Exam 1 - Emergent Procedural Anesthesia Flashcards
what is the goal of sedation?
safely provide maximum patient comfort to perform a stressful procedure
to cause minimal complications to the patient & minimal risk to the staff involved
what are some examples when sedation alone may not be the best option compared to general anesthesia?
major invasive painful procedures
fractious patients that may pose a safety risk for staff
patients at high risk for aspiration
procedures in the oral cavity
endoscopy & gastroscopy
high-risk critically ill patients
what are the limitations of sedation?
arousable patients
protective reflexes are delayed
intubation not possible
limited oxygen & ventilatory support isn’t possible
limited monitoring
what are the most common potential complications seen in emergent procedural anesthesia? how are they managed?
hypoxemia - oxygen supplementation
apnea - intubation & assisted ventilation
aspiration pneumonia - decrease the risk of regurgitation/vomiting with fasting & anti-emetics, place head higher than the stomach with mouth down to drain any content or use suction
bradycardia with hypotension - anticholinergics (glycopyrrolate & atropine) and/or drug reversal
what are the statistics of the risk of death associated with anesthesia & sedation in humans, healthy dogs, & healthy cats?
humans - 0.005%
healthy dogs - 0.009%
healthy cats - 0.11%
how many times does the risk of death increase for urgent/emergency anesthesia/sedation in sick dogs & cats?
dogs - 5X risk
cats - 10X risk
what are some examples when we may use just sedation for a patient?
diagnostic imaging
transport & handling
minor procedures with minimal pain
what does sedation provide to our patients?
induces a sleep-like state, relaxes the animal, reduces anxiety, & decreases their reflexes
is sedation safer than general anesthesia?
not necessarily - you can’t intervene with ventilatory support because no intubation, limited monitoring & support compared to general anesthesia
what are the big differences between sedation & general anesthesia?
sedation - animal is sleepy but still arousable, delayed protective reflexes, can’t intubate, limited support, & limited monitoring
general anesthesia - animal is unconscious, no protective reflexes, can intubate the patient, can provide full support & monitoring
what equipment should you have set up for an emergency sedation?
oxygen, monitoring supplies, supplies for intubation & ventilation, emergency drugs & antagonists worked up
what should be done as far as patient prep for an emergency sedation?
get the animal’s clinical history & PE
stabilization & anesthesia
IV catheter placement
minimize risk of aspiration
draw up a sedation plan
what parameters should you be monitoring for a patient that is under emergency sedation/anesthesia?
level of sedation
respiratory rate & effort
SpO2
ETCO2 capnograph trends
ECG & heart rate
pulse rate & quality
blood pressure
mucus membrane color & CRT
patient temperature
what should help you guide you when deciding drug choices for emergency sedation/anesthesia?
balanced sedation
administration - IV or IM
faster onset of action & shorter duration
start with low doses & pick drugs that can be antagonized/reversed
locoregional anesthesia if possible
what drugs are commonly used for sedation in emergency sedation/anesthesia?
alpha-2 agonists
opioids
benzodiazepines
alfaxalone
dissociative agents
propofol
which opioid is best for mild pain? what about severe pain?
mild pain - butorphanol, mu antagonist & kappa agonist
severe pain - mu agonists, methadone, hydromorphone, & fentanyl
mild to moderate pain - mu partial agonist, buprenorphine
what are some indications for using opioids in emergency sedation/anesthesia?
analgesia
sedation
anti-tussive
has an antagonist - naloxone
can be given IV/IM/CRI
what are some indications for using benzodiazepines such as midazolam & diazepam in emergency sedation/anesthesia?
muscle relaxation
minimal cardiovascular effects
anti-convulsants
has an antagonist - flumazenil
can be given IV/IM/CRI
what are some indications for using alpha-2 agonists, such as dexmedetomidine & medetomidine + vatinoxan, in emergency sedation/anesthesia?
sedation
analgesia
muscle relaxation
has an antagonist - atipamezole
can be given IV/IM/CRI
should you use acepromazine in a patient with questionable cardiovascular stability? why?
no - it causes peripheral vasodilation & drops BP & body temp
what are some indications for using acepromazine in emergency sedation/anesthesia?
tranquilization
muscle relaxation
some anti-emetic effects
can be given IV/IM
what are some indications for using propofol in emergency sedation/anesthesia?
low dose needed for sedation
muscle relaxation
IV exclusive
anti-convulsant effects
what are some indications for using alfaxalone in emergency sedation/anesthesia?
low dose needed for sedation
muscle relaxation
IV/IM/CRI
may see tremors during recovery
what are some indications for using dissociative agents, such as ketamine & telazol, in emergency sedation/anesthesia?
low dose needed for sedation
analgesia
telazol is useful in fractious cats
can be given IV/IM/SC/IP/CRI/transmucosal
what are some patient factors that may complicate emergency sedation/anesthesia?
fractious or fearful patient
very painful animal
animal has a heart murmur
what are some considerations you should think about prior to using opioids in emergency sedation/anesthesia?
decreases heart rate
dysphoria
respiratory depression
may cause nausea/regurgitation/vomiting
what are some considerations you should think about prior to using benzodiazepines such as midazolam & diazepam in emergency sedation/anesthesia?
no analgesia provided
unpredictable effect when given alone
respiratory depression
what are some considerations you should think about prior to using acepromazine in emergency sedation/anesthesia?
avoid giving to patients with cardiovascular instability
causes peripheral vasodilation
decreases BP & body temperature
splenic relaxation
prolonged onset of action & duration
no analgesia
no reversal
what are some considerations you should think about prior to using propofol or alfaxalone in emergency sedation/anesthesia?
IV must be given slow to effect to avoid causing apnea
potential to accidentally induce anesthesia
dose-dependent respiratory & cardiovascular depression
no reversal
no analgesia
what are some considerations you should think about prior to using dissociative agents, such as ketamine & telazol, in emergency sedation/anesthesia?
may need to combine with a muscle relaxant
sympathetic cardiovascular stimulation
apneustic breathing
potential to induce anesthesia
may see excitation during recovery
pain on IM injection
no reversal
what are the main differences between deep sedation & general anesthesia?
deep sedation - patient can still be arousable especially following repeated or very painful stimuli, delayed but present protective reflexes
general anesthesia - absent purposeful responses, absent spontaneous posture, & absent protective reflexes
what is included in stabilizing your emergency sedation patient prior to the start of the procedure?
fluid balance & cardiovascular status should be assessed & corrected/supplemented
what is the benefit of placing an IV catheter in your patient for emergency sedation/anesthesia?
essential to allow for the slow administration to effect of drugs so that the minimal amount is used
IV administration provides a more rapid onset & shorter duration of action
why use a pulse oximeter on your patient for emergency sedation/anesthesia?
SpO2 indicates the presence & severity of hypoxemia earlier than cyanosis
<95% or cyanosis prompts immediate assessment for the need of intubation, 100% oxygen, & ventilation
what is the onset of action of acepromazine?
15 minutes following IV administration - less preferable for emergency situations because it is so prolonged
what side effects are associated with dexmedetomidine?
bradycardia, bradyarrhythmia, & biphasic effect on blood pressure (vasoconstriction followed by a normal or low blood pressure)
what two groups of drugs used for emergency sedation/anesthesia have limited cardiovascular effects?
opioids & benzodiazepines
why should you not use ketamine in a patient with head trauma?
ketamine causes the release of catecholamines which increase the heart rate, blood pressure, & intracranial pressure
what drugs would you use for an emergency sedation of a patient with a heart murmur?
combo of benzodiazepine & opioid - minimal cardiovascular effects
what drugs would you use for an emergency sedation of a very painful patient?
mu-opioid for pain, dexmedetomidine, & ketamine
what drugs would you use for an emergency sedation of a fractious/fearful patient?
alfaxalone or ketamine - induction agents that you can give IM to produce a more reliable sedation
