Facial nerve electromyographic monitoring to predict movement in patients titrated to a standard anesthetic depth.

BACKGROUND: Facial nerve (FN) monitoring has been accepted as a standard of care in craniofacial, middle ear, and skull-based surgeries as a means of reducing iatrogenic injury, localizing the FN, and predicting postoperative neurologic function. Past studies have also shown that FN electromyographic monitoring (FNEMG) may have some clinical utility as a monitor of anesthetic depth and predicting patient movement. In this study, we evaluated Bispectral Index (BIS) and FNEMG using two different anesthetic techniques to determine whether these monitors can be used to predict movement in patients undergoing skull-based surgical procedures. METHODS: Using a single-blinded, randomized, controlled clinical trial, the relationship between FNEMG monitoring and BIS to predict movement during specific craniofacial and skull-based surgeries performed under general anesthesia was evaluated. In addition, a total IV anesthetic (TIVA) technique, using propofol and remifentanil, was compared with an inhaled anesthetic technique, using desflurane (DES), to determine which regimen provides the best conditions of adequate anesthesia and prevents movement in nonparalyzed patients undergoing a surgical procedure requiring FNEMG monitoring. RESULTS: The TIVA technique produced better hemodynamic conditions compared with DES. No significant differences were noted in BIS values between the two groups. However, FNEMG activity was lower in the TIVA group during emergence from the effects of anesthesia. More patients moved during anesthesia with DES compared with TIVA, and of the 10 patients who moved, eight had significant FNEMG activity. The positive predictive value of the FNEMG for movement was found to be 38%, and the negative predictive value was 95%. There was no significant change from baseline values in hemodynamics or BIS value for patients who experienced movement compared with those who did not move with FNEMG activity. CONCLUSION: This study shows that FNEMG may be an effective monitor for predicting patient movement when undergoing craniofacial and skull-based surgeries. BIS monitoring, however, was not an adequate monitor to predict movement in this patient population. The DES group had more hemodynamic variability and FNEMG activity, whereas TIVA proved to be a more effective anesthetic in preventing patient movement when clinically titrated to produce stable operation conditions. FNEMG was a useful clinical tool to help predict and prevent movement in these patients.

Patient-controlled analgesia combined with either ondansetron or ondansetron plus prochlorperazine for control of pain and nausea and vomiting in patients undergoing abdominal surgery.

STUDY OBJECTIVE: To compare ondansetron with ondansetron plus prochlorperazine, added to a patient-controlled analgesia (PCA) solution for control of postoperative nausea and vomiting (PONV). DESIGN: Prospective, randomized, double-blinded study. SETTING: University hospital. PATIENTS: 150 ASA physical status I, II, and III patients undergoing abdominal surgery. INTERVENTIONS: Patients were given a PCA morphine solution containing either 30 mg of ondansetron (Group O), 30 mg of ondansetron plus 20 mg of prochlorperazine (Group OP), or no antiemetic (Group C; control group). MEASUREMENTS: Demographic data were recorded, along with anesthetic and surgical time, total fluid intake, frequency of Postanesthesia Care Unit (PACU) PONV, discharge time and length of stay, frequency of PONV while on the hospital floor, highest nausea scores, total PCA morphine use, and PCA utilization times. MAIN RESULTS: Demographic and intraoperative variables were similar in all groups. In the first 24 hours after surgery, nausea was higher in Group C than Group OP. Emesis in Group C was twice that of either Group O or Group OP. No differences were noted between groups in PACU PONV. Patients receiving ondansetron plus prochlorperazine when on the hospital floor had a lower frequency of nausea, while patients receiving ondansetron alone had a lower frequency of vomiting than did the control group. The adjusted odds of vomiting doubled for every 12 hours for Group C patients when receiving PCA. CONCLUSIONS: Combination antiemetics added to PCA reduced emetic symptoms after abdominal surgery.

Morphine/ondansetron PCA for postoperative pain, nausea, and vomiting after skull base surgery.

OBJECTIVE: Patients who underwent skull base procedures have been noted to experience appreciable pain. This study examines pain after surgery and the effectiveness of patient controlled analgesia (PCA) with combination morphine ondansetron for analgesia and control of emesis. STUDY DESIGN AND SETTING: A total of 120 skull base surgery patients were randomized to receive placebo, morphine, or morphine ondansetron. Demographic and intraoperative variables were recorded along with pain, nausea, vomiting, and rescue analgesics. Total PCA use, hospital stay, satisfaction, and cost were also compared. RESULTS: Demographically the groups were similar. Pain was elevated with placebo PCA, and this group averaged twice as many analgesic rescues. Total usage time was lower with placebo PCA. Morphine ondansetron PCA had the lowest pain score with highest satisfaction. Nausea and vomiting was similar but female patients had more vomiting regardless of PCA group. CONCLUSIONS AND SIGNIFICANCE: The use of morphine PCA reduced pain and did not appreciably increase nausea or vomiting. The addition of ondansetron produced no real benefit and its PCA use cannot be justified. EBM RATING: A-1b.