Anesthesia & Analgesia Flashcards

1
Q

In the study, “Early Analgesic Efficacy of Morphine, Butorphanol, Lidocaine, Bupivacaine, or Carprofen After Periodontal Treatment in Dogs” what were the significant values pertaining to VAS values?

A

Butorphanol had significantly lower values than saline. And bupivicaine had significantly lower values than saline and lidocaine.

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2
Q

In the study, “Early Analgesic Efficacy of Morphine, Butorphanol, Lidocaine, Bupivacaine, or Carprofen After Periodontal Treatment in Dogs” what were the significant values pertaining to UMPS values?

A

Bupivicaine had significantly lower values than saline, butorphanol and lidocaine. And carprofen had significantly lower values than lidocaine and saline.

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3
Q

In the study, “Early Analgesic Efficacy of Morphine, Butorphanol, Lidocaine, Bupivacaine, or Carprofen After Periodontal Treatment in Dogs” what were the significant values pertaining to cortisol values?

A

Lidocaine post tx had significantly higher values than saline, bupivacaine and carprofen.

Serum cortisol levels post tx were also significantly higher in lidocaine and morphine compared to pre-tx values.

Bupivacaine had lower post-tx values compared to pre-tx values.

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4
Q

In the study, “Early Analgesic Efficacy of Morphine, Butorphanol, Lidocaine, Bupivacaine, or Carprofen After Periodontal Treatment in Dogs” what were the significant values pertaining to glucose values?

A

Plasma glucose levels were significantly higher in control, morphine and lidocaine compared to pre tx values.

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5
Q

What was the main take away in the study, “Duration of Action of Bupivacaine Hydrochloride Used for Palatal Sensory Nerve Block in Infant Pigs”?

A

Bupivicaine has a relatively short and variable duration of action far below what is expected based on its pharmacokinetic properties.

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6
Q

What is MAC?

A

Minimum steady state alveolar concentration of an inhalation anesthetic required to prevent gross purposeful movement to a noxious stimulation in 50% patients

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7
Q

What was the main takeaway in the study, “Area of Desensitization Following Mental Nerve Block in Dogs”, JVD 2011.3?

A

The mental block does not reliably provide generalized desensitization to tissues of the incisive and rostral regions of the mandible.

So… then why do we use it… shrug

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8
Q

Systemic opioid adiminstration is most effective at decreasing nociceptor pain associated with what nerve fibers?

Lumb and Jones

A

C-fibers (slow-conducting, unmyelinated nerves)

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9
Q

What opioid is a partial mu agonist?

Lumb and Jones

A

Buprenorphine

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10
Q

Butorphanol is what type of opioid?

Lumb and Jones

A

Mu antagonist
Kappa agonist

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11
Q

What type of opioids cause a diuretic response?

Lumb and Jones

A

Kappa agonists

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12
Q

Which of the following is correct regarding cardiac output?
A. Bradycardia diminishes cardiac output by reducing stroke volume
B. Tachycardia diminishes cardiac output by reducing stroke volume
C. Afterload impedance to cardiac output is a common problem under GA
D. Cardiac output determines systemic vasomotor tone

Lumb and Jones

A

C. Afterload impedance to cardiac output is a common problem under GA

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13
Q

Stroke volume is determined by what two factors?

Lumb and Jones

A

Preload
Myocardial contractility

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14
Q

Cardiac output is determined by what two factors?

Lumb and Jones

A

Heart rate
Stroke volume

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15
Q

What two factors determine blood pressure?

Lumb and Jones

A

Cardiac output
Peripheral vasomotor tone

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16
Q

What is the important determinant of peripheral tissue perfusion?

Lumb and Jones

A

Peripheral vasomotor tone

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17
Q

What is the important determinant of brain and heart perfusion?

Lumb and Jones

A

Arterial blood pressure

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18
Q

What two factors determine blood oxygen content?

Lumb and Jones

A

Hemoglobin concentration
Oxygenation

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19
Q

What two factors determine oxygen delivery?

Lumb and Jones

A

Oxygen content
Cardiac output

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20
Q

What is allodynia?

A

Pain due to a stimulus which does not normally provoke pain.

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21
Q

What are three common causes of bradycarida that are not responsive to pharmacological treatment?

Lumb and Jones

A

Severe hypothermia
Cardiac conduction abnormalities
Severe myocardial hypoxemia

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22
Q

Are anticholinergics parasympatholytic or sympathomimetic?

Lumb and Jones

A

Parasympatholytic

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23
Q

What is the defintion of systolic pressure?

Lumb and Jones

A

Highest intra-arterial pressure of each cardiac cycle

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24
Q

What is mean pressure?

Lumb and Jones

A

The average of the area under th pulse pressure waveform of the measured systolic and diastolic pressure

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25
Q

What are ASA physical statuses I, II, III?

A

I: Healthy patient
II: Patient with mild systemic disease, disease process is controlled and stable, patient exercise tolerant
III: Patient with severe systemic disease, manifests with clinical signs, patient has functional limitations

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26
Q

What are ASA physical statuses IV and V?

A

IV: Patient with systemic disease that is a constant threat to life, ex congestive heart failure, septic shock, DKA
V: A moribund patient not expected to survive without the operation, ex advanced septic shock, severe head trauma

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27
Q

What are the clinical measurements of cardiac preload?

Lumb and Jones

A

End diastolic diameter on echocardiography
Chest rads: diameter of posterior vena cava
Ease of jugular vein distension

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28
Q

What is the definition of central venous pressure?

Lumb and Jones

A

Luminal pressure of the intrathoracic vena cava

Normal CVP dogs and cats 0-10cm H20

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29
Q

Positive pressure ventilation impedes what three cardiovascular components?

Lumb and Jones

A

Intrathoracic venous return
diastolic filing of the heart
Stroke volume

Clinically can see a decrease in systolic and mean blood pressure, pulse pressure, pulse quality, pulse pressure waveform

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30
Q

What pulse pressure wavefroms are associated with large and small stroke volumes?

Lumb and Jones

A

Large stroke volume: bounding pulse, tall, wide waveform
Small stroke volume: thready pulse, short, narrow waveform

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31
Q

What is the trigger for transfusion in vet med?

Lumb and Jones

A

PCV 20-25%

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32
Q

What Doppler ultrasound based measurement/calculation can be used to measure myocardial contractility?

Lumb and Jones

A

Fractional shortening

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33
Q

What physiologic conditions cause vasoconstriction?

Lumb and Jones

A

Hypovolemia
Heart failure
Hypothermia

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34
Q

The venous-arterial PCO2 gradient increases as hypo or hypervolemia increases

A

As hypovolemia increases

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35
Q

Lactate is a measure of what?

Lumb and Jones

A

Poor tissue perfusion

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36
Q

Lactate is not as sensitive for detection of O2 deficiency in what tissues

Lumb and Jones

A

Tissues with low mass but high oxygen demand: brain, kidney

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37
Q

What measurements on blood gas increase with increasingly severe hypovolemia?

Lumb and Jones

A

Base deficit
Arterial-venous pH gradient

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38
Q

What is apneustic breathing and what drug is it associated with?

Lumb and Jones

A

Inspiratory hold
ketamine

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39
Q

What does arterial PaCO2 measure and what are normal values?

Lumb and Jones

A

Measure of effective alveolar minute ventilation
35-45mmHg

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40
Q

Venous PCO2 is usually how much higher than PaCO2?

Lumb and Jones

A

3-6mmHg higher than PaCO2

Can be used as a surrogate marker for PaCO2

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41
Q

An increased arterial-venous PCO2 gradient suggests what in terms of tissue perfusion?

Lumb and Jones

A

Decreased tissue perfusion

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42
Q

Is time or volume capnography used in clinical practice?

Lumb and Jones

A

Time capnography

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43
Q

What are normal PaO2 levels awake and during anesthesia?

Lumb and Jones

A

Normal at sea level (21%) O2: 80-110mmHg
PaO2> 110mmHg normal while under anesthesia

Due to breathing oxygen-enriched gas mixtures

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44
Q

How would you troubleshoot the following capnograph?

A

There is a slant to the upstroke portion of the expiratory phase of the breathing cycle - this may indicate a kinked endotracheal tube, an obstructed endotracheal tube, partial airway obstruction or bronchospasm.

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45
Q

How would you troubleshoot the following capnograph?

A

The baseline is not returning to zero, there may be exhausted CO2 absorbing granules, incompetent or absent unidirectional valves, decreased oxygen flow rate in a non-rebreathing circuit, or damaged non-rebreathing circuits.

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46
Q

How would you troubleshoot the following capnograph?

A

There is no plateau or an abnormal downstroke present on inhalation –> check the endotracheal tube cuff!

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47
Q

How would you troubleshoot the following capnograph?

A

If the capnograph is reading 0, check for apnea, cardiac arrest, airway obstruction, esophageal intubation, or a patient disconnect from the anesthesia circuit.

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48
Q

What is nociception?

A

Nociception is defined as the processing of a noxious stimulus resulting in the perception of pain by the brain.

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49
Q

What are the components of nociception?

A

Transduction, transmission, and modulation

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50
Q

What is transduction?

A

Transduction is the conversion of a noxious stimulus (mechanical, chemical or thermal) into electrical energy by a peripheral nociceptor (free afferent nerve ending).

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51
Q

What is transmission?

A

Transmission involves impulse propagation from the site of oral injury primarily through the trigeminal afferent nerves.

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52
Q

What is modulation?

A

This occurs when neurons from fibers in the oral cavity synapse with nociceptive-specific and wide dynamic range neurons in the nucleus caudalis located in the medulla.

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53
Q

What neuropeptides facilitate the pain signals by binding to their receptors?

A

Substance P and glutamate

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54
Q

What is primary hyperalgesia?

A

An increased sensitivity within the injured area predominantly due to peripheral nociceptor sensitization.

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55
Q

x

What is secondary hyperalgesia?

A

Pain sensitivity that occurs in surrounding undamaged tissues.

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56
Q

What is wind up pain or central sensitization?

A

When peripheral sensitization remains untreated, the neurons that are subjected to repeat or high-intensity nociceptive impulses become progressively and increasingly excitable even after the stimulus is released.

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57
Q

What is an effective way of managing wind up pain??

A

Administering drugs that bind to the NMDA receptor so that glutamate cannot do so.

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58
Q

Local anesthetics block what pathways in nociception?

A

transduction, transmission modulation, and projection

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59
Q

What drug classes are known to affect the pain transduction pathway (peripheral sensitization inhibition)?

A

Local anesthetics, opiods,NSAIDS and corticosteroids

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60
Q

What drug classes will affect modulation (central sensitization inhibition)?

A

Local anesthetics, alpha 2 agonists, opioids, tricyclic antidepressants, cholinesterase inhibitors, NMDA antagonists, NSAID’s and anticonvulsants

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61
Q

What drug classes affect transmission (impulse conduction inhibition)?

A

Local anesthetics, alpha 2 agonists

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62
Q

Where are opioid receptors found?

A

The central and peripheral nervous system

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63
Q

What is the time of onset for fentanyl patches in dogs and cats respectively?

A

Dogs: 18-24 hours
Cats: 6-12 hours

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64
Q

What are examples of pure agonist opiods?

A

Morphine, hydromorphone, and fentanyl

65
Q

What are examples of partial agonist opiods?

A

Buprenorphine and butorphanol

66
Q

How are prostaglandins produced?

A

By the breakdown of arachidonic acid by COX enzymes that are released from various cell types at the site of tissue injury.

67
Q

What is the reversal. For alpha 2 agonists?

A

Atipamezole

68
Q

What are side effects of alpha 2 agonists like medetomidine and xylazine?

A

Sedation, analgesia, increased systemic vascular resistance, bradycardia, respiratory depression and vomiting

69
Q

True or False: The use of an anti cholinergic like atropine is safe to use in combination with an alpha-2 agonist to offset bradycardia.

A

False, this is very controversial, and may result in cardiac compromise.

70
Q

Describe the MOA of ketamine.

A

It is an NMDA antagonist.

71
Q

Describe the MOA of tramadol and list what medications should not be used concurrently with this medication.

A

MOA - It is a reuptake inhibitor of serotonin and norepinephrine. It also possesses weak mu agonist characteristics. It should not be used with tricyclic antidepressants, SSRI’s or mono amine oxidase inhibitors due to risk of serotonin syndrome.

72
Q

The pulse oximeter SpO2 is a surrogate marker of what physiologic parameter?

Lumb and Jones

A

Hemoglobin saturation with oxygen (SaO2)

73
Q

At what SpO2 is the patient considered hypoxemic?

Lumb and Jones

A

Hypoxemia < 95%

Severe hypoxemia < 90%

74
Q

What two wavelengths of light does pulse oximetry used?

Lumb and Jones

A

660-940nm

75
Q

What are the categorical casues of hypoxemia?

Lumb and Jones

A

Low inspired oxygen
Hypoventilation
Venous admixture

Venous admixture: low ventilation/perfusion regions, atelectasis, diffusion defects, right ot left shunts

76
Q

What is the lowest body temperature not associated with detrimental effects?

Lumb and Jones

A

96F

77
Q

What body temperatures can cause ventricular fibrillation?

Lumb and Jones

A

72-74F

78
Q

What body temperatures cause marked CNS depression?

Lumb and Jones

A

82-86F

Shivering will not occur → require artificial rewarming
Atrial arrhythmias may occur, O2 consumption reduced to 50%, heart rate + cardiac output about 35-40% of normal, arterial blood pressure to about 60%, cerebral metabolism ~25%

79
Q

Cell damage starts at what hyperthermic temperature?

Lumb and Jones

A

> 108F

Oxygen delivery can no longer keep up with incr metabolism and O2 consumption

80
Q

What is the MOA of malignant hyperthermia?

Lumb and Jones

A

metabolic heat production of disturbed intracellular calcium cycling +/- muscle hypertonicity

81
Q

What is the definition of potency?

Lumb and Jones

A

the relative dose needed to elicit a response

Not related to duration of effect or efficacy

82
Q

Why do dogs with an MDR1 mutation overdose?

Lumb and Jones

A

They do not have a functional efflux pump (P-glycoprotein efflux pump) which transports drugs out of CNS

83
Q

Phenothiazine drugs affect what receptors?

Lumb and Jones

A

Adrenergic
Muscarinic
Dopaminergic serotonergic
Histamine

84
Q

In Gruenheid’s 2018 study “Risk of anesthesia-related complications in brachycephalic dogs,” brachycephalic dogs were at a higher risk of experiencing complications in what anesthetic time periods?

JAVMA 2018

A

Peri and postanesthetic complications brachys higher risk

85
Q

In Gruenheid’s 2018 study “Risk of anesthesia-related complications in brachycephalic dogs,” what factors were associated with a higher perianesthetic complication rate?

JAVMA 2018

A

Brachycephalic status
Longer duration of anesthesia

Risk decreased with increasing body weight and with orthopedic or radiologic procedures

86
Q

In Gruenheid’s 2018 study “Risk of anesthesia-related complications in brachycephalic dogs,” what factors were associated with a higher postanesthetic complication rate?

JAVMA 2018

A

Brachycephalic status
Increasing ASA status
Use of ketamine plus benzodiazepine for anesthetic inductive
Invasive procedures

87
Q

How do NSAIDs produce analgesia?

Rauser. Early Analgesic Efficacy of Morphine, Butorphanol, Lidocaine, Bupivacaine or Carprofen After Periodontal Treatment in Dogs. JVD 2020.

A

Inhibit cyclooxygenase enzyme in target tissue
Suppress pain transmission peripherally and centrally by blocking neuronal plasticity and central sensitization

88
Q

What are the effects of inhibition of COX-1 and COX-2 on pain and inflammation?

Rauser. Early Analgesic Efficacy of Morphine, Butorphanol, Lidocaine, Bupivacaine or Carprofen After Periodontal Treatment in Dogs. JVD 2020.

A

inhibition of COX-1 and COX-2 prevents these enzymes from breaking down arachidonic acid and producing prostaglandins which perpetuate inflammation and sensitize neurons to chemical, mechanical and thermal stimuli

89
Q

What is the mechanism of action of local anesthetics?

Rauser. Early Analgesic Efficacy of Morphine, Butorphanol, Lidocaine, Bupivacaine or Carprofen After Periodontal Treatment in Dogs. JVD 2020.

A

Act on sodium channels of nociceptive fibers by blocking influx and preventing generation of an action potential and its propagation to the spinal cord

90
Q

What are the max doses of lidocaine and bupivacaine in dogs?

Rauser. Early Analgesic Efficacy of Morphine, Butorphanol, Lidocaine, Bupivacaine or Carprofen After Periodontal Treatment in Dogs. JVD 2020.

A

Lidocaine 4-6mg/kg
Bupivacaine 2mg/kg

91
Q

In Rauser’s 2020 study “Early Analgesic Efficacy of Morphine, Butorphanol, Lidocaine, Bupivacaine or Carprofen After Periodontal Treatment in Dogs,” what was the methods used?

JVD 2020

A

84 client owned dogs with PD1 or PD2 that needed RP/C divided into 6 treatment groups:
Butorphanol (on induction), Morphine (on induction), Carprofen (on induction), lidocaine local block, bupivacaine local block, saline as control (on induction)

Scored with Visual Analog Scale for pain (VAS) and the modified University of Melbourne Pain Score (UMPS)
Blood glucose and cortisol measured prior to analgesic administration and 2 hours later

92
Q

In Rauser’s 2020 study “Early Analgesic Efficacy of Morphine, Butorphanol, Lidocaine, Bupivacaine or Carprofen After Periodontal Treatment in Dogs,” what treatments were concluded to be superior to the others?

JVD 2020

A

Carprofen on induction, bupivacaine nerve block

93
Q

In Rauser’s 2020 study “Early Analgesic Efficacy of Morphine, Butorphanol, Lidocaine, Bupivacaine or Carprofen After Periodontal Treatment in Dogs,” bupivacaine and carprofen each had lower pain scores than what treatments respectively?

JVD 2020

A

Bupivacaine: lower than saline, butorphanol, lidocaine
Carprofen: lower than saline and lidocaine

94
Q

In Holman’s 2014 paper “Duration of Action of Bupivacaine Hydrochloride Used for Palatal Sensory Nerve Block in Infant Pigs,” what duration of action of bupivacaine was found?

A

1-3 hours

shorter than previous studies which may be due to neonatal pig model

95
Q

What is the definition of minimum steady state alveolar concentration (MAC)?

A

minimum steady state alveolar concentration of an inhalation anesthetic required to prevent gross purposeful movement to a noxious stimulation in 50% patients

96
Q

What are palpation landmarks for the infraorbital foramen in a horse?

A

The nasoincisive notch and the rostral border of the facial crest, midway between is the infraorbital foramen.

97
Q

In Synder and Synder’s 2016 study “Effects of Buprenorphine Added to Bupivacaine Infraorbital Nerve Blocks on Isoflurane Minimum Alveolar Concentration Using a Model for Acute Dental/Oral Surgical Pain in Dogs,” did both treatment groups (bupivacaine vs bupivacaine +buprenorphine) significantly reduce MAC?

A

Yes, no statistically significant differences between the two due to sample size

98
Q

In Synder and Synder’s 2016 study “Effects of Buprenorphine Added to Bupivacaine Infraorbital Nerve Blocks on Isoflurane Minimum Alveolar Concentration Using a Model for Acute Dental/Oral Surgical Pain in Dogs,” what percent of dogs had ~20% MAC reduction 48 hours and 96 hours post block administration for the bupivacaine vs bupivacaine vs bup groups respectively?

JVD 2016

A

Bupivacaine: 48 hrs 25%, 96 hours 0%
Bupivacaine + bup: 48hrs 50%, 96hrs 25%

99
Q

In Synder and Synder’s 2016 study “Effects of Buprenorphine Added to Bupivacaine Infraorbital Nerve Blocks on Isoflurane Minimum Alveolar Concentration Using a Model for Acute Dental/Oral Surgical Pain in Dogs,” what major conclusions were made?

JVD 2016

A

Bupivacaine as a local anesthetic may have analgesic effects for greater than 24 hours (24-72hrs)
Addition of buprenorphine may extend duration of analagesia 48-96hrs

100
Q

In Krug’s 2011 study “Area of Desensitization following Mental Nerve Block in Dogs,” unilateral mental nerve blocks were not very successful. What was the anatomic rationale for this finding?

JVD 2011

A

Collateral/redundant circulation: buccal branch of CNV innervates soft tissues; contralateral inferior alveolar nerve overlaps; CNVII may also have some sensory fibers; mylohyoid nerve (motor to digastricus) may also have sensory

101
Q

What is being depicted in this image?

A

The levator labii superioris muscle is being elevated with the operators thumb prior to inserting the needle.

102
Q

In Krug’s 2011 study “Area of Desensitization following Mental Nerve Block in Dogs,” what was cited as the minimum length of nerve desensitization needed for a successful nerve block?

JVD 2011

A

6mm of nerve (~3 nodes of Ranvier required to block saltatory transmission in myelinated nerves)

103
Q

In Krug’s 2011 study “Area of Desensitization following Mental Nerve Block in Dogs,” what was the main conclusion?

JVD 2011

A

The area of desensitized tissue was smaller than expected and highly variable so other modes of analgesia should be considered

Used 0.4ml per block

104
Q

What methods of analgesia block input to the CNS for perception of pain?

Verstraete Chp 4

A

NSAIDs (block prostaglandin production)
Stimulation of opioid receptors
Blocking alpha-1 adrenergic receptors

105
Q

In the horse where does the maxillary nerve lie?

A

Within the pterygopalatine fossa

106
Q

What analgesics reduce the result of the pain input to the CNS?

Verstraete Chp 4

A

Stimulation of opioid receptors
Alpha-2 receptors
Serotonin
NMDA antagonists

107
Q

Lidocaine CRIs have what negative cardiovascular effects in cats?

Verstraete Chp 4

A

Reduce cardiac output

108
Q

What is the definition of systolic and mean hypotension in mmHg?

Verstraete Chp 4

A

Systolic < 90mmHg
Mean < 70mmHg

109
Q

What is the recommended injection technique for the equine maxillary nerve block and describe it.

A

The extraperiorbital fat body injection technique. This infiltrates the fat body lying deep to the masseter muscle and superficial to the maxillary nerve.
Landmarks: 10 mm ventral to the facial crest from a line perpendicular to the dorsal contour of the skull and in the plane of the caudal third of the orbit. A 89 mm spinal or Tuohy needle is inserted perpendicular to the skin.

110
Q

Central venous pressure is a reflection of what physiologic parameters?

Verstraete Chp 4

A

Vascular volume
Intrathoracic pressure
Ability of right heart to pump blood forward

111
Q

What is the standard for determining efficiency of ventilation under anesthesia?

Verstraete Chp 4

A

Blood gas analysis

112
Q

What is the definition of hypoventilation in mmHg for dogs and cats respectively?

Verstraete Chp 4

A

Dogs PaCO2 > 43mmHg
Cats > 35mmHg

But no Tx until >65

113
Q

What block are they performing in the picture? And what muscle are they elevating?

A

Mental nerve block
They are elevating the levator labii inferioris to facilitate entry into the mental foramen

114
Q

When performing the equine extraoral inferior alveolar nerve block, what landmarks show you where the mandibular foramen is?

A

The white line depicts the imaginary occlusal surface of the mandibular cheek teeth. The black line depicts a line from the lateral canthus of the eye to the mandible. Where they intersect is the approximate position of the mandibular foramen.

115
Q

What are two unique characteristics of methadone?

A

NMDA receptor antagonist
Does not tend to cause vomiting

116
Q

What is the following a picture of?

A

Intraoral approach to the inferior alveolar nerve. Alligator forceps are grasping a 19-25 mm butterfly catheter and inserted into the oral mucosa overlying the rostral ramus just caudal to the mandibular third molar, at the level of the occlusal surface of the tooth (black arrow)

117
Q

What premedications should be avoided for patients with renal disease?

A

Alpha-2 agonists
Cause sig vasoconstriction and bradycardia and reduce cardiac output and renal blood flow

118
Q

What induction agent should be avoided particularly at high doses in patients with renal compromise?

A

Ketamine
In the cat it is excreted mainly throught the kidneys

119
Q

What inhalant is not recommended for patients with chronic kidney disease?

A

Sevoflurane
Produces compound called compound A that is toxic to the kidneys when in contact with CO2 absorbents

120
Q

What inhalant is contraindicated in patients with hepatic disease?

A

Halothane
Clinically significant hepatotoxicity

121
Q

What is the Cushing’s reflex

(Bradycardia hypertension)

A

Late marker of increased intra-cranial pressure where MAP increased suddenly in the face of increased ICP to maintain cranial perfusion pressure.
Baroreceptors in carotid and aortic bodies respond to acute hypertension by sig decreasing heart rate

122
Q

What are strategies to prevent increases in intracranial pressure?

A

Maintain low normal PaCO2 30-35 mmHg
Prevent significant hypoxemia
Maintain adequate MAP
Prevent significant alterations in acid-base status

123
Q

What percent of crystalloid volume will be extravasated within the first hour after administration?

A

75-90%

124
Q

What are the effects of low and high dose ketamine administration on patients with intra-disease/ increased ICP?

A

Low doses: may be beneficial since ketamine decreases NMDA receptor activation by glutamate the major excitatory neurotransmitter in the brain
High doses/induction with ketamine: should be avoided

125
Q

What is the ideal agent to maintain general anesthesia in a patient with increased ICP?

A

Propofol TIVA

126
Q

Drugs that cause vasoconstriction or vasodilation should be avoided in patients with advanced mitral valve degeneration?

A

Avoid vasoconstriction: increase in afterload increases regurgitation, can precipitate heart failure

127
Q

What is the treatment of ventricular tachycardia?

A

lidocaine bolus

128
Q

What heart rate is considered bradycardic in the dog?

A

HR < 60bpm

129
Q

How is sinus bradycardia treated?

A

Atropine/anticholinergics

130
Q

What are the characteristics of first degree AV block?

A

Prolonged P-R interval

131
Q

What are the ECG characteristics of Second degree AV block?

A

Not all P waves followed by QRS complexes

But all QRS complexes have a P wave

132
Q

What is the difference for low and high grade second degree AV block in terms of treatment?

A

Low grade AV block is atropine responsive
High grade is atropine unresponsive

133
Q

What are the characteristics of third degree AV block?

A

Slow heart rate
P wave and QRS complexes disassociated

134
Q

What is the treatment for third degree AV block?

A

Pacemaker
when complete AV dissociation present

135
Q

How are atrial fibrillation and flutter treated?

A

Rate control: Slow AV node conduction with diltiazem or beta blocker
Rhythm control: Quinidine, amiodarone, cardioversion if non-responsive

136
Q

In Kellner’s 2023 paper “Liposomal Bupivacaine in Dentistry and Oral and Maxillofacial Surgery,” how many studies showed no significant differences between bupivacaine and Nocita?

JVD 2023

A

5/12

137
Q

In Pascoe’s 2016 study “The effect of lidocaine or a lidocaine-bupivacaine mixture administered into the infraorbital canal in dogs,” the authors concluded that what teeth could be blocked with the infraorbital nerve block?

AJVR 2016

A

Canine teeth
They recommend using a different block to desensitize caudal to the canine teeth

138
Q

In the 2020 study “Anesthetic risk during subsequent anesthetic events in brachycephalic dogs that have undergone corrective airway surgery: 45 cases (2007-2019)” what was the % decrease in odds of postanesthetic period complications following brachycephalic airway corrective surgery?

JAVMA 2020

A

79%

139
Q

In the 2020 study “Postoperative regurgitation and respiratory complications in brachycephalic dogs undergoing airway surgery before and after implementation of a standardized perianesthetic protocol” what gastroprotectant drugs were used in the pre-op protocol?

JAVMA 2020

A

Famotidine and metoclopromide

140
Q

In Costa’s 2020 study “Postoperative regurgitation and respiratory complications in brachycephalic dogs undergoing airway surgery before and after implementation of a standardized perianesthetic protocol,” the implemented perianesthetic protocol included what?

JAVMA 2020

A

Preoperative metoclopramide and famotidine
Restrictive use of opioids
Recovery of patients in ICU

141
Q

In Costa’s 2020 study “Postoperative regurgitation and respiratory complications in brachycephalic dogs undergoing airway surgery before and after implementation of a standardized perianesthetic protocol,” what group (A: retrospective group prior to implemented changes, B: implemented changes group) had sig lower postoperative regurgitation

JAVMA 2020

A

Group B (9%)

Group A 35%

142
Q

In Davis’s 2021 study “Cadaveric Evaluation of Injectate Distribution for Two Maxillary Nerve Block Techniques in Cats,” they cite that in order to be effective what is the critical length of nerve that must circumferentially associated with an anesthetic drug to have an effective nerve block?

Hoyer, Rawlinson Frontiers 2021

A

6mm
3 nodes of Ranvier in myelinated nerves

Frog sciatic nerve model

143
Q

The sensory root of the trigeminal nerve exits the cranium from what foramen, courses through what fossa over what muscle to enter the infraorbital canal?

A

Rostral alar foramen –> pterygopalatine fossa –> medial ptyeroid muscle –> infraorbital canal

144
Q

What nerve branches exit the infraorbital nerve and maxillary nerve in the pterygopalatine fossa to innervate the caudal maxillary teeth?

A

Caudal and middle superior alveolar branches

145
Q

What techniques have been described to anesthetize the maxillary nerve in cats?

Davis “Cadaveric Evaluation of Injectate Distribution for Two Maxillary Nerve Block Techniques in Cats,” Frontiers 2021

A

Maxillary tuberosity (caudal intraoral)
Percutaneous (subzygomatic)
Infraorbital foramen

146
Q

In Davis’s 2021 study “Cadaveric Evaluation of Injectate Distribution for Two Maxillary Nerve Block Techniques in Cats,” what two techniques were compared and what volumes?

Hoyer, Rawlinson. Frontiers 2021

A

Infraorbital
Percutaneous injection technique
0.2 vs 0.4ml

147
Q

In the figure below what maxillary nerve block technique is shown and what do the black and white arrows represent?

Davis “Cadaveric Evaluation of Injectate Distribution for Two Maxillary Nerve Block Techniques in Cats,” Frontiers 2021

A

Percutaneous technique
White arrow: Maxillary foramen
Black arrows: superior alveolar foramina

148
Q

In Davis’s 2021 study “Cadaveric Evaluation of Injectate Distribution for Two Maxillary Nerve Block Techniques in Cats,” what was the difference between technique and volumes regarding circumferentially stained nerve lengths?

Frontiers 2021

A

No significant difference between techniques or volume on nerve length staining

149
Q

What is the length of feline infraorbital canal in mesaticephalic skulls?

Davis “Cadaveric Evaluation of Injectate Distribution for Two Maxillary Nerve Block Techniques in Cats,” Frontiers 2021

A

4-5mm

150
Q

In Volk’s 2019 study “Ophthalmic complications following ocular penetration during routine dentistry in 13 cats,” what percent of cats had a transoral maxillary nerve block and what percent recieved enucleation?

NZ Vet Journal 2019

A

61% (8/13) transoral
54% enucleation

151
Q

In Davis’s 2021 paper “Computed Tomography Analysis of the Feline Infraorbital Foramen and Canal,” what percent of brachycephalic skulls had redundant foramina?

Hoyer, Rawlinson. Frontiers 2021

A

67% (4/6)

152
Q

In Davis’s 2021 paper “Computed Tomography Analysis of the Feline Infraorbital Foramen and Canal,” did the length of the infraorbital canal stat sig differ between mesaticephalic and brachycephalic cats and what were the lengths?

Hoyer, Rawlinson, Frontiers 2021

A

The length did not stat sig differ
4.4-4.6mm

153
Q

In Davis’s 2021 paper “Computed Tomography Analysis of the Feline Infraorbital Foramen and Canal,” what was the relationship between the maxillary foramen to the ventral eyeball in brachycephalic vs mesaticephalic cats?

Hoyer, Rawlinson Frontiers 2021

A

Brachycephalic cats had sig shorter distance (3mm) than mesaticephalic cats (4mm)

brachycephalic cats may be at a higher risk for ocular injection than mesaticephalic cats when using the infraorbital approach due to distance from MF to eyeball

154
Q

In Davis’s 2021 paper “Computed Tomography Analysis of the Feline Infraorbital Foramen and Canal,” was significant anatomic variability identified?

Rawlinson, Hoyer. Frontiers 2021

A

Yes, particularly among brachycephalic cats

155
Q

What nerve block is being depicted in the following image?

A

Percutaneous maxillary nerve block

156
Q

What are the black arrows and white arrow pointing to in the following image?

A

Black arrows - superior alveolar foramina

White arrow - maxillary foramen

157
Q

In the study, “Inter-rate reliability of the feline grimace scale (FGS) in cats undergoing dental extractions,” what are the five action units?

A

Ear position, orbital
tightening, muzzle tension, whiskers change, and head position

158
Q

In the study, “Inter-rate reliability of the feline grimace scale (FGS) in cats undergoing dental extractions,” what was the overall takeaway?

A

Total FGS scores showed good inter-rater reliability. The FGS is a reliable tool for pain assessment in cats undergoing dental extractions. The caregiver’s presence did not affect FGS scores.

159
Q

In the JVD 2022 study, “Dental pain in cats: A prospective 6-month study” what were the Signs significantly associated with oral pain?

A

TR, missing teeth, hypersalivation