5 Things to Avoid Doing with Your Anesthesia Monitoring Equipment

There are a number of reliable and user-friendly anesthesia vital sign monitors available to the veterinary community. Many are multi-parameter monitors that include combinations of ECG, body temperature, non-invasive blood pressure, pulse oximetry and capnography measurements conveniently assembled into one unit. Alternative options are single-function devices. Neither configuration is superior: there is currently no evidence that multi-parameter monitors offer better patient safety than single-function monitors.

A monitoring device cannot replace the anesthetist since anesthetic depth assessment which is key to anesthesia safety, requires more than a machine that goes “PING”. To my mind, the most reliable monitor is the anesthetist who selects devices that enhance and complement their monitoring skills.

As an anesthesiologist who has spent the last 30 + years instructing technicians and veterinary students as well as seasoned practitioners, I have observed certain common habits that are detrimental to getting the most out of our monitoring dollars. Here are 5 of them:

1. Buying a unit without testing it first.

Don’t buy anything without first test driving it. This will allow your team to evaluate the monitor’s menu, screen size and other subjective user-friendliness features that make one device a better choice than others for a given hospital setting. Also, the test drive period allows you to get to know the distributor/manufacturer and evaluate what to expect from after-sales service, support and repair.

2. The “deer in the headlights” scenario.

It may be tempting to introduce a monitoring device that measures the maximum number of parameters. After all, the more you monitor the safer the patient, right? This may not be the case if the anesthetist is suddenly confronted with a large array of alarms, flashing numbers, waveforms and graphic displays that they cannot fully interpret or understand. More time will be spent troubleshooting alarms and trying to understand the screen information than paying attention to the patient which is counterproductive when it comes to anesthesia safety. It is wiser to select monitoring parameters that your team fully understands. For example, if you are introducing capnography to your anesthesia toolbox, be sure to familiarize yourself with an interpretation of the various normal and abnormal capnograph waveforms well as inspired and expired carbon dioxide levels. Otherwise, the capnograph is just noise. Many reputable anesthesia monitor manufacturers and distributors offer training and instruction on the interpretation of the various monitoring parameters.

3. Dismissing your monitor as “broken” when it is not providing measurements.

This can be the first sign of serious even life-threatening hemodynamic instability and can happen even with healthy patients (think anaphylaxis or adverse drug reaction). When a monitor is not providing you with timely heart rate or blood pressure measurements, rather than dismiss the situation as machine error, take a moment to assess pulse strength and quality by placing your index finger on the dorsal pedal or other peripheral (not the femoral) pulse and applying digital pressure. If the pulse feels weak, is easily obliterated by finger pressure or if it is absent, then you know that your patient needs immediate intervention and that the monitor is not “malfunctioning”.

The same goes for low hemoglobin saturation readings. If the pulse oximeter reading drops, make sure that you visually assess mucous membrane colour. It might be a spurious reading but you need to be sure. Also, the more often you inspect the mucous membrane colour, the better you will be at detecting subtle colour changes that indicate a decrease in your patient’s oxygenation and correlate with a decrease in hemoglobin saturation as reported by the pulse oximeter.

4. Limiting monitoring equipment used to the operating suite only.

Some anesthesia monitoring consoles and their cables can be bulky or heavy and are not conveniently portable. This presents an anesthesia safety and standard of care issue if your hospital relies on only one monitor and that monitor “lives” in the operating room. Patients requiring anesthesia delivery outside of the OR deserve the same monitoring vigilance as those undergoing procedures in the surgical suite. If the patient is unconscious it needs to be vigilantly and continuously assessed. Think of the older dentistry patient undergoing a lengthy procedure, or the trauma victim requiring x-rays.

5. Delaying placement of monitors until your transfer to the OR

This ties in with # 4 above. If a patient is rendered unconscious, intubated and surgically prepped in one room and then transported to the operating suite for its procedure, it is unwise to wait until you are in the OR to place the monitors. It’s best if the monitor is moved to the patient’s side before anesthesia delivery starts. Otherwise, you may miss signs that the patient is unstable under anesthesia which will delay intervention and correction. Also, picture the frustration and disruption when transferring to the OR and being unable to get the monitors to function properly as the procedure is getting underway. Not ideal.

Consider anaphylaxis: It can occur during the prep period and it may affect the healthy patient undergoing an elective procedure, a scenario when typically vigilance is reduced because the patient is healthy. If you wait until you are in the OR to identify this problem, you have lost an important opportunity to correct the situation which has become lie threatening.