14. Dental Anesthesia Flashcards
What are some anesthetic considerations for dentals?
aspiration pneumonia, regurg, length of procedure, hypotheria, mouth gags, eye trauma, post-op, deafness post-op
Always secure and protect the airway, besides the obvious, why is it important?
inc risk of aspiration - fluids, tartar and debris collect in the back of the mouth oral procedures
regurg risks inc due to pharyngeal stimulation - gauze packing, x-rays, extracting and cleaning molars
ETT disconnect, extubation, or teacheal trauma - manipulating the oral cavity during cleaning and extractions, and patient position changes multiple times during the procedure
How can we prevent airway complications?
Know ETT length at intubation, inflate ETT cuff but do not over inflate
pharyngeal packing w/ gauze
use capnograph if available
disconnect patient from breathing circuit when repositioning
recheck inflation of ett when patient is repositiioned
What is pharyngeal packing?
moisten gauze before placement to avoid irritation of MM
don’t pack too tightly, can cause the tongue to swell
need to be sure that all gauze is removed prior to extubation
Tie gauze to Ett or leave ends visible from outside the mouth
Why do we use capnograph and ETT’s?
capnography can be used to assess patency of airway and to confirm correct placement of the ETT (ex. esophageal intubation)
Helps to avoid and detect obstruction, ETT cuff leaks, disconnect, or extubation of ETT
Why is having a cuff for an ETT
all dental procedures should be performed w/ a secure, properly inflated cuff ETT
check ETT for leaks prior to intubation
red rubber ETT is not ideal bc the pilot balloon can snag and deflate accidentally
What are some complications associated w/ procedure legnth
hypothermia
repeat dosing of analgesics (opioids, local blocks)
patient positioning - arthritis, compression of limbs or nerves, atelectasis of lungs)
organ damage due to prolonged hypotension
try to minimize time under anesthesia - inc anesthetic time = inc anesthetic risk
What might cause an increased risk of hypothermia?
geriatric, malnourished, or under-weight patients
soaking head w/ water coming from ultrasonic equipment
monitor temp regularly and keep patient warm!
What is hypothermia?
temp maintained btw 37.5-38.5
actively warm patient thruout procedure w/ warm water bottled, bair hugger, hot dog units, warm water blankets
take care not to cause burns due to heating devices
What are thermal burns?
burns due to heating devices can show up days after the procedure
burns can be quite extensive and require significant medical care to recover from
What is the relationships btw mouth gags and cats?
spring held mouth gags can cause cerebral ischemia and blindness in cats
post op px guarded - vision may return 1-2wks
mouth can be held open by hand
What are some alternative mouth gags that can be used?
if a mouth gag must be used, either cut off a piece of ETT, cut a needle cap or use a 1ml syringe cut to length
these need to be shorter than conventional mouth gap to not cause the same problem
Why must we monitor eyes closely?
dental debris can deflect into the eyes
surgeon may have their hands inadvertently into the eye socket (proposed eye, oculocardiac reflex)
lubricate eyes every 15 m, don’t forget about post-op care
What is post-op deafness?
unknown cause but associated w/ geriatric patients
Uncommon but can be complication of dentals or ear cleanings
deaffness was permanent
important to keep in mind for post-op follow-up
Why are dental patients at a higher ASA risk than other patients?
There is a direct relationship btw age and dental dz
geriatric patients are most common mental patients (prophylaxis uncommon)
some systemic dz’s are associated w/ dental dz
proper case mgmt is essential to a healthy, positive patient outcome
What are some diseases associate dw/ dental disease?
heart dz (murmurs progressing to heart failure)
Renal failure (Common in cats)
Diabetes
potential for systemic infection
Malnutrition
immunodeficiency diseases
Why might we have an anesthetic protocol for a routine dental?
due to inc risk of concurrent diseases; a thorough hx, Pe and pre-anes. dx prior to procedure is vital
perform an oral exam: note any difficulty opening the mouth, any oral masses, is the patent guarded or painful during oral exam
pre-anes dx may include: up to date blood work and urinalysis, thoracic radiographs, echocardiogram and ECG (heart work-up)
Should we premed for dentals?
YES - pre emptive analgesia for all dentals, even if it is just a cleaning.
use Mu-opioids (hydro or methadone)
Depending on systemic dz of the patient, a sedative can be added to the premed to dec the amount of induction and inhalant required for the procedure
Why might we induce?
for pre-oxygenation (difficult intubation, geriatric)
all patients under-going dental procedures should be intubated and airway should be protected using a cuffed ETT
induction drugs are dependant on concurrent diseases but standards protocols are: alfaxalone, propofol or ketamine/diazepam IV to effect
How do we maintain an animal under anesthesia during a dental
- Patient should be at a good plane of anesthesia before preforming
oral exam or radiographs to avoid gag reflex or regurgitation - Minimum monitoring includes: blood pressure, temperature, heart
rate and respiratory rate regularly throughout the procedure - Add more equipment depending on the patient: capnograph, ECG,
mechanical ventilator, pulse oximeter - Use a balanced, multimodal anesthesia to decrease need for
inhalant anesthetic and its side effects and to control pain
throughout the procedure
What is intraop analgesia?
top-ip opioid as needed
local anesthetic blocks using bupivacaine
blocks can be performed multiple times if the local wears off or the block does not work well
Calculate safe and toxic doses of local anesthetic for all patients
in feline patients, need to take into account lidocaine used during intubation
How is recovering for dentals?
clean and check the back of the mouth prior to deflating ETT and extubating the patient
Remove gauze packing in the back of the mouth
extubate with ETT partially inflated (controversial)
elevate neck w/ nose down to help drain fluid from mouth (ex. excessive or continued bleeding from extractions)
* Monitor patient closely for the first few hours of recovery
* Assess temperature and actively warm the patient until
temperature is > 37.5 ̊ C
* Recheck that patient is maintaining its temperature
* Perform a pain assessment and repeat analgesia as
needed
