Basic analgesic use in randomised trials assessing local and regional analgesic interventions for mastectomy: a critical appraisal and clinical implications

Regional analgesia is a core component of an optimal multimodal analgesia technique. Several advanced regional analgesic techniques have been evaluated for mastectomy; however, the optimal choice remains unclear. Many randomised clinical trials (RCTs) evaluating various local/regional analgesic techniques do not include basic analgesics (i.e. paracetamol, non-steroidal anti-inflammatory drugs, cyclooxygenase-2 specific inhibitors, and dexamethasone) which precludes objective evaluation of their efficacy. The aim of this scoping review was to assess the use of basic analgesics in RCTs evaluating efficacy of local and regional analgesic techniques in patients undergoing mastectomy. PubMed was searched to identify relevant articles from January 1, 2010 to May 31, 2023. The key finding of this study is that almost 90% (n=82/92) of the RCTs evaluating local/regional analgesic techniques in patients undergoing mastectomy did not administer well accepted basic analgesics in the comparator groups. Consequently, the conclusions of the RCTs assessing local/regional analgesic techniques for mastectomy should be interpreted with caution. Also, clinical guidelines based on meta-analyses of these RCTs could be inadequate or inappropriate.