Dr. Matthews Lecture

Card Set Information

Dr. Matthews Lecture
2014-04-19 23:00:49
vet tech 247
vet tech 247
new analgesic drugs and newer uses of drugs in surgical nursing, anesthetic management of challenging cases, emerging issues and other problems vetc 247
Show Answers:

  1. recuvyra
    • transdermal fentanyl, spot on like flea/tick.  
    • control of postop pain in DOGS for 4 days with 1 application
    • FDA approved.  Reversible
    • apply 2-4h before surgery, hold 2 mins to dry
    • complete safety information, training required
  2. Buprenorphine SR
    • partial mu opioid agonist, injectable
    • not FDA approved
    • 72 hour duration
    • cats only
  3. cimicoxib
    • coxib NSAID, not in US (UK and Europe)
    • chewable tab
    • SID, 2h prior to surgery, 3-7 days post-op
  4. alfaxalone/alfaxan
    • synthetic neuroactive steriod that acts on gaba receptors, like propofol (but clear)
    • already used in australia and canada, approved in US 2012 (DEA schedule IV)
    • slow IV, apnea, twitching/paddling, CRI, okay for pups <12 weeks. 
    • Good for cardio with hypovolemia, less cardiac depression (hypotension) than propofol
  5. methadone
    • opioid becoming popular
    • mu-receptor agonist and NMDA-receptor inhibitor
    • less vomiting and dysphoria than other opioids
    • no hepatic glucuronidation, good for cats
    • better painkiller than torb or bupe
  6. pregabalin
    • anticonvulsant (metabolite of gabapentin), tx of neuropathic and chronic pain in dogs and cats
    • better bioavailability, lower dose, fewer side effects
    • expensive
  7. desflurane
    • newest of inhalants
    • High vapor pressure, heated vaporizer (hard to transport)
    • low solubility (rapid uptake, rapid elimination)
    • Start high on vaporizer
    • great for horses
    • more coughing than with sevo
  8. sevoflurane vs desflurane
    • more coughing with desflurane
    • no significant difference in time to recovery or discharge
  9. lidocaine patch
    • old drug, new preparation.  Approved for humans.  Can be cut.  
    • goats and cats have lidocaine toxicity problems
    • safe in dogs
  10. Anipryl/selegiline
    • behavior modifier for senile old dogs
    • MAO inhibitor, enhanced catecholaminergic activity
    • don't use with demerol, alpha-2 agonists (cardio), Tri-cyclic antidepressants, SSRI's
  11. Clomicalm (Clomipramine HCl)
    • behavioral modification (anxiety)
    • interacts with anticholinergics, sympathomimetics, CNS-active drugs, general anesthetics
  12. tri-cyclic antidepressants
    • decrease uptake of neurotransmitters after initial INCREASE (this window is especially dangerous) for 2 weeks
    • long half-life, highly protein bound, require hepatic metabolism, renal excretion, affected by age and acid-base, may affect clearance of other drugs
  13. List of tricyclic antidepressants
    • amitriptyline
    • desipramine, doxepine
    • nortriptyline
    • used for behavior modification
  14. side effects of tricyclic antidepressants
    • tachycardia
    • hypotension
    • hypertension
    • serious dysrrhythmias
    • CNS effects: sedation to seizures
  15. fluoxetine (Reconcile)
    • selective serotonin reuptake inhibitor (SSRI)
    • used for separation anxiety
    • not for use with MAOI's, TCA's
    • seizures, weight loss
  16. mirtazepine (Remuron)
    • tetracyclic antidepressant
    • no veterinary label
    • sued as appetite stimulant, side effects include nausea and vomiting
    • Not used with clonidine, MAOIs, SSRIs, TCAs, Celebrex, Tagamet, Cipro, ketoconazole
    • kidney or liver disease
    • Hypo, hypertension, tachycardia
  17. Drugs that interact with anesthetics
    • phenylpropanolamine (PPA--proin, etc)
    • phenoxybenzamine
    • both produce cardiac arrhythmias
    • propantheline (tachycardia, hypertension with anesthetics)
  18. exotic breed anesthesia
    minimal drugs with maximal monitoring
  19. P-glycoprotein expression
    • multidrug resistance gene
    • P-glycoprotein limits drug entry into CNS
    • Deficient in collies and Australian shepherds (ivermectin sensitivity)
  20. greyhound anesthesia
    • racing vs retired - how fit the animal is
    • propofol best for induction, acepromazine best as premed
    • hyperthermia may be from excitement (shivering)
    • blood values are different - high hematocrit
  21. general approach to challenging patients
    • thorough physical exam
    • how/why is this patient different, physiologically, and how will that affect drugs chosen
    • what problems are likely to occur
    • how can you prevent or manage problems
  22. emergency preparedness
    • emergency drug dose sheets
    • emergency drugs and equipment in location separate from all drugs
    • check drug dating
    • run fire drills
  23. preoperative lab work
    • no firm guidelines on standard of care
    • depends on practise, client, relationship, breed/species
    • establish a baseline
  24. preoperative fasting guidelines
    • 6-8 or 8-12h food, 2-4h or no withdrawing of water.  
    • for humans calorie loaded clear fluids recommended up to 2 hours before
  25. clinical problem with F-circuits
    • rebreathing when inside tube disconnects
    • designed for single-use
  26. the trouble with cats
    • difficult to restrain
    • behavior (O may not know)
    • difficult to intubate
    • small size = rapid changes
    • monitoring equipment often fails (too small)
    • more underlying disease than we know
  27. premeds for cats
    • acepromazine
    • midazolam
    • butorphanol (can be combined with ace or midaz)
    • ketamine (low dose as sedation, high dose as anesthetic)
    • buprenorphine
  28. propofol in cats
    • no approved for cats (though it works)
    • slow IV (titrate)
    • NOT with a ketamine premed
  29. common complications in cats
    • "wound up" cat - sudden arrest from too many catecholamines
    • tracheal trauma - too light at intubation or position changes
    • bronchoconstriction at extubation (albuterol inhalation)
    • difficult to keep asleep and monitor
    • easier to intubate bronchus (short neck)
  30. ketamine
    • NMDA receptor (N-methyl-D-Asparatate) antagonist
    • prevents wind-up and sensitization
    • supports blood pressure and heart rate while maintaining anesthesia
  31. geriatrics
    • underlying renal or cardiac disease
    • have "blunted" responses to reflexes (no baroreceptor, etc)
    • less muscle, higher body water
    • adverse response to hospital environment
  32. opioid analgesics as a pre-anesthetic
    • may provide sedation
    • provide pre-emptive analgesia
    • respiratory depression
    • bradycardia
    • minimal cardiovascular depression
    • good for geriatric
    • reversible
  33. hydromorphone
    • almost identical to oxymorphone, but less expensive
    • may produce more vomiting
  34. buprenorphine vs butorphanol
    • both good for geriatrics
    • torb shorter duration
    • bup lasts longer
    • fairly inexpensive
    • no vet approval in US
  35. induction for geriatrics
    • propofol
    • etomidate - little cardiovascular depression. Good for old, sick, high-risk (rough on healthy)
    • ketamine/diazepam or telazol (maintain BP and HR)
    • mask induction (only 1 drug on board, but must get too deep to intubate)
  36. sevoflurane
    • low solubility = 0.65
    • MAC = 2.3%
    • metabolism < 5%
    • approved for dogs, often used in cats
    • good mask inductions (not smelly)
    • less bronchial spasms than iso (asthmatics?)
  37. indications for sevoflurane
    • high-risk patients - where good control is important
    • fewer arrhythmias (like iso)
    • cesarian sections (puppies get rid of it fastest)
    • outpatient procedures - early discharge
    • good for problem cases
  38. problems for maintenance for geriatrics
    • hypotension - use of IV catheter and fluids is essential
    • restore fluid balance before anesthesia
    • inhalants allow rapid depth change and recovery, produce hypotension in dose-dependant, minimize drugs requiring metabolism
  39. uses of local anesthetics
    • good to minimize inhalants
    • epidurals, local infiltration, anatomic nerve blocks, "splash blocks", dental blocks
    • lidocaine (short term), bupivicaine (long duration)
  40. lidocaine
    • local anesthetic
    • CRI will reduce MAC for inhalants 30-50%
    • not recommended for cats due to cardiovascular depression
  41. bupivicaine
    marcaine, lasts 8-12 hours but takes 20-30 mins to produce block
  42. fentanyl CRI
    • short-acting opioid
    • stop before extubation
    • will allow vaporizers to be marked down markedly
    • minimal cardivascular depression
  43. pediatric patient concerns
    • heart-rate dependant (no complementary vaso, can't fix CO)
    • immature liver and kidneys
    • less body fat, higher water concentration
    • fast metabolic rate
    • easy to intubate bronchus
    • small size
    • care with fluid administration
    • plain saline to avoid too much heparin
    • WEIGHT of drape may impede ventilation
    • difficult to monitor (too small)
  44. things to do for pediatrics
    • use anticholinergics (premed with glyco and torb, induce with propofol, ket/val, telazol, maks, maintain with inhalant)
    • not before 4-6 weeks
    • shorter acting drugs preferred
    • keep warm
    • check blood glucose
    • tendency towards lower blood pressure
    • monitor temp, glucose, BP, HR, RR, CO2
  45. pregnant/cesarian section concerns
    • elective vs sick
    • who is priority?
    • ALL DRUGS CROSS PLACENTA, a matter of concentration and time.
  46. Cross the placenta
    • ALL DRUGS CROSS PLACENTA, just an issue to time/concentration
    • anesthetic drugs cross fast, lipid-soluble for blood-brain means can go across placenta
    • glyco crosses VERY slowly
    • epidural doesn't keep them from moving
    • Can't prevent pups from getting drugs, use one they can get rid of fast like propofol/sevo or reversible
    • Maintenance of BP VITAL to ensure blood flow to uterus (preload fluids)
    • NSAIDs hard on puppy kidneys
  47. bracycephalics
    • airway nightmare
    • prevent panting/agitation: avoid mu, use ace
    • use drugs which produce rapid, smooth recovery
    • airway swells, steroids or lasix?
    • extubate late
    • prep for tracheostomy
    • monitor temp
  48. angry mean dogs
    • telazol, torb
    • get meds into dog, don't care where
    • pre-med with hydromorphone and ace
    • induct with propofol, more telazol or mask
    • No alpha-2 agonists (can't trust)
    • watch high catecholamines (collapse, arrhythmias)
  49. telazol
    • tiletamine-zolazepam
    • IM, SQ, IV
    • recovery time is dose-dependant
    • approved for IM in dogs and cats
  50. common problems to anticipate, prepare for and stay ahead of
    • hypoglycemia
    • hypotension (hypovolemia, hypoproteinemia)
    • hypothermia
    • pain
    • cardiac arrhythmias
  51. anticholinergics as a premed
    • not if high heart rate
    • handling GI will produce vagal response
  52. opioids as premed
    • beware of producing vomiting
    • IV administration just prior to induction or can give after induction
    • choice of opioid may affect vomiting
  53. induction drug protocol
    • pre-oxygenation is important
    • titrate dose
    • mask may be okay if no vomiting
    • induce while attached to monitors
  54. propofol vs etomidate
    • etomidate causes transient immune suppression
    • decision based on cardiac function
    • could also use ketamine/diazepam
  55. drugs for epidurals
    • local anesthetic: lidocaine, bupivicaine
    • opioid: morphine, oxymorphone
    • combination of both
    • intra- and post-operative analgesia
  56. intra-operative management
    • titrate inhalant needs, may be minimal as sickness decreases MAC
    • multiple catheters may be needed
    • support aggresively: fluids, inotropes, colloids
  57. blood gas analysis
    • useful for eval of acid-base (venous sample okay)
    • electrolytes
    • lingual vein is good for sampling
  58. MAC requirements decreased by
    • age
    • hypothermia
    • concurrent drug administration
    • disease
    • when it doubt, turn it down
  59. intraoperative analgesics
    • lidocaine CRI - decrease vaporizer to offset hypotension
    • fentanyl CRI
    • ketamine CRI
    • opioids by bolus
  60. emergency preparedness
    • emergency drugs available
    • dosing chart available
    • drug sheet preprinted per patient
  61. inotropic drugs
    • dobutamine
    • dopamine
    • ephedrine
    • vasopressin
    • epi/norepinephrine
  62. colloids
    • hetastarch
    • newer colloids (pentastarch)
    • hypertonic saline
    • combination of hetastarch and hypertonic saline
  63. hypothermia
    • decreases need for inhalants
    • prolongs recovery
    • slows heartrate
    • can cause cardiac collapse
    • open abdomen can cause
  64. renal disease considerations
    • maintain blood pressure (MAP > 65-70 mmHg)
    • IV fluids recommended
  65. cardiac disease considerations
    • cardiac-sparing drugs (like opioids)
    • caution with fluid administration
  66. the key to success with difficult cases
    • monitoring
    • HR, respiratory rate, depth of respiration, BP, SpO2, capnography, ECG, blood gas