How to avoid common pitfalls with anesthetic monitoring in dentistry cases

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“Just plan your butt off,” said Katrina Lafferty, BFA, RLAT, CVT, VTS (Anesthesia/Analgesia). Speaking at the 2022 Atlantic Coast Veterinary Conference in Atlantic City, New Jersey, Lafferty delivered a lecture on anesthetic considerations for dentistry cases, emphasizing the unpredictability of dentistry cases that can be mitigated by being prepared for as many scenarios as possible.

Anesthetic monitoring during a dentistry case, Lafferty said, requires preparedness and potentially even creative problem solving at times. During the presentation, Lafferty walked through what to expect while performing anesthetic monitoring and shared some pearls for each step.

Pulse oximetry

Pulse oximetry measures oxygen saturation of hemoglobin, and Lafferty said she is looking for 95 or greater to ensure the lungs are oxygenating efficiently. However, she warned it can be misleading in cases where the patient is profoundly anemic or vasoconstricted from receiving dexmedetomidine. In dentistry cases where the mouth may be off limits, Lafferty recommended: “We actually keep a flat reflectance probe in our dental suite and that's what we use on almost all of our animals, because you can shave the base of the tail, put the flat probe on there, use some back wrap, and then you don't have to fiddle in the mouth constantly to try to get this to work.” She advised that for those who don’t have a flat reflectance probe, a rectal probe can be used in the same way in smaller animals.

Capnometry

A capnometer is a simple, noninvasive tool to monitor inspired and expired amounts of carbon dioxide. Lafferty noted the great thing about capnometers is that they will tell you immediately if the person cleaning the mouth has accidentally disconnected the hoses or there is an obstruction. Her tip here is to use side-stream capnometers in dentistry cases, as inline capnometers are not built to withstand all the fluid, blood, and mucus involved and will get ruined.

Electrocardiography

The electrocardiogram measures electrical activity in the heart and is useful for monitoring common arrythmias or abnormalities that can be linked to electrolyte imbalances, levels of anesthesia, and ventilation issues. However, Lafferty advised, “It doesn't tell you that your patient is actually alive; it just tells you what the electrical conduction of the heart looks like.”

Blood pressure monitoring

Direct arterial pressure monitoring is the best way to obtain constant, accurate, real-time information about blood pressure, Lafferty said. However, she recognized that it is not always feasible or realistic. “It is never wrong to put a Doppler on your patient,” Lafferty said.

She explained that clinicians have gotten away from using a Doppler because they might feel like it’s “low tech,” but there are advantages to its simplicity. Lafferty said, “Viscosity isn't going to trick it; arrhythmia isn't going to trick it; profound hypotension isn't going to confuse it.”

Reference

Lafferty K. Say “Ahhh”—Anesthetic Considerations for Dentistry Cases. Presented at: Atlantic Coast Veterinary Conference; October 10-12, 2022: Atlantic City, New Jersey. www.dvm360.com/2022-acvc-proceedings