Spinal Bupivacaine in Ambulatory Surgery

Abstract

The safety of lidocaine spinal anesthesia has recently been called into question by reports of both permanent and transient neurologic toxicity. This study explored the possibility of adapting the longer acting spinal bupivacaine to ambulatory surgery. Sixty patients presenting for ambulatory arthroscopy were randomized to four groups receiving the following spinal anesthetics: Group I (15 mg bupivacaine), 3 mL of 0.5% spinal bupivacaine in 8% dextrose; Group II (10 mg bupivacaine), 2 mL of the 0.5% spinal bupivacaine+1 mL saline; Group III (7.5 mg bupivacaine), 1.5 mL of the 0.5% spinal bupivacaine%1.5 mL saline; Group IV (5 mg bupivacaine), 1 mL of the 0.5% spinal bupivacaine+2 mL saline. Maximum block height was T-5 in Group I versus T-8 in the other groups. Onset times to peak block were similar in all groups and averaged 14 min. Time to two-segment regression, complete regression, micturition, and discharge were significantly reduced from Group I to Group II and from Group II to Group III. Reductions in times between Groups III and IV did not achieve statistical significance. Times from placement of the spinal block until discharge were 471 +/- 35, 260 +/- 15,202 +/- 14, and 181 +/- 8 min, respectively, for the four groups. The intensity of motor block decreased significantly from group to group, such that 13 of the 15 patients in Group IV failed to achieve Bromage level 2 or 3. The intensity of sensory block also decreased from group to group with four patients in Group IV having pain intraoperatively that required further treatment. Therefore, Group III provided the optimum combination of adequate depth of anesthesia and rapid recovery. The results of this study indicate that spinal anesthesia with 7.5 mg of 0.5% bupivacaine in 8% dextrose diluted with an equal volume of saline provides an acceptable spinal anesthetic for ambulatory arthroscopy with a recovery profile appropriate to the ambulatory setting.

Home‐readiness after spinal anaesthesia with small doses of hyperbaric 0.5% bupivacaine

“…A complete motor block (Bromage 3) was achieved in about 50% of the patients in the 2 ml group. This is in accordance with previous studies [6,8]. In spite of the fact that only one patient in the 1 ml group had a complete motor blockade in the lower extremities, the surgeons were satisfied with the block and more intense motor block was not needed.…”

“…In the study by Toft and colleagues, after spinal block with 80 mg of either glucose-free 2% lignocaine or hyperbaric 5% lignocaine, 90% of the 50 patients were able to walk and micturate within 4 h [12]. In our study, only about 40% of patients fulfilled discharge criteria within 4 h. Ben-David and colleagues used different concentrations of hyperbaric bupivacaine in ambulatory surgery [8] and, similar to our study, their patients were able to walk earlier than to void urine. Urinary retention after spinal anaesthesia is caused by parasympathetic block from involvement of the S 2 , S 3 and S 4 spinal segments.…”

“…After the recommendations of de Jong [4] and Sjöström & Bläss [5], we have abandoned the use of hyperbaric 5% lignocaine for spinal anaesthesia until the clinical significance of transient neurological symptoms are resolved. Hyperbaric 0.5% bupivacaine causes reliable spinal block of dosedependent duration [6][7][8]. The use of bupivacaine in spinal anaesthesia is rarely followed by transient neurological symptoms [9].…”

Low‐dose bupivacaine with sufentanil prevents hypotension after spinal anesthesia for hip repair in elderly patients

“…One explanation for the great variability of cephalad spread of sensory block among all patients might be that humans display great variability in cerebrospinal fluid volume (20). This difference (20) probably partly explains the high proportion of inadequate blocks when a reduced dose of local anesthetic is used (11,12,15). The two solutions used in this study had slightly different baricity but both are still hyperbaric compared to cerebrospinal fluid.…”

“…A decreased dose of local anesthetic reduces the severity and incidence of hypotension after spinal block (7,10). However it increases the risk of anesthesia failure in the form of inadequate blocks (11,12).…”