The effectiveness of ambulatory continuous popliteal sciatic nerve blockade on patient-reported overall benefit of analgesia in patients undergoing foot or ankle surgery (CAREFREE trial); a randomized, open label, non-inferiority trial.

STUDY OBJECTIVE

Management of pain after foot and ankle surgery remains a concern for patients and healthcare professionals. This study determined the effectiveness of ambulatory continuous popliteal sciatic nerve blockade, compared to standard of care, on overall benefit of analgesia score (OBAS) in patients undergoing foot or ankle surgery. We hypothesized that usage of ambulatory continuous popliteal sciatic nerve blockade is non-inferior to standard of care.

DESIGN

Single center, randomized, non-inferiority trial.

SETTING

Tertiary hospital in the Netherlands.

PATIENTS

Patients were enrolled if ≥18 years and scheduled for elective inpatient foot or ankle surgery.

INTERVENTION

Patients were randomized to ambulatory continuous popliteal sciatic nerve blockade or standard of care.

MEASUREMENTS

The primary outcome was the difference in OBAS, which includes pain, side effects of analgesics, and patient satisfaction, measured daily from the first to the third day after surgery. A non-inferiority margin of 2 was set as the upper limit for the 90% confidence interval of the difference in OBAS score. Mixed-effects modeling was employed to analyze differences in OBAS scores over time. Secondary outcome was the difference in opioid consumption.

MAIN RESULTS

Patients were randomized to standard of care (n = 22), or ambulatory continuous popliteal sciatic nerve blockade (n = 22). Analyzing the first three postoperative days, the OBAS was significantly lower over time in the ambulatory continuous popliteal sciatic nerve blockade group compared to standard of care, demonstrating non-inferiority (-1.9 points, 90% CI -3.1 to -0.7). During the first five postoperative days, patients with ambulatory continuous popliteal sciatic nerve blockade consumed significantly fewer opioids over time compared to standard of care (-8.7 oral morphine milligram equivalents; 95% CI -16.1 to -1.4).

CONCLUSIONS

Ambulatory continuous popliteal sciatic nerve blockade is non-inferior to standard of care with single shot popliteal sciatic nerve blockade on patient-reported overall benefit of analgesia.