Postoperative complications following TECA-LBO in the dog and cat.

The medical records for 133 total ear canal ablations combined with lateral bulla osteotomies (TECA-LBOs) performed on 82 dogs (121 ears) and 11 cats (12 ears) between 2004 and 2010 were reviewed to determine if the duration of preoperative clinical signs was associated with the incidence of postoperative facial nerve injury and Horner's syndrome. Other perioperative complications, such as a head tilt, nystagmus, incisional drainage, draining tracts, hearing loss, as well as bacterial culture results, were noted. Postoperative facial nerve paresis occurred in 36 of 133 ears (27.1%), and paralysis occurred in 29 of 133 ears (21.8%), with no significant difference between species. Thus, postoperative facial nerve deficits occurred in 48.9% of ears. The median duration of clinically evident temporary facial nerve deficits was 2 wk for dogs and 4 wk for cats. Dogs had a significantly longer duration of preoperative clinical signs and were less likely than cats to have a mass in the ear canal. Dogs were less likely to have residual (> 1 yr) postoperative facial nerve deficits. The incidence of postoperative Horner's syndrome was significantly higher in cats than dogs. The duration of preoperative clinical signs of ear disease was not associated with postoperative facial nerve deficits.

Acquired bilateral laryngeal paralysis associated with systemic lupus erythematosus in a dog.

A 4 yr old spayed female Labrador retriever was referred for acute respiratory distress and was found to have bilateral laryngeal paralysis. Physical examination and biochemical testing were consistent with systemic lupus erythematosus (SLE) and did not reveal a likely alternative cause for the laryngeal paralysis. Following immunosuppressive and supportive treatment, the dog regained normal laryngeal function. At a scheduled follow-up examination 6 wk later, normal laryngeal function was confirmed via sedated laryngeal examination. Laryngeal paralysis associated with SLE has been reported in humans, but this is the first known report of acquired laryngeal paralysis associated with SLE in the dog.

Chronic hernia repair in a rat model using small intestinal submucosa.

BACKGROUND. Small intestinal submucosa (SIS) body wall defect repair in preclinical studies results in host tissue that resembles original host tissue histologically and has adequate strength to maintain repair integrity. However, these studies have been performed using acute hernia models that may not represent healing in a naturally occurring hernia. METHODS. Fifty-four male Sprague-Dawley rats were divided into nine groups (n = 6) and fascia/muscle/peritoneal abdominal wall defects were created. One control group had no surgery. Four surgery groups had defects repaired immediately by (1) fascia suture apposition, (2) polypropylene mesh (PPM) peritoneal onlay, (3) SIS inlay, or (4) SIS peritoneal onlay. After defect creation, chronic hernias matured for 28 days, and then were similarly repaired. Follow-up after hernia repair for all groups was 28 days. Gross evaluation for hernia recurrence, infection, and adhesions was followed by histopathology and tensile testing of the repair. RESULTS. There were no recurrent hernias or infection. Adhesions covered all implants. Histopathologic findings of inflammation and fibrosis were similar between all groups. There were no significant differences in tensile strength between SIS and PPM healing/incorporation or between acute and chronic hernia groups. Normal body wall was stronger than all repairs. Fascia closure in chronic hernias was stronger than acute fascia closure (p < .01). CONCLUSIONS. We found no significant differences between SIS and PPM healing/incorporation as determined by gross and histopathology and tensile strength testing. The study suggests that preclinical testing of abdominal body wall reconstruction in the rat may be adequately performed in acute studies.

Association between chronic azotemic kidney disease and the severity of periodontal disease in dogs.

Naturally occurring periodontal disease affects >75% of dogs and has been associated with cardiac lesions and presumptive endocarditis. However, the relationships between periodontal disease and chronic kidney disease (CKD) in dogs have not been studied. In a retrospective longitudinal study the incidence of azotemic CKD was compared between a cohort of 164,706 dogs with periodontal disease and a cohort of age-matched dogs with no periodontal disease from a national primary care practice. These dogs contributed 415,971 dog-years of follow-up from 2002 to 2008. Hazard ratios and 95% confidence intervals from Cox regression were used to compare the incidence of azotemic CKD in dogs with stage 1, 2, or 3/4 periodontal disease to dogs with no periodontal disease. The hazard ratio for azotemic CKD increased with increasing severity of periodontal disease (stage 1 hazard ratio=1.8, 95% confidence interval: 1.6, 2.1; stage 2 hazard ratio=2.0, 95% confidence interval: 1.7, 2.3; stage 3/4 hazard ratio=2.7, 95% confidence interval: 2.3, 3.0; P(trend)=<0.0001) after adjustment for age, gender, neuter status, breed, body weight, number of hospital visits, and dental procedures. Increasing severity of periodontal disease was also associated with serum creatinine >1.4 mg/dl and blood urea nitrogen >36 mg/dl, independent of a veterinarian's clinical diagnosis of CKD.

Analgesic effect of bupivacaine eluting porcine small intestinal submucosa (SIS) in ferrets undergoing acute abdominal hernia defect surgery.

BACKGROUND: Porcine small intestinal submucosa (SIS) is used as a biological implant for abdominal wall hernia repair to facilitate wound healing and augment local tissue strength. This prospective, randomized, blinded study evaluated local pain control provided by bupivacaine adsorbed to SIS for repair of acutely created abdominal wall full thickness muscle/fascial defects in ferrets. MATERIALS AND METHODS: Eighteen healthy ferrets were randomly and equally assigned to three groups: (1) SIS with bupivacaine subjected to surgery, (2) SIS with no bupivacaine subjected to surgery, and (3) anesthesia only control group. Ferrets in groups 1 and 2 were anesthetized with butorphanol and sevoflurane for the surgery. Control ferrets were anesthetized in the same fashion for the same duration without surgery. Behavior and pain were evaluated in all ferrets by behavioral observation, algometer, and palpometer measurements, and heart and respiratory rates each obtained before surgery and at various intervals for 96 h after surgery. When pain reached a predetermined threshold, buprenorphine was used as a rescue analgesic. The serum and combined tissue concentrations of bupivacaine were analyzed. RESULTS: Overall, the palpometer testing was better tolerated in the bupivacaine treated SIS group than by the untreated SIS group (P = 0.04). There was an observed physiologically significant difference in algometer and other palpometer readings as well as heart and respiratory rates. All ferrets in the untreated SIS group were rescued while 33% of the SIS-bupivacaine groups were rescued (P < 0.01). Peak serum concentrations of bupivacaine were in the range of 0.7 µg/mL with tissue level below detection levels and no clinical signs of toxicity were observed. CONCLUSIONS: Bupivacaine adsorbed to SIS provided some degree of pain relief over 2-4 days with no clinical adverse effects observed in the ferrets.

Evaluation of unilateral arytenoid lateralization for the treatment of laryngeal paralysis in 14 cats.

Laryngeal paralysis is a relatively common cause of upper airway obstruction in middle-aged to older, large-breed dogs; however, it is rare in the cat. The purpose of this study is to describe a series of cats diagnosed with laryngeal paralysis treated by unilateral arytenoid lateralization. Fourteen cats met the criteria of the study. Intraoperative and postoperative complications were seen in 21% (three of 14) and 50% (seven of 14) of cases, respectively. Median duration of follow-up was 11 months (range 3 weeks to 8 years). None of these cats had recurrence of clinical signs. Based on this brief case series, unilateral arytenoid lateralization appeared to be a suitable method for treating laryngeal paralysis in cats. Additional studies are warranted to determine the type and frequency of long-term complications.

Tensile strength comparison of small intestinal submucosa body wall repair.

BACKGROUND: Porcine small intestinal submucosa (SIS) has been studied for body wall repair. However, the best method to implant the biological material has not been investigated. The objective of this study was to compare tensile strengths achieved after healing when SIS was placed using three implant techniques (onlay, inlay, underlay) in a porcine model of abdominal wall defect. MATERIALS AND METHODS: Twenty female domestic pigs had three abdominal midline sites assigned to one of five test groups: SIS implantation using inlay, onlay, or underlay technique; sham surgery (sutured midline incision) or normal body-wall control. Full-thickness muscle/fascia midline abdominal defects (6 x 4 cm) were surgically created and then repaired using eight-layer SIS. Healing was evaluated at 1 and 4 post-operative months by tensile strength testing and histopathology. RESULTS: Hernias were not observed. Tensile strengths were not statistically different between the five test groups (P = 0.39) or between months 1 and 4 (P = 0.35). The caudal site was stronger than the cranial or middle sites in the 1 month group (P < 0.0001). Histologically, healing appeared to progress over time as the repair site showed remodeling towards an interlacing fibrous connective tissue pattern. CONCLUSIONS: No significant differences in tensile strength were found between implant techniques and were not statistically different from sham surgery and normal control tissue. This study suggested that SIS healing/remodeling provides sufficient tensile strength for the repair of ventral (anterior) abdominal wall defects when implanted using any of three common techniques.

Morphologic study of three collagen materials for body wall repair.

BACKGROUND: The search for ideal prostheses for body wall repair continues. Synthetic materials such as polypropylene mesh (PPM) are associated with healing complications. A porcine-derived collagen-based material (CBM), small intestinal submucosa (SIS), has been studied for body wall repair. Renal capsule matrix (RCM) and urinary bladder submucosa (UBS) are CBMs not previously evaluated in this application. This is the first implant study using RCM. MATERIALS AND METHODS: Full-thickness muscle/fascia ventral abdominal wall defects were repaired with SIS, RCM, UBS, and PPM in rats with omentum and omentectomy. A random complete block design was used to allot implant type to each of 96 rats. Healing was evaluated at 4 and 8 weeks. Adhesion tenacity and surface area were scored. Implant site dimensions were measured at implantation and necropsy. Inflammation, vascularization, and fibrosis were histopathologically scored. Data were compared by analysis of variance (P < 0.05). RESULTS: PPM produced a granulomatous foreign body response in contrast to the organized healing of CBM implants. CBM mean scores were lower than PPM scores for adhesion tenacity, surface area, and inflammation at each follow-up time for rats with omentums (P < 0.02). The CBMs had less tenacity and inflammation than PPM at each follow-up time in omentectomy groups (P < 0.008). Wound contraction was greater for PPM (P < 0.0001) for all rats. CONCLUSIONS: RCM and UBS were similar to SIS invoking reduced inflammation, adhesion, and contraction compared to PPM. The fibrotic response to PPM was unique and more intense compared to CBMs. These CBM implants appear morphologically acceptable and warrant continued investigation.

Regional anesthesia for dentistry and oral surgery.

Pain is a perception that results from activation of a specific set of receptors by noxious stimuli. Processing by the central nervous system results in the stimulus to be perceived as pain. Thermal receptors respond to temperature changes, mechanoreceptors respond to pressure, tension, stretch, and chemoreceptors respond to substances released during the inflammatory process such as prostaglandins, histamine, serotonin, and bradykinin. The current standard of veterinary medical practice is adequate pain management for all patients. Regional anesthesia is one component of overall pain management of the oral surgery/dental patient and is described step-by-step.