Many strategies have been developed to monitor perioperative anesthesia depth. Bispectral
index (BIS) is a monitor that analyzes electroencephalogram (EEG) data and produces a
numerical value. This value indicates the patient's level of consciousness and helps evaluate
the depth of anesthesia. BIS is a routinely used monitor that continuously monitors the
patient's state of consciousness during anesthesia. In this way, the depth of anesthesia can
be controlled more precisely (1). When the level of consciousness is deep, the BIS value
decreases and increases as the surface is approached. With this feature, it ensures that the
patient's depth of anesthesia is kept at an optimal level and adjusted when necessary. This
may help minimize anesthesia-related complications(2). BIS alone may not be sufficient to
evaluate the depth of anesthesia. It should be used in conjunction with other clinical
findings and monitors. Nowadays, anesthesia depth monitoring is a widely used method and is
performed routinely in our clinic.
Many strategies have been developed to monitor perioperative anesthesia depth. BIS is a
monitor that analyzes electroencephalogram (EEG) data and produces a numerical value. This
value indicates the patient's level of consciousness and helps evaluate the depth of
anesthesia. BIS is a routinely used monitor that continuously monitors the patient's state of
consciousness during anesthesia. In this way, the depth of anesthesia can be controlled more
precisely (1). When the level of consciousness is deep, the BIS value decreases and increases
as the surface is approached. With this feature, it ensures that the patient's depth of
anesthesia is kept at an optimal level and adjusted when necessary. This may help minimize
anesthesia-related complications(2). BIS alone may not be sufficient to evaluate the depth of
anesthesia. It should be used in conjunction with other clinical findings and monitors.
Nowadays, anesthesia depth monitoring is a widely used method and is performed routinely in
our clinic.
BIS (Bisspectral Index) Suppression Ratio is a value that measures the suppression rate of
brain activity during anesthesia (3). This rate is calculated by analyzing EEG
(Electroencephalogram) signals. This ratio indicates significant decreases in brain activity
and increases as anesthesia deepens (4). Suppression is often desired in cases of deep
anesthesia, especially during surgical intervention. However, an excessively high suppression
rate can lead to delayed recovery times. The use of BIS Suppression Ratio in anesthesia
management can help to more precisely control the patient's arousal process and the depth of
general anesthesia. This value provides the anesthesia team with a guide to optimize the
patient's state of consciousness and minimize complications that may occur during anesthesia.
However, it is important that BIS Suppression Ratio should not be evaluated alone and should
be used in conjunction with other clinical information(5). Each patient's response may be
different, and therefore the anesthesia team must manage the depth of anesthesia by
considering multiple factors. It has been shown in the literature that BIS Suppression Ratio
(SR) values >40 have a similar effect to low BIS values. However, the undesirable Suppression
Ratio in terms of number and duration is not fully known (6).
"Recovery agitation" generally refers to a situation that may occur after a surgical
intervention or anesthesia. This condition describes the restlessness and agitation (symptoms
such as restlessness, tension, insomnia) that the patient shows during the awakening process
and during the recovery period from anesthesia. Recovery agitation sometimes occurs when the
patient tries to wake up. It may occur when it starts and is usually a short-term condition
that resolves on its own. However, in some cases, this agitation may be more pronounced and
disturbing. This may affect the patient's condition and relaxation. The severity of the
agitation may vary from person to person. Rapid recovery from anesthesia in the clinic is
also a risk of agitation. Riker Sedation-Agitation Scale and Richmond Agitation-Sedation
scale are the most frequently used methods to measure recovery agitation (7).
When the literature is examined, there are not enough studies on Bis suppression ratio and
its relationship with recovery agitation is not yet known enough. For this purpose, our study
aimed to question this relationship.