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Background and Aims We retrospectively evaluated the clinical analgesia efficacy in multimodal analgesic techniques combining a single peripheral nerve block and a single acetaminophen administration.

Methods A retrospective observational study approved by an ethics committee at a single-center university hospital, 273 lower extremity surgeries performed between April 2020, and April 2021, were conducted. Subjects were maintained by general anesthesia with several US-guided nerve blocks. Pain score (VAS value ≥five) within 2 hours was defined as block failure (F group: 12.1%). 240 patients in the successful nerve block group (group S) were classified into acetaminophen non-treated group (group A) and acetaminophen treated group (group B) to evaluate their clinical efficacy. The primary endpoints were VAS at 0, 2, 6, 12, and 24 hours, the number of patients with VAS values ≥ five within 6 and 24 hours, rescue medications, PONV cases. Statistical analysis using the χ-square , T and Mann-Whitney U test and p-value<0.05 was considered statistically significant.

Results No background difference between Group A and B. Acetaminophen-related postoperative pain in 6 hours (7 patients (11.3%) in Group A and 7 patients (3.9%) in Group B; P=0.03). No differences were noted in rescue medications, or PONV counts between A and B. Block failure related to higher VAS through the postoperative course and rescue medications.

Conclusions A lower VAS score within 2 hours postoperatively was associated with lower VAS values up to 24 hours and a lower number of rescue medications. A single intraoperative acetaminophen regimen with nerve block associated with lower VAS values in 6 hours postoperatively.

Attachment ADD chart ESRA 2023 paris.pdf