Comparative analysis of analgesic efficacy and functional recovery in open pancreaticoduodenectomy: a randomized controlled trial of local anesthetic wound infiltration, transversus abdominis plane block, and intramuscular electrical stimulation.

Background: Pancreaticoduodenectomy (PD) is associated with severe postoperative pain. Optimized pain management can potentially elevate patients' postoperative quality of life. This study focused on comparing the analgesic efficacy and subsequent functional recovery of three techniques, continuous local wound infiltration (LWI), four-quadrant transversus abdominis plane (4QTAP) block, and needle electrical twitch obtaining intramuscular stimulation (NETOIMS), in patients subjected to open PD.

Methods: This is a prospective, single-blinded, randomized controlled study. Among a total of 80 eligible patients, 72 were randomized into the LWI, 4QTAP block, or NETOIMS groups for postoperative pain management. The primary outcome measured was the pain score, which was recorded on postoperative days (PODs) 0, 1, 2, 3, 5, 7, 14, and 28. Additionally, consumption of morphine milligram equivalents (MMEs) and ibuprofen until POD 3 was analyzed. Functional recovery indicators, such as gait speed and peak cough flow (PCF), were assessed on the day before surgery (baseline), and on PODs 2, 7, 14, and 28. A one-way analysis of variance, with subsequent Bonferroni analysis, was used to compare these main outcomes.

Results: Out of the 72 patients, 68 (LWI, 22; 4QTAP, 23; NETOIMS 23) were included in the final analysis. Compared to the LWI group, both the 4QTAP block and NETOIMS group demonstrated significantly lower pain scores from PODs 0 through 7 (P<0.001 for POD 0-5; P=0.001 for POD 7, for both groups). The pain scores in the 4QTAP block and NETOIMS groups were comparable across all recorded time points. Up to POD 3, there was a significant reduction in both MMEs (P<0.001) and ibuprofen consumption (P=0.003) in these groups. Additionally, on POD 2, the 4QTAP block and NETOIMS groups exhibited superior PCF (P<0.001) and faster gait speed (P=0.008) compared to the LWI group.

Conclusions: Compared to LWI, both 4QTAP block and NETOIMS were more effective in reducing postoperative pain, necessitated fewer analgesics, and facilitated improved functional recovery after PD.

Trial Registration: Clinical Research Information Service of Korea Disease Control and Prevention Agency; cris.nih.go.kr; registration ID: KCT0005814.