A lateral surgical approach to the larynx may impair cervical esophageal function in dogs.

OBJECTIVE: To determine whether muscle-sparing laryngoplasty results in fewer changes in swallowing function compared to standard surgical treatment for laryngeal paralysis. ANIMALS: 12 clinically normal sexually intact male Beagles. PROCEDURES: Group A dogs (n = 4) had a standard approach to the larynx, with left arytenoid cartilage lateralization. Group B dogs (n = 4) had a muscle-sparing laryngoplasty performed with the thyropharyngeus muscle fibers bluntly separated, and the cricoarytenoideus dorsalis muscle spared. Pre- and 24-hour postoperative fluoroscopic swallowing studies were performed and graded. Larynges were harvested after humane euthanasia, and glottic area was measured. Group C dogs (n = 4) acted as controls, with surgical dissection ending lateral to the thyropharyngeus muscle, arytenoid lateralization not performed, and the dogs not euthanized. The study was performed between October 15, 2011 and May 15, 2021. RESULTS: Changes in pharyngeal and upper esophageal sphincter function were not detected in any group. There was no difference in glottic area between treatment groups. Aspiration of liquid was not a consistent finding. Two dogs in each treatment group developed moderate to severe cervical esophageal paresis. This did not occur in control dogs. CLINICAL RELEVANCE: We found no evidence to support our hypothesis that muscle-sparing laryngoplasty results in less severe changes in swallowing function compared to a standard technique. The cervical esophageal paresis identified in both treatment groups could increase the risk of postoperative aspiration pneumonia in dogs treated for laryngeal paralysis via a lateral approach to the larynx. Further study to determine the frequency, cause, and duration of esophageal dysfunction is warranted.

Creation of a Continent Urinary Bladder Reservoir Vascularized by Omentum as a Possible Surgical Option for Canine Trigonal/Urethral Urothelial Carcinoma.

Surgical procedures that maintain continence with minimal complication following resection of trigono-urethral urothelial carcinoma (UC) are limited in canines; therefore, palliative options are often pursued. A feasible tumor resection option may improve disease control and survival. The study's objective was to evaluate a continent urine reservoir created from the urinary bladder body and vascularized solely by omentum. We hypothesized that a viable urine reservoir could be created, and staged omentalization would provide improved vascularity. Nine normal female Beagles were randomized to one of three groups. Group A urinary bladders were transected cranial to the ureteral papillae to create a closed bladder vesicle which was concomitantly omentalized. Group B underwent omentalization two weeks prior to vesicle creation. Based on Group A and B results, Group C underwent neoureterocystostomy and omentalization followed by neoreservoir formation and tube cystostomy 2 weeks later. Serial ultrasounds and histopathology confirmed adequate omental neovascularization in Groups B and C with continent Group C neoreservoirs maintained for 2 months. Some pylectasia and ureteral dilation was documented in all Group C dogs at variable timepoints. Progressive hydroureteronephrosis developed in 2/6 kidneys. Transient azotemia was noted in only 1 Group C dog, although all developed treatable urinary tract infections. The sample size is limited, and the efficacy of this technique in providing disease control for UC is unknown. However, this novel option could allow for primary UC resection while providing continence and limiting complications. Postoperative local or systemic adjuvant therapy, ultrasonographic neoreservoir monitoring, and BRAF analysis would be indicated.

Serum artemin is not correlated with sensitivity within dogs with naturally occurring osteoarthritis pain.

Osteoarthritis (OA) pain is associated with peripheral and central sensitization in humans and results in widespread increased sensitivity across the body. Sensitization contributes to the OA-associated pain (OAP) state. We recently identified increased levels of an endogenous neurotrophic factor, artemin (ARTN), in dogs with OAP compared to healthy pain-free controls. Circulating ARTN released from damaged tissues in OA, may play a central role in widespread sensitivity and pain. However, the relationship between ARTN and somatosensory sensitivity remains unknown. The study aimed to assess the relationship between serum ARTN concentrations and measures of sensitivity in dogs with OAP using quantitative sensory testing. We hypothesized that there would be a positive association between circulating ARTN and increased sensitivity to mechanical and thermal stimuli in dogs with OAP. We used linear and logistic regression models to assess the relationship between ARTN, sensitization, and pain within a cohort of 43 dogs with spontaneous OAP. Serum ARTN was not associated with the degree of sensitization within dogs with OAP. Further, across dogs with varying OAP severity, we did not find any association between ARTN, and clinical measures of joint pain and disability. Although a relationship between ARTN and joint pain was not ruled out.

A randomized, prospective, comparative trial of a variable-angle versus fixed-angle endoscope for exploratory thoracoscopy in canine cadavers.

OBJECTIVE: To compare the efficacy of a variable-angle endoscope (VAE) for canine thoracoscopic exploration to a traditional fixed-angle endoscope (FAE). STUDY DESIGN: Randomized, prospective, comparative study. SAMPLE POPULATION: Five fresh canine cadavers. METHODS: Twelve predetermined anatomical locations were labeled after median sternotomy in each cadaveric thorax. Two board-certified veterinary surgeons performed thoracoscopic evaluation of each thorax using a fixed-angle (30°) and a variable-angle (0°-120°) endoscope with and without lungs mechanically ventilated. The order of surgeon, lung ventilation, and endoscope were determined using a randomized block design. Time to visualize each anatomical location was compared for surgeon, endoscope, and lung ventilation status. Primary outcome measures were time to individual anatomical location, total simulated thoracoscopic exploration time, and ability to identify anatomical location within the designated time period. RESULTS: Lung ventilation (difference = 184 seconds, P = .015, 95% CI = 45-342 seconds) and endoscope type (difference = 112 seconds, P = .029; 95% CI = 10-213 seconds) had an effect on the cumulative time for complete thoracoscopic exploration. The VAE shortened the time to identify three of the 12 anatomical locations when controlling for the effects of lung ventilation. Use of the VAE did not improve time to identification for any locations compared to the FAE when lungs were not ventilated. The VAE facilitated significantly shorter cumulative thoracoscopic exploration time compared with the FAE. Failure to identify predetermined locations was more common with the FAE than with the VAE. CONCLUSION: Use of a rigid VAE decreased cumulative thoracoscopic exploration time and provided an alternative to one-lung ventilation for circumventing the visual impediments of lung ventilation. CLINICAL SIGNIFICANCE: This cadaveric study provides evidence that one-lung ventilation and use of a VAE may improve surgeon efficiency during exploratory thoracoscopy.

Results of Open Surgical Repair in Patients With Marfan Syndrome and Distal Aortic Dissection.

BACKGROUND: In patients with Marfan syndrome (MFS), distal aortic dissection can necessitate thoracoabdominal aortic aneurysm (TAAA) repair in survivors of acute DeBakey type I dissection and those with DeBakey type III dissection. We examined outcomes of surgical repair of TAAA in patients with MFS with distal aortic dissection. METHODS: Data were analyzed for 127 consecutive TAAA repairs performed between January 2004 and June 2014 in patients with MFS and distal aortic dissection-DeBakey types I (n = 73) and III (n = 54). The median time from dissection onset to TAAA repair was 5.2 years (interquartile range [IQR]: 2.1 to 9.8 years) for the overall group and was longer in patients with DeBakey I (6.5 years, IQR: 3.5 to 13.9 years) than patients with DeBakey III (2.9 years, IQR: 0.6 to 6.0 years, p < 0.001). Eleven patients (9%) had acute or subacute dissection at the time of repair. Sixty-six patients (52%) underwent Crawford extent II TAAA repair. A composite end point, adverse event, was defined as operative death or permanent stroke, renal failure, paraplegia, or paraparesis. RESULTS: Eight patients had adverse events (6%), including 5 operative deaths (4%). There was no permanent stroke and 1 case each of permanent paraplegia and paraparesis. At discharge, 2 early survivors (2%) had renal failure. Extent II repairs did not have substantially different outcomes from other repairs. CONCLUSIONS: In these patients with MFS with aortic dissection, open TAAA repair incurred reasonable operative risk, but improvements are needed to reduce rates of renal failure. Extent II TAAA repair does not appear to increase operative risk in patients with MFS.

Assessment of cord dorsum potentials from caudal nerves in anesthetized clinically normal adult dogs without or during neuromuscular blockade.

OBJECTIVE: To assess the feasibility of measuring cord dorsum potentials (CDPs) in anesthetized clinically normal dogs after caudal nerve stimulation, determine the intervertebral site of maximum amplitude and best waveform of the CDP, and evaluate the effects of neuromuscular blockade. ANIMALS: 8 male and 4 female dogs (age, 1 to 5 years). PROCEDURES: Dogs were anesthetized, and CDPs were recorded via needles placed on the dorsal lamina at intervertebral spaces L1-2 through L7-S1. Caudal nerves were stimulated with monopolar electrodes inserted laterally to the level of the caudal vertebrae. Dogs were tested without and during neuromuscular blockade induced with atracurium besylate. The CDP latency and amplitude were determined from the largest amplitude tracings. RESULTS: CDPs were recorded in 11 of 12 dogs without neuromuscular blockade and in all dogs during neuromuscular blockade. The CDP was largest and most isolated at the L4-5 intervertebral space (3 dogs) or the L5-6 intervertebral space (9 dogs); this site corresponded to the segment of insertion of the first caudal nerve. Onset latencies ranged from 2.0 to 4.7 milliseconds, and there was no effect of neuromuscular blockade on latencies. Amplitudes of the CDPs were highly variable for both experimental conditions. CONCLUSIONS AND CLINICAL RELEVANCE: CDPs were recorded from all dogs tested in the study; neuromuscular blockade was not critical for successful CDP recording but reduced muscle artifact. This technique may be useful as a tool to assess the caudal nerve roots in dogs suspected of having compressive lumbosacral disease or myelopathies affecting the lumbar intumescence.