Benefit of regional anaesthesia on postoperative pain following mastectomy: the influence of catastrophising

Abstract

Background: Previous studies suggest that truncal regional anaesthesia (TRA), including techniques such as paravertebral block, may contribute significantly to analgesia after mastectomy. However, the severity and impact of postoperative pain varies markedly amongst individuals, making the identification of patients who would benefit most from TRA a potentially important step toward personalised perioperative care.

Methods: In this prospective observational study, mastectomy patients (n=122) were recruited and systematically assessed for psychosocial characteristics including pain catastrophising before surgery, and either received preoperative TRA (n=57) or no block (n=65).

Results: Age, baseline pain, and psychosocial traits did not differ between these groups. TRA was associated with lower overall pain scores and opioid consumption perioperatively, with a larger proportion of patients without block (50% vs 28%) reporting moderate-severe pain (more than three/10) on the day of surgery. Mixed model analysis of variance revealed a significant interaction between catastrophising and TRA, such that amongst patients with high baseline catastrophising, TRA was associated with substantially lower pain severity score (58% lower), while amongst patients with low baseline catastrophising, TRA was associated with only 18% lower pain severity. At 2 weeks, this interaction between baseline catastrophising and TRA was also observed when examining surgical pain burden, with higher baseline catastrophising patients who had received TRA reporting lower pain and less frequent opioid use (40% vs 70% of patients).

Conclusions: TRA provided immediate analgesic benefit for patients undergoing mastectomy on the day of surgery, but this effect appeared more pronounced and sustained amongst patients with higher baseline catastrophising.

Clinical trial registration: NCT02329574.

Keywords: catastrophising; mastectomy; paravertebral block; postsurgical pain; regional anaesthesia.

Fig 1

Patients enrolled and data included in analysis. POD, postoperative day; TRA, truncal regional anaesthesia.

Fig 2

Effect of truncal regional anaesthesia on perioperative pain and opioid administration. (a) Overall pain score at rest and with movement in patients with and without truncal regional anaesthesia on postoperative day 0 (POD0) and (b) total perioperative opioid consumption (pre-, intra-, and postoperative in the recovery room) in patients with and without truncal regional anaesthesia. TRA, truncal regional anaesthesia.

Fig 3

Effect of truncal regional anaesthesia on perioperative pain and opioid administration in patients with high and low baseline catastrophising. (a) Pain on postoperative day 0 (POD0) and (b) total perioperative opioid consumption in patients who reported high (pain catastrophising scale [PCS] >10) and low (PCS≤10) catastrophising at baseline, with and without truncal regional anaesthesia. catas, catastrophising; TRA, truncal regional anaesthesia.

Fig 4

Effect of truncal regional anaesthesia on pain burden and PRN opioid use at 2 weeks in patients with high and low baseline catastrophising. (a) Pain burden index scores and (b) opioid use at 2 weeks amongst high and low catastrophisers who did or did not receive truncal regional anaesthesia. catas, catastrophising; TRA, truncal regional anaesthesia.