Pre-med Flashcards
what are the 3 components of an ideal anesthetic technique
analgesia, stability of organs/systems and loss of consciousness
what is general anesthesia
reversible process of depression of the CNS with drugs that produce unconsciousness
what is a balanced technique
administration of different drugs together to create the ideal anesthetic state
what is the objective of an ideal balanced technique
uses less of each drug than if the drug were administered alone, thereby increasing the likelihood of desired effects and reducing the likelihood of its side effects
what do we want to achieve with pre-medication (3)
sedation, anxyolisis, muscle relaxant
why do we premed patients (9)
-Decrease stress and facilitate patient handling
-Staff safety (especially important in aggressive patients and wildlife)
-Facilitate restrain and catheter placement
-Provide preventive analgesia prior to surgery
-Facilitate monitoring and pre-oxygenation before induction
-Decrease doses of induction agents
-Smoother anesthetic inductions
-Lower inhalant requirements
-Better recoveries for short procedures
what are some advantages of giving preventative analgesia prior to surgery
-Reduction of noxious stimuli reaching the central nervous system during surgery
-Reduction of peripheral inflammation
-Reducing the dose of anesthetic required during surgery
-Less analgesia needed post-op
-More rapid hospital discharge
what is the purpose of giving preventative analgesia prior to surgery
attempt to block nociceptive input through the application of several analgesic agents, acting at different sites (multimodal analgesia) starting prior to surgery and continuing for several hours or days following surgery
dose dependent combiniation of propofol and alfaxalone
dose dependent hypotension and respiratory depression
dose dependent issue with inhalants
dose dependent vasodilation and hypotension
what are some disadvantages of pre-meding patients? (4)
-possibly cost; depending on drug used since you decrease the amount of induction and maintenance drugs
-time; onset of action is slower when IM or SQ routes are used
-some sedatives arent appropriate for sick patients (There is no safe or perfect premedication protocol acceptable for ALL ANIMALS, All drugs cause side effects that are usually dose-dependent)
-Heavy sedation protocols carry higher risk of cardiovascular side effects, respiratory depression or airway obstruction
what type of drug do we use to achieve sedation/anxyolisis
anesthetic agent
what type of drug do we use to achieve muscle relaxation
sedative agent
what type of drug do we use to achieve analgesia
opioid
what are some features of an ideal pre-anesthetic protocol (5)
-Provide reliable and consistent sedation, anxiolysis and/or immobilization
-None or minimal side effects
* Cardiorespiratory
* Other systems
-Provide adequate analgesia
-Reversible
-Reduce the dose of other sedative, anesthetics
what is a common drug in the phenothiazine class
acepromazine
what are common drugs in the alpha-2 agonist class (2)
medetomidine and dexmedetomidine
what is a common drug in the benzodiazepine class (2)
diazepam and midazolam
what is a common drug in the opioid class
pure agonists= morphine, hydromorphone, methadone, meperidine, fentanyl)
partial agonists= buprenorphine
kappa agonists = butorphanol
what is a common drug in the anesthetics class
-ketamine IM
-alfaxone IM
-subanesthetic doses propofol or alfaxalone IV
what is a common drug in the oral sedatives class
trazadone and gabapentin
what is a common drug in the anticholinergics class
atropine and glycopyrrolate
what are the three categories of opioids
pure agonist
partial agonist
kappa agonist
what is the goal of neuroleptic combinations?
Achieving the desire degree of sedation, anxiolysis, immobilization and analgesia while decreasing
doses and therefore side effects of every drug chosen
features of neuroleptic combinations (3)
- Combination of drugs with synergistic actions
- Lower doses of all agents = less side effects
- More realizable sedation or analgesia, quicker onset, longer duration…
what are 8 general considerations you need to think about when choosing a protocol
-ASA status of your patient and specific pathophysiology of diseases present
-what degree of sedation do i need
-what degree of analgesia do i need
-onset and length of effects needed; dose and route of administration
-drugs and doses must be tailored to the specific patient (pre-mixtures not recommended)
-knowing drug pharmacology and expected side effects for every drug is crucial
-always monitor patients closely after pre-med specifically if heavy sedation is needed
-mild sedation is usually safer, heavier sedation may result in more side effects
what do you need to think about regarding ASA status when choosing a protocol
- ASA (I-V) used to determine anesthetic risk
- Age (Neonate, Pediatric, Adult, Geriatric)
- Patient condition and health status (Hepatic disease, Renal disease, Cardiac disease)
what determines the degree of sedation used in your protocol
- Procedure to be performed
- Personality of the animal
- Resources available in clinic/setting
what type of opioid class should you use for diagnostics and non-invasive things
partial -agonists/antagonists like butorphenol or buprenorphine
what type of opioid class should you use for minor procedures
partial u-agonists/ u-pure agonists
what type of opioid class should you use for surgery or an already painful condition
u-pure agonist
advantages and disadvantages of using opioid alone
- Advantages: minimal cardiorespiratory depression, more sedation in sick patients
- Disadvantages: Only mild sedation in healthy patients
what class of sedatives would you use if you wanted a mild sedation
opioids, benzodiazepines, low dose acepromazine
what class of sedatives would you use if you wanted a moderate sedation
Acepromazine, low dose α2-agonists or Alfaxalone
what class of sedatives would you use if you wanted a profound sedation
α2-agonists, ketamine, Alfaxalone combinations
can you use a sedative alone
its not recommended
what is one of the most important things to think about when giving a sedative to a patient
ask yourself if any of the agents are contraindicated in that specific patient and case
sedation scoring 1-4
1 = no effect
2 = mild sedation; quiet but still active and alert
3 = quiet, reluctant to move, slightly ataxic but able to walk
4 = animal recumbant, unable to walk
