Week 6 - Pre-Anesthetics Flashcards
Anesthesia is defined as a state of ______, _____ loss of _______ or ______
that is induced for medical purposes.
controlled, temporary, sensation, awareness
In what situations is anesthesia used?
It is used daily in most veterinary practices to provide
* For diverse range of indications including
Sedation
Tranquilization
Immobility (very important)
Muscle relaxation
Unconsciousness
Pain control
What indications is anesthesia used for?
Surgery
Dentistry
Grooming
Diagnostic imaging
Wound care
Capture/transport of wild animals
What is difference between being
1. Fully conscious
2. Unconscious
3. Sedated
4. General Anesthesia
Fully conscious: patient is awake but under sedation (light, moderate, or deep).
Unconsciousness: general anesthesia –> light, moderate, deep, ___.
Define local anesthesia. Provide examples.
Is the patient awake or asleep?
Local anesthesia: numbs a small section of the body. Examples: cataract
surgery, a dental procedure or skin biopsy.
Patient is awake during the procedure.
Define regional anesthesia
Provide examples.
Is the patient awake or asleep?
Regional anesthesia: blocks pain in a larger part of the body. Examples:
an epidural, a spinal for hip or knee surgery, or an arm block for hand surgery. Patient can be conscious during the procedure, or have sedation
Define general anesthesia
Provide examples.
Is the patient awake or asleep?
General anesthesia: makes you unconscious and insensitive to pain or any other stimuli. General anesthesia is used for more invasive surgical
procedures, or procedures of the head, chest, or abdomen.
Patient is not awake.
Define sedation
Provide examples.
Is the patient awake or asleep?
Sedation: relaxes to the point where patient can be easily aroused or awakened. Much easier than anesthesia.
Different anesthetic procedures for patients based on preexisting conditions:
Type of surgery
Age of the animal
Financial situation of the owner b/c it is expensive.
Describe stage 1 of Anaesthesia.
Stage 1 of anesthesia is Analgesia. It is characterized by Disorientation in humans,
in pets – sometimes not obvious.
Analgesia without amnesia (loss of memory).
Describe stage 2 of anesthesia.
Stage 2 is called excitement
The goal of stage 2 of anesthesia is to move through this stage as rapidly as possible. Nausea, vomiting, hyperactivity, and irregular respiration can occur in this stage.
Animals should fast before surgery. Vomiting –> chance of aspirating
Describe stage 3 of anesthesia.
Stage 3 is called surgical anesthesia
The goal of this stage is muscle relaxation, complete loss of pain sensation. Characterized by sleep, normal respiration, and blood pressure.
Describe stage 4 of anesthesia.
Stage 4 is called medullary depression.
If a patient is too deep at this is considered an anesthetic crisis.
During this stage vasomotor and respiratory centers are depressed –> can lead to coma and death. This stage is also called anesthetic crisis.
An Anesthetic is a drug used to induce a loss of ______ with or without ______
sensation, unconsciousness
Adjunct is a drug that is not a ____ anesthetic, but that is used during anesthesia to produce other desired effects such as ?
true, sedation, muscle relaxation, analgesia, reversal, neuromuscular blockade,
or parasympathetic blockade
Explain the anesthetic drug policy.
Policy:
* The anesthetic protocol, dose, and route are chosen by the Veterinarian
* Many clinics have a routine protocol, but it is important to consider all aspects of the patient’s minimum database (clinical history, age, etc).
When are pre-anesthetic medications used?
Used prior to the administration of an anesthetic agent to make anesthesia safe and
more agreeable to the patient.
What are pre-anesthetic medications used for?
Used:
* For sedation, to reduce anxiety (benzos come in here) and apprehension
* To obtain an additive or synergistic effect so that induction could be smooth and rapid.
* To counteract certain adverse effects of anesthetic drug.
* To relieve from pain (analgesia).
What are the routes of administration for pre-anesthetic medications?
Routes of administration:
* SC: slowest onset, longest duration
* IM: faster onset, shorter duration
* IV: fastest onset, shortest duration
What are the effects of pre-anesthetic medications and adjuncts?
- Calm and sedate excited animal
- Minimize adverse drug effects
- Reduce dose of concurrent drugs
- Smoother anesthetic induction and recovery
- Provide Analgesia
- Muscle relaxation
Opioids provide?
analgesia
Tranquilizers provide?
provide pre-operative sedation and amnesia and help to prevent or counteract the CNS
stimulation caused by some anesthetics.
Central muscle relaxants provide?
muscle relaxation during anesthesia
Anticholinergic agents prevent?
profuse salivation and bradycardia
Pre-anesthetic medications generally include combinations of
drugs from multiple categories:
Opioids (Morphine)
Phenothiazine tranquilizers (Acepromazine) pathway they travel down? Dopaminic
Benzodiazepines (Diazepam) pathway = GABA
α2-Agonists (Xylazine)
Anticholinergics (Atropine)
Muscle relaxants (Baclofen)
What pathway do tranquilizers travel down?
Dopaminic