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143 Cards in this Set

  • Front
  • Back
purpose of preanaesthetic preparation (3)
identify exiting abnormalities of major organ fxn
assess severity of above
plan for appopriate anaesthetic protol that considers the patients physical status and procedure to be performed
Christinas anagram for preanaesthetic prepartion
Subjective
Objective
Assessment
Plan
how long to withhold food & water prior to anaesthetic
8-12 hours food
2-4 hours water
minimum data for preanaesthetic examination of healthy young animal
body temperature
auscultation of heart and lumgs
palpation of pulse
mm colour and CRT
PCV, TP, BUN +/- USG
options if preanaesthetic check is not within normal parameters
delay anaesthetic and retest, tx, adjust protocol, supportive care (eg IVFT)
advantages of premedication
calm patient
facilitate handling
decrease required dose of anaesthetic for induction and maintenance
provide analgesia
reduce vomiting
redce vagally or stress mediated responses (autonomic reflexes)
improve quality of recovery
less desirable aspects of a premed
delay in time to effect
cost
delayed recovery
families of premedications
anticholinergics- atropine
tranqs, sedatives
- phenothiazines
- butryophenones
-benzodiazepines
- A2 agonists
opioids
Action/ indications for atropine
anticholinergic, decreased vagal tone
prevents vagally mediated arrythmias- bradycardia, bradyarrhythmias
reduces salivation and respiratory secretions
reasons for increased vagal tone
drugs- opioids, a2 agonists, anaesthetics (reduce symp tone)
vagal reflexes during visceral manipulation
eye surgery
hypothermia
disadvantages of atropine
may cause tachy
reduces GIT motility
contraction of urinary bladder
at lower doses may cause brady, 2` heart block
causes pupilary dilation, ciliary muscle paralysis and increased intraocular pressure
contraindications of atropien
hypertrophic CM
tachy, arrythmias
hyperT
perforating eye injury
glaucoma
what are the effects of glycopyrrolate and what are its advantages
similar to atropine wiht longer duration (4 hours)
doesnt cross BBB or placental B
less likely to cause tachy
action and main properties of ACP as a premedicant
blocks dopamine and a-adrenergic receptors
1. dose dependant sedation
2, long duration sedation
3. antiarrythmic, antiemetic, antihistamine
4. potentiates opioids
disadvantages of ACP
1. lower seizure threshold
2. no analgesia
3. may decrease SBP
4. exaccerbates hypothermia- vasodilates
5. dosages need to bE reduced in debilitated or geriatric animals, those eith csrdiac or hepstic dz
at what level is an animal considered hypotensive
mean arterial pressure <60mmHG
contraindications of ACP
1. hypovolaemia
2. hx of seizure
3. boxers
4. advanced cardiovasular disease- might not tolerate changes to BP
5. advanced hepatic disease- low metabolism
butyrophenones have similar action to ___ and are used in ___
phenothiazines
used in pigs
actions of benzodiazepine and useful properties
enhance inhibitory action of GABA and glycine in the CNS
1. sedative
2. potentiates CNS and muscle relaxing effects of anaesthetic
3. anticonvulsive
4. muscle relaxant
5., no significant CV effects
6. may stimulate A in cats
7. reversible
disadvantages diazepam
1. unreliable sedation
2, anxiety/aggression in cats?
3. IM injections painful
4. IM and SC absorption unreliable
3 common a2 agonists used in animals
xylazine
medetomidine
dexmedetomidine
differences between xylazine and medetomidine
medetomidine more potent and more a2 specific
action and advantages of a2 agonists
stimulate pre and post synaptic a2 adrenoreceptors in CNS and peripheral tissue
1. profound dose dependant sedation
2. profound analgesia
3. reversible- with atipamezole
undesired effects and disadvantages of a2 agonists
1. bradycardia, 1` or 2` HB
2. reduced CO
3. catecholamine induced dysrhythmias
4. hypertension followed by hypotension
5. poor tissue perfusion
6. respiratory depression at higher dose
7. may cause vomiting (xylazine)
8. xylazine associated with higher mortality rate in dogs
xylazine contraindications
old animal
sick animals
CVD
DOGS- use medetomidine instead
what is the reversal of medetomidine
atipamezole
types of opioids
pure agonist- bind and activate one or more receptor types
partial agonist- bind to one or more receptor type but will activate some but not others
agonist/antagonist- activate one receptor type, inhibit, reverse another
antagonists- bind/block
opiod receptors
mu- sedation, analgesia, resp depression, brady, hypothermia
kappa- analgesia, sedation
sigma- disphoria
pure mu agonists
methadone
morphine
fentanyl
receptor action of butorphanol
kappa agonist
mu antagonist
partial mu agonist
buprenorphine-

can partially reverse pure mu agonist effects or prevent action ofother pure mu agonists that have lesser affinity
useful qualities of opioids
1. analgesia
2. sedation
3. fewer CV effects
4. antitussive
5. reversible
undesirable effects opioids
1. brady
2. emesis, GI hypermotility, initial defecation followed by constipation
3. panting
4. excitation, dysphoria
5. resp depression (high doses)
6. histamine release
7. transient hyperthermia (cats)
contraindications of morphine
in patients in which vomiting may have adverse consequences- stomach tube, eosophagitis, laryngeal weakness
duration of morphone
2-6h
duration of buprenorphine
2-12
duration of butorphanol
0.5-2
pharmokinetic differences in cats compared to dogs
mayu be a different response- buprenorphine may provide better analgesia than morphine
more likely to be adverse effects to morphine
buprenorphine suitable for sublingual administration
undesirable physiological effects of ACP vs Medetomidine
HR: ACP>M
MAP: M>ACP
Cl: ACP>M

cardiac index- CO to body surface
common premedicant combos
tranq+ opioid
- meth/acp
- butorph/ acp
- bup/ acp
-meth/diaz- old ill and debilitated- less reliable sedation

dissociative+ benzodiazepine
- tiletamine/ zolazepam
- ketamine/ diazepam
advantages/ indications of tranq + opioid
improvd sedation at lower dose of tranq
analgesia + sedation
improved recovery
doses can be modified for increased sedation/ analgesia
undesirable effects of tranq + opioid
compounding CV effects
emesis, Gi hypermotikity
panting
useful effects of dissociative + benzo
1. dose dependant sedation + muscle relaxant
2. analgesia
3. rapid onset
4. suitable for young, healthy fractious cats
5. suitable for agro dogs
undesirable effects benzo + dissociative

contraindications?
icnrease salivation
ketamine without benzo= mucle rigidity
recovery may be rough

1. not suitable for dogs unless unmanageable
2. renal cats with renal insufficincy/ failure- requires renal elimination
3, hyperT cats
Preprepared premed combos
BAA
butorphanol, ACP, atropine
MAA
Morphoine, atropine, ACP
BAG
butorphanol, ACP, glycopyrrolate
which premeds have no analgesia
benzos, phenothiaziens
considerations for choice of premed
1. physical status
2. how much analgesia required
3,. how much sedation required
4. what route of drug administration is available
beginnig mask induction
1. o2 only to let animal settle
2. graduallg increase conc of inhalant starting at low setting
advantages of mask induction
No/little metabolism required for regaining of consciousness
• Oxygen enriched gas mixture
• Suitable in severely ill patients
• “Reversible”
disadvantages of mask induction
Relatively slow induction
• Struggling
• Pungent odor = struggling (?)
• Pollution, operator exposure
• Unsuitable for most patients
• Anaesthesia machine required
advantages and disadvantages of chamber induction
Advantages/indications

No patient restraint required
• Suitable for intractable small patients

Disadvantages/contraindications
Rough induction
• Pollution difficult to avoid
• Contraindicated in any manageable patient
characteristics of injectible induction anaesthetic- adv/ disadv
•Rapid loss of consciousness
• Muscle relaxation
• Short duration of action
• Minimal CV depression

diadv
venous access required
doe calc and adjustment required
how to manage cardiopulm effects of IV anaesthetics
Cardiopulmonary effects are
dose dependent
Dose can be minimised by:
1. Adequate pre- medication
2. Slow injection
how to choose a safe IV anaesthetic
a. mortality rate (thio lowest)
b, adverse effects
c. therapeutic index
d. recovery
e. contraindication
effects of induction anaesthetics on MAP in unpremedicated dogs
MAP idecreased with propofol, alfaxolone

increased with thio and ketamine
effects of thiopental
HR +
MAP 0 or +
CO 0 or +
dysrhythmia ++
oxygenation -
pulm ventilation --
effects of propofol
HR +
MAP 0 or -
CO 0 or +
dysrhythmia +
oxygenation --
pulm ventilation --
effects of ketamine
HR ++
MAP 0 or +
CO 0 or +
dysrhythmia +
oxygenation 0 or -
pulm ventilation -
rough recovery
seizures
effects of alfaxan
HR +
MAP 0 or - (dose dependant)
CO 0 or +
dysrhythmia ?
oxygenation --
pulm ventilation --
relative therapeutic index of induction anaesthetics
thio (7)<propofol (8)< < ketamine (13) << alfax (30)
time and quality of recovery, IV anaesthetics
propofol best wuality- 10 mins action, 20 mins walking
alfax, 10, 20
ketamine 15, 20
thio 12, 80
half life of injectable anasthetics
Alfaxolone 25 min
Propofol 30-60 min
Ketamine 2-3 hrs
Thiopental 8 hrs
What does half life tell us

Half life determines “slope” of
metabolic curve

Half life determines time to
complete recovery (not to time
of regaining consciousness)

Half life determines amount of
drug left in body at time of
regaining consciousness
main properties of induction anaesthesias

Half life determines “slope” of
metabolic curve

Half life determines time to
complete recovery (not to time
of regaining consciousness)

Half life determines amount of
drug left in body at time of
regaining consciousness
contraindications thio
Severe liver disease/dysfunction
• Pre-existing cardiac arrhythmias
• ASA >3
• Advanced cardiac disease (poor contractility)
• Cesarean section
• Greyhound dogs
• Emaciated patients
propofol contraindications
• Hypovolaemia
•Advanced cardiac disease (poor contractility)
• Bradycardia (sick sinus syndrome)
• Consecutive days in cats
• Disease condition where hypotension poorly tolerated

NEEDS PROPER STORAGE
contraindications of ketamine
Increased intraocular pressure*
• Increased intracranial pressure*
• (Seizures)
• Cats with renal disease/urinary obstruction
• Caesarean section
• Heart disease (increased contractility, myocardial
failure)
*Mostly significant if Ketamine used without benzodiazepines
maximising safety of IV anaesthetic induction
no ketamine or thio for PS 3 or 4

1. Calculate dose!
2. IV catheter
3. Administer as directed!
4. Always check patient before
induction (HR, PR, MM colour)!
5. Administer oxygen via mask for 5
min before induction
adv and disadv IM induction
Advantages;

No venous access required
• Suitable for “difficult” animals
• Suitable for very small animals
Disadvantages/caution:

Relatively slow onset
• Effect less predictable
difficult to titrate to effect
• Over -, under-dosing possible
• Prolonged recovery
advantages of iv induction
able to titrate to effect

Immediate onset of action

Peak effects rapid

Short duration of action as relatively low dose required
for desired effects
advantages of endotracheal intubation
decreases workload of breathing
provides secure and patent airway
minimises pollution during inhalation anaesthetic
minimal equipment dead space compared to mask- reduced anatomical dead space
artificial ventilation possible
airway protection- less likely to aspirate
When to extubate
dogs- swallowing reflex
cats- light plane of anaesthesia- leaving in too long can cause laryngospasm
Managing anaesthetic waste gases
- use scavenger system
- check machines for leaks- close relief valve, bock breathing tube, press gas valve, check pressure guage
- used cuffed ET tube
- dont turn vaporiser on until ET cuff inflated
- turn o2 and vaporiser off and empty rebreathing bag before disconnecting patietn
- careful filling vapourisers
o2 flow/ vaporiser settings for breathing and non rebreathing
rebreathing-
first 5-10 mins 1-2L/min (2-3%)
second 5 min 30ml/kg/min (2-2.5)
continue: 30ml/kg/ min (1.5-2%)
WHen discontinuing- turn off vaporiser and turn o2 back up to 1-2l/min

non-rebreathing
300ml/kg/min
first 5 (1.25-1.5)
second 5 (1-1.25%)
continue (0.75-1.25)
how is potency of inhalational anaesthetics measured
Minimum alveolar concentration- concentration requird to maintain 50% patients non-responsive to a painful stimulus
halothane<iso<sevo
how are inhalational anaesthetics absorbed?
vapour are delivered to the blood stream, via the respiratory tract. From the alveolar space, they are taken up in the blood and then tissues in which they will dissolve depending on their solubility
haemodynamic effects of the three main inhalational anaesthetics
- simialr dose related decrease in MAP seen with all 3
- CI least affected by isofluorance- similat at lower doses with sevofluorane, but decreased at higher doses. Most affected by halothane
respiratory depression caused by the three main inhalational anaesthetics
isofluorane causes more respiratory depression in dogs and horses than the other two, less so in cats
halothane causes greater respiratory depression in cats
reasons for iso and sevo use over halothane
maintain tissue bloodflow better at low doses- less hepatotoxicity, nephrotoxicity
low arrhythmogenicity
cardiac output better maintained by iso
Factors affecting speed of onset of action of inhalant anaesthetics
1. anaethetist factors- vaporiser setting, o2 flow (rebreathing), choice/ volume of breathing circuit- only influence arterial partial pressure
2. Solubility of anaesthetic
3. patient factors- tidal volume, RR, CO, tissue bloodflow

= S x CO (partial arterial pressurex partial venous pressure i.e blood flow)
factors affecting speed/ quality of recovery
1. premedication- increases recovery time but significantly improves quality of recovery
2. induction agent used- shorter halflife with have faster metabolism and redistribution- result in more complete recovery, less hangover effect
3. if prolonged anaethesia- higher fat solubility of inhaled anaesthesia could prolong recovery
factors affecting choice of anaesthetic
1. safety
- CO depression (halo>iso)
- arrythmogenicity(halo>iso)
- metabolism (halo>iso)
2. onset of ation/ speed of recovery- similar
3. cost
causes of anaesthesia related mortality
- cardiovascular complications (30-70%)
- respiratory complications (30-50%)
- unknown (5-25%)
>3/4 due to human error- inappropriate anaesthetic depth
Usual cause of death in anaesthetised patient
tissue hypoxia caused by hypoventilation, circulatory dysfunction and poor oxygenation

= Inappropriate anaesthetic depth, inadequate patient monitoring
Assessing anaesthetic depth
balance between effect of anaesthetic drugs and magnitude of painful stimulus- subjective measure
1. physical signs
2. cardiopulmonary responses to painful stimuli
Indicators of anaesthetic depth
Reliable- spontaneous movemet (light)
refelx movement
cardiopulmonary response- light to med

less reliable
muscle/jaw tone
palpebral reflex
eyeball position
PLR- absent deep +/- med
Principles of patient monitoring
1. regularly assess depth
2. Circulation
3. oxygenation
4. ventilation
- anaesthetic record
- personnel
monitoring circulation in the anaesthetised animal
1. HR manual- HR, PR- early problem detection difficult
electronic- oesophageal stethoscope
2. BP- SAP (force), DAP (filling), MAP (perfusion pressure)
doppler or oscillometric
3. BP- palpate lingual, femoral, dorsal pedal artery for pulse quality
importance of monioring BP
most easily measured indicator of adequacy of circulation
- fucntion of CO and systemic vascular resistance
blood pressure + mm gives indication of blood flow
interpretation of pale mm in anaesthetised patient
pale with high BP- vasocontriction due to light plain of anaesthesia, hypothermia
pale with low BP- vasoconstriction and poor CO- blood loss, hypothermia
how does doppler BP monitor work
1. occlusion of blood flow in appendage by pressurising cuff (ciff width 30-40% apendage circumference
2. returning flow once SBP is equivalent to cuff pressure as cuff deflated slowly by sphygmomanometer'
return of sound= SAP
3. flow detector placed over artery- distal to duff
how does oscillometric BP analyser work
1. cuff inflated to supra systolic P
2. cuff slowly deflated- oscillation amplitudes measued and averaged at each step
SAP- pressure when ampliture rapidly increases
DAP- rapid decrease
MAP- lowest prssure with greatest av oscillation
oscillometric BO analyser- application sites
1. forelimb- prox to carpus
2. hindlimb just above/below hock (better)
3. tail base
positon cuff at heart level
disadvages oscillometric
under reads SAP
over or under estimates MAP and DAP- not as much as SAP- less if on hindlimb
Doppler measurements in dog
normal, conscious- 152
anaesthetised- 120
hypotension- 85
severe hypotension <75
hypertension >180
Doppler measurements cat
normal, awake 136
anaesthetised- 94
hypotensive 70
severe hypotension <60
hypertension >190
tissue oxen delivery algorythm
cardiac output + blood oxygen content (mostly PO2xSaO2xPCV)
Relationship between PO2 and SO2
oxygen- haemoglobin dissociated curve
at low PO2, small change to PO2 causes drastic change in SO2- never want animal under 85-90SO2
Anaemic animals- SO2 will be normal even if PO2 low
measuring oxygenation
1. BGA
2. haemoxymetry
3. pulse oxymetry
advantages of pulse oxymetry
clinical practical and useful for assessing ocygenaton
pulse monitor- will alarm if no detectable pulse
non invasive
continuous
simple to apply
allow for early detection of problems
disadvantages pulseoxymeter
accuracy affected by:
- poor perfusion
- vasoconstriction
- hypoterhmia
- anaemia
- changes in background absorption
Main principles of monitoring ventilation
adequate pulmonary ventilation is dependent on RRxTV
Alveolar ventilation is the amount of air per time unit that reaches the alveoli and takes place in gas exchange- most important way that body can excrete CO2
THerefore CO2 elimination can be used as a way to assess alveolar ventilation
1. Arterial CO2 (PaCO2) is inversely proportional to alveolar ventilation
2. alveolar CO2 and arterial CO2 are close to equal
3. PCO2 in the end tidal air (ETCO2) can be used as a measure of PaCO2
measuring pulmonary ventilation
1. rate, depth of breathing- observe rebreathing bag
2. PaCO2- BGA- invasive
3. Capnometry- ETCO2
normal ETCO2
35-45

elevated plateau
>45 indicated hypoventilation
>55 requires intervention

low plateau
<35 hyperventilation- light plane
small patient with small tidal vol/ hypotension
sudden decrease in ETCO2
1. Apnoea
2. inadequate pulm blood flow- severe hypotension, cardiac arrest, air embolism
3. side stream sampling system occluded
ddx elevated baseline ETCO2
exhausted soda lime
defunct one way valve - rebreathing
inadequate gas flow- rebreathing
6 most common anaesthesia complications
1. hypothermia
2. hypoventilation
3. bradycardia
4. hypoxaemia
5. hypotension
6. inappropriate depth
recognising hypotension
1. poor pulse quality
2. poor BP
3. pale MM
4. Pulseox failing to read
tx perianaesthetic hypotension
1. asess patient/depth
2. adjust vapouriser
3. analgesia
4. IV bolus
5. sympathomimetics- dopamine, ephedrine
recognising hypoventilation
1. reduced RR <4
2. poor tidal vol
3. difficulties maintaining anaesthesia
4. elecated ETCO2
treatment hypoventilation
1. assess depth
INDUCTION APNEA
if light- give 1 poitve pressure breath every 30s
if deep- turn off vapourer, empty bag, fill with 02, breath until spontaneous breathing returns
HYPOVENTILATION
1. assess depth
2. check positioning
3. reduce by 1/3
4. artificail breath
causes of bradycardia
inappropriate depth
pain
anaesthetic drugs, opioids, a2 agonists
hypothermia
tx bradycardia during anaesthetic
1. check patient
2. check pulse
3. additional analgesia if due to pain
4. atropine 0.02mg/kg repeated 2-3 times in 30-60 sec intervals then .02mg s/c once effective
treatment of tachycardia during surg
check patient
analgesia
mm colour, pulse ox, ETCO2- ensure ventilation, o2 delivery
adjust vaporiser
recognition of perianaesthetic hypoxaemia
cyanotic mm
tachy
increased pulm ventilation
treatment anaesthetic hypoxaemia
1IMprove pulm blood flow
- decrease anaesthetic depth to improve CO
- fluid bolus
- sympathomimetics to improve tissue delivery
2. improve alveolar ventilation in order to improve o2 uptake
- decr vaporiser
- PPV- but may decr CO
actions of opioids
1 activation of descending inhibitory pain pathways
2 inhibit pain transmission in the dorsal horn
3. inhibit excitation of peripheral sensory nerve endings
4. inhibit relesse of substance p and other neuropeptides at the dorsal horn gsnglia and sensory nerve endings
side effects of opioids
dose dependant...
respiratory depression
brsdycardia
morphine in higher doses can cause histamine release-hypotensiom, hupovolaemic shock
morphine, apomorphine vomiting defectaiom then constipation
high doses cats csn csuse cns excitement
sedation
cns tolerance
which opioid mostly used for epidural and why
morphine. less lipophilic. slower diffusion into meninges, longer duration of action
nsaid analgesia vs opioid analgesia
1 analgesia w,o sedation
good for inflammatory pain
less effective analgesia than opioids
generally poor visceral analgesia- except in horse w flunixin
benefits and disadvantsges of using a2 agomists for pain management
effective analgesia
potentiate opioid analgesia- synergistic
sedation

profound sedation
cardio effects- hypertension then hypotension, bradycsrdia, decreased CO
useof a2 agonists for analgesia
reserved for young healthy animals, used most commonky as part of sedation protocol for short minor procedures in clmbimation with opioid (eg medetomidine and torbugesic)

contraindicated in old ill pstients
csrdiac patients

low doses in adjunct anaesthesia
lethal La doses
bupivicaine 3mg.kg
lignocaine 10mg.kg (4mg.kg cat)
hoe dose LA toxicity occur
resuly of inhibitory effects on excitable cells other thsn peripheral cells. eg brain and myocardium
cns tox occurs at lower plasma conc than myocardial tox
first cns depressiom, then as inhibitort pathways affected, cns excitemrnt, then coma
clinical signs of la tox
sedation
restlessness
confusiom progressing to excitation, nystsgmus, opsthotonus, muscle tremor, seizures, followed by cns depression and coma

Cv tox- affects myocardium and vascular sm
decreased contractility
decreased conduction
decreased excitability
properties affectimg action of an la
1. lipid solubility- more soluble, less needed
2. protein binding- increased duration of actiom
3. dissociative constant- availavility of nonionised active form and trapping of ionised LA within excitable cell
action and uses of tramadol
centrally acting synthetic anslogue of codeine
parent compound and M1 metabolite act at mu opioid receptors amd serotonin and adrenergic receptors.
analgesic potency 1/10th that of morphine

used mostly for chromnic psin or pain late in postop period
csreful in cats
tranqs for analgesia
potentiate opioid analgesia but (exc for medetomidine) provide no analgesia on their own
eg AcP meth, diaz mrth, midaz meth
cornea LA
proparacine, proxymetacaine 0.5%
innervation around the horses eye
supraorbital n
lacrimal n
infratrochlear n
zygomatic n
desensitising horse eye
suprsorbital medial 2/3rds
medial (infratrochlear) amd lsteral (lacrimal) canthus- infiltrate respective eyelid
cornea- proxtmetacsine or proparacine
lower eyelid (zygomatic)- lowest point of orbit
globe- 2-3cm lateral to laterL csnthis then ventromedial
desentising goat horn
cornual branch 1. cornusl br of zygomaticotemporal n- midway between lateral canthus of eye and lateral margin of horn
cb2. cornusl br of infratrochlear n
nerves from the brachial plexus
axillary, rwdial, median, ulnar, musculocutaneous
procedures performed under epidural and sedatiom in lsrge animals and where?
procedures involving tail, perineum, anus, rectum, vulva vag, prepuce, bladder, skin scrotum

sacrococcygeal junction or between first 2 caudal vertebrae (caudal epidural)
differemce between csudal and lumbosacral epidural
LS will result in motor ans sensory loss in pelvic limb and depending on dose, the abdo wall

Sacrococcygesl, if recommended dose used, wont affect motor and sensory innervation to limb so pstient csn remain standing
duration of effect of epidural ligno vs bupiv
ligno 1 to 4
bupiv 3 to 6
what opioid is commonly used for epidural analgesia and why ?
Morphine
low lipid solubility = slow onset but long duration
side effects of epidural opioids
Potential urinary retention
potential pruritis
Sedation
what effect does epidural a2 agonists have agonists have ?
Selectively mediate pain
Regional anaesthesia → Xylazine + detomidine (horse only)
Xylazine has some additional LA effects
Systemic side effects (Brady cardio, hypotension, sedation) → only det in horses, xyla in cattle
lignocain + xylazine in horse → anaesthesia + some analgesia of rapid Onset and lasting longer than each on its own
Onset of action & duration epidural ligneous bupiv
ligno fast 10-15
bupiv 20-30

ligno l-2hr
bupiv 4-6hr
Duration of epidural Morphine
depends on severit y of pain, site of pain, extensiveness ) pain tolerance
generally 24-48 hours
Technique for dog epidural
sterna l or lateral
clip (scrub
thumb / middle finger on highest points of iliac crest,
Index finger just Caudal to spinal process of L7 on midline
Insert needle 90° just in front of finger
feel 9'pop'as needle passes through ligamentum flavumand enters spinal cord
remove stylus → if CSF (subarachnoid puncture ) decrease dose b y 30'I.
inject 1MI air or saline w/o resistance
inject slowly over 10-15 seconds

dont exceed 6mL
3 Commandments of epidural
l. be clean
-scrub (clip
-new vials including diluent
2. be meticulous
~ always Calculate correct dose
dont exceed 6mi
always aspirate first