Popliteal sciatic nerve block is a commonly used technique for surgery involving the foot and ankle. However,
pain can be difficult to control as the
local anesthetic block wears off. Therefore, we hypothesized that extending the block by using a continuous infusion of
bupivacaine (0.25%) would provide improved
pain management and might facilitate the recovery process after foot or ankle surgery. In this randomized, double-blinded, placebo-controlled study, 24 consenting patients undergoing foot or ankle surgery with a standardized
general anesthetic technique were studied. Before surgery, a popliteal sciatic nerve block was performed in all patients with an 18-gauge Tuohy epidural needle and a peripheral nerve stimulator. After injection of
bupivacaine 0.25% 30 mL and placement of a 20-gauge
catheter, patients were randomly assigned to receive either
0.9% saline (control) or
bupivacaine 0.25% at a constant rate of 5 mL/h for up to 48 h after surgery. An 11-point verbal rating scale (0 = no
pain to 10 = worst
pain imaginable) was used to assess the severity of
pain.
Opioid analgesic use was recorded at specific time intervals after surgery. Follow-up evaluations were performed at 24 h, 48 h, 72 h, and 1 week after surgery to assess
pain scores, as well as patient satisfaction with their
pain management and quality of recovery, by using a 100-point verbal rating scale (1 = highly dissatisfied to 100 = highly satisfied). In the
bupivacaine group, there was a statistically significant reduction in the maximal
pain scores (>50%) and in
opioid use (>60%) during the postoperative period compared with the control group. Patient satisfaction with
postoperative pain management (95 +/- 3 versus 77 +/- 13) and quality of recovery (96 +/- 7 versus 83 +/- 14) was significantly improved in the
bupivacaine group (versus control). In addition, 40% of the patients in the
bupivacaine group (versus none in the control group) were able to be discharged home on the day of surgery (P = 0.087). In conclusion, a continuous infusion of
bupivacaine 0.25% decreased
postoperative pain and the need for
opioid analgesic rescue medication after
orthopedic surgery involving the foot and ankle, leading to improved patient satisfaction and quality of recovery.
IMPLICATIONS: A continuous infusion of
bupivacaine 0.25% (versus saline) at the popliteal fossa by using a simple elastomeric pump is an effective method of decreasing
postoperative pain, reducing the
opioid analgesic requirement, and increasing patient satisfaction with
pain management after
orthopedic surgery involving the foot and ankle. More importantly, the use of the continuous sciatic nerve block in the popliteal fossa facilitated an earlier discharge after lower extremity surgery.