Anesthesia for the dentistry patient
Keeping Your Patients Safe Under General Anesthesia
Tasha McNerney, BS, CVT, CVPP
Often, when asked why veterinarians do not recommend dental care earlier for their patients, they commonly respond that the benefit is not worth the risk of anesthesia. Unfortunately, the patient suffers in the long run. Without appropriate preventive care, inevitable periodontal disease flourishes in our small animal patients.
So, as technicians, what can we do to ensure our Drs know that we reduce anesthetic risk to a bare minimum? First, we have to get out of the mind-set that “dentals” are an add-on procedure. Dentistry requires its own case management and planning. In many cases, dental cases are older patients in a state of chronic infection.
The anesthesia records should be read in advance to ensure that all preoperative bloodwork and cardiac status is good and if not, a plan for support be at the ready. If a murmur was heard on exam, was a cardiac work up recommended? If so, was that completed and do you have the report? Does this patient have increased renal values and is there a plan to preload with fluids prior to anesthesia? Everything this case needs should be carefully planned and provided.
Pressure test your anesthesia machine prior to each day. Make sure your equipment is all working properly before you induce any
Consider preoperative ECG’s prior to anesthesia. Often auscultation does not suggest the presence of VPCs and a baseline ECG is valuable before choosing the right drugs or deciding if a cardiac consult is now recommended and rescheduling is prudent.
Once all pre-planning is complete, then here are some things to keep in mind to optimize patient safety:
1. Most important: there should be a separate anesthetist for each dentistry. Someone needs to monitor all parameters every 5 minutes to note trends so that they can be corrected before it becomes an issue while maintaining protocols for discontinuing the procedure.
2. Temperature (discontinue if you cannot maintain a body temperature of 96 degrees F or greater and not higher than 102.
a. HotDog Patient Warming System
b. Baer Hugger
c. Gaymar Water Circulating Pump
d. Patient not on a cold grate. Use blankets
e. Bubble wrap
f. IV line warmers
g. Avoid thermal burns at all costs. Extreme caution with rice bags, heated fluid bags, plastic microwavable warmth discs. Do not leave against an unconscious animal.
3. Pulse ox: This can be difficult on dentistry patients since usually the tongue is where the sensor is commonly placed. There are a variety of sensors; pediatric, tongue, “C” clamp, and a rectal sensor. Since patients are on 100% O2, a reading lower than 95% should be investigated until corrected.
4. Blood pressure: cuff size should be properly selected. The front leg is most accurate and multi-parameter NIBP usually give a pretty accurate reading. However, a Doppler and a manometer is the most accurate method for ascertaining the actual reading.
5. Capnography: This technology provides the anesthetist with a capnogram. This provides valuable information about:
a. Respiration rate
b. Respiration rhythm
c. Shape of form is diagnostic or helps troubleshoot anesthetic issues before you realized there were issues
i. Bronchial intubation
ii. Equipment disconnection
iii. Airway obstruction
iv. Exhausted CO2 absorber
v. Leaks in tubing
6. An all too common complication from dental cases are tracheal tears. This is usually from improper intubation techniques. Measure your endotracheal tubes. Put the Murphy’s eye of the tube at the thoracic inlet and then place your tie at the corner of the mouth.
a. Use clear plastic, high volume, low pressure cuffs
b. Pre-inflate the cuff and lubricate with lubricant
i. Make sure that the cuff expands uniformly and it doesn’t bleb to one side
c. Deflate and place, use a laryngoscope and lidocaine if needed.
d. One person inflates the cuff while the other person closes the pop-off valve and gently squeezes the O2 reservoir bag. Stop inflating once you no longer hear air escaping around the cuff. You should be able to hold 10mmHg of pressure. Re-open pop-off valve.
7. Employ regional nerve blocks in an attempt to reduce inhalant anesthesia to preserve blood pressure. The most commonly utilized regional nerve blocks for dentistry include the mandibular block , the maxillary block, and the infraorbital block.
8. No use of spring loaded mouth gags. Recent studies suggest possible blindness where the ocular nerve were not supplied with blood secondary to pinched vessels from mouth gags.
In closing, it is our responsibility to provide the safest anesthetic experience for our patients. Not recommending professional dental care only leaves these patients at risk for infection, pain and a shorter life span.