Flashcards in Test 2 Notes: Janet Deck (205):
Why is species important when administering different medications & dosages?
Cats can be sensitive to medicines that are normally fine for dogs
Smaller animals need different dosages than larger animals
2 Breed complications during anesthesia
Brachycepahlics tend to get airway obstructions during recovery due to:
Sight hounds are sensitive to barbituates during recovery due to their lack of fat
(barbituates need fat to metabolize)
How should obese patients be dosed?
by their ideal weight -most drugs are dosed according to brain size, not weight
How should emaciated patients be dosed?
by their true weight -these patients are prone to hypothermia and hypoglycemia so a quick recovery is ideal, may need to add dextrose to fluids to prevent hypoglycemia
Geriatric patients are prone to ____
Early, sub-clinical renal failure & hypothermia
always use IV fluids!
Why is it important to have IV fluids running on a patient?
Functional nephrons need good renal perfusion (Blood pressure and volume)
IV fluids keep the nephrons functional and prevent renal failure in the long run
Both geriatric and young animals ideally need what kind of drugs during anesthesia?
If a female is in heat during a spay what could happen?
Hemorrhage risk is increased due to increased blood flow and bigger arteries around uterus
Why would pregnant spays be an increased risk?
The patient will be dehydrated due to the removal of the fetuses and all of the enzymes and fluids she was providing for them. Give bolus of fluids
Aggressive patients are at a higher risk due to ____
Lack of ability to get PA information
Why is knowing how long the surgery will be important?
So you know when to turn down the anesthetic %
Liver and Kidney problems could be and issue with anesthesia due to ____
Decreased metabolism- would have trouble excreting the drug
loss of electrolytes
What type of drug do you avoid if you have a patient with a history of seizures? and why?
They have a lower seizure threshold
What two specific drugs should be avoided for epileptic dogs?
Ketamine & Acepromazine (Use Valium instead)
Hyperthyroidism in cats causes ____ during anesthesia
Increased heart rate
Why is it important to know if the patient is currently on any other drugs?
Not all drugs work well together and may produce adverse side effects
Anesthesia history would be beneficial to have because ____
You can see if the patient had any previous complications or allergies
How long should you withhold food & water before PA drugs are given?
8-12 hours for food, water is okay up until PA drugs are given
Why is food withheld before a anesthesia procedure?
Most anesthetic drugs will cause vomiting which could lead to aspiration
Normal patient temp.
101.5 +/- 1degreeF
15-30rpm in dogs
20-30rpm in cats
Fever may indicate ___ which may worsen following anesthesia due to ____
stress and immunosuppression
Hypothermia ____ the effects of anesthesia, so ___
Less drugs are needed
Delay in wound healing
Longer clotting times
Normal heart rate in dogs and cats and what spot is used to get this?
60-160 (up to 180 in toy breeds and 220 in puppies)
110-220 in cats
Cachexia means ____
S&S or S&R stand for
Strong and Synchronous
Strong and Regular
What is evaluated when palpating a pulse?
rate and character
A weak or absent pulse may indicate ____
A bounding pulse may indicate ____
What could auscultating the heart help you find?
The rate and rhythm
Could hear respiratory sinus arrhythmia (normal in dogs)
Cardiac murmurs (fast-slow-fast-slow: matches respirations)
2 Main reasons for increased CRT and pale MM color
Decreased Tissue Perfusion
Examples of Peripheral Vasoconstriction causes
Alpha-2 agonists (sedatives)
Causes of Cyanosis and why this is a result
Because there is an increase in the amount of unsaturated hemoglobin
Things to look at when evaluating the pulmonary system
Respiratory rate, depth and effort
Auscultation of breath sounds
What is important to know when evaluating neuro system?
History of seizures--avoid epileptogenic agents--use Valium= tranquilizer + anticonvulsant
Pupillary light reflex--both eyes should constrict
Hepatic function is important during anesthesia for ____
Metabolism and elimination of drugs
May effect other body systems
Renal function is important during anesthesia for ____
Sign of abnormal renal function
Things to evaluate when checking GI system
Do they have any:
V/D-- dehydration & electrolyte imbalances
Parasites-- anemia, diarrhea
GDV-- impairs ventilation, decreased cardiac output, hypovolemic shock, ^^^RISK!
Ascites-- fluid in abdomen, could indicate liver dz. or heart failure
What are the bare minimum lab tests that should be run? What tube should be used?
PCV & TP
What does the PCV evaluate for?
Oxygen carrying capacity
If your patient is dehydrated the PCV will have a ____ & if they are over-hydrated the PCV will have a
TP evaluates for ____
Increased TP would indicate
Decreased TP could indicate ____
When there is blood loss and acute hemorrhage what will drop first?
TP, PCV will be normal ~12 hours post blood loss
CBC consists of what tests, and what will they evaluate?
RBC/Hct/Hgb= oxygen carrying capacity
WBC= leukocytosis (infection/stress) leukopenia (immunosuppression/viral infection)
The PA panel usually includes what 4 things?
3. ALT/alk phos
pancreatic function test (DM)
could be stress induced
How to differ between DM and stress induced glucose in urine
Urine test to check for ^ GLU
Kidney function (glomerular filtration of kidney)
When will glomerular filtration of the kidney be increased?
When the animal is:
or Impaired renal function
ALT= hepatocyte damage or destruction
Alk phos= hepatobiliary obstruction or bone growth/injury
What is the liver specific enzyme in dogs and cats?
Normal electrolyte balance is important for _____
Normal physiologic function
Blood gas tests are more important in what species?
Urinalysis consists of ____
USG-- renal tubular function
Dipsticks-- pH, blood, bilirubin, GLU
Sediment-- crystals (ethylene glycol/ammonium biurate)
What are 2 additional tests that may be run
ECG -- known heart dz.
Rads -- fractures, thorax, abdomen
4 reasons why placing a patient on a IVC is beneficial
1. easier to admin. IV induction agents (titrate)
2. can use CRI of anesthetics/analgesics
3. important if emergency drugs are needed
4. IV fluids
2 Reasons IV fluids are highly recommended
To maintain blood volume and support blood pressure
When would you DEFINITELY want IV fluids hooked up?
If the sx will result in significant blood loss
Patient is dehydrated
Animal is at risk for hypotension or shock
Class I anesthetic risk
Excellent anesthetic risk
Normal healthy patient getting a elective procedure only (OHE, Declaw, Neuter)
Class II anesthetic risk
Good anesthetic risk
Patient with slight to mild systemic disease
Well controlled disease of ONE body system
Neonatal or Geriatric
Mild to Mod obese
Class III anesthetic risk
Fair anesthetic risk
Moderate systemic disease
Mild clinical signs
Controlled dz of 1 or more body systems
Low to moderate fever
Heart or renal disease
Class IV anesthetic risk
Poor anesthetic risk
Severe systemic disease that is a threat to life
At least 1 poorly controlled severe disease
*Sx must be preformed to save life*
Class V anesthetic risk
Guarded anesthetic risk
Moribund (close to death)
Patient not expected to survive 24 hours with or without surgery
Sx preformed in desperation
Not expected to survive
What are some myths of pain in animals?
Animals don't perceive pain like people- they tolerate it better than humans
Owners won't pay for analgesics
Better to keep animals in pain so they won't ruin the sx. site
Biology/physiology of pain
Increased anxiety and stress
Affects endocrine system
Decreased immune function
Signs that animal is in pain
Body posture- hunched over/abnormal
Activity- restless/not moving
What are the first 4 vital signs?
What is the wind-up effect?
Hyper-excitability of central neurons due to constant bombardment of pain signals -- will wake up with overwhelming pain sensation, harder to control.
Why should pre-emptive analgesics be used?
Decreases the wind-up effect
Decreases the amount of GA needed
What 2 things does the wind-up effect lead to?
Pain caused by a stimulus that normally does not result in pain
increased response to a painful stimulus
What do opioids act on?
receptors in the brain and spinal cord
may also provide some sedation
Butorphanol- cheek pouch in cats
Routes of administration for Opioids
IM & SQ
Epidural duration of action
Most commonly morphine
Provides 6-24 hours of analgesia to caudal thorax, abdomen, hind limbs, pelvis, and tail
3 Properties of NSAIDs
3. Anti-Pyretic (decreases fever)
2 Types of NSAID analgesia
Visceral (soft tissues/organs)
NSAIDs cause inhibition of ____
What 2 enzymes are inhibited by NSAIDs?
COX1 & COX2 (important in production of prostaglandins)
COX1 produces ____ prostaglandins & maintain what 3 things?
Renal blood flow
Production of gastric mucus
What can inhibition of the COX1 enzyme lead to?
COX2 enzymes produce prostaglandins that cause what 2 things?
What are some examples of NSAIDs?
What are some examples of Opioids?
What is the shortest acting Opioid?
What are 3 NSAIDs not typically used in animals due to toxicity?
How long does injectable carprofen usually last?
24 hours of analgesia
What are 4 side effects of NSAIDs
Impaired platelet function
Hepatic damage (from long term use)
If you are worried about an animal's liver before giving NSAIDs what test should you do?
Bile acids test to assess hepatic function
(fast animal, test, feed animal, and test again)
What do local anesthetics do?
Block sensory nerve impulses and transmission of pain impulses
Temporary loss of sensation
What are 4 benefits of local anesthetics?
Few cardiovascular side effects
Good pain control
Minimal patient recovery
Why would local anesthetics be used with GA?
Not as much GA gasses are needed
Pain control during and after surgery
Topical local anesthetics normally come in an ____ and can be used to ____
Decrease laryngospasms when intubating a cat
"Splash block" by applying directly on nerves during sx.
How are infiltration local anesthetics used?
By blocking the nerves on the incision site
Ring block for a Onychectomy
What does a direct nerve block do?
Targets specific nerves
Can be used for dental blocks,onychectomies, brachial plexus blocks, enucleation sx
MLK & benefit of this drug combo
Morphine Lidocaine Ketamine
IV Local anesthetic
Reduces inhalant anesth. requirements by 25-30%
Fentanyl Lidocaine Ketamine
Produces analgesia, but no anesthetic effect
Apply at surgery site
Example of IV local anesthetics and benefits
CRI of Lidocaine
Decreased vaporizer settings
Increases GI motility (horses)
Where do you inject an epidural?
Into lumbosacral region
What does local epidural do?
Loss of sensation and motor function
What does a opioid epidural do?
Use for pain control post-op
4 examples of local anesthetics
What does adding epinephrine to local anesthetics do?
Causes vasoconstriction so local is not absorbed into the blood stream, and can increase the duration by 50%
What are some negative aspects of local anesthetics
Lidocaine toxicity- neurotoxicity
Lidocaine CRI in cats- can cause seizures and bradycardia
Bupivicaine- Never IV
Alpha 2 agonists are ____ & are _____ than analgesia
What do Alpha-2 agonists act on?
Pain receptors in brain & spinal cord to diminish pain perception
Examples of Alpha-2 agonists
How are Alpha-2 agonists reversed?
With Alpha-2 antagonists
Ketamine is a ____/____
When is Ketamine commonly used?
For induction of anesthesia or as GA for short procedures (Does NOT create unconsciousness)
What are NMDA receptors?
Pain receptors in the spinal cord
Why would a NMDA antagonist be used?
To prevent a wind up effect
What are some non-pharmacologic methods of pain control?
What 2 things can amplify pain and how is this prevented?
Anxiety & Fear
Sedatives and Tranquilizers can help calm the patient
What are 5 reasons why we use PA drugs?
1. Sedate/Tranquilize- calms, decreases stress, and muscle relaxation
2. Pre-emtive analgesia to prevent wind up
3. Prevent bradycardia, dry secretions
4. Decrease amount of GA needed
5. Safer and smoother induction & recovery
How are PA drugs given?
IM or SQ
IV for Diazepam or emergency drugs
What are 5 classifications of routine Pas?
Alpha-2 agonists (sedatives)
What are the 2 Anticholinergics?
Atropine sulfate (Atropine)
How do Anticholinergics work?
Against the cholinergic (parasympathetic) nervous system
Block function of acetylcholine and vagal nerve
What are the main effects of anticholinergics?
slured<3= Heart- prevents bradycardia or may increase rate
What is the MAIN reason for using an anticholinergic?
to prevent bradycardia
What is the duration of Atropine sulfate?
Which anticholinergic has a faster onset and increases the HR more?
Which anticholinergic prevents bradycardia, without the risk of causing tachycardia?
Glycopyrrolate- milder on the heart than atropine
Which anticholinergic has a longer duration of action?
When would you NOT use an anticholinergic?
CHF or Hyperthyroidism
What are the 2 groups of Tranquilizers?
What is the 1 Phenothiazine Tranquilizer?
What are the 3 Benzodiazapine Tranquilizers?
Zolezapam (in Telazol)
What are some physical properties of Acepromazine?
10mg/ml concentration (usually diluted to 1mg/ml)
How long do Phenothiazines last?
4-8 hours, sedation can last 24 hours
24-48 hours in geriatric or neonates
What are 10 effects of Phenothiazines?
**Antiemetic (decreased V/D)
Antihistamine (dont use in animals getting allergy test)
**Vasodilation**- can cause profound hypotension and hypothermia
Prolapse of 3rd eyelid (Ace face)
Penile prolapse in horses
May lower seizure threshold
NO analgesia but can improve analgesic effects
Dysphoria in some cases
What is the maximum dose of Acepromazine?
What is the reversal agent for Benzodiazepines?
What are some physical properties of Benzodiazepines?
Diazepam is NOT water soluble
(can only be mixed with Ketamine)
NO analgesic properties
Controlled -human abuse potential
What are some main effects of Benzodiazepines?
**Anti-anxiety and calming**
not as much CNS as Ace- appear calm, but still alert
Excitement instead of calming in some cases (works best when combined with other drugs)
What combination works best together to prevent excitement instead of calming?
Opioid & Benzodiazepines (tranquilizer)
Other effects of Benzodiazepines
Good skeletal muscle relaxation (counteracts muscle rigidity caused by Ketamine)
Anticonvulsant - good for PA patients with seizure disorders
Behavior modification: (oral diazepam)- aggression, anxiety, marking, licking
Which group of tranquilizers has minimal adverse side effects?
How should Diazepam be given?
In combination with other drugs as PA
May cause excitement if given alone
Water soluble- can mix with other PA drugs
Given IM or SQ
Minimal sedation and possible excitement if used alone (use in combo)
found in (Telazol)
Can be used as induction agent or sole anesthetic agent for short, minimally painful procedures
What 2 drugs are in Telazol?
Zolazepam & Tiletimine
What are the 3 Alpha-2 agonists?
What is Xylazine reversed with?
Yohimbine alpha-2 antagonist (Yobine)
What are Dexmedetomidine and Medetomidine reversed with?
Atipamezole alpha-2 antagonist (Antisedan)
Properties of Alpha-2 agonists (sedatives)
Can be absorbed through skin & mm
Produce analgesia, sedation, muscle relaxation
Emetic- vomiting in 50% of dogs and 90% cats
How do Alpha-2 agonists (sedatives) work?
By binding to alpha-2 adrenoreceptors on sympathetic nerves within brain and spinal cord
Which group of drugs produces a potent, sleep-like state?
Does sedation or analgesia last longer in alpha-2 agonists?
How can alpha-2 agonists be given?
IV, IM, SQ, Epidural
Side effects of alpha-2 agonists
**Bradycardia and arrhythmias
Only used in young, healthy animals
Only used in young, healthy, calm animals
Bradycardia is common
How is Medetomidine and Dexmedetomidine dosed?
By mcg per square meter of body surface (use chart for volume using body weight)
Newer version of Medetomidine (Domitor)
Adverse reaction in excited animals
Use only in young, healthy and calm patients
What should be given before administration of alpha-2 sedatives?
Anticholinergics to decrease adverse cardio effects
What group of drugs are the most effective for treatment of pain?
How are Opioids used?
For PA- decrease GA and windup
What are the 3 classifications of Opioids and which is the best?
What are the 2 Opioid receptors in the brain?
What are the 5 Pure agonist Opioids?
What is the 1 mixed agonist/antagonist opioid?
What is the 1 partial agonist opioid?
What is the reversal of Pure Agonist Opioids?
What are some CNS effects of Opioids?
CNS depression or excitement (dysphoria)
Euphoria in some patients (Cats love buprenorphine)
What are some signs of dysphoria?
Whining, barking, anxiety, restlessness
Analgesic effects of Opioids?
Most effective as pure agonists
Excellent PA for animals having painful surgery
What is the most common side effect of Opioids?
can be serious
dose related- smaller doses are much safer
What are a few GI side effects of Opioids and what drug can be used to decrease these?
Atropine or Acepromazine decreases these effects
Dogs get ___ and ___thermia with Opioids
Cats get ___ and ___thermia with Opioids
Miosis & Hypothermia
Mydriasis & Hyperthermia
Can cause dysphoria
Best when used with tranquilizer
What 2 things does Morphine produce?
Analgesia & Sedation
What are some benefits of Morphine?
Inexpensive and effective for severe pain
Can be added to fluids and given IV
Routes and duration of Morphine?
IM, SQ, IV (dogs only) Epidural
Epidural- 12-24 hours
IM or SQ- 4+ hours in cats (less chance of bad reaction SQ)
5X more potent than morphine
IV, SQ, or IM in both cats and dogs
Duration of Hydromorphone
Lasts 4 hours (IM,SQ)
Effects of Hydromorphone
Less likely to cause vomiting
Less potential to cause excitement in cats
10X more potent than morphine and more sedation
Duration and effects of Oxymorphone
Less likely to cause vomiting
More expensive than morphine and hydro
Increased sensitivity to sound
100-150X more potent than morphine
Who is fentanyl not recommended in?
Duration of fentanyl
Only 30min. so commonly used as CRI or Transdermal patch
Fentanyl patch brand name & facts
Transdermal delivery that provides continuous, steady-state analgesia for 3-5 days (Post op)
How long does it take the Fentanyl patch to reach therapeutic blood levels?
4-12 hours in cats
12-24 hours in dogs
Apply patch 12-24 hours prior to anesthesia
(Torbugesic or Torbutrol)
Not as effective as pure is at treatment of severe pain
What can Butorphanol reverse?
(Torbugesic or Torbutrol)
Partially reverses pure agonists- can use to somewhat reverse resp. depression, sedation, or dysphoria but also reverses some analgesic effects.
Duration of Butorphanol
(Torbugesic or Torbutrol)
1 hour in dogs
Up to 4 hours in Cats
Analgesia for mild to moderate pain
Has the longest duration
Duration of Buprenorphine
Lasts 6-8 hours and up to 12 in some patients
Which opioid has a better analgesia for cats that is administered OTM?
What does OTM mean?
Cheek pouch administration in cats
What do Opioid antagonists do?
Displace opioids from receptors, causing a reversal of the agonist effect
Can reverse sedation, dysphoria, panting, resp. depression, hypotension, bradycardia...etc.
Naloxone blocks all ____ receptors
Can be titrated to minimize the reversal of analgesia
What is the elephant opioid?
3,000-8,000X more potent than morphine
Can immobilize elephants and other large mammals
Reversed with M5050