Comparative Efficacy of Opioid-Free and Opioid-Sparing Anesthesia in Dogs Undergoing Dental Procedures: A Prospective Study of Perioperative Analgesia and Hemodynamic Stability

Abstract

This prospective, randomized, and blinded clinical trial aimed to compare opioid-free anesthesia (OFA) and opioid-sparing anesthesia (OSA) protocols for perioperative analgesia and hemodynamic stability in 60 healthy dogs undergoing dental procedures, including extractions and endodontic treatments. All dogs received intramuscular medetomidine (10 µg/kg) as premedication, followed by intraoperative constant rate infusions according to group assignment: OFA1 (ketamine 0.6 mg/kg/hr), OFA2 (ketamine 0.6 mg/kg/hr and lidocaine 1.5 mg/kg/hr), or OSA (ketamine 0.6 mg/kg/hr and hydromorphone 0.05 mg/kg intravenous bolus). Regional nerve blocks using bupivacaine (0.25 mg/kg per site) were administered in all groups. Subcutaneous meloxicam (0.2 mg/kg) was also administered at the end of surgery. Both OFA1 and OFA2 protocols provided effective nociceptive control, with hemodynamic variables remaining within 20% of pre-stimulation values. The incidence of intraoperative rescue analgesia did not differ significantly among groups (p = .35). However, significant overall group differences were observed in mean heart rate (p < .001) and arterial blood pressures (p < .001), with the OSA group demonstrating the lowest values. Postoperative pain scores were not significantly different among groups. Overall, OFA protocols provided effective analgesia and nociceptive control, supporting the clinical feasibility of OFA in dental procedures while highlighting the value of opioids for autonomic modulation.