A randomized, double-blind, placebo-controlled trial of preemptive analgesia with bupivacaine in patients undergoing mastectomy for carcinoma of the breast

Abstract

Background: In this prospective, randomized, placebo-controlled, double-blinded clinical trial we tested the hypothesis that preemptive analgesia with bupivacaine applied in the area of the surgical incision in patients undergoing mastectomy for breast cancer would reduce post-operative acute pain and would reduce the amount of analgesics used during surgery and in the post-operative period.

Material/methods: Participants were assigned into 1 of 2 groups--with bupivacaine applied in the area of surgical incision or with placebo. We assessed the intraoperative consumption of fentanyl, the postoperative consumption of morphine delivered using a PCA method, and the subjective pain intensity according to VAS score reported by patients in the early post-operative period.

Results: Out of 121 consecutive cases qualified for mastectomy, 112 women were allocated randomly to 1 of 2 groups--group A (bupivacaine) and group B (placebo). The final study group comprised 106 breast cancer cases. Between the groups, a statistically significant difference was observed with respect to: lower fentanyl consumption during surgery (p = 0.011), lower morphine (delivered by means of a PCA) consumption between the 4-12th postoperative hours (p = 0.02) and significantly lower pain intensity assessed according to VAS score at the 4th and 12th hours after surgery (p = 0.004 and p = 0.02 respectively) for the group A patients.

Conclusions: Preemptive analgesia application in the form of infiltration of the area of planned surgical incisions with bupivacaine in breast cancer patients undergoing mastectomy decreases post-operative pain sensation, limits the amount of fentanyl used during surgery, and reduces the demand for opiates in the hours soon after surgery.

Figure 1

Trial algorithm. US – Ultrasound Imaging; MM – Mammography; po. – per os; iv. – intravenous; bw. – body weight; VAS – Visual Analogue Scale; PCA – Patient Controlled Analgesia; hrs – hours.

Figure 2

CONSORT diagram showing flow of participants through the trial.

Figure 3

Diagram of mean VAS score in postooperative period in patients in group A (bupivacaine) and group B (placebo).