The high frequency variability index (HFVI) has recently gained attention for its potential role in managing general anesthesia. HFVI monitoring quantifies high frequency components as a measure of parasympathetic nervous system activity. This approach enables the non-invasive and continuous monitoring of patient stress, including acute pain, during anesthesia. One notable advantage of HFVI monitoring is its potential to prevent intraoperative opioid overdose. We used HFVI monitoring during the anesthetic management of a 30-year-old woman with a history of delayed awakening from previously administered general anesthetics. She had previously undergone a mandibular distraction osteogenesis procedure in 2019 followed by a maxillary osteotomy in 2022. Both of these procedures were performed under total intravenous anesthesia with propofol ; afterwards, the patient experienced prolonged arousal times of 29 and 39 minutes, respectively, from the end of surgery until extubation. The delayed awakening was thought to have been associated with the use of opioids (fentanyl, remifentanil) or the intravenous anesthetic (propofol). To reduce the likelihood of delayed awakening, propofol was avoided during the presently reported treatment and opioid dosing was adjusted using HFVI monitoring. This approach resulted in successful anesthetic management without delayed awakening. HFVI monitoring may be valuable as an indicator of pain management during anesthesia.
