Preemptive Versus Postoperative Analgesia in Colorectal Surgery: A Systematic Review and Meta-Analysis

Preemptive and preventative methods have been suggested to decrease pain by blocking nociceptive inputs to tissues. Preemptive analgesia has the potential to enhance postoperative recovery in patients undergoing colorectal surgery. This study aimed to evaluate the efficacy and safety of preemptive versus postoperative analgesia in this population.

We systematically searched PubMed, Scopus, Web of Science, and the Cochrane Library from inception to December 2024, and updated the search in May 2025, to identify randomized controlled trials (RCTs) comparing preemptive analgesia with postoperative analgesia in adult patients undergoing colorectal surgery. The primary outcomes were opioid consumption within 24 h, visual analog scale (VAS) pain score at rest at 24 and 48 h postoperatively. Secondary outcomes included adverse events, length of hospital stay, surgery duration (minutes), and postoperative nausea and vomiting (PONV). The Cochrane Risk of Bias 2.0 tool was used to assess risk of bias, and the strength of evidence was graded using the GRADE approach.

We identified a total of 2739 records. Seven studies involving 625 patients (312 preemptive and 313 postoperative) met the inclusion criteria. Preemptive analgesia decreased VAS scores at 24 h compared to postoperative analgesia (MD -0.45, 95% CI: -0.89 to -0.01, p = 0.04). However, significant heterogeneity was observed among included studies. Additionally, there was no difference between the two groups regarding VAS at 48 h (MD -0.17, 95% CI -0.43 to 0.09, p = 0.21) and opioid consumption at 24 h (MD -21.17, 95% CI 48.18-5.85, p = 0.12).

The findings indicate that preemptive analgesia did not decrease opioid consumption at 24 h; however, it decreased VAS score at 24 h without any difference in VAS at 48 h, length of hospital stay, incidence of PONV, or other adverse events when compared to postoperative analgesia alone in colorectal surgery.

The study is registered in PROSPERO under the registration number CRD420250636020.