Transversus Abdominis Plane Block vs. Wound Infiltration for the Reduction of Postoperative Patient-Controlled Analgesia Requirements Following Laparoscopic Hemicolectomy: A Retrospective Case-Control Study

Abstract

Introduction Transversus abdominis plane (TAP) blocks and wound infiltration are commonly used regional analgesic techniques in laparoscopic colorectal surgery. However, their comparative efficacy remains uncertain. This study aimed to evaluate whether TAP blocks reduce postoperative morphine consumption and patient-controlled analgesia (PCA) duration compared to wound infiltration following laparoscopic hemicolectomy. Methods We conducted a retrospective case-control study comparing postoperative opioid requirements and PCA duration in patients who received TAP blocks versus wound infiltration for laparoscopic hemicolectomy. Landmark vs ultrasound-guided TAP block techniques were also compared. The primary outcome was total postoperative morphine consumption via PCA, and the secondary outcome was PCA duration. Data on postoperative adjunct analgesia and patient demographics were also collected. Results Comparing TAP blocks (n=59) and wound infiltration (n=33), no significant difference was found between groups in postoperative morphine consumption via PCA (p=0.111), PCA duration (p=0.092), or average daily morphine requirement via PCA (p=0.452). Comparing ultrasound-guided (n=21) and landmark (n=38) TAP block techniques also yielded no significant difference between groups for each of these dependent variables. Variability in opioid use was high, with large standard deviations observed in all groups. Discussion TAP blocks did not demonstrate a significant opioid-sparing effect compared to wound infiltration following laparoscopic hemicolectomy. These findings contribute to a growing body of literature with conflicting evidence on the efficacy of TAP blocks. However, TAP blocks may offer benefits beyond postoperative opioid-sparing effects. Further prospective studies incorporating postoperative pain scores and recovery metrics are needed to determine their clinical utility in multimodal analgesia protocols for colorectal surgery.

Keywords: laparascopic hemicolectomy; laparoscopy; opioid-sparing analgesia; perioperative analgesia; transversus abdominis plane block (tap block).

Figure 1. CONSORT diagram illustrating the application of exclusion criteria and the sampling ratio of the dataset

CONSORT: Consolidated Standards of Reporting Trials; PCA: patient-controlled analgesia; TAP: transversus abdominis plane

Figure 2. Comparing the effects of the mode of regional analgesia on total postoperative PCA morphine requirement, postoperative PCA duration, and average daily morphine requirement via PCA

There was no effect of mode regional analgesia on (a) the total morphine requirement via PCA, (b) the duration of postoperative PCA requirement, or (c) the average daily postoperative morphine requirement via PCA. Data are presented as mean averages ± 95% confidence intervals. TAP: transversus abdominis plane; PCA: patient-controlled analgesia

Figure 3. Comparing the effects of the TAP block technique on total postoperative PCA morphine requirement, postoperative PCA duration, and average daily morphine requirement via PCA

There was no effect of the TAP block technique on (a) the total morphine requirement via PCA, (b) the duration of postoperative PCA requirement, or (c) the average daily postoperative morphine requirement via PCA. Data are presented as mean averages ± 95% confidence intervals. TAP: transversus abdominis plane; PCA: patient-controlled analgesia; US: ultrasound