Exam 1 Flashcards
How many animals are needed to generate a reference interval?
minimum of 40 animals
Davis uses about 100
T/F: as prevalence increases, PPV increases and PVN decreases.
True
What are the perfusion parameters? (list 6)
- mentation
- mucous membrane colour
- capillary refill time
- heart rate
- pulse quality
- extremities temperature
Clinical signs associated with hypovolemia-vasoconstriction (gen. d/t decreased preload)
- obtundation
- pale mucous membranes
- slow capillary refill time
- tachycardia (cats-brady)
- poor pulse quality
- cold extremities
Clinical signs associated with vasodilation (gen. d/t decreased afterload)
- obtundation
- hyperemic mucous membranes
- very fast capillary refill time
- tachycardia
- bounding pulse quality
- warm extremities
Define: Sedation
mild to moderate depression of the CNS
Sedation vs chemical restraint
chemical restraint is just heavier sedation
Site of action for local anesthetics
- Nociceptors
- Nerves
- Spinal Cord
Site of action for general anesthetics
- spinal cord
- thalamus
- cortex
What are the two Risk Classification Schemes?
- ASA status ( only takes into account patient)
2. Operative Risk ( estimates overall risk)
T/F: Emergency surgeries have the same level of risk as elective surgeries.
False: higher mortality rates for emergency
Purpose of pre-anesthetic fasting
- reduce risk of vomiting/ regurgitation
- ruduce size of gi tract in Large Animals
Why give anesthetic pre-medication (pros and cons)?
- decrease apprehension
- provide analgesia
- reduce dose of induction and maintenance drugs
- minimize undesirable autonomic reflexes
Cons:
- takes time/ organization
- concerns about polypharmacy
Risk of mortality (during surgery) increases with:
- systemic illness
- emergency
- after hours
- lack of familiarity
Define: pain
unpleasant sensory and emotional experience associated with actual or potential tissue damage
nociception =/= pain
Pain Assessment (Physiological variables)
- not sensitive nor specific
- HR, RR, blood pressure, GI sounds
Pain Assessment (Neuroendrocrine variables)
- indicator of disease severity =/= pain
- stress hormones, endorphins, acute phase proteins
Pain Assessment (Objective Physical Measurements)
- weight and food consumption
- gait analysis
- activity level
- nociceptive threshold tests
Pain Assessment (Subjective Assessments)
use of pain scales:
- one dimensional scoring system
- multidimensional
- good for bringing attention to and documenting many different parameters
One dimensional scoring system (subjective)
- easy to sue
- not good for small changes
- high subjectivity
Multidimensional scoring system (subjective)
- behavioral +/- physiological data
- n behaviour must be known + categorized
Acepromazine (drug category, moa)
Category: phenotiazine
MOA: central dopamin receptor antagonist
Acepromazine (4 Actions)
- mild sedation (highly variable)
- decreased alertness
- anesthetic sparing
- lasts a long time (4-6 hours)(non-reversible)
Acepromazine (adverse effects)
- Vasodilation (peripheral alpha 1 antagonism)
- syncope reported in boxers
- no analgesic action
Alpha-2 Agonists (drug examples)
- dexmedetomidine
- Xylazine
- Romifidine
- Detomidine
Alpha-2 Agonists (6 Actions)
- Sedation (rousable)
- Analgesia
- Anxiolysis
- muscle relaxation
- potent drug sparing
- reversible effects
Alpha-2 Agonists (Adverse Effects)
- CV effects (initial vasoconstriction followed by decreased sympa. output)
- Diuresis, vomiting, reduced gi motility
- much more potent in cattle than horses
- sheep get pulmonary edema
Anticholinergics (dug examples, moa)
Drugs: atropine, glycopurrolate
MOA: muscarinic acetylcholine receptor antagonist (parasympatholytic)
Anticholinergics (5 Actions)
- increased HR
- bronchodilation
- decreased secretions
- decreased GI motility
- mydriasis
– no sedative or analgesic properties
Benzodiasepines (drug examples, moa)
Drugs: Diazepam, Midazolam
MOA: GABA receptor agonist
Benzodiasepines (6 Actions)
- Anxiolytic
- Amnestic
- Muscle relaxant
- Anticonvulsant
- Mild drug sparing
- Reversible
Benzodiasepines (adverse effects)
- agitation, mania, disinhibition in some healthy adults dogs/ cats
- not analgesic
- mixed resp. between young and old animals
Opioids (Mu agonist) (drugs, actions)
Drugs: morphine, oxymorphone, hydromorphone
Actions: Analgesia, Sedation (dogs, rabbits ruminants) or Euphoria (cats, horses)
Opioids (Mu agonist) (Adverse Effects)
- minimal CV effets
- resp. depression
- hot cats, cool dogs
- reversible
- variable drug sparing (dog > cat > horse)
Opioids (Mu antag/ Kappa agonist) (all)
Drugs: Butorphinol
Short duration of effect (about 1 hour)
limited analgesia + good sedation
Opioids (Mu partial agonist) (all)
Drugs: Buprenorphine
acts v similar to agonist, but with less effect for longer
high affinity for receptor = non-reversible
T/F: Therapeutic Index is a measure of drug safety (LD50/ED50) and so a higher TI means a safer drug.
True
What is the Selectivity of a drug?
the preference of a drug for its respective ligand
normally expressed as a comparison between two receptors
Potency vs Efficacy
Potency: the dose needed to create a specific effect (hig potency means lower dose for the effect)
Efficacy: the maximal effect produced
T/F: Antagonists work by producing no intrinsic activity at the target receptor.
T: A reverse agonist is different than an antagonist
Non-competitive vs competitive antagonist
Non-competitive: decreased binding affinity of agonist to R
Competitive: can overcome antagonims w/ high enough [agonist]
Effects of untreated pain?
- increased SNS activity (change in healing rate)
- decreased mobility –> muscle wasting
- splinting of chest muscles and diaphragm
- decreased GI motility and urinary retention
Non-pharmacological pain management mechanisms (7 ways)
- handling
- nursing care
- weight optimization
- warm (chronic) and cold (acute) therapy
- Acupuncture
- dress wounds
- env. modifications (ramps vs stairs)
3 Drug types for pharmacological pain management
- Opioids
- NSAIDs
- Local Anesthetics
Also, alpha-2-agonists (dex, xylazine), NMDA receptor antagonists (ketamine, amantadine), Gabapentine/ pregabalin, Tramadol
Opioids (pain management)
- moderate to severe pain
CNS: sedation in dogs -- euphoria in cats/ horses resp. depression decreased HR (vagal tone decrease) urinary retention cool dogs, hot cats
Local Anesthetics
- Lidocaine, Procaine
- reversibly block Na channels to prevent nerve trans.
- [drug] and volume affects intensity and duration of effects
Dose dependent toxicity of CNS and CV
NSAIDs
- both acute and chronic pain
- COX-1,2 inhibitors reduce prostaglandins
- not behavior modifying + oral formulations
What are the routes of administration of Opioids?
IV, IM, SQ, Topical (fentanyl patch)
What are the effects of NSAIDs
- anti-inflammatory
- anti-thrombosis
- analgesia
- anti-endotoxin
Why would you pair Xylazine (alpha 2) with morphine?
Xylazine will have synergistic effects
Indications for Ketamine, Amantadine?
- chronic pain, antihyperalgesic
Define: hernia
defect in wall of body cavity that allows protrusion of an organ or organs
Hernia anatomy
- Ring (connective tissue)
- Sac
- Contents
True vs False Hernia
True - congenital or degenerative process w/ intact hernial sac (peritoneum)
False - no hernia sac; usually acute/ traumatic
4 Causes of hernia
- congenital
- acquired/ degenerative
- traumatic
- incisional
Why treat a hernia?
- pain
- protect viscera
- adhesions
- abnormal organ fx
- strangulation, incarceration, perforation, sepsis
Incarcerations vs strangulation
Incarceration - impeded organ fx
Strangulation - impeded blood flow
Herniopathy ( 3 parts)
- reduction of contents
- repair of defect
- prevent recurrence
Oral Absorption (Cats vs Ruminants)
Cats:
- shorter GI
- intermittent eating
- slow esophageal transit time
Ruminants:
- degredation/ metabolism in rumen
- rumen dilution effects
- pH variation of rumen vs saliva