BIS Monitors

The BIS monitor is a kind of "mini EEG" that gives a numerical readout that is supposed to measure the depth of anesthesia or sedation.

I did use them where I used to work, but the small hospital where I now work does not have them. They are a useful adjunct to anesthesia, and do, if used properly, give you something concrete on which to gauge anesthetic administration. When they were available to me, I most often used them on cases where depth of anesthesia was important (neuro cases where you needed to wake the patient), monitoring brain activity in cases where stroke was a possibility (carotid endartarectomies under general anesthesia), and in cases with a high incidence of post-operative recall (open heart procedures).

They should not be used to replace your own senses and judgement, however. Like any other monitor, you cannot allow the BIS monitor to capture your attention over actually watching the patient.

Kevin McHugh

I don't need a monitor to tell me when the patient is moving, everyone in the operating room thinks it is their god-given duty to tell me. Of course I am being facetious, but in my practice a BIS monitor would not be very useful. I can see it being used in neurosurgery or spinal surgery, where depth of anesthesia is important to the surgical procedure.

My senses are still the best monitors I have--my ears contantly attuned to the heart and breath sounds, my eyes watching the surgery and the patient's response to stimuli, my hands to feel the patient's skin and to hold their hand. My agent monitor was not working well today, so I even used my nose to smell the isoflurane in the circuit. That is something I rarely do, but the patient had a strange tachycardia and I wanted to make sure it wasn't from light anesthesia. The monitors are great, but I can do anesthesia without them.

YogaCRNA

We use BIS monitors in our ICU for patients who are paralyzed and sedated to help monitor their level of sedation. They are really useful in those cases, but we have also had problems with accuracy, particularly in patients whose foreheads are very edematous.

The representative informed us that there are new forehead strips for the BIS monitor that will decrease the artifact- this may improve the functioning of the BIS.

My sister works at a 650 bed hospital which uses them and says that as long as they are working right, they are quite helpful in recognizing that a patient is sedated enough and may simply need more pain medication during surgery in response to increased heart rate or something like that. She is a PACU nurse so only knows about them in a limited way. In my humble opinion, when working with any machine it's prudent to be sure it's operating porperly and to use our brains and intuition at all times.

From what I have seen the newer PSA monitors are better than the BIS monitors.