Spinal Block with 1.5 mg Hyperbaric Bupivacaine: Not Successful for Everyone

Optimal local anesthetic regimen for saddle block in ambulatory anorectal surgery: an evidence-based systematic review

BACKGROUND

Ambulatory anorectal surgery requires an anesthetic of short duration but profound depth. Saddle block anesthesia (SBA) can provide dense sacral anesthesia with minimal motor blockade, but the ideal local anesthetic agent remains undefined. This systematic review aims to identify the optimal SBA regimen for ambulatory anorectal surgery.

METHODS

We sought randomized trials examining SBA for ambulatory anorectal surgery and stratified patients into four subgroups according to local anesthetic type and dose: (1) longer acting, higher dose; (2) longer acting, lower dose; (3) shorter acting, higher dose; and (4) shorter acting, lower dose. Longer acting agents included bupivacaine and levobupivacaine; shorter acting agents included chloroprocaine, mepivacaine, and prilocaine. Lower dose was defined as ≤5 mg and ≤20 mg for longer and shorter acting local anesthetics, respectively. The primary outcome was time to discharge; secondary outcomes included times to sensory and motor block regression, urine voiding, and ambulation, as well as block success.

RESULTS

A total of 11 trials (1063 patients) were included. Overall study quality and reporting consistency was poor. Doses ranged from 1.5-7.5 mg to 3-30 mg of longer and shorter acting local anesthetics, respectively. Hyperbaric local anesthetics were used in eight trials (953 patients, 86%). The median time to discharge appeared similar across all subgroups with an overall time of 182 (IQR 102) min. The use of long-acting, lower dose regimens was associated with a faster median time to motor block regression. Block success approached 99% among all trials.

CONCLUSIONS

There is presently insufficient qualitative and quantitative evidence to identify an optimal SBA regimen for ambulatory anorectal surgery. Nonetheless, we found that doses as low as 1.5 and 3 mg of longer and shorter acting hyperbaric local anesthetics, respectively, can achieve effective and reliable SBA with timely hospital discharge. Despite similar discharge times, longer acting, lower dose local anesthetics may produce faster motor block regression following SBA for ambulatory anorectal surgery.

Selective spinal anesthesia using 1 mg of bupivacaine with opioid in elderly patients for transurethral resection of prostate

PURPOSE

This study was to evaluate the characteristics of selective spinal anesthesia using 1 mg of bupivacaine combined with fentanyl or sufentanil in elderly patients undergoing transurethral resection of prostate.

MATERIALS AND METHODS

Fifty-six patients were randomized into two groups. The Fentanyl group received 0.5% hyperbaric bupivacaine 0.2 mL+fentanyl 20 μg+5% dextrose 1.4 mL, and the Sufentanil group received 0.5% hyperbaric bupivacaine 0.2 mL+sufentanil 5 μg+5% dextrose 1.7 mL intrathecally. Intraoperative and postoperative characteristics were evaluated. Patient satisfaction was assessed postoperatively.

RESULTS

Twenty-six patients in each group completed the study. The median peak sensory block level was similar between two groups, but sensory regression time was longer in the Sufentanil group than the Fentanyl group (p=0.017). All patients were able to move themselves to the bed without any aid when they arrived at the admission room. Pain scores were lower in the Sufentanil group than the Fentanyl group at postoperative 6, 12, and 18 hours (p=0.001). Compared to the Fentanyl group, the Sufentanil group required less postoperative analgesia (p=0.023) and the time to the first analgesic request was longer (p=0.025). Twenty-four of 26 patients (92.3%) in each group showed "good" satisfaction level.

CONCLUSION

Selective spinal anesthesia using 1 mg of bupivacaine with fentanyl or sufentanil provided appropriate sensory block level with spared motor function for transurethral resection of the prostate in elderly patients. Intrathecal sufentanil was superior to fentanyl in postoperative analgesic quality.