Preoperative management and postoperative complications in 9 dogs undergoing surgical treatment of thymic-associated myasthenia gravis.

Objective: Thymoma-associated paraneoplastic syndromes in dogs and cats include myasthenia gravis, hypercalcemia, exfoliative dermatitis, erythema multiforme, T-cell lymphocytosis, myocarditis, anemia, and polymyositis. Paraneoplastic myasthenia gravis (MG) is the most commonly reported paraneoplastic syndrome in dogs with thymic epithelial tumors. The objective of this study was to examine cases of canine thymic-associated MG treated surgically, with the specific objective of providing an updated clinical picture of the preoperative management, postoperative complications, and outcomes of these cases. Animals: Nine dogs with paraneoplastic MG underwent surgical removal of a thymic epithelial tumor. Procedure: Medical records of dogs with MG that received surgical treatment of a thymic epithelial tumor between January 1, 2012 and October 1, 2022 were obtained from 4 veterinary teaching hospitals. Descriptions of perioperative MG management, complications, and outcomes were reported. Results: Six of the 9 dogs received medical therapy for MG, with either a cholinesterase inhibitor (4 dogs) or a cholinesterase inhibitor and immunosuppressive agent (2 dogs), before surgery. The median duration of medical therapy for MG before surgery was 7.5 d (range: 2 to 60 d). Three of 9 dogs experienced immediate postoperative complications and were euthanized. Six of 9 dogs (66.6%) survived to discharge and 3 of 6 dogs that survived to discharge were alive at the time of writing. At the time of writing, 3 of 6 dogs had complete resolution of clinical signs attributable to MG and 2 of 6 had partial resolution. The median time from surgery to resolution of clinical signs of MG in these dogs was 63 d (range: 2 to 515 d). Conclusion: Dogs with thymic epithelial tumors and paraneoplastic MG are at a high risk for perioperative complications. Clinical relevance: The findings of this study corroborate previous literature stating that paraneoplastic MG is a poor prognostic indicator for dogs with thymic epithelial tumors, while also highlighting the variation in approaches to clinical management of thymic-associated MG in veterinary medicine and the lack of established protocols guiding perioperative management.

Prise en charge préopératoire et complications postopératoires chez 9 chiens subissant un traitement chirurgical de la myasthénie grave associée au thymus. Objectif: Les syndromes paranéoplasiques associés au thymome chez le chien et le chat comprennent la myasthénie grave, l'hypercalcémie, la dermatite exfoliative, l'érythème polymorphe, la lymphocytose à cellules T, la myocardite, l'anémie et la polymyosite. La myasthénie paranéoplasique (MG) est le syndrome paranéoplasique le plus fréquemment rapporté chez les chiens atteints de tumeurs épithéliales thymiques. L'objectif de cette étude était d'examiner les cas de MG canine associée au thymus traités chirurgicalement, dans le but spécifique de fournir un tableau clinique actualisé de la prise en charge préopératoire, des complications postopératoires et des résultats de ces cas. Animaux: Neuf chiens atteints de MG paranéoplasique ont subi l'ablation chirurgicale d'une tumeur épithéliale thymique. Procédure: Les dossiers médicaux des chiens atteints de MG ayant reçu un traitement chirurgical d'une tumeur épithéliale thymique entre le 1er janvier 2012 et le 1er octobre 2022 ont été obtenues auprès de 4 hôpitaux universitaires vétérinaires. Des descriptions de la prise en charge péri-opératoire de la MG, des complications et des résultats ont été rapportées. Résultats: Six des 9 chiens ont reçu un traitement médical pour la MG, avec soit un inhibiteur de la cholinestérase (4 chiens), soit un inhibiteur de la cholinestérase et un agent immunosuppresseur (2 chiens), avant la chirurgie. La durée médiane du traitement médical de la MG avant la chirurgie était de 7,5 jours (plage : 2 à 60 jours). Trois des neuf chiens ont présenté des complications postopératoires immédiates et ont été euthanasiés. Six des 9 chiens (66,6 %) ont survécu jusqu'à leur sortie et 3 des 6 chiens qui ont survécu jusqu'à leur sortie étaient en vie au moment de la rédaction. Au moment de la rédaction de cet article, 3 chiens sur 6 présentaient une résolution complète des signes cliniques attribuables à la MG et 2 chiens sur 6 présentaient une résolution partielle. Le délai médian entre l'intervention chirurgicale et la résolution des signes cliniques de MG chez ces chiens était de 63 jours (plage : 2 à 515 jours). Conclusion: Les chiens atteints de tumeurs épithéliales thymiques et de MG paranéoplasique présentent un risque élevé de complications périopératoires. Pertinence clinique: Les résultats de cette étude corroborent la littérature antérieure indiquant que la MG paranéoplasique est un indicateur de mauvais pronostic pour les chiens atteints de tumeurs épithéliales thymiques, tout en soulignant également la variation des approches de prise en charge clinique de la MG associée au thymus en médecine vétérinaire et le manque de protocoles établis de gestion guidant les interventions périopératoires.(Traduit par Dr Serge Messier).

Veterinary house officer perceptions of dimensions of well-being during postgraduate training.

OBJECTIVE: To describe veterinary house officers' perceptions of dimensions of well-being during postgraduate training and to identify potential areas for targeted intervention. SAMPLE: 303 house officers. PROCEDURES: A 62-item questionnaire was generated by use of an online platform and sent to house officers at participating institutions in October 2020. Responses were analyzed for trends and associations between selected variables. RESULTS: 239 residents, 45 rotating interns, and 19 specialty interns responded to the survey. The majority of house officers felt that their training program negatively interfered with their exercise habits, diet, and social engagement. House officers reported engaging in exercise significantly less during times of clinical responsibility, averaging 1.6 exercise sessions/wk (SD ± 0.8) on clinical duty and 2.4 exercise sessions/wk (SD ± 0.9) when not on clinical duty (P < 0.001). Ninety-four percent of respondents reported experiencing some degree of anxiety regarding their physical health, and 95% of house officers reported feeling some degree of anxiety regarding their current financial situation. Overall, 47% reported that their work-life balance was unsustainable for > 1 year; there was no association between specialty and sustainability of work-life balance. Most house officers were satisfied with their current training program, level of clinical responsibility, and mentorship. CLINICAL RELEVANCE: Veterinary house officers demonstrated a poor balance between the demands of postgraduate training and maintenance of personal health. Thoughtful interventions are needed to support the well-being of veterinary house officers.

Distribution of histopathologic types of primary pulmonary neoplasia in dogs and outcome of affected dogs: 340 cases (2010-2019).

OBJECTIVE: To provide updated information on the distribution of histopathologic types of primary pulmonary neoplasia in dogs and evaluate the effect of postoperative adjuvant chemotherapy in dogs with pulmonary carcinoma. ANIMALS: 340 dogs. PROCEDURES: Medical records of dogs that underwent lung lobectomy for removal of a primary pulmonary mass were reviewed, and histopathologic type of lesions was determined. The canine lung carcinoma stage classification system was used to determine clinical stage for dogs with pulmonary carcinoma. RESULTS: Pulmonary carcinoma was the most frequently encountered tumor type (296/340 [87.1%]), followed by sarcoma (26 [7.6%]), adenoma (11 [3.2%]), and pulmonary neuroendocrine tumor (5 [1.5%]); there was also 1 plasmacytoma and 1 carcinosarcoma. Twenty (5.9%) sarcomas were classified as primary pulmonary histiocytic sarcoma. There was a significant difference in median survival time between dogs with pulmonary carcinomas (399 days), dogs with histiocytic sarcomas (300 days), and dogs with neuroendocrine tumors (498 days). When dogs with pulmonary carcinomas were grouped on the basis of clinical stage, there were no significant differences in median survival time between dogs that did and did not receive adjuvant chemotherapy. CLINICAL RELEVANCE: Results indicated that pulmonary carcinoma is the most common cause of primary pulmonary neoplasia in dogs; however, nonepithelial tumors can occur. Survival times were significantly different between dogs with pulmonary carcinoma, histiocytic sarcoma, and neuroendocrine tumor, emphasizing the importance of recognizing the relative incidence of these various histologic diagnoses. The therapeutic effect of adjuvant chemotherapy in dogs with pulmonary carcinoma remains unclear and warrants further investigation.

Diagnosis and treatment of truncal cutaneous pythiosis in a dog.

CASE DESCRIPTION: A 4-year-old spayed female Boxer was evaluated for a cutaneous mass located on the dorsum. The mass had been present for 6 weeks and was increasing in size. CLINICAL FINDINGS: A mass of approximately 10 cm in diameter was detected on the dorsum cranial to the right ilial wing. Histologic examination of a tissue sample from the mass led to the diagnosis of cutaneous pythiosis. Computed tomography of the abdomen and the mass were performed and revealed a contrast-enhancing soft tissue mass of the dorsum and enlarged intra-abdominal lymph nodes. TREATMENT AND OUTCOME: The dog underwent surgical excision of the cutaneous mass, including 5-cm skin margins and deep margins of 2 fascial planes. The mass was completely excised on the basis of results of histologic examination of surgical margins. The dog received itraconazole and terbinafine by mouth for 3 months following surgery. Recheck examination at 20 months postoperatively showed no signs of recurrence of pythiosis at the surgical site. CLINICAL RELEVANCE: Aggressive surgical excision in combination with medical treatment resulted in a favorable long-term (> 1 year) outcome in this dog. Thorough workup including diagnostic imaging and lymph node evaluation is recommended. If surgery is to be performed, skin margins of 5 cm and deep margins of 2 fascial planes are recommended.

Histopathological confirmation of polyneuropathy in 11 dogs with laryngeal paralysis.

Acquired laryngeal paralysis (LP) is an important cause of upper airway obstruction in dogs. We hypothesize that LP may be part of a generalized polyneuropathy complex. Electro-diagnostic studies were performed in six dogs, and histopathological studies of muscle and nerve biopsies were obtained from 11 dogs diagnosed with acquired LP. Abnormalities in electrodiagnostic procedures were consistent with a generalized polyneuropathy. Loss of large-caliber nerve fibers and axonal degeneration were identified in nerve biopsies, and neurogenic atrophy was observed in muscle specimens. Abnormalities in electrodiagnostic studies and histopathology provide evidence that LP may be part of a generalized polyneuropathy. Establishing a diagnosis of a more involved disease process is relevant for long-term prognosis.

Comparison of contact mechanics of three meniscal repair techniques and partial meniscectomy in cadaveric dog stifles.

OBJECTIVE: To evaluate the biomechanical effect of horizontal, vertical, and cruciate suture repairs and partial meniscectomy on contact mechanics of dog stifles. STUDY DESIGN: Ex vivo experimental study. SAMPLE POPULATION: Cadaveric canine stifles (n=24). METHODS: Simulated bucket handle medial meniscal tears were created in cadaveric dog stifles. Tears were treated with 1 of 3 suture repair techniques or partial meniscectomy. Instantaneous contact area (CA), mean contact pressure (MCP), and peak contact pressure (PCP) measurements were recorded with a pressure sensing system. CA, MCP, and PCP for intact stifles (control), stifles with simulated tears, and stifles after treatment were recorded and compared using 1-way repeated measures ANOVA. RESULTS: Stifles with bucket handle tears had significantly decreased CA, increased MCP and increased PCP when compared with control. All meniscal repair techniques reestablished normal contact mechanics. When comparing meniscal repair and partial meniscectomy, stifles with partial meniscectomy had approximately 35% lower CA, 57% higher MCP, and 55% higher PCP than stifles undergoing repair. CONCLUSIONS: Contact mechanics obtained from each repair technique were mechanically superior to partial meniscectomy. Performing meniscal repair instead of partial meniscectomy in dogs with select meniscal tears may mitigate the development of degenerative joint disease. Criteria for selection of candidates for meniscal repair should be confirmed with future studies. CLINICAL RELEVANCE: Based on this ex-vivo model, meniscal repair will restore normal contact mechanics. Consideration should be given to meniscal repair as treatment for peripheral meniscal tears located in the vascular zone if the meniscal parenchyma is normal.

Postmortem evaluation of surgery site leakage by use of in situ isolated pulsatile perfusion after partial liver lobectomy in dogs.

OBJECTIVE: To evaluate postmortem surgery site leakage by use of in situ isolated pulsatile perfusion after partial liver lobectomies. ANIMALS: 10 healthy mixed-breed male dogs. PROCEDURES: Dogs were anesthetized, and 5 surgical techniques (pretied suture loop, energy-based sealer-divider, harmonic scalpel, suction with clip application, or suction with use of a thoracoabdominal stapler) were used to perform 5 partial liver lobectomies in each dog. Dogs were euthanatized, and the portal vein and hepatic artery were cannulated and perfused with a modified kidney perfusion machine (pulsatile flow for arterial perfusion and nonpulsatile flow for portal perfusion). Lobectomy sites were inspected for leakage of perfusate, and time until detection of leakage was recorded. The techniques in each dog were ranked on the basis of time until leakage. Time until leakage and rankings for each surgical technique were analyzed by use of an ANOVA. RESULTS: Leakage of perfusate was recorded in 44 lobes at supraphysiologic pressures. Of the 6 lobes without leakage, a pretied suture loop procedure was performed in 5 and a harmonic scalpel procedure was performed in 1. Time until leakage and the ranking differed significantly between the pretied suture loop and the other techniques. Time until leakage and ranking did not differ significantly among the other techniques. CONCLUSIONS AND CLINICAL RELEVANCE: Time until leakage of perfusate was greater for the pretied suture loop technique than for the other techniques, and that technique did not fail in 5 of 10 lobes. However, all techniques appeared to be safe for clinical use.

Contact mechanics of simulated meniscal tears in cadaveric canine stifles.

OBJECTIVE: To evaluate the biomechanical effects of 5 types of meniscal lesions on contact mechanics in the canine stifle. STUDY DESIGN: Experimental study. ANIMALS: Cadaveric canine stifles (n=12 pair). METHODS: Medial meniscal lesions (radial, vertical longitudinal, nonreducible bucket handle, flap, and complex tears) were simulated in cadaveric stifles. A contact map was recorded from each tear type and contact area (CA) and peak contact pressure (PCP) from each tear type were compared. RESULTS: A significant difference in PCP was detected between control and nonreducible bucket handle, flap, and complex tears. PCP increased by >45% in nonreducible bucket handle, flap, and complex meniscal tears when compared with control. No significant difference was found in PCP between control and radial and vertical longitudinal tears. No significant difference was found in CA between any of the meniscal conditions. CONCLUSIONS: Nonreducible bucket handle, flap, and complex tears cause a significant increase in PCP. Radial and vertical longitudinal tears had a minimal impact on the contact pressures of the medial compartment of the stifle. CLINICAL RELEVANCE: Based on this ex vivo model, we support the clinical recommendation of debriding nonreducible bucket handle, flap, and complex tears because the injured portion of the meniscus no longer contributes significantly to the function of the meniscus. Radial and vertical longitudinal tears do not cause a change in contact mechanics allowing consideration of nonsurgical treatment and meniscal repair, respectively. Future experimental and clinical studies should aim to refine the treatment of specific meniscal injuries.

Effect of meniscal release on rate of subsequent meniscal tears and owner-assessed outcome in dogs with cruciate disease treated with tibial plateau leveling osteotomy.

OBJECTIVE: To determine and compare rates of meniscal tears after tibial plateau leveling osteotomy (TPLO) among 3 groups of dogs based on treatment method: arthrotomy with meniscal release (openR), arthrotomy without meniscal release (openNR), arthroscopy without meniscal release (scopeNR), and compare long term owner-assessed outcomes for the same groups. STUDY DESIGN: Retrospective cohort study. SAMPLE POPULATION: Stifles (n=254) of dogs that had TPLO. METHODS: The three groups were compared for significant (P<.05) differences in rate of subsequent tears using a chi(2) test. Odds ratios for likelihood of subsequent meniscal tears were determined. Data for signalment, outcome, time to peak function, and time to subsequent tear were compared for significant differences using ANOVA, t-test, or rank sum test. RESULTS: Subsequent meniscal tears were diagnosed in 16 cases (6.3%). Of dogs with subsequent meniscal tears, 9 had openNR, 4 had openR, and 3 had scopeNR; the proportion of subsequent meniscal tears was significantly different (P=.035) among groups. Odds ratio indicated that subsequent meniscal tear was 3.8 times more likely to occur for openNR than openR or scopeNR. No significant differences among groups were noted for measures of outcome. CONCLUSIONS: Meniscal release did not reduce the rate of subsequent meniscal tears when compared with cases treated arthroscopically or when compared with all cases combined, but may be advantageous when meniscal pathology cannot be comprehensively assessed in the cranial cruciate deficient stifle. Meniscal release had no effects on owner-assessed outcome as determined in this study. CLINICAL RELEVANCE: The low rates of subsequent meniscal tears in conjunction with the relatively high and equivocal levels of owner-assessed outcome and time to peak function for all 3 treatment groups suggest that any of these surgical management strategies can be considered acceptable. We suggest that a meniscal release be performed when complete and thorough exploration of the joint and meniscus cannot be, or are not, performed.

Toggle rod stabilization for treatment of hip joint luxation in dogs: 62 cases (2000-2005).

OBJECTIVE: To determine outcome of open toggle rod stabilization in dogs with luxation of the hip joint. Design-Retrospective case series. ANIMALS: 62 dogs. PROCEDURES: Information on signalment, surgical procedure, and postoperative care was obtained from the medical records. A questionnaire was sent to all owners to solicit follow-up information. RESULTS: The distribution for time between luxation and surgery was bimodal, with 24 (39%) dogs examined < or = 2 days after injury and 23 (37%) examined > 7 days after injury. Postoperative complications developed in 16 of the 62 (26%) dogs, with complications developing within 1 week after surgery in 10 of the 16. The most common complication was reluxation, which occurred in 7 dogs. Dogs in which surgery time was < 2 hours were significantly less likely to have a reluxation (2/40 [5%]) than were dogs in which surgery time was > or = 2 hours (5/22 [23%]). When asked to rate current limb function (0 = no lameness and 5 = non-weightbearing lame) a minimum of 6 months after surgery, 23 of 27 (85%) owners indicated a score of 0 or 1. CONCLUSIONS AND CLINICAL RELEVANCE: Results of the present study suggest that toggle rod stabilization is an effective treatment for hip joint luxation in dogs. However, complications, particularly reluxation, were common.