Anesthesia Medications Flashcards
Goals for anesthetic therapy should be to reduce likelihood of complications, such as ________.
Long term pain
Pre-anesthesia meds should decrease _____ without producing excessive ______, provide ______ for the perioperative period, and relieve preoperative ____.
Anxiety; drowsiness; amnesia; pain
T/F One of the goals of anesthesia is to reduce the volume and acidity of gastric contents
True
Examples of pre-anesthetic medications include ____, ____, and others, such as ____, ____, and ____.
Benzodiazepines
Barbiturates
Others (antihistamine, phenothiazine, butyrophenes)
Intravenous anesthetics include medications such as ____, ____, ____, ____, and ____.
Propofol, Barbiturates, Etomidate, Opioids, and Ketamine
pneumonic: P[lease], BE OK
Benzodiazepines raise the threshold for ____ ____ of local anesthetics
CNS toxicity
What are the effects of taking a BZD?
Reduce anxiety and have “calming” effects
BZDs have a (gradual/rapid) onset and a (long/short) duration of action
BZDs have a rapid onset and short duration of action
What are three examples of BZDs that can be used pre-operatively? Which of the three has the most limited use? Why?
Diazepam, Lorazepam, and Midazolam
Diazepam is limited due to its lipophilicity
Which of the the three examples of BZDs that can be used pre-operatively is the most frequently used? Why?
Lorazepam is frequently used due to multiple administration routes, and it is hepatically metabolized and eliminated “cleanly”. It is thus usable in the more limited/older populations.
Midazolam causes retrograde amnesia and is therefore useful in what type of procedures and what type of population?
Colonoscopy
Children
What are two adverse effects of BZDs?
Sedation
Disorientation
Barbiturates may provide ____ and reduce ______ prior to surgery. They may also yield _____ if pain is present.
sedation; apprehension; disorientation
Tolerance to barbiturate is observed in patients w/ what SHx?
Chronic alcohol use
Barbiturates have an onset of ____ and a duration of ____.
Onset: <1 minute
Duration: 5-10 minutes
What are two examples of barbiturates that are used pre-operatively/intravenously for anesthesia?
Pentobarbital
Thiopental
What are two possible adverse effects of barbiturates?
Cardiac and respiratory depression
The use of barbiturates should be avoided in patients with what medical condition?
Porphyria
Why are barbiturates of limited availability in the US?
They have been politically associated with the death penalty and thus drug companies do not want their names associated with them
Describe etomidate as an intravenous anesthetic
Potent ultra-short acting hypnotic without analgesic properties
Etomidate modulates signaling at ______ receptors and helps to mediate pain response and _____
GABA [A]; memory
Other uses for Etomidate, other than as an intravenous anesthetic, include _______ and _______
Conscious sedation
Rapid sequence induction for cardioversion
The administration of Etomidate must be followed with the administration of _____ and ______ drugs
Analgesic
Muscle relaxant
An IV injection of Etomidate ____ mg/kg will induce sleep for ____ min
0.3 mg/kg
5 minutes
Potential side effects of Etomidate include (hypotension/hypertension), ____ retention, and suppression of _____ synthesis at the ______ _____
Hypotension
CO2 retention
Suppression of corticosteroid synthesis at the adrenal cortex
What is the MOA of opioids?
Selectively inhibit nociceptive reflexes and induce analgesia through action at the mu receptors
How do opioids interact with substance P? What does this cause?
Inhibits the release of neurotransmitters such as substance P and therefore antagonizes the effect of exogenous substance P
This changes how substance P is received in the CNS.
Morphine, an opioid, is associated with ______ release
histamine
What are potential adverse effects of opioids?
Respiratory depression
Nausea / vomiting
Constipation
What is ketamine used for? Often in what setting?
Induction of dissociative anesthesia
Often for emergency surgical procedures (i.e. ortho, children, and OR adults)
Ketamine acts on receptors in the _____ and the ____ _____
cortex and the limbic system
The onset of action of Ketamine is _____ min
<1 minute
Does ketamine require a lot or a little monitoring after administration?
Ketamine requires minimal monitoring in healthy individuals
What are some adverse effects of ketamine?
Hallucinations, bad dreams, increased muscle tone (very rare, <1% pts)
Is propofol chemically related to other IV anesthetics?
No
At room temperature, what type of solution is propofol?
Oil based emulsion
Propofol acts to potentiate ____ receptor activity and block ____ channels
GABA; sodium
Does propofol have a slow or rapid onset?
Rapid onset of anesthesia
Propofol is frequently used in _____ _____ settings
neuro ICU
Possible adverse effects of propofol include _____, _____, and _____.
Significant respiratory depression, hypotension, and injection site pain
A perfect inhaled anesthetic would have fast onset and offset of action, have a wide safety margin, provide rapid changes in depth of anesthesia, and have no adverse effects in normal doses. Which anesthetic agent meets this description?
NOTHING IS PERFECT, except unicorns, which don’t exist, just like the aforementioned drug
Inhaled anesthetics are used for ____ and/or as an ____. They are not as ____ as other drugs, and thus are not as widely used.
induction; adjuvant; stable
T/F Inhaled anesthetics are lipophilic
True
How are inhaled anesthetics classified?
By their side chains
Inhaled anesthetics act to alter ______ ion channels to (decrease/increase) tissue excitability
neuronal; decrease
Speed of induction of inhaled anesthetics is (directly/inversely) related to solubility in most body tissues
inversely
What are four examples of inhaled anesthetics?
Nitrous Oxide
Sevoflurane
Isoflurane
Desflurane
What are potential adverse effects of inhaled anesthetics? What is a rare adverse effect that we should be careful to monitor for?
Nausea, vomiting
Malignant hyperthermia is rare, but important for monitoring
Patients with what two organ dysfunctions should use inhaled anesthetics with caution?
renal / hepatic dysfunction
Isoflurane is often used because of it’s ability to maintain ______, but it has a _____ _____.
cardiac output; pungent odor (described as musty and ethereal…)
Local anesthetics (reversibly/irreversibly) block nerve conduction around site of administration by inhibiting ____ channels. This (decreases/increases) nerve cell membrane permeability to ____ ions and (decreases/increases) depolarization and (decreases/increases) excitability threshold, preventing the nerve _________ from forming
reversibly; sodium; decreases; sodium; decreases; increases; action potential
Can local anesthetics be used systemically?
Yes
Local anesthetics may be used for infiltration or nerve block prior to certain procedures.
Infiltration is preferred for _____ or _____ procedures. Nerve blocks are preferred for _____ or ____ procedures and for _____ management
Infiltration: Surgical or dental procedures
Nerve block: Surgical or diagnostic procedures and for pain management
Local anesthesia is administered _____ when starting an IV, performing a shave biopsy or placing sutures. Local anesthesia is administered _____ for dental or laceration repair situations, _______ for post-operative pain control, _______ for joint pain, and ______ for nerve blocks
SubQ Submucosal In the wound Intra articular Infiltrative
How are amino amides metabolized?
Via hepatic pathways
What are some examples of amino amides?
Lidocaine
Bupivacaine
Prilocaine
Dibucaine
Which amino amide is used in epidural settings?
Bupivacaine
Which amino amide can be used for suppository pain relief and analgesia associated with hemorrhoids?
Dibucaine
Which amino amide is not usually used in an injectable formation?
Prilocaine
What class of anesthetics should be used in pts who will not tolerate first pass as they remain local?
Amino esters
How are amino esters metabolized?
Metabolized in plasma by plasma cholinesterase throughout the vasculature,
What is the intermediate metabolite of amino esters?
PABA (para aminobenzoic acid)
Administration of amino esters has an associated increased risk of allergy in ___% of the population, which most of the time (does not/does) result in anaphylaxis
~5%
Does not
What are some examples of amino esters?
Benzocaine
Cocaine
Procaine
Tetracaine
Which amino ester is used in dental procedures, with intubation, and called “Hurricane Spray”?
Benzocaine
Which amino ester is used as a 4% topical solution for ENT surgeries? Why?
Cocaine
It is highly vasoconstrictive, which is good for controlling bleeding in the highly vascularized areas of the ears, nose, and throat
Which amino ester is used in eye drops?
Tetracaine
T/F Amino esters are considered “old” or “traditional” agents and are widely used
False; while amino esters are considered ‘old’ and ‘traditional’ agents, they are mostly relegated to topical or niche use
Dose reduction of any anesthetic agent should be considered for what types of patients? (think generally, what ages, what debilities, what diseases, etc)
Acutely ill pts Debilitated pts Very young or elderly individuals Pts w/ significant hepatic impairment Occlusive arterial dz Arteriosclerosis
Use caution with epinephrine if patient has underlying _____ disease
Cardiovascular
CNS (depression/stimulation) is usually noted first, then later, CNS (depression/stimulation) leads to ______ and _____. Amides may not augment the (depression/stimulation) phase, but only the (depression/stimulation) phase of this reaction. If epinephrine is present, it may augment the (depression/stimulation) phase of toxicity with the possible symptoms of _____, _____, _____.
stimulation; depression; respiratory failure and cardiac arrest; stimulation; depression; hypertension, tachycardia, angina
If a patient has reported an allergy to lidocaine, it is possible that the reaction is actually associated with _______
preservatives in multidose vial preparations
Adverse effects of anesthetic medications are usually associated with (decreased/increased) plasma concentrations, _______ dose or rate of injection, ______ in drug clearance, CNS effects such as ______, Cardiac effects such as ______ and ______, Respiratory effects such as _________, a ______ sensation, skin _______, tissue ______/______, and neuritis.
Adverse effects of anesthetic medications are usually associated with (increased) plasma concentrations, (excessive) dose or rate of injection, (reduction) in drug clearance, CNS effects such as (sz), Cardiac effects such as (bradycardia) and (arrhythmias), Respiratory effects such as (respiratory arrest), a (burning) sensation, skin (discoloration), tissue (necrosis)/(sloughing), and neuritis.
What are some potential advantages or regional anesthesia over systemic anesthesia?
Anti inflammatory effects i.e. decreased cytokine formation and decreased tissue inflammation
Faster functional recovery
Cardiopulmonary effects
GI effects (less stasis/ileus)
Improved coagulation effects (prevents venous stasis and VTE occurrence)
How is epidural anesthesia administered? Where is its primary site of action?
Administered by injecting local anesthetic into the epidural space, primary site of action in the spinal nerve roots
What is the major difference between epidural anesthesia and spinal anesthesia?
Higher concentrations of anesthetic may be achieved after epidural absorption
Which epidural anesthetic is longer acting and has some use in pain management situations?
Lidocaine
Where is spinal anesthesia injected?
The CSF in the lumbar space
Who should you avoid administering spinal anesthesia to?
pts on blood thinners
Which three medications are most commonly used in spinal anesthesia?
Lidocaine, bupivacaine, and tetracaine
Spinal anesthesia is most commonly used in surgeries involving what parts of the body?
lower abdomen, lower extremities, and perineum
What are potential adverse effects of spinal anesthesia?
Infection, hematoma, and HA
What are risk factors that affect pain control in peri-operative settings? (hint: similar to pts who will have post operative N/V)
Preoperative pain Anxiety Genetics Opioid tolerance Female gender
In regards to the pathophysiology of pain, there are both ______ and _____ components.
inflammatory and neuropathic
What are the three mechanisms of chronic neuropathic pain?
Peripheral component, central component, central plasticity
Describe the 3 central mechanisms of chronic neuropathic pain:
- Peripheral component, multiple inflammatory mediators responsible for (negative/positive) sx of _____, _____, and _____
- Central component, mediated through the ____ ____ neurons
- Central plasticity, where excess excitatory transmission and loss of (inhibitory/excitatory) transmission lead to barrage of CNS input from the _____ _____ of the spinal cord
- Peripheral component, multiple inflammatory mediators responsible for (positive) sx of (hypersensitivity), (allodynia), and (erythema)
- Central component, mediated through the (dorsal horn) neurons
- Central plasticity, where excess excitatory transmission and loss of (inhibitory) transmission lead to barrage of CNS input from the (dorsal horn) of the spinal cord
Nociceptive stimulus from any source (thermal, mechanical, or otherwise) causes a release of multiple ______ substances into the affected tissue. This leads to _____ sensitization that supply affected area, a phenomenon known as peripheral sensitization. The CNS also becomes sensitized due to afferent input to the CNS, known as ______ sensitization.
Nociceptive stimulus from any source (thermal, mechanical, or otherwise) causes a release of multiple (inflammatory) substances into the affected tissue. This leads to (nerve) sensitization that supply affected area, a phenomenon known as peripheral sensitization. The CNS also becomes sensitized due to afferent input to the CNS, known as (central) sensitization.
Preventive analgesia focuses on ____, ____, and ____ of analgesic therapy
timing, duration, and efficacy
Preventive analgesia preserves total body _____ and enhances post-operative _____ and _____.
nitrogen; recovery and rehabilitation
Dexmedetomidine and clonidine are _____ agonists
Alpha 2
______ are considered the mainstay of peri-operative pain management, and judicious use offers analgesia through central and peripheral mechanisms.
Opioids
_____ have been demonstrated to reduce opioid requirements of dosing and reduce side-effects of itching, constipation, and drowsiness. If bleeding is a concern, many suggest short-term use of ______ as these agents are more selective
NSAIDs
COX-2 inhibitors
_______ in small doses (0.15mg/kg IV) may reduce opioid requirements and reduce progression to chronic pain
Ketamine
_______ has shown opioid-sparing effects and increased post-op anesthesia, though does not limit opioid-related adverse effects
Gabapentin
What are some examples of NSAIDs that may be used to reduce opioid requirements?
Ketorolac, ibuprofen, and naproxen
In a pt with healthy kidney function, what is the absolute max amount of time that a pt can take Ketorolac?
5 days
What are some examples of COX 2 inhibitors that may be used to reduce opioid requirements in pt with bleeding concerns?
Celecoxib
Dexmedetomidine is used in inpatient ICU settings for _____ and in anesthesia for brief procedures due to ______ ______
sedation; administration difficulties
Dexmedetomidine has ____, ____, and _____ properties
Sedative, anxiolytic, and analgesic
What are some possible adverse events of Dexmedetomidine that require monitoring?
monitor HR, BP, sedative effects
What are potential risk factors for developing post operative nausea and vomiting (PONV)? (hint: similar to pts in operative pain control)
Female gender Motion sickness / previous PONV Non-smoking status Post-operative use of opioids Use of inhaled anesthetics (nitrous oxide and other volatile agents) High-dose neostigmine
By what percent does each risk factor increase a pt’s risk for developing PONV?
18-22%
Post operative nausea incidence is ___-___% and vomiting incidence is ___-___%
22-38% N
12-26% V
Anesthesia technique factors that affect PONV include….
Inhalation agents
Nitrous oxide
High-doses of neostigmine
Intra- and post-operative opioids
Surgical risk factors that affect PONV include….
Longer duration of surgery, types of surgery
T/F A multimodal approach to PONV is best
True
A multimodal approach constitutes _____ and ___-_____ therapy
pharmacologic and non-pharmacologic
Preoperative options for PONV include….
BDZ (for anxiolysis) Compassionate interaction w/ staff Aprepitant (Emend) Dexamethasone steroids Pre-hydration 1L NS or LR
Intra-operative options for PONV include….
Use of correct regional anesthetics Propofol Analgesia (non-opioid) Ketamine Anti-emetic therapy
What are some examples of medications that can be used to treat PONV? (classes and examples of specific names)
Serotonin antagonists (Odansetron) Neurokinin inhibitors (Aprepitant) Steroids (Dexamethasone) Antihistamines (Dimenhydrinate [1st gen antihistamine], promethazine) Butyrophenones (Droperidol) Benzodiazepines
What are some examples or serotonin antagonists that can be used for PONV?
Ondansetron
Granisetron
Which serotonin antagonist is used in the tx of N/V in CA pts?
Granisetron
At what receptor do serotonin antagonists act?
5HT-3 receptor
What are some potential adverse effects of serotonin antagonists?
Headache Diarrhea Constipation Arrhythmia Serotonin syndrome
When neurokinin inhibitors are administered pre-anesthesia, they reduce nausea and vomiting up to ____ hours after surgery
48
Neurokinin inhibitors are commonly used prior to ____ surgeries
abdominal
Aprepitant is a neurokinin inhibitor that blocks _____ production
Substance P (this data came from chemotherapy pts)
What are some potential adverse effects of neurokinin inhibitors?
Dizziness
Diarrhea
Headaches
Weakness
While steroids have an unclear mechanism of action, they may affect _____ in the brain
prostaglandins
_______ is a common steroid, available intravenously and in long term NV w/ pts w/ failure to thrive
Dexamethasone
Possible adverse effects of steroids include…
Dizziness
Mood change
Nervousness
______ work at emesis center and chemoreceptor trigger zone (CTZ) to reduce vomiting
1st gen antihistamines
What are some possible adverse effects of 1st generation antihistamines?
Sedation!
Confusion
Dry mouth
Urinary retention
_______ work at the chemoreceptor trigger zone (CTZ) to block nausea / vomiting and at the D2 receptor
Butyrophenones
Droperidol, a Butyrophenone, is not utilized, except in a ____ or _____ ____ setting
hospital or ambulatory surgery
Adverse effects of Butyrophenones include…. Which of the adverse effects carries a black box warning?
Prolonged QTc interval (black box warning)
Hypotension
Tachycardia
Extra-pyramidal sx
T/F Prevention and multimodal approach is necessary to reduce post-operative nausea / vomiting
True
T/F Systemic agents are most commonly used in nerve and infiltrative blocks to improve patient experience and pain control
False; Local agents are most commonly used
The dosing recommendation for Lidocaine is as follows: Concentration: \_\_\_-\_\_\_% Max dose: \_\_\_-\_\_\_ mg/kg (max: \_\_\_\_ mg) Onset: \_\_\_\_ min Duration: \_\_\_-\_\_\_ hours
Concentration: 1-2%
Max dose: 4.5-5 mg/kg (max: 300 mg)
Onset: <2 min
Duration: 0.5-1 hours
The dosing recommendation for Lidocaine w/ epinephrine is as follows: Concentration: \_\_\_-\_\_\_% Max dose: \_\_\_ mg/kg (max: \_\_\_\_ mg) Onset: \_\_\_\_ min Duration: \_\_\_-\_\_\_ hours
Concentration: 1-2%
Max dose: 7 mg/kg (max: 500 mg)
Onset: <2 min
Duration: 4-6 hours
The dosing recommendation for Bupivicaine is as follows: Concentration: \_\_\_% Max dose: \_\_\_-\_\_\_ mg/kg (max: \_\_\_\_ mg) Onset: \_\_\_\_ min Duration: \_\_\_-\_\_\_ hours
Concentration: 0.25%
Max dose: 2.5 mg/kg (max: 175 mg)
Onset: 5 min
Duration: 2-4 hours
The dosing recommendation for Bupivicaine w/ epinephrine is as follows: Concentration: \_\_\_% Max dose: \_\_\_\_ mg Onset: \_\_\_\_ min Duration: \_\_\_-\_\_\_ hours
Concentration: 0.25 %
Max dose: 225 mg
Onset: 5 min
Duration: 3-7 hours
The dosing recommendation for Procaine is as follows: Concentration: \_\_\_-\_\_\_% Max dose: \_\_\_-\_\_\_ mg/kg Onset: \_\_\_-\_\_\_ min Duration: \_\_\_-\_\_\_ hours
Concentration: 0.25-0.5%
Max dose: 350-600 mg/kg
Onset: 2-5 min
Duration: 0.25-1 hours
What is the equipotent dosing of Morphine and its corresponding duration of action?
Morphine: 1-2mg, 90 min
What is the equipotent dosing of Fentanyl and its corresponding duration of action?
Fentanyl: 0.05-0.1mg, 30 min
What is the equipotent dosing of Sufentanil and its corresponding duration of action?
Sufentanil: 0.005-0.01mg, 15 min
What is the equipotent dosing of Hydromorphone and its corresponding duration of action?
Hydromorphone: 0.1-0.2mg, 60 min
