Analgesic efficacy of diclofenac in combination with morphine and paracetamol after mastectomy and immediate breast reconstruction

Background:  Breast cancer treatment with mastectomy and immediate breast reconstruction (IBR) is associated with intense pain in the primary post-operative period. The present prospective, placebo-controlled and double-blind study aimed to evaluate the analgesic efficacy of diclofenac, a non-steroid anti-inflammatory drug (NSAID), in combination with paracetamol and opioids. This was done by 64-h assessment of post-operative pain intensity, opioid consumption, blood loss, nausea and tiredness.

Methods:  Fifty women selected for mastectomy and IBR with submuscular implants with or without axillary lymph node dissection (ALND) were randomized to receive diclofenac 50 mg × 3 or placebo rectally in addition to oral paracetamol and intravenous opioids delivered using a patient-controlled analgesia (PCA) technique.

Results:  During the first 20 h post-surgery, patients who received diclofenac experienced significantly less pain when resting than those who received placebo. When moving, a non-significant estimated difference in pain in favour of diclofenac was also noted. Opioid consumption during the first 6 h post-operatively was 34% less with diclofenac than with placebo. Means (SD) were 16.9 (10.3) mg and 25.6 (10.2) mg, respectively (P = 0.007). After 64 h, the difference was no longer statistically significant. Post-operative bleeding was significantly higher with diclofenac than with placebo (P < 0.01). Nausea and tiredness did not differ between the groups.

Conclusions:  The addition of NSAID to paracetamol and opioid-PCA reduced opioid consumption and improved pain relief during the first 20 h at rest but was not convincingly effective during mobilization. Post-operative blood loss was higher with diclofenac.