Levobupivacaine vs racemic bupivacaine in spinal anesthesia for sequential bilateral total knee arthroplasty: a retrospective cohort study

• Increased local anesthetic dose prolongs spinal anesthesia duration.
• Only low dose of local anesthetic for spinal anesthesia has been evaluated.
• Higher dosages of levobupivacaine and hyperbaric bupivacaine were compared.
• Levobupivacaine has a higher spinal anesthesia efficacy and a better safety profile.

Study objectivesTo compare the anesthetic potency and safety of spinal anesthesia with higher dosages of levobupivacaine and bupivacaine in patients for bilateral sequential for total knee arthroplasty (TKA).DesignRetrospective cohort study.SettingOperation theater with postoperative inpatient follow-up.PatientsThe medical records of 315 patients who underwent sequential bilateral TKA were reviewed.InterventionsPatients who received intrathecal levobupicavaine 0.5% were compared with patients who received hyperbaric bupivacaine 0.5% with fentanyl 25 μg for spinal anesthesia.MeasurementsThe primary outcome was the use of rescue analgesia (systemic opioids, conversion to general anesthesia) during surgery for both groups. Secondary outcomes included adverse effects of local anesthetics (hypotension and bradycardia) during surgery and morbidity related to spinal anesthesia (postoperative nausea, vomiting, and bleeding) during hospital stay.Main resultsOne hundred fifty patients who received intrathecal levobupivacaine 0.5% (group L) were compared with 90 patients given hyperbaric bupivacaine 0.5% with fentanyl 25 μg (group B). The mean volume of levobupivacaine administered was 5.8 mL (range, 5.0-6.0 mL), and that of bupivacaine was 3.8 mL (range, 3.5-4.0 mL). Both groups achieved similar maximal sensory level of block (T6). The time to maximal height of sensory block was significantly shorter in group B than group L, 18.2 ± 4.5 vs 23.9 ± 3.8 minutes (P< .001). The time to motor block of Bromage 3 was also shorter in group B (8.7 ± 4.1 minutes) than group L (16.0 ± 4.5 minutes) (P< .001). Patients in group B required more anesthetic supplement than group L (P< .001). Hypotension and postoperative bleeding were significantly less common in group L than group B.ConclusionLevobupivacaine at a higher dosage provided longer duration of spinal anesthesia with better safety profile in sequential bilateral TKA.