Comparison of incisional, transverse abdominis plane, and rectus sheath blocks in dogs undergoing ovariohysterectomy.

Abstract

To compare the analgesia provided by incisional (Incisional), transverse abdominis plane (TAP), and rectus sheath (RS) blocks in dogs submitted for ovariohysterectomy (OHE). 22 female mixed-breed dogs were allocated into 3 treatments of Incisional (n = 7), TAP (n = 7), and RS (n = 8) and underwent OHE from April 4 to December 6, 2022. After premedication with acepromazine (0.05 mg/kg) and morphine (0.5 mg/kg), anesthesia was induced (6 mg/kg) and maintained (0.4 mg/kg/min) with propofol. Each dog randomly received either an incisional (blind technique), TAP, or RS (ultrasound-guided) block. Intraoperative analgesia was assessed using cardiorespiratory variables. Postoperative analgesia was evaluated up to 6 hours after the operation with a Short Form of Glasgow Pain Scale (SF-GCPS) and Visual Analog Scale (VAS). Fentanyl was administered as a rescue analgesic when needed. During surgery, all data remained within normal limits without any significant differences. Fentanyl was administered to 1 dog in the Incisional and 1 in the TAP. Post-operatively, a single dose of fentanyl was given to 1 dog in the TAP and 1 in the RS. Four dogs in the Incisional and 3 in the RS received both doses of fentanyl. There was no significant difference regarding postoperative rescue analgesia among treatments. All 3 techniques demonstrated acceptable intra- and post-operative analgesia efficacy in dogs undergoing OHE. Further studies are warranted to confirm these findings.