Patient controlled sedation during central neuraxial anesthesia

Use of pre-operative anxiety score to determine the precise dose of butorphanol for intra-operative sedation under regional anesthesia: A double-blinded randomized trial

A randomized double-blinded controlled trial was performed to explore the association between pre-operative anxiety and intra-operative butorphanol requirement to evaluate the precise sedative requirement and to confirm the sedative effect of butorphanol in patients receiving lower-limb orthopedic surgery. The Amsterdam pre-operative anxiety and information scale and the Ramsay sedation score (RSS) were used to assess the patients' pre-operative anxiety score and sedation state during surgery. Patients were divided into two groups according to their pre-operative anxiety score prior to administration of pre-medication. Patients in each group were randomly divided into a butorphanol group and a 0.9% saline group. A total of 142 patients were enrolled and 131 patients were analyzed. The sedation scores of patients with high pre-operative anxiety in the 0.9% saline group were lower than those in the butorphanol group at each time-point after infusion. An increased pre-operative anxiety score predicted an increased duration to reach an RSS of 4 for an acceptable level of sedation (r²=0.887, P<0.0001). In conclusion, butorphanol had a good sedative effect on patients with pre-operative anxiety. The following formula was proposed: Precise dose of butorphanol (µg/kg)=15.26 + (0.14× pre-operative anxiety score), which may provide an improvement for patients exhibiting a high level of pre-operative anxiety. The trial was registered prior to patient enrollment at clinicaltrials.gov on 20.01.2018 (trial registration no. NCT03429179).

Patient-controlled sedation in orthopedic surgery under regional anesthesia: a new approach in procedural sedation

BACKGROUND AND OBJECTIVES

Regional anesthesia is a commonly used technique in orthopedic procedures. Sedation should reduce the patient's anxiety and fear while increasing regional anesthesia quality. This study evaluated the hemodynamic changes, level of sedation, both patients' and surgeons' levels of satisfaction and potential side effects in patient-controlled sedation using propofol.

METHODS

This randomized clinical trial studied sixty ASA physical class I-III patients scheduled for total knee replacement surgery under combined spinal-epidural anesthesia. Patients in Group P (n = 30) received propofol via a patient-controlled analgesia device with the following settings: intravenous propofol bolus dose 400 μg.kg(-1), 5-minute lockout interval and no basal infusion. In Group S, we infused saline 150 using the same settings. To determine the level of sedation, we used BIS and Observer's Assessment of Alertness/ Sedation Scale. For all patients, we recorded the number of requests. As the fi nal evaluation, we scored surgeons' and patients' satisfaction on 4-point scales.

RESULTS

Both BIS values and OAA/S scores were lower in Group P than in Group S. Patients' satisfaction was higher in Group P, although there was no significant difference with respect to surgeons' satisfaction between the groups. The number of requests for sedation was significantly higher in Group S. However, most requests were considered unsuccessful.

CONCLUSION

This study suggests that patient-controlled sedation with propofol can be used efficiently in orthopedic procedures.

Arousal time from sedation during spinal anaesthesia for elective infraumbilical surgeries: Comparison between propofol and midazolam

Background and Aims:

Studies have already compared propofol and midazolam as sedatives during regional anaesthesia. A few studies have focused on recovery characteristics and very few have utilised both instrumental and clinical sedation monitoring for assessing recovery time. This study was designed primarily to compare arousal time from sedation using propofol with that of midazolam during spinal anaesthesia for infraumbilical surgeries, while depth of sedation was monitored continuously with bispectral index (BIS) monitor. The correlation between the BIS score and observer's assessment of awareness/sedation (OAA/S) score during recovery from sedation was also studied.

Methods:

A total of 110 patients were randomly assigned to receive either propofol (Group P, n = 55) or midazolam (Group M, n = 55). Patients in the Group P received bolus of propofol (1 mg/kg), followed by infusion at 3 mg/kg/h; Group M received bolus of midazolam (0.05 mg/kg), followed by infusion at 0.06 mg/kg/h and titration until BIS score 70 was achieved and maintained between 65 and 70. OAA/S score was noted at BIS 70 and again at BIS 90 during recovery. The time to achieve OAA/S score 5 was noted. Spearman's correlation was calculated between the arousal time from sedation and the time taken to reach an OAA/S score of 5 in both the study groups.

Results:

Arousal time from sedation was found lower for Group P compared to Group M (7.54 ± 3.70 vs. 15.54 ± 6.93 min, respectively, P = 0.000). The time taken to reach OAA/S score 5 was also found to be lower for Group P than Group M (6.81 ± 2.54 min vs. 13.51 ± 6.24 min, respectively, P = 0.000).

Conclusion:

A shorter arousal time from sedation during spinal anaesthesia can be achieved using propofol compared with midazolam, while depth of sedation was monitored with BIS monitor and OAA/S score. Both objective and clinical scoring correlate strongly during recovery from sedation.