Lower-Dose Mepivacaine Plus Fentanyl May Improve Spinal Anesthesia for Knee Arthroscopy.

ABSTRACT: BACKGROUND:Previous work indicates that 30 mg isobaric mepivacaine 1.5% plus 10 ?g fentanyl produces reliable anesthesia for knee arthroscopy with a more rapid recovery profile than 45 mg mepivacaine. QUESTIONS/PURPOSES:This randomized controlled trial compared plain mepivacaine to three reduced doses of mepivacaine with 10 ?g fentanyl for spinal anesthesia. METHODS:Following written informed consent, subjects undergoing outpatient knee arthroscopy were prospectively randomized into one of four groups: mepivacaine 37.5 mg (M37.5); mepivacaine 30 mg plus fentanyl 10 ?g (M30/F10); mepivacaine 27 mg plus fentanyl 10 ?g (M27/F10); and mepivacaine 24 mg plus fentanyl 10 ?g (M24/F10). The spinal was evaluated by the blinded anesthetist and surgeon. In the post-anesthesia care unit, sensory and motor block resolution was assessed. Subjects rated their satisfaction with the overall experience. RESULTS:Group M30/F10 (n?=?6) had two "fair" anesthetics, and group M27/F10 (n?=?10) had one "fair" and one "inadequate" anesthetic. Both groups were eliminated from further enrollment per study protocol. The recovery profiles showed little difference between groups M37.5 and M30/F10, except for motor block resolution (median (25th percentile, 75th percentile): 171 (135, 195) and 128 (120, 135), respectively). Groups M27/F10 and M24/F10 demonstrated recovery profiles that were faster than group M37.5. Patient satisfaction was 10/10 for all groups. CONCLUSIONS:Adding fentanyl 10 ?g to a lower dose of mepivacaine 1.5% can lead to quicker recovery profiles. However, this advantage of a quicker recovery must be weighed against the likelihood of an incomplete anesthetic.

SUBMITTER: Kahn RL 

PROVIDER: S-EPMC4773686 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature