpleastent flavous - adding suger or food flavours - consider metbaolic rate,age and conditions befor withholfing nromal food to force aniaml to eact treated food

Question 34

whats the probelm with non single house aniamls - with oral administration

Answer 34

- hard to know how mcuh theyve eaten - so may need to be single house - but then - isolated :(

Question 35

what are key consideration for oral gavage procedures

Answer 35

- 10ml/kg reccomeneded vol for mice - 5-10ml/kg (rat) - align hea dand body vertically with oesophagus the mouses position = veyr important - do not aspirate - administer compound slowly - finish administrating before pulling out - stop if mucous membrane = blue- mouse struffled vivgourously or fluids comes form nose

Question 36

when use oral adminsitration by gavage ?

Answer 36

- when accurate dose is needed - the drug will undego exensive hepatic first pass metabolism - so bioadvailability will decreases - avoid lingual or buccal absorption

Question 37

describe the proceudre of oral gavage

Answer 37

firmly restrain mouse using scruff restraint methof - head and bosy = vertically aligned with oesophagus - mouse - face me -louse scruff - firmly secured - head = immobalised - insert feeding needle behinf te incissors towards backk of throat - feel hard palate then the soft palae - insert oesophagys - allow mouse to swallow the feeding needle down - DO NOT FORCE - needle should be eaily moved down - depth of feedle needle - aproporaiete from prev measurment - inject compound slowly - pull needle straight out - observe aniamsl fror any adverse signs

Question 38

what are some animal welfare issue of oral gavage

Answer 38

- if tube = incorrectly - may penentrate trachea - pass through osopheagus - stomach wall into thoracic or peritoneal cavity - repeated gavaging - cause inflammation or oroppharynx - cause deatg of aniaml - due to asphyscia - due to impacting food

Question 39

how to improve aniamsl welfare when performing oral gavaging

Answer 39

- be familiar with anatomical relationship - of oropharynx and train enough to master technique - correct restrain is essential - use correct size feeding tube - ensure dose enters stomach not oesophagus - anaestheedia or sedation - increase risk of aspiration - material inadverntly entering lungs

Question 40

do you need to fast before oral gavage

Answer 40

- up to 18 hours - reccomended empty stomach before dosing - alsoways question the necessity for sating - if food can affect drug absorption - reduce time of fasting for minmum stomach of rat = empty after 6 hours

Question 41

whats the reccomeneded volume for oral gavage in mice

Answer 41

10ml/kg

Question 42

whats the reccomeneded volume for oral gavage in rats

Answer 42

5-10

Question 43

whats the reccomeneded volume for oral gavage in huinea pig, rabbit, dog, macague

Answer 43

5ml/kg

Question 44

whats the reccomeneded volume for oral gavage in minipigs

Answer 44

10ml/kg

Question 45

when is drugs given rectally

Answer 45

most commonly given as suppository or enema - solution - drug absoption from suppository = incomplete or erratic - absorption from soltuion = reliable - some bu not all of veins - draining hthe rectum - lead directl to general circulation - bypassing liver - reduce first pass effects by this route