Pain - Methods Of Administering Analgesics

Front 1

Routes of administration

Back 1

-Oral
-SQ, IM, IV
-Topical
-Transdermal
-Transmucosal
-Preineural
-Intravenous Regional
-Intra-articular
-Interpleural
-Epidural
-Intrathecal (spinal, subarachnoid)

Front 2

Methods of dosing drugs SQ, IM, IV

Back 2

-Intermittent
-CRI

Front 3

Methods of dosing drugs transmucosally

Back 3

-oral buccal or sublingual
-intranasal
-rectal

Front 4

Oral analgesics
-pros

Back 4

-easier for some owners to administer than injectable drugs
-occasionally more economical than injectable drugs

Front 5

Oral analgesics
-cons

Back 5

-many have poor bioavailability
-animals must be alert enough in order to take oral medication

Front 6

Oral analgesics
-major factor in oral bioavailability

Back 6

-first pass effect due to liver metabolism

Front 7

Oral analgesics
-poor assumption

Back 7

-don't assume that a drug will reach adequate plasma levels in animals because it does so in people

Front 8

Oral analgesics
-oral administration of opioids

Back 8

-bioavailability is low in dogs due to erratic absorption and metabolism by the liver

Front 9

Oral Analgesics
-problems with administering drugs in food

Back 9

-many animals being given analgesic drugs are not eating as well as we'd like them to be
-hiding medication in food can affect an animals willingness to eat the food even after stopping medication

Front 10

SQ, IM, IV
-bioavailability

Back 10

-better than oral

Front 11

Drugs that typically cannot be given parenterally

Back 11

-Nonsteroidals

Front 12

SQ dosing
-cons

Back 12

-administration in patients with poor peripheral perfusion

Front 13

Benefits of CRI (over intermittent dosing)

Back 13

-constant plasma levels of the drug
-eliminates the need for frequent injections
-more constant analgesia

Front 14

How to predict the steady state of a drug administered via CRI

Back 14

-by half-life

Front 15

How to begin a CRI

Back 15

-administer a bolus dose to achieve appropriate plasma levels quickly

Front 16

Methods for administering CRIs

Back 16

-Fluid pump
-Syringe pump

Front 17

CRIs are good for administering what kinds of drugs

Back 17

-those with short half-lives

Front 18

Topical drugs
-most often refer to

Back 18

-drugs applied to the cornea

Front 19

Topical proparacaine
-use

Back 19

-local anesthetic

Front 20

Topical morphine
-use

Back 20

-ulcers

Front 21

Splash block
-define

Back 21

-form of local anesthetic block where the drug is applied directly to the site of interest

Front 22

Splash block
-most commonly performed where?

Back 22

-peritoneum
-ovarian ligaments
-soft tissue surgery sites

Front 23

Efficacy of topical application depends on:

Back 23

-contact time
-solubility of drug in tissue
-concentration and dosage of the drug

Front 24

Transdermal
-drugs

Back 24

-Fentanyl patch
-Buprenorphine
-Lidocaine patches, ointments, creams
-Benzocaine creams
-Clonidine

Front 25

Lidocaine patch
-use

Back 25

-herpetic pain
-chronic regional pain syndrome

Front 26

Fentanyl patch
-reason for mixed results

Back 26

-unpredictable
-wide range of plasma fentanyl levels

Front 27

Are fentanyl patches supported for post surgical pain?

Back 27

-NO

Front 28

Transdermal drugs
-pros

Back 28

-absorbed into the blood (no first pass elimination)
-possibly useful for chronic pain (not yet known)

Front 29

Transdermal drugs
-cons

Back 29

-must be kept in contact with skin
-potential for accidental ingestion by animals or people
-potential for abuse

Front 30

Recuvrya
-define

Back 30

-transdermal fentanyl licensed in Europe for Dogs only
-topical liquid applied to the skin

Front 31

Recuvrya
-administration

Back 31

-single, rapid drying, small volume
-applied 2-4 hrs before surgery
-delivers fentanyl to the Stratum Corneum

Front 32

Recuvrya
-pros

Back 32

-non-invasive dosing
-avoidance of first-pass effect
-steady continuous drug delivery
-sustained therapeutic plasma fentnayl concentrations for at least 4 days

Front 33

Recuvrya
-cons

Back 33

-rapid mucosal transfer with high bioavailability (must wear gloves, goggles, gown)
-can transfer small amounts from skin for up to 72 hrs
-hypothermia
-unknown concurrent use with NSAIDs

Front 34

Transmucosal
-pros

Back 34

-avoid first pass elimination

Front 35

Transmucosal
-routes of administration

Back 35

-buccal mucosa
-sublingual
-intranasal
-rectal

Front 36

Buccal mucosa
-drug administration

Back 36

-buprenorphine in cats
-fentanyl lollipops
-fentanyl patch abuse

Front 37

Sublingual
-drug administration

Back 37

Buprenorphine
-suboxone film
-naloxone film

Front 38

Intranasal
-drug administration

Back 38

-Fentanyl
-local anesthetic for nasal biopsies

*probably not very useful

Front 39

Rectal
-drug administration

Back 39

-poor bioavailability in dogs and cats

Front 40

Transmucosal drug administration
-use

Back 40

-many for control of breakthrough pain in cancer patients
-more easily administered in some pediatric patients

Front 41

Buccal absorption of opioids
-depends on

Back 41

-pH
*limited by acidic environment

Front 42

Buprenorphine
-use

Back 42

-cats

*will not work if swallowed

Front 43

Perineural administration
-use

Back 43

-administration of local anesthetics
-some applicability for opioids

Front 44

Effect of administering opioids with local anesthetics

Back 44

-prolonged local anesthetic block

Front 45

How to get local anesthetic to infiltrate into an area?

Back 45

-administer around nerves/nerve bundles

Front 46

Purpose of administering local anesthetic around nerves/nerve bundles

Back 46

-pre-emptive analgesia

Front 47

Intravenous regional anesthesia
-aka

Back 47

-Bier block

Front 48

Bier block
-define

Back 48

-Iv injection of large volumes of dilute local anesthetic into an extremity isolated from the rest of the circulation by a tourniquet

Front 49

Bier block
-function

Back 49

-diffusion across blood vessels to local nerves
-blocks tissue distal to the tourniquet
-quick return of nerve and muscle function after release of tourniquet

Front 50

Bier block
-typically not done where

Back 50

-areas with lots of muscle mass

Front 51

Bier block
-common use

Back 51

-food animals for distal limb procedures

Front 52

Intra-articular administration
-drugs

Back 52

-local anesthetics
-opioids

Front 53

Intra-articular opioids
-use

Back 53

-trauma/inflammation may activate opioid receptor on nociceptive nerve terminal and/or inflammatory cells
-morphine injected into joints at the end of surgery may be able to enhance post-operative analgesia for joint surgery

Front 54

Intrapleural
-drugs

Back 54

-Bupivicaine (local anesthetic)

Front 55

Intrapleural analgesia
-define

Back 55

-nerve block to provide analgesia and anesthesia to thoracic and cranial abdominal pain

Front 56

Itrapleural analgesia
-use

Back 56

-pancreatitis
-post-thoracotomy
-patients with chest tubes for pleural space disease

Front 57

Intrapleural analgesia
-con

Back 57

-if dose is too high or too frequent con have local anesthetic toxicity

Front 58

Stages of anesthetic toxicity

Back 58

Restless --> Nauseous ---> CNS & Cardiotoxicity

Front 59

Epidural analgesia
-define

Back 59

-injection of a drug into the space outside of the meninges of the spinal cord (not in spinal fluid)

Front 60

Epidural analgesia
-drugs

Back 60

-opioids*
-local anesthetics*
-NMDA antagonists
-A-2 agonists
-steroids
-cholinergic antagonists

*most commonly used

Front 61

Alpha-2 agonist with a local effect

Back 61

-xylazine

Front 62

Epidural analgesia
-location for injection in dogs, cats, pigs

Back 62

-lumbosacral space

Front 63

Epidural analgesia
-location for injection in horses and cattle

Back 63

-sacral coccygeal

Front 64

Epidural analgesia
-what to do if you find you're in spinal fluid

Back 64

-lower the dose

Front 65

Epidural analgesia
-what can happen if you enter the meninges

Back 65

-spinal fluid leak ---> spinal headache

Front 66

Epidural analgesia
-site of action depends on

Back 66

-drug type used

Front 67

Epidural analgesia
-opioid site of action

Back 67

-dorsal horn

Front 68

Epidural analgesia
-local anesthetic site of action

Back 68

-spinal nerves before they leave the vertebral column

Front 69

Epidural catheter
-purpose

Back 69

-continuous/frequent administration of drugs into the epidural space

Front 70

Epidural catheter
-indications

Back 70

-pelvic/hindlimb fractures
-thoracic epidural analgesia
-severe soft tissue trauma
-chronic pancreatitis
-open abdomen

Front 71

Intrathecal/Spinal Analgesia
-define

Back 71

-injection of drug into the subarachnoid space to provide more rapid onset than epidural administration

*potential for more cranial spread of drug