Use of near-infrared fluorescence angiography with indocyanine green to evaluate direct cutaneous arteries used for canine axial pattern flaps.

OBJECTIVE: To describe the use of near-infrared angiography (NIRFA) to identify the vascularization of three canine axial pattern flaps (APFs) omocervical (OMO), thoracodorsal (THO), and caudal superficial epigastric (CSE); to establish a vascular fluorescence pattern (VFP) grading system; and to evaluate the effect of NIRFA on surgeon flap dimension planning compared to traditional landmark palpation (LP) and visualization assessments. STUDY DESIGN: Experimental study. ANIMALS: A total of 15 healthy, client-owned dogs. METHODS: Dogs were sedated and flap sites were clipped. LP-based margins were drawn and preinjection images were recorded. Indocyanine green (ICG) was administered and VFP images were recorded. VFP scores were determined by five surgeons. Margin alterations were performed based on NIRFA-ICG images. Altered measurements were compared between LP and NIRFA-ICG images. RESULTS: Vascularization of the CSE flap was most visible with NIRFA with VFP scores 4/4 for 13/15 dogs. Intersurgeon agreement for VFP grades was poorest for THO (ICC = 0.35) and intermediate for OMO (ICC = 0.49) flaps. Surgeons were more likely to adjust dimensions for CSE flaps relative to OMO (OR 17.3, 95% CI: 6.2, 47.8) or THO (25.5; 8.6, 75.7). CONCLUSION: Using a grading system, we demonstrated that the CSE flap was most visible. Surgeons were more likely to adjust the LP-CSE flap margins based on fluorescence patterns and were more likely to rely on LP when visualization scores were low. CLINICAL SIGNIFICANCE: NIRFA has possible applications identifying some direct cutaneous arteries of APFs and their associated angiosomes in real-time. Further investigation is indicated to study NIRFA's potential to improve patient specific APF planning.

Lactate to Albumin Ratio Is Not Predictive of Outcome in Septic Dogs: A Retrospective Case-Control Study.

The objective of this study was to investigate the value of the lactate to albumin ratio (L:A) as a prognostic marker for mortality in septic dogs. A single-center retrospective case-control study based on clinical record review was conducted at an academic teaching hospital. All records were extracted for diagnoses of bacterial sepsis, septic peritonitis, septic shock, or septicemia between February 2012 and October 2021. The study included 143 dogs. The most commonly identified sepsis diagnoses in dogs were septic peritonitis (55%; 78/143), unclassified sepsis (20%), and sepsis secondary to wounds or dermatological conditions (10%; 15/143). Median lactate and albumin for all dogs at presentation were 2.80 mmol/L and 2.6 g/dL, respectively; the median L:A ratio was 1.22. No clinically or statistically significant differences in lactate (P = 0.631), albumin (P = 0.695), or L:A (P = 0.908) were found between survivors and nonsurvivors.

The ARRIVE guidelines 2.0: Updated guidelines for reporting animal research.

Reproducible science requires transparent reporting. The ARRIVE guidelines (Animal Research: Reporting of In Vivo Experiments) were originally developed in 2010 to improve the reporting of animal research. They consist of a checklist of information to include in publications describing in vivo experiments to enable others to scrutinise the work adequately, evaluate its methodological rigour, and reproduce the methods and results. Despite considerable levels of endorsement by funders and journals over the years, adherence to the guidelines has been inconsistent, and the anticipated improvements in the quality of reporting in animal research publications have not been achieved. Here, we introduce ARRIVE 2.0. The guidelines have been updated and information reorganised to facilitate their use in practice. We used a Delphi exercise to prioritise and divide the items of the guidelines into 2 sets, the "ARRIVE Essential 10," which constitutes the minimum requirement, and the "Recommended Set," which describes the research context. This division facilitates improved reporting of animal research by supporting a stepwise approach to implementation. This helps journal editors and reviewers verify that the most important items are being reported in manuscripts. We have also developed the accompanying Explanation and Elaboration (E&E) document, which serves (1) to explain the rationale behind each item in the guidelines, (2) to clarify key concepts, and (3) to provide illustrative examples. We aim, through these changes, to help ensure that researchers, reviewers, and journal editors are better equipped to improve the rigour and transparency of the scientific process and thus reproducibility.

Reporting animal research: Explanation and elaboration for the ARRIVE guidelines 2.0.

Improving the reproducibility of biomedical research is a major challenge. Transparent and accurate reporting is vital to this process; it allows readers to assess the reliability of the findings and repeat or build upon the work of other researchers. The ARRIVE guidelines (Animal Research: Reporting In Vivo Experiments) were developed in 2010 to help authors and journals identify the minimum information necessary to report in publications describing in vivo experiments. Despite widespread endorsement by the scientific community, the impact of ARRIVE on the transparency of reporting in animal research publications has been limited. We have revised the ARRIVE guidelines to update them and facilitate their use in practice. The revised guidelines are published alongside this paper. This explanation and elaboration document was developed as part of the revision. It provides further information about each of the 21 items in ARRIVE 2.0, including the rationale and supporting evidence for their inclusion in the guidelines, elaboration of details to report, and examples of good reporting from the published literature. This document also covers advice and best practice in the design and conduct of animal studies to support researchers in improving standards from the start of the experimental design process through to publication.

The ARRIVE guidelines 2.0: updated guidelines for reporting animal research.

Reproducible science requires transparent reporting. The ARRIVE guidelines (Animal Research: Reporting of In Vivo Experiments) were originally developed in 2010 to improve the reporting of animal research. They consist of a checklist of information to include in publications describing in vivo experiments to enable others to scrutinise the work adequately, evaluate its methodological rigour, and reproduce the methods and results. Despite considerable levels of endorsement by funders and journals over the years, adherence to the guidelines has been inconsistent, and the anticipated improvements in the quality of reporting in animal research publications have not been achieved. Here, we introduce ARRIVE 2.0. The guidelines have been updated and information reorganised to facilitate their use in practice. We used a Delphi exercise to prioritise and divide the items of the guidelines into 2 sets, the 'ARRIVE Essential 10,' which constitutes the minimum requirement, and the 'Recommended Set,' which describes the research context. This division facilitates improved reporting of animal research by supporting a stepwise approach to implementation. This helps journal editors and reviewers verify that the most important items are being reported in manuscripts. We have also developed the accompanying Explanation and Elaboration document, which serves (1) to explain the rationale behind each item in the guidelines, (2) to clarify key concepts, and (3) to provide illustrative examples. We aim, through these changes, to help ensure that researchers, reviewers, and journal editors are better equipped to improve the rigour and transparency of the scientific process and thus reproducibility.

The ARRIVE guidelines 2.0: Updated guidelines for reporting animal research.

Reproducible science requires transparent reporting. The ARRIVE guidelines (Animal Research: Reporting of In Vivo Experiments) were originally developed in 2010 to improve the reporting of animal research. They consist of a checklist of information to include in publications describing in vivo experiments to enable others to scrutinise the work adequately, evaluate its methodological rigour, and reproduce the methods and results. Despite considerable levels of endorsement by funders and journals over the years, adherence to the guidelines has been inconsistent, and the anticipated improvements in the quality of reporting in animal research publications have not been achieved. Here, we introduce ARRIVE 2.0. The guidelines have been updated and information reorganised to facilitate their use in practice. We used a Delphi exercise to prioritise and divide the items of the guidelines into 2 sets, the "ARRIVE Essential 10," which constitutes the minimum requirement, and the "Recommended Set," which describes the research context. This division facilitates improved reporting of animal research by supporting a stepwise approach to implementation. This helps journal editors and reviewers verify that the most important items are being reported in manuscripts. We have also developed the accompanying Explanation and Elaboration document, which serves (1) to explain the rationale behind each item in the guidelines, (2) to clarify key concepts, and (3) to provide illustrative examples. We aim, through these changes, to help ensure that researchers, reviewers, and journal editors are better equipped to improve the rigour and transparency of the scientific process and thus reproducibility.

The ARRIVE guidelines 2.0: Updated guidelines for reporting animal research.

Reproducible science requires transparent reporting. The ARRIVE guidelines (Animal Research: Reporting of In Vivo Experiments) were originally developed in 2010 to improve the reporting of animal research. They consist of a checklist of information to include in publications describing in vivo experiments to enable others to scrutinise the work adequately, evaluate its methodological rigour, and reproduce the methods and results. Despite considerable levels of endorsement by funders and journals over the years, adherence to the guidelines has been inconsistent, and the anticipated improvements in the quality of reporting in animal research publications have not been achieved. Here, we introduce ARRIVE 2.0. The guidelines have been updated and information reorganised to facilitate their use in practice. We used a Delphi exercise to prioritise and divide the items of the guidelines into 2 sets, the "ARRIVE Essential 10," which constitutes the minimum requirement, and the "Recommended Set," which describes the research context. This division facilitates improved reporting of animal research by supporting a stepwise approach to implementation. This helps journal editors and reviewers verify that the most important items are being reported in manuscripts. We have also developed the accompanying Explanation and Elaboration document, which serves (1) to explain the rationale behind each item in the guidelines, (2) to clarify key concepts, and (3) to provide illustrative examples. We aim, through these changes, to help ensure that researchers, reviewers, and journal editors are better equipped to improve the rigour and transparency of the scientific process and thus reproducibility.

When Evidence Goes "Missing in Action": Implications for Patient Management in Cardiac Surgery.

Best-practice clinical decision-making for patient blood management (PBM) and transfusion in cardiac surgery requires high-quality, timely information. However, evidence will be misleading if published information lags too far behind evolving practice, or if trial results are biased, incomplete, or unreported. The result is that providers are deprived of accurate data, and patients will not receive best possible care. Publicly accessible trial registries provide information for structured audits of reporting compliance, and appraisal of evidence attrition and distortion. Trials related to blood management and transfusion in cardiac surgery and those registered in ClinicalTrials.gov were evaluated for relevance, reliability, transparency, timeliness, and prevalence of unreported trial results. Evidence was considered to have "disappeared" if no results were posted to the registry and no related PUBMED publications were available by July 2019. Data were summarized by descriptive statistics. A total of 181 registered trials were surveyed; 52% were prospectively registered. Most commonly reported primary outcomes were laboratory surrogate measures (34%). Patient- and practice-relevant outcomes-mortality/major morbidity (7%), transfusion (27%), and major bleeding (28%)-were less common. Only seven studies posted results to the registry within the mandated 12 months from study completion; median time to posting was 17 (interquartile range [IQR] 13, 37) months. Trial results for 58% were unreported 3-9 years after trial completion. A staggering amount of clinical trial evidence for PBM in cardiac surgery is missing from publicly accessible records and the literature. Investigators must be incentivized to promptly and completely report all results. Penalties for noncompliance are already in place and should be enforced. Simplified information linkage, centralized and routine audit cycles, and prioritization of robust "living" reviews may be more positive motivators. Implementation will require a sea change in the prevailing culture of research reporting, plus coordinated efforts of clinicians, applied statisticians, information technology specialists, and research librarians.

Hydroxocobalamin for the treatment of cardiac surgery-associated vasoplegia: a case series.

PURPOSE: Vasoplegia is a clinical syndrome marked by severe arteriolar vasodilatation, hypotension, and low systemic vascular resistance refractory to multiple vasopressor treatment. We report our experience with hydroxocobalamin (B12) infusion as a potential rescue adjunct for refractory vasoplegia during cardiopulmonary bypass (CPB). METHODS: We performed a retrospective chart review of 33 patients undergoing cardiac surgery between 1 January 2013 and 31 December 2015, who were given intravenous B12 for refractory hypotension during, or immediately following, CPB. We assessed mean arterial pressure (MAP) responses using semi-parametric group-based models (trajectory analysis). Vasopressor use was evaluated by norepinephrine-equivalent rates calculated five minutes prior, and up to 60 min following, B12 administration. RESULTS: Patients were mostly male (82%), had a mean (SD) age of 53 (13) yr, and median (IQR) EuroSCORE mortality index of 9 [4-40]. Four patterns of MAP responses to B12 were identified. In Group 1 ("poor responders") nine of 33 patients (27%) had the highest median [IQR] mortality risk (EuroSCORE 40 [4-52]), lowest mean pre-B12 MAP (50 mmHg), and minimal hemodynamic response in spite of continued vasopressor support. In contrast, Group 2 "responders" (8/33, 24%) showed a brisk MAP response (> 15 mmHg) to B12, sustained for > 60 min post-infusion, with 50% vasopressor reduction. Groups 3 and 4 had the lowest median mortality risk (EuroSCORE 8) and highest pre-B12 MAP (72 mmHg). Although Group 3 patients ("sustainers"; 9/33, 27%) showed a sustained MAP improvement, those in Group 4 ("rebounders"; 7/33, 21%) were characterized by hypertensive overshoot followed by a decrease in MAP. CONCLUSION: These data indicate considerable heterogeneity in patient response to B12, potentially dependent on both patient preoperative condition and non-standardized time of administration. B12 may provide a useful alternative therapy for refractory hypotension and vasoplegia, but controlled clinical trials to assess efficacy are needed.

A Comparison of a New Ultrasound-Based Whole Blood Viscoelastic Test (SEER Sonorheometry) Versus Thromboelastography in Cardiac Surgery.

BACKGROUND: Viscoelastic thromboelastography tests such as TEG™ are now routine for assessing the coagulation status of cardiac surgery patients. We compared TEG™ with a new technology, sonic estimation of elasticity via resonance (SEER) sonorheometry, to compare measures of coagulation dynamics of whole blood and assess its potential for rapid, near-point-of-care monitoring of hemostasis during cardiac surgery. METHODS: Whole blood coagulation assessment of a prospective cohort of 50 cardiac surgery patients was performed using SEER sonorheometry and blood samples collected at 4 time points during cardiac surgery: baseline before anesthetic induction, during cardiopulmonary bypass on rewarming, 10 minutes after heparin reversal by protamine, and on patient transfer to the intensive care unit. Clot strength trajectories (G, measured by TEG™; and clot stiffness measured by SEER sonorheometry) and clot times were assessed by repeated-measures mixed models. Strength of association between the 2 methods (clot stiffness and clot times) was assessed using a modified Bland-Altman method for repeated measures; Deming (orthogonal) regression was used to quantify method concordance (constant and proportional bias). RESULTS: Clot strength/stiffness and clot time measures for both techniques showed similar tracking of trajectories. Strength of association between methods was acceptable (correlations, 0.8-0.9); however, Deming regression detected substantial deviation (bias) between techniques. SEER clot stiffness values averaged approximately 10 hPa higher than corresponding G at all time points. Reaction time (TEG™) was 1 to 2.5 minutes longer than corresponding clot times (SEER). Laboratory times (from sample drop-off to results) were substantially less for SEER sonorheometry (median time, 11-17 minutes) compared with nonautomated kaolin TEG™ (median time, 42 minutes). CONCLUSIONS: Currently, no viscoelastic hemostatic analyzer system can be considered the "gold standard"; therefore, differences observed between TEG™ and SEER are of importance only because they show that the methods are not perfectly substitutable. Measurements of clot stiffness determined by the 2 methods were correlated but not interchangeable. Reasons for discrepancies include the substantial difference in the physical methods of inducing coagulation activation in samples and the mathematical assumptions underlying calculations of G. Future studies will be required to evaluate SEER sonorheometry's abilities to identify bleeding diatheses (sensitivity/specificity) or to develop treatment algorithms based on the new tests.

Hextend-perfluorocarbon cocktail inhibits mean arterial pressure response in a rabbit shock model.

BACKGROUND: Hextend (HEX) is standard of care resuscitation fluid for combat-related traumatic hemorrhage. Because HEX has limited oxygen-carrying capacity, combination therapy with oxygen therapeutics could improve oxygen delivery after hemodynamic shock. We hypothesized that addition of perfluorocarbon (PFC) to HEX would improve hemodynamics and oxygen delivery marker response in a rabbit model of hemorrhagic shock. METHODS: Anesthetized New Zealand rabbits (n = 23) were randomly allocated to resuscitation with fresh whole blood (FWB), HEX, or HEX plus PFC (HEX + PFC) after 60 min of hemorrhagic hypotension. Mean arterial pressure (MAP) was sampled every 2-3 min for 120 min postinfusion; MAP profiles were modeled by a one-compartment pharmacokinetic model to determine peak MAP (Pmax), time to peak MAP (tmax), and postinfusion MAP persistence. Arterial blood was sampled every 15 min to examine pH, blood gases PO2 and pCO2, metabolites lactate and glucose, methemoglobin (metHb), and electrolytes. RESULTS: Compared with FWB and HEX, HEX + PFC administration resulted in delayed peak MAP and less persistent (P < 0.0001) MAP elevation; metHb was significantly elevated (P < 0.0001) compared with FWB and HEX. There were no significant differences in PO2, pCO2, or pH. Glucose, hematocrit, and hemoglobin of both HEX and HEX + PFC were significantly lower relative to FWB. Lactate clearance was modest and transient for all treatments; base deficit was significantly more negative for HEX + PFC. CONCLUSIONS: Addition of PFC to HEX did not improve hemodynamics or acidosis. Further dose- and volume-range studies are required to test efficacy of PFC in combination with HEX for hemorrhagic shock.

Effects of Refined Handling on Reproductive Indices of BALB/cJ and CD-1 IGS Mice.

Current mouse handling methods during cage change procedures can cause stress and potentially compromise animal welfare. Our previous study of breeding C57BL/6J mice found modest increases in pup production and a significant reduction in preweaning litter losses when mice were handled using a tunnel as compared with a tail-lift with padded forceps. The current study evaluated how these 2 handling methods affected reproduction by 2 additional mouse strains, BALB/cJ (a low- to intermediate-fecundity strain) and CD-1 IGS (a high-fecundity stock). We predicted that refined handling would have minimal effects on the high-fecundity line with a satisfactory production rate and greater effects on the low-fecundity line. Handling method (tunnel compared with tail-lift) was randomly assigned to monogamous breeding pairs of mice. Reproductive metrics (litter size at birth and weaning, numbers of litters, litter attrition, between-litter intervals, pup wean- ing weight, and sex ratio) were prospectively monitored for 80 BALB/cJ and 77 CD-1 pairs that were bred continuously for 6 mo. Both strains of mice were highly productive, exceeding previously published breeding data. However, neither strain demonstrated operational or statistically significant differences between handling methods for any reproduction metric. As we detected no negative effects in these 2 strains and the benefits are clear in other strains, refined handling should be considered for all breeding mice.

Effect of hydroxocobalamin on surface oximetry in nonexposed humans.

INTRODUCTION: The newer cyanide antidote, hydroxocobalamin, due to its pigmentation, has been found to cause interferences in some laboratory assays. Co-oximetry may also be affected by hydroxocobalamin, leading to false elevations in hemoglobin concentration, methemoglobin, carboxyhemoglobin, and false decreases in oxyhemoglobin. The Masimo Radical-7 is a medical device that performs noninvasive oximetry and estimates hemoglobin (Hb) concentration and percent carboxyhemoglobin (COHb), methemoglobin (MetHb), and oxyhemoglobin saturation (O2Hb). STUDY OBJECTIVES: The study sought to determine the effect of hydroxocobalamin on noninvasive measurement of hemoglobin indices using the Masimo Radical-7 monitor. METHODS: Seven asymptomatic volunteers who were unexposed to cyanide had baseline heart rate (HR), blood pressure (BP), and oximeter measurements recorded followed by an infusion of five grams of hydroxocobalamin over 15 minutes. The above parameters were subsequently recorded at: 5, 10, 15, 30 and 60 minutes post infusion. Data were analyzed by calculating the area under the curve (AUC) for each variable and comparing the results to expected values by paired t tests. Expected AUC values were calculated by extrapolating baseline values across the entire time period. RESULTS: The mean differences from baseline values with 95% confidence intervals and t tests of mean difference were: SBP: 11 mm Hg (95% CI, 0-22; P = .051); HR: -9 (95% CI, -15 to -3; P = .01); Hb: -0.1 (95% CI, -0.7 to 0.4; P = .57); O2Hb: 0 g/dL (95% CI, -1 to 1; P = .41); COHb: -1 (95% CI, -3 to 1; P = .25); MetHb: -0.2 (95% CI, -0.3 to 0; P = .03). DISCUSSION: After infusion of hydroxocobalamin there was a significant elevation of systolic blood pressure and decrease in heart rate. There were no significant differences in Hb, O2Hb, and COHb. Although percent methemoglobin concentrations were statistically lower, the authors feel this difference is of trivial clinical significance. CONCLUSION: The administration of hydroxocobalamin does not significantly impact noninvasive oximetry.

Using refined methods to pick up mice: A survey benchmarking prevalence & beliefs about tunnel and cup handling.

Refined handling improves laboratory mouse welfare and research outcomes when compared to traditional tail handling, yet implementation does not seem to be widespread. Refined handling includes picking up a mouse using a tunnel or cupped hands. The aim of this study was to determine the current prevalence of and beliefs towards refined handling using the theory of planned behavior. It was predicted that refined handling prevalence is low compared to traditional handling methods, and its implementation is determined by individual and institutional beliefs. Research personnel were recruited via online convenience sampling through email listservs and social media. A total of 261 participants in diverse roles (e.g. veterinarians, managers, caretakers, researchers, etc.) responded primarily from the USA (79%) and academic institutions (61%) Participants were surveyed about their current use, knowledge, and beliefs about refined handling. Quantitative data were analyzed via descriptive statistics and generalised regression. Qualitative data were analyzed by theme. Research personnel reported low levels of refined handling implementation, with only 10% of participants using it exclusively and a median estimate of only 10% of institutional mice being handled with refined methods. Individually, participants had positive attitudes, neutral norms, and positive control beliefs about refined handling. Participants' intention to provide refined handling in the future was strongly associated with their attitudes, norms, and control beliefs (p<0.01). Participants believed barriers included jumpy mice, perceived incompatibility with restraint, lack of time, and other personnel. However, participants also believed refined handling was advantageous to mouse welfare, handling ease, personnel, and research. Although results from this survey indicate that current refined handling prevalence is low in this sample, personnel believe it has important benefits, and future use is associated with their beliefs about the practice. People who believed refined handling was good, felt pressure to use it, and were confident in their use reported higher implementation. Increased refined handling could be encouraged through education on misconceptions, highlighting advantages, and addressing important barriers.

Superficial anatomic landmarks can be used to triangulate the location of canine peripheral lymphocentrums: superficial cervical, axillary, and superficial inguinal.

OBJECTIVE: To utilize the geometry of superficial anatomic landmarks to guide incisional location and orientation for peripheral lymphadenectomy, document deep anatomic landmarks for lymphocentrum identification, and develop novel surgical approaches to the superficial cervical, axillary, and superficial inguinal lymphocentrums in dogs. ANIMALS: 12 canine cadavers. PROCEDURES: 2 cadavers were used for a pilot investigation to determine optimal body positioning, select superficial anatomic landmarks for lymphocentrum identification, and evaluate novel surgical approaches to the 3 lymphocentrums. These lymphocentrums were then dissected in 10 additional cadavers using these novel surgical approaches. Measurements of the distances from lymphocentrum to landmark and between landmarks were obtained for each lymphocentrum. Deep anatomic landmarks were recorded for each dissection. The mean and SD were calculated for each measurement and used to develop geometric guidelines for estimating the location of each lymphocentrum for these surgical approaches. RESULTS: Each peripheral lymphocentrum was found in the same location relative to the respective, predetermined, superficial, anatomic boundaries in all cadavers. Briefly, the superficial landmarks to each lymphocentrum were as follows: (1) superficial cervical: wing of atlas, acromion process of scapula, greater tubercle of humerus; (2) axillary: caudal border of transverse head of superficial pectoral muscle, caudal triceps muscle, ventral midline; and (3) superficial inguinal: origin of pectineus muscle, ipsilateral inguinal mammary gland, ventral midline. The proposed superficial and deep surgical landmarks were identified within every cadaver. The previously undescribed surgical approaches were effective for lymphocentrum identification. CLINICAL RELEVANCE: Anatomic landmarks provided in this study may help reduce surgical time and tissue trauma during peripheral lymphadenectomy in dogs. This study was also the first to describe a surgical approach to the superficial inguinal lymphocentrum and ventral approaches to the superficial cervical and axillary lymphocentrums and provided previously unpublished anatomic landmarks for a lateral approach to the superficial cervical lymphocentrum.

Geometric, landmark-guided technique reduces tissue trauma, surgery time, and subjective difficulty for canine peripheral lymphadenectomies: an educational crossover study.

OBJECTIVE: To compare the effect of a geometric, landmark-guided lymphadenectomy (LL) approach to peripheral lymph nodes (LNs) on successful LN identification, surgical time, tissue trauma, and ease of LN identification compared to standard lymphadenectomy (SL) and methylene blue-guided lymphadenectomy (MBL). SAMPLE: 18 adult, mixed-breed canine cadavers operated on by 7 veterinarians and 5 fourth-year veterinary students between July 23 and October 12, 2022. METHODS: Participants were provided standardized, publicly available materials regarding the anatomy and surgical techniques for SL of 3 peripheral lymphocentrums: superficial cervical, axillary (ALN), and superficial inguinal (SILN). Participants performed the 3 SLs unilaterally on canine cadavers. Thereafter, they were randomly assigned to 2 crossover groups: MBL and LL. All dissections were separated by at least 2 weeks for each participant. Primary outcome measures included successful LN identification, surgical time, tissue trauma scores, and subjective difficulty. RESULTS: Successful LN identification was highest with LL (86%) compared to SL (69%) and MBL (67%). Subjective difficulty scores were reduced with LL for SILN dissections. Tissue trauma scores were reduced when using LL for ALN and SILN compared to MBL and SL. Time to LN identification was reduced for ALN with LL. No significant differences were observed between MBL and SL, or for the superficial cervical dissections. CLINICAL RELEVANCE: Peripheral lymphadenectomies are time consuming and difficult for veterinarians in early stages of surgical training. Little surgical guidance is provided within current literature. Geometric, landmark-guided lymphadenectomies may improve LN identification success and reduce surgical time, tissue trauma, and procedure difficulty, which could encourage their clinical application.

Between two stools: preclinical research, reproducibility, and statistical design of experiments.

Translation of animal-based preclinical research is hampered by poor validity and reproducibility issues. Unfortunately, preclinical research has 'fallen between the stools' of competing study design traditions. Preclinical studies are often characterised by small sample sizes, large variability, and 'problem' data. Although Fisher-type designs with randomisation and blocking are appropriate and have been vigorously promoted, structured statistically-based designs are almost unknown. Traditional analysis methods are commonly misapplied, and basic terminology and principles of inference testing misinterpreted. Problems are compounded by the lack of adequate statistical training for researchers, and failure of statistical educators to account for the unique demands of preclinical research. The solution is a return to the basics: statistical education tailored to non-statistician investigators, with clear communication of statistical concepts, and curricula that address design and data issues specific to preclinical research. Statistics curricula should focus on statistics as process: data sampling and study design before analysis and inference. Properly-designed and analysed experiments are a matter of ethics as much as procedure. Shifting the focus of statistical education from rote hypothesis testing to sound methodology will reduce the numbers of animals wasted in noninformative experiments and increase overall scientific quality and value of published research.

'Invisible actors'-How poor methodology reporting compromises mouse models of oncology: A cross-sectional survey.

The laboratory mouse is a key player in preclinical oncology research. However, emphasis of techniques reporting at the expense of critical animal-related detail compromises research integrity, animal welfare, and, ultimately, the translation potential of mouse-based oncology models. To evaluate current reporting practices, we performed a cross-sectional survey of 400 preclinical oncology studies using mouse solid-tumour models. Articles published in 2020 were selected from 20 journals that specifically endorsed the ARRIVE (Animal Research: Reporting of In Vivo Experiments) preclinical reporting guidelines. We assessed reporting compliance for 22 items in five domains: ethical oversight assurance, animal signalment, husbandry, welfare, and euthanasia. Data were analysed using hierarchical generalised random-intercept models, clustered on journal. Overall, reporting of animal-related items was poor. Median compliance over all categories was 23%. There was little or no association between extent of reporting compliance and journal or journal impact factor. Age, sex, and source were reported most frequently, but verifiable strain information was reported for <10% of studies. Animal husbandry, housing environment, and welfare items were reported by <5% of studies. Fewer than one in four studies reported analgesia use, humane endpoints, or an identifiable method of euthanasia. Of concern was the poor documentation of ethical oversight information. Fewer than one in four provided verifiable approval information, and almost one in ten reported no information, or information that was demonstrably false. Mice are the "invisible actors" in preclinical oncology research. In spite of widespread endorsement of reporting guidelines, adherence to reporting guidelines on the part of authors is poor and journals fail to enforce guideline reporting standards. In particular, the inadequate reporting of key animal-related items severely restricts the utility and translation potential of mouse models, and results in research waste. Both investigators and journals have the ethical responsibility to ensure animals are not wasted in uninformative research.

Effects of non-aversive versus tail-lift handling on breeding productivity in a C57BL/6J mouse colony.

Non-aversive handling is a well-documented refinement measure for improving rodent welfare. Because maternal stress is related to reduced productivity, we hypothesized that welfare benefits associated with non-aversive handling would translate to higher production and fewer litters lost in a laboratory mouse breeding colony. We performed a randomized controlled trial to examine the effects of a standard method of handling (tail-lift with forceps) versus non-aversive handling with transfer tunnels ('tunnel-handled') on breeding performance in 59 C57BL/6J mouse pairs. Intervention assignments could not be concealed from technicians, but were concealed from assessors and data analyst. An operationally significant effect of tunnel-handling (large enough differences to warrant programmatic change) was defined before study initiation as a 5% increase in productivity, or one extra pup over the reproductive lifetime of each pair. Pairs were randomly allocated to handling intervention and cage rack location, and monitored over an entire 6-month breeding cycle. For each group, we measured number of pups born and weaned, and number of entire litters lost prior to weaning. Differences between transfer methods were estimated by two-level hierarchical mixed models adjusted for parental effects and parity. Compared to tail-lift mice, tunnel-handled mice averaged one extra pup per pair born (+1.0; 95% CI 0.9, 1.1; P = 0.41) and weaned (+1.1, 95% CI 0.9, 1.2; P = 0.33). More tunnel-handled pairs successfully weaned all litters produced (13/29 pairs, 45% vs 4/30 pairs, 13%; P = 0.015), averaged fewer litter losses prior to weaning (11/29 pairs [38%] vs 26/30 pairs [87%]; P <0.001), and had a 20% lower risk of recurrent litter loss. The increase in numbers of pups produced and weaned with tunnel handling met threshold requirement for operational significance. These data and projected cost savings persuaded management to incorporate tunnel handling as standard of care across the institution. These data also suggest that overlooked husbandry practices such as cage transfer may be major confounders in studies of mouse models.

Right axis deviation in the canine electrocardiogram for predicting severity of pulmonic stenosis: a retrospective cohort analysis.

OBJECTIVE: To investigate the predictive value of right axis deviation of the mean electrical axis (MEA) in assessing the severity of pulmonic stenosis (PS) in dogs. ANIMALS: Records for 218 client-owned dogs diagnosed between 2014 and 2020 with PS as determined by Doppler echocardiography. PROCEDURES: University of Florida Small Animal Clinic medical records were reviewed, and signalment and clinical risk variables (murmur grade and clinical signs) were extracted. MEA was determined from ECG records by use of leads I and III. Predictive potential of MEA and associated risk factors to diagnose PS severity (mild [< 50 mm Hg], moderate, or severe [> 75 mm Hg]) were assessed by receiver-operating characteristic curve analysis and quantile regression. RESULTS: Records for 88 dogs were eligible for analysis. Greater PS severity was associated with smaller breeds presenting with ECG abnormalities, overt clinical signs, and high-category murmur grades (IV and V). Mean MEA increased with stenosis severity category, with an average of 62° for mild, 113° for moderate, and 157° for severe. Each 10° increase in MEA corresponded to an approximately 5-mm Hg increase in PG. Increasing PS severity was associated with MEA right axis deviation > 100° and the more severe cases (PG > 75 mm Hg) with MEA right axis deviation > -180°. CLINICAL RELEVANCE: Mean electrical axis right axis deviation may be a useful screening metric for dogs with suspected moderate to severe PS.