Improved predictability is needed for calculators used to preoperatively determine the etiology of splenic masses in dogs: an external validation study of the HeLP score and T-STAT.

OBJECTIVE: To assess the predictability of the hemangiosarcoma likelihood prediction (HeLP) score and the Tufts Splenic Tumor Assessment Tool (T-STAT) for hemangiosarcoma and malignancy, respectively. ANIMALS: 261 dogs undergoing splenectomy for a splenic mass. METHODS: Medical records were retrospectively reviewed; variables for the HeLP score and T-STAT were collected, and scores were assigned. Area under the curve (AUC) was calculated for each score. RESULTS: The HeLP score included 141 dogs; hemangiosarcoma was diagnosed in 87 (61.7%) dogs. The median cumulative HeLP score was 51 (range, 17 to 82; IQR, 39 to 58) for dogs with hemangiosarcoma and 28 (range, 0 to 70; IQR, 17 to 41) for dogs without hemangiosarcoma. The categorical HeLP score was low (28; 32.2%), medium (31; 35.6%), and high (28; 32.2%) for dogs with hemangiosarcoma and was low (41; 75.9%), medium (9; 16.7%), and high (4; 7.4%) for dogs without hemangiosarcoma. The AUC of the cumulative and categorical HeLP scores for diagnosis of hemangiosarcoma were 0.79 (95% CI, 0.71 to 0.86) and 0.73 (95% CI, 0.65 to 0.82), respectively. The T-STAT included 181 dogs. Lesions were benign in 95 (52.5%) and malignant in 86 (47.5%) dogs. The median T-STAT score was 62% (range, 5% to 98%; IQR, 36% to 77%) for dogs with malignant lesions and 38% (range, 5% to 91%; IQR, 24% to 59%) for dogs with benign lesions. The T-STAT had an AUC of 0.68 (0.60 to 0.76) for diagnosis of malignancy. CLINICAL RELEVANCE: The HeLP score had acceptable performance, and the T-STAT had poor performance for diagnosis prediction. A tool with excellent or outstanding discrimination is needed to more reliably predict the presence of hemangiosarcoma or a malignant lesion preoperatively.

Bupivacaine liposomal injectable suspension does not provide improved pain control in dogs undergoing abdominal surgery.

OBJECTIVE: To evaluate the difference in postoperative pain scores of dogs undergoing abdominal surgery receiving surgical incision infiltration of saline or bupivacaine liposomal injectable suspension (BLIS). ANIMALS: 40 dogs undergoing exploratory laparotomy. METHODS: Dogs were prospectively enrolled and randomized to receive either BLIS or saline surgical incision infiltration. All dogs received 5.3 mg of BLIS/kg or an equal volume of saline infiltrated in the muscle/fascia, subcutaneous tissue, and intradermal layer during closure. All dogs received a standardized postoperative pain management protocol. Pain assessment was performed at select time points postoperatively by blinded observers with an electronic algometer, short version of the Glasgow Composite Measure Pain Scale (GCMPS), and indirect measures of pain, including systolic blood pressure, heart rate, and serum cortisol levels. RESULTS: At day 0, blood pressure was higher in the saline group (149.6 vs 125.8 mm Hg; P = .006). At day 3, GCMPS was lower in the BLIS group (BLIS = 1, saline = 2, P = .027), though both average GCMPS scores were low and only 10 dogs were available for day 3 assessments (6 BLIS and 4 saline). No other differences in algometer readings, GCMPS scores, other measured parameters, or need for rescue analgesia were present between BLIS and saline groups at any time point. There was no difference in postoperative incisional infection rate or complications. CLINICAL RELEVANCE: Use of BLIS for exploratory laparotomy did not provide improved pain control over postoperative opioid administration alone. Patients that received BLIS had no increase in short-term complications.

Acute kidney injury is common in dogs with septic peritonitis and is associated with increased mortality.

OBJECTIVE: To identify the frequency of and risk factors for acute kidney injury (AKI) in dogs undergoing abdominal surgery for septic peritonitis, and to evaluate outcome and kidney-related risk factors for survival to discharge in those dogs. ANIMALS: 77 dogs that underwent abdominal surgery for septic peritonitis. METHODS: Medical records of dogs that underwent surgery for septic peritonitis from 2012 through 2022 were reviewed. Data regarding signalment, clinical and biochemical findings at presentation, blood creatinine concentration throughout hospitalization, surgery characteristics, postoperative monitoring, and outcome were collected. Dogs were classified based on occurrence of AKI and whether they presented with or developed AKI in-hospital. Perioperative risk factors were evaluated, and outcomes were compared with univariable logistic regression. RESULTS: 31 dogs (40.3%) had AKI diagnosed; 18/77 (23.4%) dogs presented with AKI, 11 (61.1%) of which had it postoperatively, and 13/77 (16.9%) dogs developed AKI postoperatively. Significant factors for presenting with AKI included increasing baseline respiratory rate (OR 2.5 for every 10 beats per minute higher), decreasing systolic blood pressure (OR 0.8 for every 10 mm Hg higher), and increasing body condition score (OR 2.2 for every score greater). No significant factors for developing AKI postoperatively were identified after multiple comparisons adjustment. Sixteen dogs (20.8%) did not survive to discharge; 12 (75.0%) had AKI and 4 (25.0%) did not. Dogs with AKI had decreased odds of survival to discharge (OR 0.2). CLINICAL RELEVANCE: AKI was common in dogs with septic peritonitis and was a significant risk factor for survival to discharge. Clinical surveillance of AKI is critical in this population.

Effect of gabapentin on ambulatory, direct, systemic arterial blood pressure in apparently healthy cats in the at-home and in-clinic environments.

OBJECTIVES: Situational increases in blood pressure (BP) frequently confound the accurate diagnosis of pathological systemic hypertension in cats. The objective of this study was to investigate the effect of gabapentin on direct, ambulatory systolic arterial BP (SBP) in cats in at-home and in-clinic environments. METHODS: Six adult purpose-bred cats with surgically implanted femoral artery telemetric BP-sensing catheters were administered 100 mg of gabapentin or a placebo orally in two randomized, masked, crossover study phases. In the first, direct BP was measured continuously in undisturbed cats for 24 h before (at-home baseline) and 4 h after administration of study drug. The mean SBP after administration of the drug was compared between treatments. In the second study period, cats were administered gabapentin or placebo 90 mins before transport to a clinic, where direct BP was measured continuously during a simulated veterinary visit that included an indirect BP measurement session. Changes in mean direct SBP relative to the 24-h at-home pre-treatment period were calculated for each of one waiting room and two examination-room periods, and compared between treatments. Concurrent in-clinic direct and indirect SBP measurements were compared within-cat. Data were compared using linear mixed models. RESULTS: Direct SBP data from one cat were excluded due to implant failure. There were no differences in at-home or in-clinic SBP between treatment groups, with large inter-individual variability. Cats in both treatment groups experienced in-clinic increases in direct SBP relative to at-home baseline (range 11-50 and 10-52 mmHg in placebo- and gabapentin-treated cats, respectively). Across all visits, direct SBP was 15.6 mmHg higher than indirect SBP (P <0.001). No effects of treatment on difference between direct and indirect SBP were identified. CONCLUSIONS AND RELEVANCE: Significant effects of gabapentin on direct SBP were not identified, though a type II error is possible. Situational increases cannot be excluded in gabapentin-treated cats with high SBP.

Perioperative ventricular arrhythmias are increased with hemoperitoneum and are associated with increased mortality in dogs undergoing splenectomy for splenic masses.

OBJECTIVE: To identify risk factors for intra- and postoperative ventricular arrhythmias (VAs) and in-hospital mortality in dogs undergoing splenectomy for splenic masses. ANIMALS: 308 dogs. METHODS: Records from 2010 through 2018 were reviewed for dogs undergoing splenectomy for a splenic mass. Clinical and laboratory findings on admission, diagnostic imaging, anesthesia, surgery and pathology reports, treatment records, and in-hospital mortality were evaluated with logistic regression. RESULTS: VAs occurred in 138 (44.8%) dogs (126/308 [40.9%] postoperative, 51/308 [16.6%] intraoperative, 26/308 [8.4%] preoperative), with 50/308 (16.2%) dogs having more than one type of VA. Increasing heart rate and body weight, decreasing PCV and platelet count, hemoperitoneum, receipt of a transfusion, and diagnosis of hemangiosarcoma were associated with the presence of intra- and postoperative VAs on univariable analysis (all P < .001). On multivariable analysis, hemoperitoneum (P < .001 , < .001), increasing body weight (P = .026, < .001), and increasing heart rate (P = .028, < .001) were significant for intra- and postoperative VAs, respectively. Twenty dogs died (20/308 [6.5%]; 14/138 [10.1%] with VAs, 6/170 [3.5%] without VAs). Intra- and postoperative VAs were associated with in-hospital mortality (P = .009, .025, respectively). CLINICAL RELEVANCE: Perioperative VAs were common and odds of VAs were increased with hemoperitoneum, increasing heart rate, and increasing body weight. Presence of VAs increased the odds of in-hospital mortality. Despite this, the overall in-hospital mortality rate was low (6.5%), indicating a good prognosis for survival of surgery in dogs with splenic masses, regardless of the presence of VAs or hemoperitoneum.

A remnant kidney surgery model in cats induces acute and chronic outcomes that mimic spontaneous chronic kidney disease.

OBJECTIVE: To report acute and chronic outcomes of cats with chronic kidney disease (CKD) induced by a remnant kidney model. ANIMALS: 32 purpose-bred cats (n = 15 female, n = 17 male). PROCEDURES: Cats underwent a 2-stage reduction in renal mass through partial arterial ligation of 1 kidney (day 28) and delayed contralateral nephrectomy (day 0), targeting an 11/12th functional nephrectomy. Acute (days -28 - 29) survival and renal function parameters were compared over time, and the latter were evaluated as predictors for acute mortality. Chronic (days 30 to >1,100) survival, renal function, and morphology were described. RESULTS: Acutely, renal function deteriorated in all cats (mean ± SD baseline and day 28 serum creatinine mean concentration, 1.13 ± 0.23 mg/dL and 3.03 ± 1.20 mg/dL, respectively; P < .001; and GFR, 3.22 mL/min/kg ± 0.12 and 1.21 mL/min/kg ± 0.08, respectively; P < .001). Seven (22%) cats were euthanized after because of clinical signs of uremia after contralateral nephrectomy. Prenephrectomy renal function tests were not significant indicators for survival during this acute phase. Twenty-five cats entered the chronic phase. Ten cats were euthanized at a median of 163 days from nephrectomy because of progressive renal dysfunction. Median survival times were significantly different when stratified by acute kidney injury grade at day 29. Cats in the chronic phase had clinical courses similar to cats with naturally occurring CKD, and most (13/15) were in CKD stage 2. CLINICAL RELEVANCE: The remnant kidney model is effective at reducing kidney function to an extent that mimics important characteristics of spontaneous CKD in cats.

Evaluation of two nephrocystostomy techniques for ureteral bypass in cats.

OBJECTIVE: To describe two techniques for nephrocystostomy (NCT) in cats. STUDY DESIGN: Experimental study. ANIMALS: Twelve, adult, purpose-bred, cats. METHODS: A simple NCT (n = 3) or bladder cuff NCT (n = 9) was performed in the right or left kidneys. For simple NCT, an 8F catheter was placed through the caudal pole into the renal pelvis and the bladder was sutured around the catheter. For bladder cuff NCT, a 6 mm defect was removed from the caudal pole and a cuff of bladder mucosa was advanced and sutured into the renal pelvis. A 10F catheter was placed through the defect into the renal pelvis and the bladder wall was sutured around the catheter. Catheters were removed 41-118 days post-surgery. Computed tomography (CT) was performed 25 days after catheter removal for the simple NCT and 30 (n = 6) and 90 (n = 3) days after catheter removal for bladder cuff NCT. Histological evaluation of the nephrocystostomy site was performed. RESULTS: All simple NCTs became obstructed after catheter removal. All bladder cuff NCTs were patent, and CT revealed contrast flow into the bladder. Hematuria, clot-associated urethral obstruction, catheter dislodgement, and bladder infection occurred variably after surgery. Histological findings consisted of smooth epithelialization of the NCT and degenerative changes in the caudal pole of the kidney. CONCLUSION: Bladder cuff NCT was feasible in normal cats and remained patent for 90 days. Methods to limit nephrostomy track hemorrhage should be investigated. Degenerative changes may be related to vascular impairment from the bladder cuff sutures. CLINICAL SIGNIFICANCE: Complete ureteral bypass was possible in cats using only native tissues.

Retrospective evaluation of surgical treatment of linear and discrete gastrointestinal foreign bodies in cats: 2009-2021.

OBJECTIVES: Gastrointestinal foreign bodies (FBs) are an important cause of emergency surgical intervention in cats, but little information exists in the literature evaluating the risks and outcomes in this species. The study purpose was to describe cases of feline FBs and compare perioperative factors and outcomes between linear foreign body (LFB) and discrete foreign body (DFB) surgery in cats. METHODS: The medical records from the University of Georgia Veterinary Teaching Hospital were searched for cats that had undergone surgery for FB removal between August 2009 and August 2021. Perioperative data were collected and described. Data were compared between cats with an LFB and cats with a DFB. A binomial probability series was used to estimate the likelihood of postoperative septic peritonitis or mortality in an additional cat in the series. RESULTS: A total of 56 cats were included in this study; 38 cats had a DFB and 18 had an LFB. No cats developed postoperative septic peritonitis, and all cats survived. The likelihood of postoperative septic peritonitis or mortality in an additional cat was estimated to be <5.2%. Cats with an LFB were found to have a significantly higher body condition score (P = 0.047), albumin (P = 0.025), American Society of Anesthesiologists status (P = 0.027), surgery length (P <0.001) and total cost of visit (P = 0.006) when compared with cats with a DFB. Cats with LFBs were more likely to develop a surgical site infection (SSI; P = 0.007) and be administered postoperative antibiotics (P = 0.017). CONCLUSIONS AND RELEVANCE: Cats undergoing surgery for gastrointestinal FBs had a low incidence of postoperative complications. Cats with LFBs had longer surgeries and were more likely to develop postoperative SSIs.

Surgical treatment of deep neck infections in 19 dogs.

OBJECTIVE: Describe clinical features, treatment, and outcomes in dogs with deep neck infections. ANIMALS: 19 dogs undergoing surgical treatment of deep neck infections from January 1, 2015, through December 31, 2020. PROCEDURES: Retrospective record review was conducted, with data collected including clinical signs; neutrophil-to-lymphocyte ratio (NLR); diagnostic imaging, surgical, and histopathologic findings; and follow-up. Spearman correlation and Wilcoxon rank sum were used to compare variables to NLR. RESULTS: All dogs had cervical swelling, and 9 were febrile. On CT, a distinct mass or abscess (7/13) or abscessed lymph node (4/13) was common, with contrast enhancement (10/13), fluid tracking (8/13), and displacement of the trachea, pharynx, or larynx (6/13) also frequently seen. Foreign material was suspected on CT for 4 dogs and was identified at surgery or histopathology for 4 dogs, only 1 of which was suspected on CT. Histopathology most commonly revealed pyogranulomatous inflammation (14/15). Increasing NLR was moderately correlated to a decreased duration of clinical signs before presentation (ρ = -0.548; P = .035) and an increased length of hospitalization (ρ = 0.645; P = .009). Bacterial culture was submitted for all dogs, and polymicrobial infections were common (8/19). Broad-spectrum empirical antimicrobials were commonly prescribed. Change in antimicrobial treatment based on culture was uncommon (3/19). All dogs survived to hospital discharge; 18 dogs with long-term follow-up had complete resolution of clinical signs. CLINICAL RELEVANCE: CT was useful to plan for surgery, and surgical treatment resulted in resolution of clinical signs in all dogs with long-term follow-up available. Empirical antimicrobial treatment, such as amoxicillin-clavulanic acid or ampicillin-sulbactam, should be considered.

Risk factors for neonatal mortality prior to hospital discharge in brachycephalic and nonbrachycephalic dogs undergoing cesarean section.

OBJECTIVES: To compare neonatal survival to discharge rates between brachycephalic and nonbrachycephalic dogs undergoing cesarean section (c-section) and identify risk factors for neonatal mortality. STUDY DESIGN: Retrospective study. ANIMALS OR SAMPLE POPULATION: A total of 480 puppies from 90 bitches undergoing 106 c-sections. METHODS: Medical records of c-sections performed between January 2012 and September 2021 were reviewed. Data collected included brachycephalic versus nonbrachycephalic breed, elective versus emergency c-section, litter size (c-section and total [including those born prior to and via c-section]), and neonatal survival to discharge. A generalized linear mixed model (univariable and multivariable) was performed to evaluate variables versus neonatal survival. RESULTS: Overall neonatal survival to discharge was 93.1% (447/480); survival was similar between brachycephalic and nonbrachycephalic breeds (p = .221, 202/213 [94.8%] brachycephalic survival, 245/267 [91.8%] nonbrachycephalic survival). Puppies delivered via elective c-section were more likely to survive compared to emergency c-section (p < .001, 238/240 [99.2%] elective survival, 209/240 [87.1%] emergency survival). Puppies delivered in larger c-section litters were more likely to survive (p < .004) compared to smaller litters. Total litter size had no effect on survival. CONCLUSION: Brachycephalism had no effect on neonatal survival. Puppies delivered via elective c-section were more likely to survive compared to puppies delivered via emergency c-section. CLINICAL SIGNIFICANCE: Outcomes following c-section are similar between brachycephalic and nonbrachycephalic breeds. While it is preferable to encourage selective breeding for bitches that are able to whelp naturally, elective c-section should be considered in bitches at high risk for dystocia to maximize neonatal survival.

Characterization of the intrarenal renin-angiotensin system in cats with naturally occurring chronic kidney disease.

BACKGROUND: The role of the renin-angiotensin-aldosterone system in cats with chronic kidney disease (CKD) is incompletely understood. OBJECTIVE: To characterize components of the intrarenal renin-angiotensin system (RAS) in cats with CKD. ANIMALS: Eleven cats with naturally occurring CKD (CKD group) and 8 healthy control cats. METHODS: Renal tissue samples were evaluated by reverse-transcription polymerase chain reaction for renin, angiotensinogen, angiotensin-converting enzyme (ACE), and angiotensin II type 1 receptor transcript levels, and by liquid chromatography-mass spectrometry for quantification of angiotensin I, II, III, and IV concentrations. Linear mixed models were used to compare gene transcript levels and concentrations of angiotensin peptides between groups. RESULTS: Cats of the CKD group were significantly older (P < .001) and more likely to be neutered (P = .007) than healthy control cats. Kidneys from cats with CKD had significantly higher transcript levels of angiotensinogen (P < .001) and lower transcript levels of ACE (P < .001) than those from control cats. Renal angiotensin I concentrations were increased in CKD compared with control kidneys (P = .001). No other significant differences in renal transcript levels or angiotensin peptide concentrations were noted between groups. CONCLUSION AND CLINICAL IMPORTANCE: The intrarenal RAS might be activated in cats with CKD. Small sample size and differences in age, neuter status, and dietary sodium intake between groups might have limited the ability to identify a significant difference in concentration of renal angiotensin II.

Influence of exposure to microbial ligands, immunosuppressive drugs and chronic kidney disease on endogenous immunomodulatory gene expression in feline adipose-derived mesenchymal stem cells.

OBJECTIVES: Feline autologous mesenchymal stem cells (MSCs) show promise for immunomodulatory activity, but the functional impact of chronic kidney disease (CKD), concurrent immunosuppressive drug administration or infection is unknown. The study objectives compare endogenous cytokine gene expression (interleukin [IL]-6, IL-10, IL-12p40, IL-18 and transforming growth factor beta [TGF-ß]) in adipose-derived MSCs (aMSCs) from cats with and without CKD, following in vitro exposure to microbial ligands and treatment with common immunosuppressive drugs. METHODS: Previously obtained aMSCs, phenotype CD44+, CD90+, CD105+ and MHCII-, from cats with (n = 6) and without (n = 6) CKD were compared via real-time PCR (RT-PCR) for immunomodulatory gene expression. aMSCs were exposed in vitro to lipopolysaccharide (LPS), peptidoglycan or polyinosinic:polycytidylic acid (Poly I:C), simulating bacterial or viral exposure, respectively. aMSCs were also exposed to ciclosporin, dexamethasone or methotrexate. Gene expression was measured using RT-PCR, and Cq was utilized after each run to calculate the delta cycle threshold. RESULTS: aMSCs isolated from healthy and CKD cats showed no significant differences in gene expression in the five measured cytokines. No significant changes in measured gene expression after drug treatment or microbial ligand stimulation were observed between normal or CKD affected cats. Proinflammatory genes (IL-6, IL-12p40 and IL-18) showed altered expression in aMSCs from both groups when compared with the same cells in standard culture after exposure to methotrexate. Poly I:C altered IL-6 and TGF-ß gene expression in aMSCs from both healthy and CKD cats when compared with the same cells in standard culture. CONCLUSIONS AND RELEVANCE: The five genes tested showed no statistical differences between aMSCs from healthy or CKD cats. There was altered cytokine gene expression between the control and treatment groups of both healthy and CKD cats suggesting feline aMSCs have altered function with immunosuppressive treatment or microbial ligand exposure. Although the current clinical relevance of this pilot study comparing brief exposure to select agents in vitro in aMSCs from a small number of cats is unknown, the study highlights a need for continued investigation into the effects of disease and concurrent therapies on use of cell-based therapies in feline patients.

MicroRNAs are differentially expressed in the serum and renal tissues of cats with experimentally induced chronic kidney disease: a preliminary study.

OBJECTIVE: To identify differentially expressed microRNA in the serum and renal tissues of cats with experimentally induced chronic kidney disease (CKD). SAMPLE: Banked renal tissues and serum from 4 cats. PROCEDURES: Cats previously underwent 90-minute unilateral ischemia with delayed contralateral nephrectomy 3 months after ischemia. Tissues were collected from the contralateral kidney at the time of nephrectomy and from the ischemic kidney 6 months after nephrectomy (study end). Serum was collected prior to ischemia (baseline serum) and at study end (end point serum). Total RNA was isolated from tissues and serum, and microRNA sequencing was performed with differential expression analysis between the contralateral and ischemic kidney and baseline and end point serum. RESULTS: 20 microRNAs were differentially expressed between ischemic and contralateral kidneys, and 52 microRNAs were differentially expressed between end point and baseline serum. Five microRNAs were mutually differentially expressed between ischemic and contralateral kidneys and baseline and end point serum, with 4 (mir-21, mir-146, mir-199, and mir-235) having increased expression in both the ischemic kidney and end point serum and 1 (mir-382) having increased expression in the ischemic kidney and decreased expression in end point serum. Predicted target search for these microRNA revealed multiple genes previously shown to be involved in the pathogenesis of feline CKD, including hypoxia-inducible factor-1α, transforming growth factor-ß, hepatocyte growth factor, fibronectin, and vascular endothelial growth factor A. CLINICAL RELEVANCE: MicroRNAs were differentially expressed after CKD induction in this preliminary study. Regulation of renal fibrosis in feline CKD may occur through microRNA regulation of mRNAs of pro- and anti-fibrotic genes.

Dogs ≥ five years of age at the time of congenital extrahepatic portosystemic shunt diagnosis have better long-term outcomes with surgical attenuation than with medical management alone.

OBJECTIVE: To determine the outcome in dogs diagnosed with congenital extrahepatic portosystemic shunts (EHPSS) at ≥ 5 years of age treated with medical management only (M) or with surgical attenuation (S). The hypothesis was that dogs undergoing surgical attenuation would have a longer survival time than dogs undergoing medical management only. ANIMALS: 351 dogs definitively diagnosed with EHPSS at ≥ 5 years of age. PROCEDURES: Medical records from 2009 to 2019 at 16 veterinary teaching hospitals were evaluated. Data collected included signalment, clinical signs at diagnosis, clinicopathologic data, surgical and medical treatments, shunt morphology, clinical signs and medical treatments at 6 to 12 months after diagnosis, and survival time. RESULTS: 351 dogs (M, 119 [33.9%]; S, 232 [66.1%]) were included in the study. Survival time was longer with surgery than medical management (hazard ratio, 4.2; M, 3.4 years; S, 10.9 years). Continued clinical signs at 6 to 12 months after diagnosis were more common with medical management (M, 40% [33/88]; S, 14% [21/155]). Continued medical treatments at 6 to 12 months after diagnosis were more common in the medical management group (M, 78% [69/88]; S, 34% [53/155]). Perioperative mortality rate was 7.3%. CLINICAL RELEVANCE: Dogs diagnosed at ≥ 5 years of age with EHPSS have significantly better survival times and fewer clinical signs with surgical attenuation, compared with medical management. Older dogs have similar surgical mortality rates to dogs of all ages after surgical EHPSS attenuation.

Incidence of and risk factors for surgical site infection following canine limb amputation.

OBJECTIVE: To determine the incidence of and risk factors for surgical site infection (SSI) following canine thoracic and pelvic limb amputations. STUDY DESIGN: Retrospective, multicenter study. ANIMALS: Dogs (n = 248). METHODS: Medical records were reviewed for preoperative, intraoperative, and postoperative variables including indication for amputation, amputation type, method of muscle transection, duration of surgery and anesthesia, and wound classification. Follow up was ≥30 days or until SSI development. Logistic regression and Fisher's exact tests were used to compare SSI incidence to variables of interest. RESULTS: The incidence of SSI was 12.5% for all procedures and 10.9% for clean procedures. Factors increasing odds of SSI were muscle transection with a bipolar vessel sealing device (P = .023 for all procedures, P = .025 for clean procedures), procedure classified as other than clean (P = .003), and indication for amputation of bacterial infection (P = .041) or traumatic injury (P = .003) compared to neoplasia. CONCLUSION: Use of bipolar vessel sealing devices for muscle transection increased the odds of developing an SSI whereas use of electrosurgery and/or sharp transection did not. Dogs with surgical sites that were other than clean, or with bacterial infection and/or traumatic injury were also at increased odds of SSI. CLINICAL SIGNIFICANCE: Use of electrosurgery or sharp transection for muscle transection should be considered rather than use of bipolar vessel sealing devices to decrease odds of SSI in dogs undergoing limb amputation. Further studies across a variety of procedures are needed to validate these findings given the increasing popularity of these devices in veterinary medicine.

Dogs undergoing surgical excision of mast cell tumors are not at increased risk of incisional complications.

OBJECTIVE: To retrospectively compare the incidence of incisional complications in dogs undergoing surgery for mast cell tumors (MCTs) and soft tissue sarcomas (STSs). ANIMALS: 218 dogs. PROCEDURES: Dogs that underwent excision of ≥ 1 MCT, STS, or both from January 2014 to July 2019 and had ≥ 30 days postoperative follow-up were included. Signalment; anesthesia and surgery time; administration of propofol; tumor type, grade, location, and size; intended surgical margins; histologic margins; perioperative radiation, chemotherapy, and corticosteroid and antihistamine (MCT group) treatments; and incisional complications (classified as major or minor) were recorded. Follow-up information was obtained from owners or primary care veterinarians, if needed. Incidence and severity of incisional complications were compared between the MCT and STS groups. Potential risk factors were assessed for associations with incisional complications by simple and multiple logistic regression analysis. RESULTS: The 218 dogs underwent surgery for 293 tumors (209 MCTs and 84 STSs). Complication rates did not differ between MCT (28/209 [13%]) and STS (12/84 [14%]) groups. For the MCT group, incomplete margins (vs complete or narrow), increasing Patnaik tumor grade, and postoperative chemotherapy (yes vs no) were associated with increased odds of incisional complications on simple regression. On multiple logistic regression, postoperative chemotherapy was associated with increased odds of incisional complications for the MCT group and both groups combined. CONCLUSIONS AND CLINICAL RELEVANCE: On the basis of the results, we suggest that chemotherapy be used with caution ≤ 30 days after surgery for dogs with MCTs. Corticosteroid administration was not associated with incisional complications for the MCT group in this study.

Anatomic characterization of the location of the esophageal ostium relative to the rima glottidis on CT in adult Labrador Retrievers.

OBJECTIVE: To characterize the anatomic location of the esophageal ostium relative to the rima glottidis in adult Labrador Retrievers with the use of CT. ANIMALS: 98 CT scans of 75 adult Labrador Retrievers. PROCEDURES: A search of the medical records database identified records of Labrador Retrievers that underwent CT of the head and neck between January 1, 2015, and December 31, 2018. Evaluators, blinded to each other's results, reviewed CT images and measured esophageal area at the level of the rima glottidis. For each dog, the left esophageal percentage (LEP) was calculated as the esophageal area left of the rima glottidis midline divided by the overall esophageal area at that level. Variables (age, sex, patient position, intubation status, and maxillary support during CT) were evaluated for association with LEP. The CT images of dogs that had multiple scans were assessed for within-patient variance. RESULTS: Mean LEP was 56.2 ± 18.1% for all dogs. Only right lateral recumbency was significantly associated with LEP, with a lower LEP for dogs positioned in right lateral recumbency (42.4 ± 12.7%), compared with left lateral (63.0 ± 7.4%) or sternal (57.3 ± 18.8%) recumbency. No association was detected between LEP and other variables assessed. Eleven dogs had multiple CT scans; within-patient variance for LEP was ± 26.6%. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that, although most dogs had an LEP > 50%, the esophageal ostium was fairly centrally located in most dogs and may be more mobile than previously thought. Additional research is warranted to assess this mobility and whether the esophageal ostium location, relative to the larynx, affects the incidence of aspiration pneumonia in dogs undergoing surgical treatment for geriatric-onset laryngeal paralysis and polyneuropathy.

Influence of doxapram and intermittent 10% carbon dioxide inspiration on cardiovascular and laryngeal functions in anesthetized dogs.

OBJECTIVE: To compare the effects of two doses of doxapram intravenous injection and carbon dioxide inhalation on the cardiovascular and laryngeal functions of anesthetized hounds. STUDY DESIGN: Experimental study. ANIMALS: Six healthy adult dogs. METHODS: In a Latin-square design, the mean arterial blood pressure (MABP) and heart rate (HR) were recorded continuously. The inspiratory normalized glottic gap areas (iNGGA) were measured before and after each stimulation with 0.55 mg/kg of doxapram (L-DOX), 2.2 mg/kg of doxapram (H-DOX), or 90 s of inhalation of 10% carbon dioxide in oxygen (I-CO2 ). The stimulations were tested in duplicate or triplicate. Video clips of the laryngeal movement were scored by board-certified surgeons masked to the treatment. RESULTS: The MABP increased with L-DOX and H-DOX up to 81% (both p < .001 compared to I-CO2 ), and persisted during the other stimulations (both p < .001). An intermittent tachycardic effect of up to 79% increase in HR was observed with doxapram. The HR following H-DOX was higher than L-DOX and I-CO2 (both p < .016). Neither hypertension nor tachycardia was observed with I-CO2 . The iNGGA increased with all treatments (p < .001). The iNGGA was greater with H-DOX than L-DOX and I-CO2 (both p < .007). All treatments received higher scores (all p < .001) with acceptable inter- and intra-observers Krippendorff's alphas. CONCLUSION: All treatments were effective respiratory stimulants in anesthetized dogs; however, doxapram caused hypertension and tachycardia. CLINICAL SIGNIFICANCE: Carbon dioxide inhalation might improve arytenoid motion without cardiovascular effects in dogs during clinical airway examinations.

Evaluation of concurrent perineal hernia in adult male dogs presenting with nontraumatic, acquired inguinal hernias.

A possible association between the development of nontraumatic, acquired inguinal hernias (NAIH) and perineal hernias (PH) has been postulated in adult dogs. The objective of this study was to evaluate the frequency of concurrent diagnosis of PH in dogs presented with NAIH and determine potential risk factors for concurrent PH and NAIH. Medical records of adult male dogs presented for NAIH to 4 hospitals between 2007 and 2017 were retrospectively reviewed. Twenty-one dogs with NAIH were included, 8 of which had concurrent PH. There were no significant differences between dogs with and without PH; however, among dogs with both conditions, intact dogs (8.1 ± 1.4 years) were younger than neutered dogs (11.7 ± 1.0 years; P = 0.007). Thirty-eight percent of male dogs presenting for NAIH had concurrent PH, indicating that these conditions commonly occur together. Dogs presenting for NAIH should be carefully evaluated for concurrent PH before surgical intervention.

Évaluation d'hernie périnéale concomitante chez des chiens mâles adultes présentant des hernies inguinales acquises non traumatiques. Une association possible entre le développement d'hernies inguinales acquises non traumatiques (NAIH) et les hernies périnéales (PH) a été postulée chez les chiens adultes. L'objectif de cette étude était d'évaluer la fréquence des diagnostics simultanés d'HP chez les chiens présentés avec NAIH et de déterminer les facteurs de risque potentiels de PH et NAIH concomitantes. Les dossiers médicaux de chiens mâles adultes présentés pour NAIH à quatre hôpitaux entre 2007 et 2017 ont été revus rétrospectivement. Vingt et un chiens atteints de NAIH ont été inclus, dont huit avaient une PH concomitante. Il n'y avait aucune différence significative entre les chiens avec et sans PH; cependant, parmi les chiens atteints des deux conditions, les chiens intacts (8,1 ± 1,4 ans) étaient plus jeunes que les chiens castrés (11,7 ± 1,0 ans; P = 0,007). Trente-huit pour cent des chiens mâles se présentant pour NAIH avaient une PH concomitante, ce qui indique que ces conditions se produisent généralement ensemble. Les chiens présentant un NAIH doivent être soigneusement évalués pour une PH concomitante avant une intervention chirurgicale.(Traduit par Dr Serge Messier).

Analysis of genes associated with proinflammatory and profibrotic pathways upregulated in ischemia-induced chronic kidney disease in cats.

OBJECTIVE: To use RNA sequencing (RNAseq) to characterize renal transcriptional activities of genes associated with proinflammatory and profibrotic pathways in ischemia-induced chronic kidney disease (CKD) in cats. SAMPLES: Banked renal tissues from 6 cats with experimentally induced CKD (renal ischemia [RI] group) and 9 healthy cats (control group). PROCEDURES: Transcriptome analysis with RNAseq, followed by gene ontology and cluster analyses, were performed on banked tissue samples of the right kidneys (control kidneys) from cats in the control group and of both kidneys from cats in the RI group, in which unilateral (right) RI had been induced 6 months before the cats were euthanized and the ischemic kidneys (IKs) and contralateral nonischemic kidneys (CNIKs) were harvested. Results for the IKs, CNIKs, and control kidneys were compared to identify potential differentially expressed genes and overrepresented proinflammatory and profibrotic pathways. RESULTS: Genes from the gene ontology pathways of collagen binding (eg, transforming growth factor-ß1), metalloendopeptidase activity (eg, metalloproteinase [MMP]-7, MMP-9, MMP-11, MMP-13, MMP-16, MMP-23B, and MMP-28), chemokine activity, and T-cell migration were overrepresented as upregulated in tissue samples of the IKs versus control kidneys. Genes associated with the extracellular matrix (eg, TIMP-1, fibulin-1, secreted phosphoprotein-1, matrix Gla protein, and connective tissue growth factor) were upregulated in tissue samples from both the IKs and CNIKs, compared with tissues from the control kidneys. CONCLUSIONS AND CLINICAL RELEVANCE: Unilateral ischemic injury differentially altered gene expression in both kidneys, compared with control kidneys. Fibulin-1, secreted phosphoprotein-1, and matrix Gla protein may be candidate biomarkers of active kidney injury in cats.