The use of a linear versus curvilinear oscillating saw blade for femoral head and neck excision surgery in cats.

OBJECTIVE: To determine the effects of using either a linear or curvilinear oscillating, battery-powered saw blade on the extent of bone resection, bone fissure or fragmentation, soft tissue trauma, and surgical time for femoral head and neck excision (FHNE) in feline cadavers. ANIMALS: 18 feline cadavers. METHODS: Paired feline cadaveric femora were randomly assigned to either a 10 mm linear or 12 mm curvilinear blade for FHNE by 2 surgical residents. CT of each femur pre- and postoperatively were used to create 3D reconstructions of each femur. The residual remaining or excessively resected bone volume at the ostectomy site was compared to an "ideal" ostectomy line made by a board-certified surgeon on preoperative CTs. RESULTS: There were no significant differences in residual or excessive bone resection by a saw blade (P = .84), between surgeons (P = .65), or in surgery time (P = .39). When compared to the "ideal" ostectomy, the linear saw blade removed slightly less bone compared to the curvilinear blade, but was not statistically significant (P = .82). No fissures or fractures were noted; however, the curvilinear blade removed the entire lesser trochanter in 1 cadaver and the linear blade partially removed the greater trochanter in 1 femur and 2 lesser trochanters in 2 femora. CLINICAL RELEVANCE: The use of a curvilinear blade may be a viable option for performing FHNE in cats. In vivo studies are warranted to determine its efficacy in clinical cases where FHNE is performed and the incidence of complications postoperatively.

Case Report: Adrenal Epithelial Cyst in an 11-Year-Old Leptailurus Serval.

Case Description: A serval (Leptailurus serval) presented for progressive enlargement of the right adrenal gland, which had been found incidentally on abdominal ultrasound 2 years previously and upon subsequent ultrasound examinations enlarged progressively from 1.26 to 1.43 cm. Clinical Findings: Clinical signs had not been recorded by the zookeeper, however, progressive weight gain and lethargy were reported. Computed tomography (CT) confirmed the presence of a right caudal pole adrenal mass measuring 1.8 cm. Treatment and Outcome: The right adrenal with associated mass was surgically resected via a ventral midline laparotomy that included the resection of the right phrenicoabdominal vein in association with the mass. Histopathological examination identified the mass as an epithelial cyst. Chromogranin A staining for a possible pheochromocytoma was performed but was negative. The serval recovered at the zoo without complication and has been on display for 18 months. Clinical Relevance: Epithelial adrenal cysts have not been previously reported in felids. An adrenal cyst should be included on the differential list for any animal with an enlarged, slowly growing adrenal gland mass with non-specific clinical signs.

Distraction Stabilization of Degenerative Lumbosacral Stenosis: Technique and Mid- to Long-Term Outcome in 30 Cases.

OBJECTIVE: To describe the dorsal laminectomy, annulectomy and distraction stabilization with pins and polymethylmethacrylate technique, its complications and outcome in the management of canine degenerative lumbosacral stenosis. To determine pre- and post-surgical foraminal width and vertebral step changes. STUDY DESIGN: Multi-institutional retrospective clinical study. METHODS: Medical records (2005-2020) of dogs treated (n = 30). Clinical signs, Modified Frankel Score, Texas Spinal Cord Injury Score, pain score (dorsal palpation of spine, tail dorsiflexion), imaging findings and complications were retrieved pre-operatively, perioperatively and at long-term follow-up. RESULTS: The most common presurgical imaging findings were disc protrusion (24/25) and sclerosis of the caudal end-plate of L7 (23/30). On short- to long-term assessment 18 out of 21 dogs exhibited clinical improvement and all exhibited improved pain scores (p < 0.0001). Catastrophic complications occurred in 3 dogs, and major complications occurred in 5, of which 3 required additional surgery. Mean lumbosacral step defect reduced 60% (1.8 mm ± 2.5 mm pre-surgery to 0.7mm ± 0.9mm post-surgery, p = 0.1585). Mean foraminal width significantly increased 50% long-term (3.3 mm ± 1.0 mm pre-surgery to 5.0 mm ± 0.9 mm post-surgery, p < 0.0001). CLINICAL SIGNIFICANCE: Dorsal laminectomy, annulectomy and distraction stabilization is a complex procedure which can significantly increase foraminal width, reduce pain and improve gait characteristics in dogs in the short- to long-term, and should be performed by surgeons experienced in lumbosacral pin placement.

Mid- to Long-Term Outcome after Arthroscopy and Proximal Abducting Ulnar Osteotomy Versus Arthroscopy Alone in Dogs with Medial Compartment Disease: Thirty Cases.

OBJECTIVE: The aim of this study was to determine owner-assessed mid- to long-term outcome for dogs with medial compartment disease treated arthroscopically with fragment removal with or without proximal abducting ulnar osteotomy (PAUL). STUDY DESIGN: This was a retrospective clinical study. MATERIALS AND METHODS: Records from 30 dogs with medial compartment disease treated with arthroscopy with or without PAUL were retrospectively reviewed over a 5-year period. Proximal abducting ulnar osteotomy cases were matched to arthroscopy-alone controls based on bodyweight and modified Outerbridge score. Outcome was assessed via owner questionnaire using the Canine Brief Pain Inventory (CBPI), frequency of non-steroidal anti-inflammatory drug (NSAID) administration and owner-assessed overall improvement. RESULTS: Canine Brief Pain Inventory score for dogs in the PAUL group was not significantly different from the control group (p = 0.54). Non-steroidal anti-inflammatory drug administration was similar between groups (p = 0.61) and there was no significant difference between modified Outerbridge score and outcome (p = 0.57) over a median of 43 months post-surgically (range: 7-66 months). Canine Brief Pain Inventory and NSAID use were affected by the age of the dog with dogs greater than 3 years of age at the time of surgery having a higher CBPI score and increased NSAID use regardless of the surgery that was performed. Overall, owner-assessed improvement was not different between groups (p = 0.72). CLINICAL SIGNIFICANCE: Proximal abducting ulnar osteotomy showed no owner-assessed benefit over arthroscopic medial coronoid fragment removal for dogs with medial compartment disease and modified Outerbridge score of 3 or greater. A prospective, blinded, controlled clinical trial is warranted to determine the appropriate clinical application of the PAUL procedure.

Feasibility of open-chest cardiopulmonary resuscitation through a transdiaphragmatic approach in dogs.

OBJECTIVE: To describe and evaluate the feasibility of a transdiaphragmatic (TD) approach for open-chest cardiopulmonary resuscitation (OCCPR) as an alternative to a traditional lateral thoracotomy (LT) in a canine cadaver model. STUDY DESIGN: Randomized noninferiority ex vivo study. ANIMALS: Fourteen canine cadavers weighing 17.4-30.2 kg. METHODS: An LT and a TD approach to the heart were performed in each cadaver. The order of procedures as well as an assignment to specific operators were randomized before starting the study. Data recorded included the time between incision and initiation of cardiac compressions; time between initiation of the first suture placement and closure of the intrapleural space; time between initiation of the first suture placement and final skin suture; trauma to pulmonary, cardiac, hepatic and neurovascular structures; distance between the caval foramen and diaphragmatic incision; the intercostal space entered during LT; and appropriate closure. RESULTS: The mean time between incision and initiation of cardiac compressions for the TD approach (85 ± 35 seconds) was noninferior to the LT (84 ± 28 seconds). The pleural space was closed faster after the TD approach (531 ± 276 seconds) than after the lateral approach (817 ± 294 seconds, P = .03). Total duration of closure did not differ between techniques (P = .11). There was no difference between the complication rates of each approach. CONCLUSION: The TD approach did not prolong the procedure or increase the complication rate compared with an LT. CLINICAL SIGNIFICANCE: This study provides evidence to support additional investigation of the TD approach for OCCPR to determine its efficacy and safety in live animals.

Dermoid sinus type VI associated with spina bifida and tethered cord syndrome in a French Bulldog.

A 4-mo-old French bulldog was presented with acute onset pain and reluctance to move. A tubular structure arising in the dorsal thoracic midline and extending from a cutaneous orifice into deeper tissues was palpated on physical examination. Computed tomography with sinography revealed a dermoid sinus associated with spina bifida at the level of T3-T4. On surgical exploration, the dermoid sinus was found to communicate with the dura. Histology confirmed the diagnosis and classification as a type VI dermoid sinus. The pain response and hyperesthesia were suspected to be the result of tethered cord syndrome. Complete resolution of clinical signs was appreciated post-surgery, with the patient still free of clinical signs 3 mo later.

Evaluation of the clinical effects of diet and physical rehabilitation in dogs following tibial plateau leveling osteotomy.

OBJECTIVE To assess clinical effects of an omega-3 fatty acid and protein-enriched diet, physical rehabilitation, or both in dogs following tibial plateau leveling osteotomy (TPLO) and arthroscopic surgery for cranial cruciate ligament (CCL) disease. DESIGN Randomized, prospective clinical trial. ANIMALS 48 dogs with unilateral CCL disease. PROCEDURES Dogs were randomly assigned to receive a dry omega-3 fatty acid and protein-enriched dog food formulated to support joint health (test food [TF]), a dry food formulated for maintenance of adult dogs (control food [CF]), TF plus rehabilitation (TF-R), or CF plus rehabilitation (CF-R). Data collected over 6 months included body weight, body condition score, ground reaction force data, tibial plateau angle, limb circumference measurements, subjective pain and lameness scores assigned by surgeons and dog owners, and daily activity measured by accelerometry. RESULTS Peak vertical force and vertical impulse were greater after surgery for dogs in the TF groups than in the CF groups; peak vertical force was greater after surgery in dogs that underwent rehabilitation than in those that did not. Owner scores indicated lower frequencies of lameness and signs of pain during some activities for the TF group, compared with other groups, and for the TF-R and CF-R groups, compared with the CF group. Sedentary time decreased and time spent in light-to-moderate or vigorous activity increased in all groups over time. Rehabilitation was significantly associated with greater time spent in light-to-moderate activity, regardless of diet. CONCLUSIONS AND CLINICAL RELEVANCE Feeding the TF and providing physical rehabilitation during the first 6 months after TPLO were associated with improvements in some indices of clinical outcome and function in dogs. Significant interactions between time and some outcome variables were observed, indicating further research is warranted.

Assessment of the effects of diet and physical rehabilitation on radiographic findings and markers of synovial inflammation in dogs following tibial plateau leveling osteotomy.

OBJECTIVE To determine the effects of an omega-3 fatty acid and protein-enriched diet, physical rehabilitation, or both on radiographic findings and markers of synovial inflammation in dogs following tibial plateau leveling osteotomy and arthroscopic surgery for treatment of cranial cruciate ligament disease. DESIGN Randomized, prospective clinical trial. ANIMALS 48 dogs with unilateral cranial cruciate ligament disease. PROCEDURES Dogs were randomly assigned to receive a dry omega-3 fatty acid and protein-enriched dog food formulated to support joint health (test food [TF]), a dry food formulated for adult canine maintenance (control food [CF]), TF plus rehabilitation, or CF plus rehabilitation after surgery. Synovial fluid prostaglandin (PG) E2 and interleukin-1ß concentrations, radiographic osteoarthritis scores, osteotomy site healing, and patellar ligament thickness were assessed at predetermined time points up to 6 months after surgery. RESULTS Dogs that received CF had significantly higher PGE2 concentrations over time following surgery than did dogs that received TF, regardless of rehabilitation status. Synovial fluid interleukin-1ß concentrations did not change over time in any groups. Diet and rehabilitation were both associated with osteoarthritis scores, with significantly lower scores over time for dogs that received TF versus CF and for dogs that underwent rehabilitation versus those that did not. Proportions of dogs with complete osteotomy healing 8 and 24 weeks after surgery were significantly lower for dogs that received TF than for dogs that received CF, regardless of rehabilitation status. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that feeding the TF can result in lower synovial fluid PGE2 concentrations and that both the TF and rehabilitation can reduce progression of osteoarthritis in the 6 months following tibial plateau leveling osteotomy; clinical relevance of slower osteotomy healing in dogs fed the TF was unclear.

Randomized, controlled, prospective clinical trial of autologous greater omentum free graft versus autogenous cancellous bone graft in radial and ulnar fractures in miniature breed dogs.

OBJECTIVE: To determine the rate of radiographic healing, complications, vascularization, and bone density after repair of radial and ulnar fractures in dogs <6 kg that were treated with an autogenous cancellous bone graft (BG) or free autologous omentum graft (OG). STUDY DESIGN: Prospective, randomized, controlled clinical trial with owners/radiologists blinded to treatment. ANIMALS: 25 dogs with naturally occurring traumatic radial/ulnar fractures. METHODS: Fractures underwent plate fixation with OG or BG. Power Doppler ultrasonographic, computed tomographic (CT), and radiographic examinations of the affected antebrachium were performed preoperatively and every 3 weeks postoperatively until healed. Pressure-sensitive walkway gait analysis and owner and veterinarian assessments were obtained preoperatively (0 weeks) and 3, 6, 9, 12, and 24 weeks postoperatively. RESULTS: Owner/veterinarian assessments improved postoperatively but did not differ significantly between groups. The improvement in peak vertical force/vertical impulse was greater in dogs with OG than in those with BG, beginning 3 weeks postoperatively. Radiographic healing occurred earlier in bones treated with OG (median, 9 weeks) than in those treated with BG (12 weeks). Cortical bone density derived from CT of the distal ulna was higher in bones with BG compared with bones with OG. Signal intensity and the number of vessels in the fracture callus declined over time in both groups, according to results of ultrasonography. However, bones retained more vessels and greater signal intensity when treated with OG compared with treatment with BG, according to multiple views at 6 and 9 weeks postoperatively. CONCLUSION: Omental grafting was not associated with major complications, and it accelerated bone healing and return to weight bearing in dogs. CLINICAL SIGNIFICANCE: Omental grafting should be considered as an adjunct to stabilization of antebrachial fractures in toy and small breed dogs.

Preoperative low level laser therapy in dogs undergoing tibial plateau levelling osteotomy: A blinded, prospective, randomized clinical trial.

OBJECTIVES: To evaluate the influence of preoperative low-level laser therapy (LLLT) on therapeutic outcomes of dogs undergoing tibial plateau levelling osteotomy (TPLO). METHODS: Healthy dogs undergoing TPLO were randomly assigned to receive either a single preoperative LLLT treatment (800-900 nm dual wavelength, 6 W, 3.5 J/cm2, 100 cm2 area) or a sham treatment. Lameness assessment and response to manipulation, as well as force plate analysis, were performed preoperatively, then again at 24 hours, two weeks, and eight weeks postoperatively. Radiographic signs of healing of the osteo-tomy were assessed at eight weeks postoperatively. RESULTS: Twenty-seven dogs (27 stifles) were included and no major complications occurred. At eight weeks postoperatively, a significant difference in peak vertical force analysis was noted between the LLLT (39.6% ± 4.7%) and sham groups (28.9% ± 2.6%), (p <0.01 Time, p <0.01 L). There were no significant differences noted between groups for all other parameters. The age of dogs in the LLLT group (6.6 ± 1.6 years) was greater than that for the sham group (4.5 ± 2.0, p <0.01). Although not significant, a greater proportion of LLLT dogs (5/8) had healed at the eight-week time point than in the sham group (3/12) despite the age difference (p = 0.11) Clinical significance: The results of this study demonstrate that improved peak vertical force could be related to the preoperative use of LLLT for dogs undergoing TPLO at eight weeks postoperatively. The use of LLLT may improve postoperative return to function following canine osteotomies and its use is recommended.

Augmentation of arthrodesis in dogs using a free autogenous omental graft.

A technique for using free autogenous omental grafting with arthrodesis in dogs is described and radiographic osseous union and complications after surgery are evaluated. This retrospective study matched body weight and procedure type for 8 cases of pancarpal arthrodesis, 4 cases of pantarsal arthrodesis, and 2 cases of partial tarsal arthrodesis in dogs with omental and cancellous bone autograft (OBG group) and with cancellous bone autograft alone (BG group). Radiographs were reviewed 9 to 12 weeks after surgery to compare scores of radiographic osseous union and it was found that the OBG group had higher scores than the BG group. The BG group had significantly more major complications that required re-operation for implant removal or treatment of a deep infection compared to the OBG group. Overall, free autogenous omental grafts may be used to augment arthrodesis in dogs without significant morbidity and further investigation of its use to reduce major complications and speed bone healing are warranted.

Augmentation de l'arthrodèse chez les chiens en utilisant une greffe omentale autogène libre. Cette étude décrit une technique de l'utilisation d'une greffe omentale autogène avec une arthrodèse chez les chiens et elle évalue l'union osseuse radiographique et les complications après la chirurgie. L'étude rétrospective a jumelé le poids corporel et le type d'intervention pour 8 cas d'arthrodèse pancarpienne, 4 cas d'arthrodèse pantarsienne et 2 cas d'arthrodèse partielle du tarse chez des chiens avec une autogreffe de l'os spongieux (groupe OBG) et avec une autogreffe de l'os spongieux seulement (groupe BG). On a évalué les radiographies de 9 à 12 semaines après la chirurgie pour comparer les notes d'union osseuse radiographique et on a constaté que le groupe OBG avait des notes supérieures à celles du groupe BG. Il s'est produit un nombre significativement supérieur de complications majeures dans le groupe BG qui ont exigé une nouvelle opération pour l'enlèvement de l'implant ou le traitement d'une infection profonde comparativement au groupe OBG. En général, les greffes omentales autogènes libres peuvent être utilisées pour augmenter l'arthrodèse chez les chiens sans morbidité significative et de nouvelles études de leur utilisation pour réduire les complications majeures et accélérer la guérison osseuse sont justifiées.(Traduit par Isabelle Vallières).

Synoviocyte neotissues towards in vitro meniscal tissue engineering.

Meniscal injuries are a common cause of pain and osteoarthritis in dogs. We describe here the production of synoviocyte-derived autologous neotissues for potential application in meniscal tissue engineering, via two different culture techniques: contracted or tensioned synthesis of synoviocyte neotissues. Synoviocytes were obtained during routine stifle arthroscopy and cultured from 14 dogs with naturally occurring osteoarthritis of the stifle. Neotissues were analyzed for meniscal-like matrix components and their gene expression, inflammatory gene expression, and cell viability. Tension improved cell viability, and, independent of cell viability, fibrochondrogenic activity by promoting expression of collagen type 1 and aggrecan genes and attenuating gene expression of IL-6. Through this mechanism tension increased collagen protein content and chondrogenic index of neotissues. Alpha smooth muscle actin was present in all neotissues and was responsible for grossly visible contractile behavior. Application of tension to synoviocytes may be a viable culture method towards in vitro meniscal tissue engineering.

Inter- and intratester reliability of anthropometric assessment of limb circumference in labrador retrievers.

OBJECTIVE: To report a standardized method of, and determine inter- and intratester reliability for, anthropometric assessment of limb circumference in dogs. STUDY DESIGN: Prospective blinded study. ANIMALS: Labrador Retrievers (n = 20). METHOD: Unsedated dogs were manually restrained in lateral recumbency and triplicate measurements of limb circumference at the level of the proximal antebrachium, mid brachium, proximal crus, and mid-thigh were made using the Gulick II tape measure in the morning and afternoon of the same day. Observers were blinded to measurements made during each occasion and those made by co-observers. Estimates of inter- and intratester reliability were made for first and mean measurements using intra-class correlation coefficients (ICC). RESULTS: Measurements of the proximal antebrachium were made with moderate to fair intratester reliability by all observers with ICC's ranging from 0.68-0.78 (1st measurement) and 0.67-0.78 (mean measurement), and moderate to fair intertester reliability with ICC's of 0.66-0.68 (1st measurement) and 0.70-0.72 (mean measurement). Measurements of the brachium, crus, and thigh typically had poor inter- and intratester reliability, ICC < 0.5. CONCLUSION: Using the described method of muscle measurement in Labrador Retrievers only measurement of the proximal antebrachium was reliable; a single (1st) measurement was as reliable as using the mean of triplicate measurements.

Shoulder arthrodesis in 14 dogs.

OBJECTIVES: To report surgical technique and clinical outcome of shoulder arthrodesis in dogs. STUDY DESIGN: Multicenter clinical case series. ANIMALS: Dogs (n = 14). METHODS: Shoulder arthrodesis featured craniolateral plate and screw application, with application of a 2nd plate and screws craniolaterally or caudolaterally in 5 shoulders. Implants included the locking string of pearls (SOP)™ plate in 7 shoulders. Subjective preoperative, 5-8 weeks postoperative, and 11-16 weeks postoperative clinical and radiographic findings were documented. Owner questionnaire evaluation of outcome was performed 6-20 months postoperatively. RESULTS: Mean angle of arthrodesis was 114° (range 102°-122°). Progression of arthrodesis was noted in 13/14 cases at both the 5-8 and 11-16 weeks postoperative radiographic assessments. Nine complications occurred in 7/14 dogs, graded as catastrophic in 2/9, major in 2/9, and minor in 5/9. Where morbidity was successfully managed, 11-16-week and 6-10-month postoperative limb function was positive on both veterinary and owner evaluations in almost all cases, and in several, functional lameness was considered sufficiently mild as to be imperceptible on subjective veterinary evaluation. Where present, limb circumduction was noted as the major feature of persistent lameness. CONCLUSIONS: Shoulder arthrodesis in dogs results in acceptable limb function and should be considered for the management of debilitating shoulder pathology despite a high incidence of complications. Application of the SOP plate to aid shoulder arthrodesis warrants further study.

Minimally invasive synovium harvest for potential use in meniscal tissue engineering.

Tissue engineering is being investigated as a means for treating avascular meniscal injury or total meniscal loss in human and veterinary patients. The purpose of this study was to determine if an arthroscopic tissue shaver can be used to collect viable synoviocytes for in vitro culture during therapeutic stifle arthroscopy, with the long term goal of producing autologous meniscal fibrocartilage for meniscal tissue engineering. Synovium was harvested arthroscopically from 13 dogs with naturally occurring cranial cruciate ligament deficiency and obtained from 5 dogs with patellar luxation via arthrotomy. Cells harvested via arthroscopy and arthrotomy were treated with a chondrogenic growth factor protocol and analyzed for meniscal-like matrix constituents including collagens type I, II, and glycosaminoglycans. Arthrotomy and Arthroscopic origin cells formed contracted tissues containing collagen I, II and small amounts of GAG. These surgical methods provide clinically relevant access to synoviocytes for potential use in meniscal tissue engineering.

Gastric smooth muscle hamartoma in a cat.

An 11-year-old cat presented for evaluation of intermittent vomiting, constipation and hyporexia of 3 weeks duration. Ultrasonographic and endoscopic examination revealed a soft tissue mass adjacent to the lower gastro-esophageal sphincter. Surgical excision of the mass was successfully performed resulting in a resolution of clinical signs. Histologically the mass was consistent with a smooth muscle hamartoma. At follow-up 7 months after surgery, the cat remained free from clinical signs.

Achilles tendon repair in dogs using the semitendinosus muscle: surgical technique and short-term outcome in five dogs.

OBJECTIVE: To describe augmentation of primary Achilles tendon repair using suture with a semitendinosus muscle flap and report outcome in 5 dogs. STUDY DESIGN: Prospective clinical study. ANIMALS: Dogs (n=5) with Achilles tendon rupture (n=6). METHODS: After tendon repair with #2 polypropylene in a 3-loop pulley suture pattern, the lateral one-half of the semitendinosus muscle was transected from the ischium, rotated distally then sutured with #2 polypropylene to the calcaneus in a 3-loop pulley pattern. The epitenon was sutured to the muscle flap fascia with interrupted sutures. All dogs had a bivalved cast for 2 weeks then a cranial splint for 2-6 weeks. Lameness scores (0=stands and walks normally to 4=non-weight-bearing lameness, plantigrade stance on affected pelvic limb) were determined every 2-3 weeks postoperatively for 12 weeks. Outcome was determined from telephone questionnaire of owners. RESULTS: Four had lameness scores of 0, the 5th had a score of 1 at 12 weeks. Three owners were very satisfied with outcome. Minor complications included cast sores (2 dogs), infection (2), and acute swelling (1); 1 major complication occurred (infection resulting in reoperation). CONCLUSIONS: Semitendinosus flap augmentation resulted in early return to function without prolonged postoperative immobilization. Three dogs returned to full work/activity after repair. CLINICAL RELEVANCE: Augmentation of primary Achilles tendon repair with a semitendinosus flap can be considered in dogs with chronic rupture but further investigation of the long-term outcome using this technique is needed.

Randomized, blinded, placebo-controlled clinical trial of N-acetylcysteine in dogs with spinal cord trauma from acute intervertebral disc disease.

STUDY DESIGN: The effect of N-acetylcysteine administration intravenously before hemilaminectomy surgery on neurologic outcome and 15F 2t isoprostane excretion in dogs was examined in a blinded, placebo-controlled trial. OBJECTIVE: To determine the effect of N-acetylcysteine administration on urinary 15F 2t isoprostane excretion and neurologic outcome following hemilaminectomy for intervertebral disc disease. SUMMARY OF BACKGROUND DATA: Oxidative stress is a mediator of secondary injury to the spinal cord following trauma. Acute intervertebral disc disease is associated with increased oxidative damage in dogs. N-acetylcysteine has preserved neurologic function following experimental spinal cord injury. METHODS: Seventy dogs with naturally occurring acute intervertebral disc disease were administered either with saline placebo or N-acetylcysteine intravenously before hemilaminectomy surgery. Serial neurologic examinations were performed before and 1, 2, 7, 14, and 42 days following treatment. Urinary excretion of 15F 2t isoprostane excretion was determined before treatment and 1 hour after surgery. RESULTS: Analysis of subjective data did not reveal any significant effect of N-acetylcysteine on neurologic outcome or rate of improvement of neurologic score in the 42 days following treatment. Urinary 15F 2t isoprostane excretion was not significantly different between treatment groups (P > 0.05). CONCLUSION: N-acetylcysteine intravenously before hemilaminectomy has no effect on urinary 15F 2t isoprostane excretion or neurologic outcome. Treatment of dogs with the antioxidant N-acetylcysteine before hemilaminectomy, while not detrimental, does not affect neurologic outcome in the 42 days following surgery.

Concentrations of 15F2t isoprostane in urine of dogs with intervertebral disk disease.

OBJECTIVE: To measure 15F(2t) isoprostane concentrations in the urine of dogs undergoing ovariohysterectomy (OHE) and dogs undergoing surgery because of intervertebral disk disease (IVDD) and to assess relationships between urinary concentrations of 15F(2t) isoprostanes and neurologic score in dogs with IVDD. ANIMALS: 11 dogs undergoing OHE and 32 dogs with IVDD undergoing hemilaminectomy. PROCEDURES: Paired urine samples were obtained at induction of anesthesia and approximately 1 hour after OHE (controls) and were collected from dogs with IVDD at induction of anesthesia (28 samples) and approximately 1 hour after hemilaminectomy (31 samples); 26 paired urine samples were obtained from dogs with IVDD. Urinary isoprostane concentrations were measured by use of a commercial ELISA, and results were adjusted on the basis of urinary creatinine concentrations. Differences in the mean isoprostane-to-creatinine ratio were analyzed. Neurologic score was determined in dogs with IVDD by use of the modified Frankel scoring system. RESULTS: Urinary isoprostane-to-creatinine ratios were significantly higher in dogs with IVDD than in control dogs before and after surgery. There was no significant difference between values before and after surgery for either group. There was a significant correlation of neurologic score and urinary isoprostane-to-creatinine ratio because dogs that had higher neurologic scores (ie, less severely affected) generally had higher isoprostane-to-creatinine ratios. CONCLUSIONS AND CLINICAL RELEVANCE: Urinary isoprostane-to-creatinine ratios were higher in dogs with IVDD before and after surgery. Analysis of these data suggests that dogs with IVDD are in a state of oxidative stress and that preemptive treatment with antioxidants warrants further investigation.

Measurement of urinary 11-dehydro-thromboxane B2 excretion in dogs with gastric dilatation-volvulus.

OBJECTIVE: To measure 11-dehydro-thromboxane B2 (11-dTXB2) in urine of healthy control dogs, dogs undergoing ovariohysterectomy, and dogs with gastric dilatation-volvulus (GDV) and assess the relationship between urinary 11-dTXB2 concentrations in dogs with GDV and postoperative outcomes. SAMPLE POPULATION: Urine samples from 15 nonsurgical control dogs, 12 surgical control dogs, and 32 dogs with GVD. PROCEDURE: Urine samples were obtained from healthy pet dogs (ie, nonsurgical control dogs), dogs undergoing ovariohysterectomy at anesthetic induction and 1 hour following surgery (ie, surgical control dogs), and dogs with GDV at hospital admission and 1 hour following surgical derotation of the stomach (ie, GDV dogs). Urinary 11-dTXB2 concentrations were determined with an ELISA and normalized to urinary creatinine (Cr) concentrations by calculation of the 11-dTXB2 -to-Cr ratio. Differences in median 11-dTXB2 -to-Cr ratios among dogs and before and after surgery were analyzed. RESULTS: Urinary 11-dTXB2-to-Cr ratios did not differ between nonsurgical control dogs and surgical control dogs before or after surgery. Urinary 11-dTXB2-to-Cr ratios were significantly higher in GDV dogs at the time of hospital admission and 1 hour after surgery, compared with those of nonsurgical control dogs. Postoperative urine samples from GDV dogs had significantly higher 11-dTXB2-to-Cr ratios than postoperative urine samples from surgical control dogs. Median urinary 11-dTXB2-to-Cr ratios increased significantly in GDV dogs that developed postoperative complications. CONCLUSIONS AND CLINICAL RELEVANCE: Urinary 11-dTXB2 concentration is increased in GDV dogs at the time of hospital admission and after surgical derotation of the stomach, compared with that of healthy dogs. An increased urinary 11-dTXB2-to-Cr ratio following surgery is associated with an increased incidence of postoperative complications in dogs with GDV.