The efficacy of continuous bupivacaine infiltration following arthroscopic rotator cuff repair

This prospective, randomized, double-blind study with a placebo group and 2 experimental groups evaluated the efficacy of continuous low-dose bupivacaine infiltration by infusion pump after arthroscopic rotator cuff repair.

Sixty patients undergoing arthroscopic rotator cuff repair received a bolus injection in the subacromial space of 35 mL of 0.25% bupivacaine with 1:200,000 epinephrine at surgical closure and were randomized to 1 of 3 groups: 0.25% bupivacaine at 2 mL/hr (n = 20), 0.25% bupivacaine at 5 mL/hr (n = 20), or saline at 5 mL/hr (n = 20) via infusion pump into the subacromial space. Pain was evaluated using the visual analog scale (VAS) and narcotic consumption was measured until 48 hours after surgery and converted to dose equivalents (DE).

Sixty patients used the infusion pump for a mean of 43.9 hours (range, 15.50 to 50.75 hrs). Mean total narcotic consumption, expressed in DEs, was 2.24 for the 2-mL group, 3.52 for the 5-mL group, and 2.32 for the placebo group. Mean pain score was 2.9 for the 2-mL group, 3.6 for the 5-mL group, and 3.3 for the placebo group. There were no differences in operating room time or infusion pump use time among groups. The 2-mL group had a nonsignificant trend toward less pain and lower narcotic consumption. The 5-mL group evidenced a nonsignificant trend toward more pain and higher narcotic consumption.

This study neither supports nor refutes the use of infusion pumps. We hypothesized that the placebo group would experience greater pain than the 5-mL group; however, a nonsignificant trend toward the contrary occurred. A trend toward less pain in the 2-mL group was not significant.

Level II, randomized controlled trial of therapeutic treatment that lacks statistical significance and narrow confidence intervals.