Botulinum toxin type A as an adjunct in postoperative pain management in dogs undergoing radical mastectomy

Abstract

The aim of this randomised placebo-controlled, observer-blinded study was to evaluate the analgesic effects of botulinum toxin type A (BoNT-A) as an adjunct for postoperative pain control in dogs. Sixteen dogs undergoing bilateral radical mastectomy for treatment of mammary tumours were enrolled. Twenty-four hours before surgery, the subjects were distributed into two groups of eight dogs each: 7 iu/kg BoNT-A (BoNT-A) or saline (Control) was administered subcutaneously in each mammary gland. Following sedation with intramuscular 0.03 mg/kg acepromazine and 0.3 mg/kg morphine, anaesthesia was induced intravenously with 4 mg/kg propofol and maintained with isoflurane/O2. Postoperative analgesia was evaluated for 72 hours after extubation using the Visual Analogue Scale (VAS) and modified Glasgow Composite Measure Pain Scale (modified-GCMPS). Rescue analgesia was provided with intramuscular morphine (0.5 mg/kg). Data were analysed using analysis of variance, Tukey's test, Mann-Whitney U test and Friedman test (P<0.05). The pain scores were significantly lower in the BoNT-A than in the Control from 8 hours to 60 hours and from 12 hours to 60 hours after extubation, based on the VAS and modified-GCMPS, respectively. Rescue analgesia was required by significantly more dogs in the Control (7/8) compared with the BoNT-A (2/8) (P=0.022). Pre-emptive BoNT-A appears to be effective as an adjuvant for postoperative pain management in dogs undergoing bilateral radical mastectomy.

Intraoperative abobotulinumtoxinA alleviates pain after surgery and improves general wellness in a translational animal model

“…For example, in rats, intraplantar or intrathecal injection of onaBoNT-A significantly reduced the cumulative post-surgical pain score–a measure of non-evoked pain based on the position of the operated paw in relation to the cage floor 22 . Also, aboBoNT-A reduced non-evoked postoperative pain and need for rescue analgesia in dogs undergoing radical bilateral mastectomy 23 . Overall, the analgesic efficacy of aboBoNT-A in the post-surgical pain pig model is well aligned with few examples of its use in the clinic.…”

Paravertebral Block Plus Thoracic Wall Block versus Paravertebral Block Alone for Analgesia of Modified Radical Mastectomy: A Retrospective Cohort Study

“…Aiyama (1973) [30] reported that through communications with the intercostobrachial nerve, the MPN may contain sensory fibers distributed to ventral surfaces of the arm, thoracic wall near the axilla, and inferolateral part of the pectoralis major. A few studies have reported pectoralis muscle spasm as a source of chest wall pain after tissue expander reconstruction [31] and radical mastectomy [32]. Studies have described a pectoral nerve block for use in patients undergoing subpectoral breast augmentation [10,23,33].…”

Therapeutic Applications of Botulinum Neurotoxins in Veterinary Medicine

“…Other than for osteoarthritic pain, the analgesic effect of BoNT-A (Dysport) was tested in post-operative bilateral radical canine mastectomy and showed usefulness as an adjuvant antinociceptive agent to control pain, effective when injected prior to surgery [ 62 ]. By inhibiting the release of neuropeptides at the nociceptive nerve endings, BoNT-A lowers directly peripheral, and indirectly central sensitivity, providing analgesia.…”