Euthanizing Agents

Question 1

Euthanasia
Derived from the Greek terms eu meaning _____ and thanatos meaning ______.

The term is used to describe “ending the life of an individual animal in a way
that minimizes or eliminates pain and distress” American Veterinary Medical
Association, 2020

➢ In order to be considered euthanasia, the procedure must result in ______ loss of
consciousness, followed by loss of _____ body functions
→ ?

Answer 1

Euthanasia
Derived from the Greek terms eu meaning good and thanatos meaning death
The term is used to describe “ending the life of an individual animal in a way
that minimizes or eliminates pain and distress” American Veterinary Medical
Association, 2020
➢ In order to be considered euthanasia, the procedure must result in rapid loss of
consciousness, followed by loss of vital body functions
→ respiration, heartbeat, and brain function

Question 2

“Because veterinarians are committed to improving animal and human health and welfare, and because they work tirelessly to discover causes and cures for animal diseases and promote good animal management, some may feel a sense of disquiet or defeat when euthanasia becomes the better course of action.”
AVMA Guidelines for the Euthanasia of Animals, 2020

Answer 2

“Because veterinarians are committed to improving animal and human health and welfare, and because they work tirelessly to discover causes and cures for animal diseases and promote good animal management,
some may feel a sense of disquiet or defeat when euthanasia becomes the better course of action.”
AVMA Guidelines for the Euthanasia of Animals, 2020

Question 3

Euthanasia
American Veterinary Medical Association (AVMA)

Since 1963 the AVMA has convened a Panel on Euthanasia (POE) to evaluate methods
and potential methods of euthanasia for the purpose of creating guidelines for
veterinarians

Methods, techniques, and agents of euthanasia have been updated and detailed descriptions have been included to assist veterinarians in applying their professional judgment

Answer 3

Euthanasia
American Veterinary Medical Association (AVMA)

Since 1963 the AVMA has convened a Panel on Euthanasia (POE) to evaluate methods
and potential methods of euthanasia for the purpose of creating guidelines for
veterinarians

Methods, techniques, and agents of euthanasia have been updated and detailed descriptions have been included to assist veterinarians in applying their professional judgment

Question 4

–> American Veterinary Medical Association (AVMA)
* The scope of the 1963 edition was limited to methods and recommendations applicable to
_____, ____ and other ______ mammals
* Editions published in 1972 and 1978 encompassed more methods and species (_______ animals and ____ animals respectively)
* In 1986 information on ________, _______, and ____-bearing wildlife was introduced
* In 1993 recommendations for _____ and ______ were added
* The 2020 iteration of the Guidelines constitutes the ninth edition of the POE’s report. Two years of review, discussion, and revision

Answer 4

–> American Veterinary Medical Association (AVMA)
* The scope of the 1963 edition was limited to methods and recommendations applicable to
dogs, cats and other small mammals
* Editions published in 1972 and 1978 encompassed more methods and species (laboratory
animals and food animals respectively)
* In 1986 information on poikilothermic, aquatic, and fur-bearing wildlife was introduced
* In 1993 recommendations for horses and wildlife were added
* The 2020 iteration of the Guidelines constitutes the ninth edition of the POE’s report. Two
years of review, discussion, and revision

Question 5

➢ It is crucial that euthanasia be performed with consideration of the animal’s _______ and with highest degree of ________.
➢ All aspects of euthanasia, not just the method chosen, should be evaluated to ensure that pain and distress are ________.

Answer 5

➢ It is crucial that euthanasia be performed with consideration of the animal’s welfare and with highest degree of respect
➢ All aspects of euthanasia, not just the method chosen, should be evaluated to ensure that pain and distress are minimized

Question 6

Important aspects
Pre-euthanasia procedures → handling, restraint, the environment
* Proper ____________ is vital to minimize pain and distress in animals, to ensure the safety
of the person performing the euthanasia, and to protect other people and animals
* The amount of control and kind of restraint required will be determined by the
_______, _____, and ______ of animal involved
* Careful confirmation of death
* It is prudent that the animal’s remains, and euthanasia solutions are used and disposed
of __________ and _______

Answer 6

Important aspects
Pre-euthanasia procedures → handling, restraint, the environment
* Proper handling is vital to minimize pain and distress in animals, to ensure the safety
of the person performing the euthanasia, and to protect other people and animals
* The amount of control and kind of restraint required will be determined by the
species, breed, and size of animal involved
* Careful confirmation of death
* It is prudent that the animal’s remains, and euthanasia solutions are used and disposed
of appropriately and legally

Question 7

–> Important aspects
* Owners should be given the opportunity to be ___________ during the euthanasia
* What _______ are being used and how the animal could _________ should be discussed
* Behaviors such as vocalization, agonal breaths, muscle twitches, failure of the eyelids
to close, urination, or defecation can be distressing to owners
* Distress may develop among personnel directly involved in performing euthanasia
repeatedly, and may include a psychological state characterized by a strong sense of
work dissatisfaction

Answer 7

–> Important aspects
* Owners should be given the opportunity to be present during the euthanasia
* What drugs are being used and how the animal could respond should be discussed
* Behaviors such as vocalization, agonal breaths, muscle twitches, failure of the eyelids
to close, urination, or defecation can be distressing to owners
* Distress may develop among personnel directly involved in performing euthanasia
repeatedly, and may include a psychological state characterized by a strong sense of
work dissatisfaction

Question 8

➢ Euthanasia methods for animals can be divided into two primary groups
→ _________
→ ___________
➢ And three basic mechanisms
* Direct _________ of neurons vital for life functions
* _________
* _________ destruction of neurons and brain activity vital for life

Answer 8

➢ Euthanasia methods for animals can be divided into two primary groups
→ Chemical
→ Physical
➢ And three basic mechanisms
* Direct depression of neurons vital for life functions
* Hypoxia
* Physical destruction of neurons and brain activity vital for life

Question 9

Evaluating methods of euthanasia, the POE considered the following criteria as outlined by
the AVMA Guidelines for the Euthanasia of Animals, 2020
1. Ability to induce loss of consciousness and death with a minimum of pain and distress
2. Time required to induce loss of consciousness
3. Reliability
4. Safety of personnel
5. Irreversibility
6. Compatibility with intended animal use and purpose
7. Documented emotional effect on observers or operators
8. Compatibility with subsequent evaluations, examinations, or use of tissue
9. Drug availability and human abuse potential
10.Compatibility with species, age, and health status
11.Ability to maintain equipment in proper working order
12.Safety for predators or scavengers should the animals remains be consumed
13.Legal requirements
14.Environmental impacts of the method and disposition of animal’s remains

Question 10

It is essential that personnel are educated and trained in the appropriate and safe techniques for all aspects of euthanasia
→ understand the underlying justifications for euthanasia. It can help mitigate any psychological impacts on the individual
(__________-_________ paradox)

Answer 10

It is essential that personnel are educated and trained in the appropriate and safe techniques for all aspects of euthanasia
→ understand the underlying justifications for euthanasia. It can help mitigate any psychological impacts on the individual
(caring-killing paradox)

Question 11

–> If the method chosen involves controlled substances
➢ Proper _______ and ________ control → to prevent abuse (_______)

Answer 11

–> If the method chosen involves controlled substances
➢ Proper storage and diversion control → to prevent abuse (suicide)

Question 12

Most euthanasia agents have a _______ therapeutic index or _________ side effects and are not used in human medicine
________, ______, ____, _______, and others have been used in suicide or suicide attempts

Answer 12

Most euthanasia agents have a narrow therapeutic index or excessive side effects and are not used in human medicine
Acepromazine, xylazine, T-61, barbiturates, and others have been used in suicide or
suicide attempts

Question 13

Injectable agents delivered __________ are generally the most rapid, reliable, and preferred method of euthanasia for most species
—> _____________ administration is the preferred route

_______ to _______ times the therapeutic dose of an anesthetic will produce rapid and uniform cardiac arrest and death

Answer 13

Injectable agents delivered parenterally are generally the most rapid, reliable, and preferred method of euthanasia for most species
—> Intravenous administration is the preferred route

Three to four times the therapeutic dose of an anesthetic will produce rapid and uniform cardiac arrest and death

Question 14

__________ are the most widely used and accepted agent for euthanasia when administered IV
➢ _________ __________- → the most suitable
This group includes:
* _________ acid derivatives, _________ → sodium pentobarbitone; secobarbital
* ____________ → thiopentone
Advantages
1. ________ of action
2. They induce euthanasia ________
3. Barbiturates are ______ expensive
4. Food and Drug Administration-approved barbiturate-based (readily available)

Answer 14

Barbiturates are the most widely used and accepted agent for euthanasia when administered IV
➢ Sodium pentobarbital → the most suitable
This group includes:
* Barbituric acid derivatives, oxybarbiturates → sodium pentobarbitone;
secobarbital
* Thiobarbiturates → thiopentone
Advantages
1. Speed of action
2. They induce euthanasia smoothly
3. Barbiturates are less expensive
4. Food and Drug Administration-approved barbiturate-based (readily available)

Question 15

Barbiturates
* They cause severe _______ of the CNS. Barbiturates interfere with ______ and _______ transport across cell membranes, blocking _________ transmission
* At high doses they bind directly to the _______ → dose-dependent rapid sedation,
hypnosis, anesthesia, and eventually respiratory depression and death
* It is important the proper disposal of both the agent, as a controlled substance, and
carcass, to avoid poisoning of scavenging wildlife

Answer 15

Barbiturates
* They cause severe depression of the CNS. Barbiturates interfere with sodium and potassium transport across cell membranes, blocking postsynaptic transmission
* At high doses they bind directly to the GABA → dose-dependent rapid sedation,
hypnosis, anesthesia, and eventually respiratory depression and death
* It is important the proper disposal of both the agent, as a controlled substance, and
carcass, to avoid poisoning of scavenging wildlife

Question 16

Barbiturates
Disadvantages
1. ___________ injection
2. Each animal must be appropriately ________
3. Current federal drug regulations require strict _________, and these must be
used under the supervision of personnel registered with the US DEA
4. Terminal _____ may occur in unconscious animals
5. Some animals may go through an _________ phase
6. These drugs persist in the animal’s _______
7. Tissue ______ (e.g., splenomegaly) may occur
DEA: Drug Enforcement Agency

Answer 16

Barbiturates
Disadvantages
1. Intravenous injection
2. Each animal must be appropriately restrained
3. Current federal drug regulations require strict accounting, and these must be
used under the supervision of personnel registered with the US DEA
4. Terminal gasp may occur in unconscious animals
5. Some animals may go through an excitatory phase
6. These drugs persist in the animal’s remains
7. Tissue artifacts (e.g., splenomegaly) may occur
DEA: Drug Enforcement Agency

Question 17

Barbiturates
* Intravenous injection of a barbituric acid derivative is the preferred method for euthanasia of ____, ____, other ______ animals, and _________
* Barbiturates are also acceptable for ___ other species of animals if circumstances
permit their use
* When an IV injection would be distressful, dangerous, or difficult due to small
patient size _________ injection may be used
* Intracardiac injection must only be used if the animal is ________ or ________

Answer 17

Barbiturates
* Intravenous injection of a barbituric acid derivative is the preferred method for euthanasia of dogs, cats, other small animals, and horses
* Barbiturates are also acceptable for all other species of animals if circumstances
permit their use
* When an IV injection would be distressful, dangerous, or difficult due to small
patient size intraperitoneal injection may be used
* Intracardiac injection must only be used if the animal is unconscious or anesthetized

Question 18

Tributame
It is a ___________ euthanasia agent and contains: (3?)
➢ Embutramide, a derivative of γ-hydroxybutyrate, is an anesthetic with a strong ________ effect
➢ It acts by causing respiratory ________ in the CNS and induces _______ anesthesia

Answer 18

Tributame
It is a nonbarbiturate euthanasia agent and contains: Embutramide, chloroquine phosphate, and lidocaine
➢ Embutramide, a derivative of γ-hydroxybutyrate, is an anesthetic with a strong narcotic effect
➢ It acts by causing respiratory depression in the CNS and induces deep anesthesia

Question 19

Tributame
Severe cardiovascular effects
→ _________
→ myocardial __________
→ ventricular __________

All result in ________

Answer 19

Tributame
Severe cardiovascular effects
→ hypotension
→ myocardial depression
→ ventricular dysrhythmias

All result in death

Question 19

Tributame
Severe cardiovascular effects
→ hypotension
→ myocardial depression
→ ventricular dysrhythmias

All result in death

Question 20

Tributame
➢ __________ ____________, an antimalarial drug, was added to shorten the time to unconsciousness and death → a profound cardiovascular depressant
➢ _________ was added to reduce the pain associated with IV injection in cats
* Death occurs as a result of CNS ________, respiratory _______ and ______, and ________ collapse
* It should only be administered _____ and caution should be taken by _____ (extralabel)
→ ________ breathing may occur

Answer 20

Tributame
➢ Chloroquine phosphate, an antimalarial drug, was added to shorten the time
to unconsciousness and death → a profound cardiovascular depressant
➢ Lidocaine was added to reduce the pain associated with IV injection in cats
* Death occurs as a result of CNS depression, respiratory depression and hypoxia, and circulatory collapse
* It should only be administered IV and caution should be taken by cats (extralabel)
→ Agonal breathing may occur

Question 21

Tributame: Advantages
1. ______ onset of action
2. Tributame induces euthanasia _______, with ________ discomfort to the animal
3. Schedule _____ status makes Tributame somewhat simpler to obtain, store, and administer than Schedule II drugs (?)

Answer 21

Tributame: Advantages
1. Rapid onset of action
2. Tributame induces euthanasia smoothly, with minimal discomfort to
the animal
3. Schedule III status makes Tributame somewhat simpler to obtain,
store, and administer than Schedule II drugs (sodium pentobarbital)

Question 22

Tributame: Disadvantages
1. It is not currently being __________
2. ________ injection (other routes of administration are not acceptable)
3. Each animal must be appropriately ______
4. Aesthetically objectionable _____ breathing may occur in unconscious
animals
5. The component drugs tend to persist in the animal’s _______

Answer 22

Tributame: Disadvantages
1. It is not currently being manufactured
2. Intravenous injection (other routes of administration are not acceptable)
3. Each animal must be appropriately restrained
4. Aesthetically objectionable agonal breathing may occur in unconscious
animals
5. The component drugs tend to persist in the animal’s remains

Question 23

T-61 (Tanax®)
T-61 is a nonbarbiturate agent that contains:?
➢ Mebenzonium iodide is a _______ ____ agent
➢ Tetracaine hydrochloride, a _____ anesthetic
* It has been described as a euthanasia agent for dogs (___), amphibians (?), small birds (___)
* T-61 has a similar induction of euthanasia as ____________.

Answer 23

T-61 (Tanax®)
T-61 is a nonbarbiturate agent that contains:
Embutramide, mebezonium iodide, and tetracaine hydrochloride
➢ Mebenzonium iodide is a nondepolarizing NMB agent
➢ Tetracaine hydrochloride, a local anesthetic
* It has been described as a euthanasia agent for dogs (IV), amphibians (dorsal
lymph sac), small birds (IM)
* T-61 has a similar induction of euthanasia as pentobarbital.

Question 24

T-61 (Tanax®)
Advantages
1. _______ onset of action. It has been used to euthanize dogs, cats, horses, laboratory animals, birds, and wildlife
2. The terminal (agonal) gasp that sometimes accompanies barbiturates are ___ seen with use of T-61

Answer 24

T-61 (Tanax®)
Advantages
1. Rapid onset of action. It has been used to euthanize dogs, cats, horses,
laboratory animals, birds, and wildlife
2. The terminal (agonal) gasp that sometimes accompanies barbiturates
are not seen with use of T-61

Question 25

T-61 (Tanax®)
Disadvantages
1. It is ___ currently being manufactured
2. _______ IV injection is necessary to avoid dysphoria prior to unconsciousness
3. Each animal must be __________ restrained
4. Secondary toxicosis may occur in animals that ___________ remains of animals
euthanized with T-61

Answer 25

T-61 (Tanax®)
Disadvantages
1. It is not currently being manufactured
2. Slow IV injection is necessary to avoid dysphoria prior to unconsciousness
3. Each animal must be appropriately restrained
4. Secondary toxicosis may occur in animals that consume remains of animals
euthanized with T-61

Question 26

Question 27