Abstract
BACKGROUND: There is limited evidence that regional anesthesia reduces pain in patients undergoing mastectomy with immediate implant-based reconstruction. We sought to determine whether regional blocks reduce opioid consumption and improve post-discharge patient-reported pain in this population. METHODS: We retrospectively reviewed patients who underwent bilateral mastectomy with immediate implant-based reconstruction with and without a regional block. We tested for differences in opioid consumption by block receipt using multivariable ordinal regression, and also assessed routinely collected patient-reported outcomes (PROs) for 10 days postoperatively and tested the association between block receipt and moderate or greater pain. RESULTS: Of 754 patients, 89% received a block. Non-block patients had an increase in the odds of requiring a higher quartile of postoperative opioids. Among block patients, the estimated probability of being in the lowest quartile of opioids required was 25%, compared with 15% for non-block patients. Odds of patient-reported moderate or greater pain after discharge was 0.54 times lower in block patients than non-block patients (p = 0.025). Block patients had a 49% risk of moderate or greater pain compared with 64% in non-block patients on postoperative day 5. There was no indication of any reason for these differences other than a causal effect of the block. CONCLUSION: Receipt of a regional block resulted in reduced opioid use and lower risk of self-reported moderate and higher pain after discharge in bilateral mastectomy with immediate implant-based reconstruction patients. Our use of PROs suggests that the analgesic effects of blocks persist after discharge, beyond the expected duration of a 'single shot' block.