This is an ANSiscope plot of an entire 1-1/2 hour gynecological operation.One can see the balances shooting up upon intubation (which is a highly stressful activity). A bolus of analgesic drug was given at this point. There was not much immediate reaction.
After about 10 minutes, another bolus of analgesic was given. The balance index drops down close to zero, indicating a decrease of sympathetic system activity. The balance is oscillating around zero during the operation and the end of the operation the patient wakes up. One can see the fading away of the anesthetic.
The anesthesiologist did not use the ANSiscope during the surgery. He depended upon his normal instrumentation. One can see that it took close to 10 minutes for him to inject the second dose, The ANSiscope immediately pointed out the problem…he could have injected and saved the patient from more pain.