Incidence and Risk Factors for Surgical Site Infections Following Oromaxillofacial Oncologic Surgery in Dogs.

Antibiotic stewardship in veterinary medicine is essential to help prevent resistant bacterial infections. Critical evaluation into the benefits of prophylactic use of antibiotics during veterinary surgical procedures is under reported and additional investigation is warranted. The objectives of this paper were to determine the incidence of surgical site infection in dogs that underwent oromaxillofacial oncologic surgery and to identify risk factors for the development of surgical site infection. In this retrospective cohort study including 226 dogs surgically treated for oromaxillofacial tumors between January 1, 1997 and December 31, 2018, the incidence of surgical site infection was determined to be 7.5%. Univariable logistical regression models were used to evaluate potential risk factors for development of surgical site infections including signalment, tumor type, antibiotic protocol, time under anesthesia, location of surgical procedure (dental suite vs. sterile operating room), specific comorbidities, and surgical margins obtained. Anesthetic events lasting greater than 6 h were significantly associated with development of infection. Signalment, comorbidities, administration of anti-inflammatory and immunosuppressive medications, tumor type, histological margin evaluation, surgical procedure location, and antibiotic protocols were not significant contributors to development of infection. Use of antibiotic therapy in this cohort was not protective against development of infection and may not be routinely indicated for all oromaxillofacial oncologic surgeries despite common promotion of its use and the contaminated nature of the oral cavity. Anesthetic time significantly contributed towards the development of infection and use of perioperative antibiotics for surgical procedures lasting >6 h may be routinely warranted.

Impact of the Surgical Environment on the Incidence, Timing, and Severity of Complications Associated With Oromaxillofacial Oncologic Surgery in Dogs.

Numerous reports describe complication rates associated with oromaxillofacial oncologic surgery in dogs, however, investigation regarding the impact of the surgical environment on the incidence of complications is under reported. The objective of this retrospective cohort study, including 226 dogs surgically treated for oromaxillofacial tumors between January 1, 1997 and December 31, 2018, is to evaluate the impact of the surgical environment on the incidence of complications in oromaxillofacial oncologic surgery in dogs. A secondary objective is to report the incidence of local complications in oromaxillofacial oncologic surgery and characterize the type, timing, and severity of complications encountered. Incidence of complications was identified to be 69.9%. No significant association was identified between the incidence, timing, or severity of complications and the training background of the clinician, physical location of the procedure, or the ostectomy instrument used. These results suggest that the surgical environment has little impact on the incidence, timing, and severity of complications in dogs undergoing oromaxillofacial oncologic surgery. The results also emphasize the importance of preparing the surgical team and the client for a high incidence of complications associated with oromaxillofacial oncologic surgery in dogs and indicate that both short-term and long-term follow up is important in these cases. Oromaxillofacial surgery performed by residents-in-training within a veterinary teaching environment with adequate supervision appears to be safe.

Excision of Extensive Orbitozygomaticomaxillary Complex Tumors Combining an Intra- and Extraoral Approach With Transpalpebral Orbital Exenteration.

The junction of the bones of the orbit, caudal maxilla and zygoma intersect to form an anatomically intricate region known as the orbitozygomaticomaxillary complex (OZMC). Given the critical role of the OZMC in the structure, function and esthetics of the skull and midface, tumors in this region present unique challenges to the oromaxillofacial surgeon. Attempts to achieve histologically clean tumor margins in a cosmetically pleasing manner requires excellent intra-operative visualization. Additionally, minimized intra-operative and post-opertive complications is of paramount importance. In this manuscript we describe a combined intra- and extraoral approach to extensive tumors of the OZMC that incorporates orbital exenteration as a technique, which allows for excellent intra-operative visualization and mitigate intra- and post-operative complications. In addition, we describe our experience utilizing the technique in five clinical cases.

A Volumetric Assessment Using Computed Tomography of Canine and First Molar Roots in Dogs of Varying Weight.

Mandibular volume and tooth root volumes were shown to increase at different rates at locations containing the roots of the canine (C) and mesial and distal roots of the first molar (M1). Thirty-six dogs were included in this study. Data were generated using computed tomography at locations of the mandible involving the roots of the C and M1 teeth. Software was used to trace the external surface of the mandible, calculating the volume of the mandible at each location. Similar techniques were used to trace and calculate the volume of the C and M1 roots. Mandible volume, tooth root volume, and root percentage of mandible volume were analyzed and compared using the slopes of the best fit line. At the M1 mesial and distal roots, mandible volume ( P < .001) and root volume ( P < .001) were both noted to increase, with increasing weight at different rates. The rate of change in the root percentage by weight of M1 roots was not different ( P = .214). Each location demonstrated a different increasing rate of change for mandibular volume and increasing root volume. Results show that as patient's weight increases, the mandible and root volumes increase at different rates. Root percentage by volume at all three locations was noted to decrease by the same rate. Canine and M1 roots are proportionally larger than the supporting mandibular bone in smaller patients. Care should be taken to recommend periodontal disease prevention for owners of small dogs and consideration made when performing extractions or other surgery that may destabilize the mandible.