Intra-articular stabilisation of the equine cricoarytenoid joint

Reasons for performing study: The success of laryngoplasty is limited by abduction loss in the early post operative period. Objective: To determine the efficacy of polymethylmethacrylate (PMMA) in stabilising the cricoarytenoid joint (CAJ) and reducing the force on the laryngoplasty suture. Hypothesis: Injection into the cricoarytenoid joint resists the forces produced by physiological laryngeal air flows and pressures thereby reducing the force experienced by the laryngoplasty suture. Methods: Ten cadaver larynges were collected at necropsy and PMMA was injected into one CAJ at selected random. Each larynx was subjected to physiological conditions with with constant (static) or cycling (dynamic) flow. The specimens were tested sequentially in each of 4 conditions: 1) bilateral full abduction (Control 1); 2) transection of the suture on the side without PMMA; 3) bilateral abduction achieved by replacing the suture (Control 2); and 4) cutting the suture on the PMMA side. Tracheal pressure and flow and pressure in the flow chamber were recorded using pressure and flow transducers. The strain experienced by each suture during bilateral abduction (Controls 1 and 2) was measured. Statistical comparison of the 4 conditions was performed using a mixed effect model with Tukey's post hoc test for multiple comparisons. The strain gauge data were analysed by paired comparison of the regression slopes. Results: In the static and dynamic states, tracheal pressure increased and tracheal flow decreased when the suture on the non‐cement side was cut (P<0.05). There was no significant difference in any outcome measure between PMMA injected into the CAJ and bilaterally abducted specimens (Controls 1 and 2) for either condition. The rate of increase in strain with increasing translaryngeal pressure was significantly less on the suture with PMMA placed in the CAJ (P = 0.03). Conclusions: These data provide strong evidence that injecting PMMA into the CAJ resists the collapsing effect of physiological airflows and pressures in vitro and reduces the force experienced by the laryngoplasty suture during maximal abduction. Potential relevance: Augmentation of prosthetic laryngoplasty with this technique may reduce arytenoid abduction loss in the early post operative period.     

Comparison of a new blood sampling device with the vacuum tube system for plasma and hematological analyses in healthy dogs

Pediatric devices based on a capillary system may provide an alternative to vacuum tubes for canine blood sampling. The potential advantages are absence of vein collapse, limited blood volume sampled, and improved safety. The aim of this study was to compare routine plasma and hematological variables in seven healthy dogs using both techniques. Five biochemical analytes were measured, and a complete hematological examination and plasma exogenous creatinine clearance test were performed. No clinically relevant difference between the two techniques was observed for any variable or functional test assessed.     

Effects of Diet and Weight Gain on Body Condition Scoring in Thoroughbred Geldings

In the horse, the body condition score (BCS) system to assess subcutaneous fat deposition is a useful tool for making feeding management decisions. The system includes assessing fat deposition at six body areas (neck, withers, shoulders, ribs, loin, and tail head) and was developed in Quarter Horse mares. It has not been tested for use on other breeds or genders, possibly compromising the system's ability to describe fat accretion in other classes of horse. The objective of this study was to examine the ability of the previously developed fat accretion characteristics to describe fat deposition in mature Thoroughbred (TB) geldings. An additional goal was to determine whether fewer body areas could be used. Fifteen mature TB geldings were fed for weight gain over an 8-month period on one of two diets and were independently assessed for BCS on a monthly basis by two judges. BCS was determined by averaging the scores that were assigned to each of the six body areas. Fat accretion characteristics were also recorded. Across both diets, the neck area scored significantly higher than the withers and loin (P < 0.05) throughout the study. A BCS derived only from the body areas of neck, shoulders, ribs, and tailhead was found to accurately predict the six body area−derived mean BCS. The results of this study provide justification for modifications of the BCS system for use in TB geldings and also demonstrated that fewer body areas can be used to accurately predict mean BCS.     

Pituitary-adrenal function in dogs with acute critical illness

OBJECTIVE: To evaluate pituitary-adrenal function in critically ill dogs with sepsis, severe trauma, and gastric dilatation-volvulus (GDV). DESIGN: Cohort study. ANIMALS: 31 ill dogs admitted to an intensive care unit (ICU) at Washington State University or the University of Pennsylvania; all dogs had acute critical illness for < 48 hours prior to admission. PROCEDURES: Baseline and ACTH-stimulated serum cortisol concentrations and baseline plasma ACTH concentrations were assayed for each dog within 24 hours after admission to the ICU. The change in cortisol concentrations (Delta-cortisol) was calculated for each dog. Morbidity and mortality data were recorded for each patient. RESULTS: Overall, 17 of 31 (55%) acutely critically ill dogs had at least 1 biochemical abnormality suggestive of adrenal gland or pituitary gland insufficiency. Only 1 (3%) dog had an exaggerated response to ACTH stimulation. Dogs with Delta-cortisol < or = 83 nmol/L were 5.7 times as likely to be receiving vasopressors as were dogs with Delta-cortisol > 83 nmol/L. No differences were detected among dogs with sepsis, severe trauma, or GDV with respect to mean baseline and ACTH-stimulated serum cortisol concentrations, Delta-cortisol, and baseline plasma ACTH concentrations. CONCLUSIONS AND CLINICAL RELEVANCE: Biochemical abnormalities of the hypothalamic-pituitary-adrenal axis indicative of adrenal gland or pituitary gland insufficiency were common in critically ill dogs, whereas exaggerated responses to ACTH administration were uncommon. Acutely ill dogs with Delta-cortisol < or = 83 nmol/L may be more likely to require vasopressors as part of the treatment plan.     

Evaluation of wraps covering the distal aspect of pelvic limbs for prevention of bacterial strike-through in an ex vivo canine model

Objective— To determine differences in bacterial strike-through for materials commonly used to cover the distal aspect of the pelvic limb during operative site preparation.
Study Design— Randomized block design; ex vivo model.
Animals— Canine cadaveric pelvic limbs (n=40).
Methods— Pelvic limbs (n=40) were randomly assigned to 4 treatment groups: Group 1=Vetrap^™+sterile Coban^™; Group 2=latex glove+Vetrap^™+sterile Coban^™; Group 3=latex glove+Vetrap^™+sterile Coban^™+sterile latex glove+sterile Coban^™; and Group 4=latex glove+Vetrap^™+sterile disposable drape+sterile Coban^™. Limbs were contaminated with a standardized bacterial solution and routinely prepared using the assigned distal leg wrap. Bandages were fluid challenged with a saline (0.9% NaCl) solution-soaked laparotomy sponge for 30 seconds. The wrap surface was sampled for microbial culture before surgical preparation, immediately after, and 60 minutes after applying a sterile leg wrap.
Results— Bacterial growth occurred in all Group 1 cultures, 90% of Group 2 cultures, and none of the Group 3 and 4 cultures, 60 minutes after applying the sterile wrap.
Conclusion— A distal leg wrap of Vetrap^™+sterile Coban^™ is not effective in preventing bacterial strike-through.
Clinical Relevance— If similar results occur in the live animal, then a sterile impermeable barrier must be incorporated into the distal leg wrap to prevent bacterial strike-through.     

Equine adipose-tissue derived mesenchymal stem cells and platelet concentrates: their association in vitro and in vivo

Equine mesenchymal stem cells (MSC) are of particular interest both for basic research and for the therapeutic approach to musculoskeletal diseases in the horse. Their multilineage differentiation potential gives them the capability to contribute to the repair of tendon, ligament and bone damage. MSCs are also considered a promising therapeutic aid in allogeneic cell transplantation, since they show low immunogenicity and immunomodulating functions.Adipose tissue-derived adult equine stem cells (AdMSC) can be isolated, expanded in vitro and then inoculated into the damaged tissue, eventually in the presence of a biological scaffold. Here we report our preliminary experience with adipose-derived mesenchymal stem cells in allogeneic cell-therapy of tendonitis in the horse. MSCs, derived from visceral adipose tissue, were grown in the presence of autologous platelet lysate and characterized for their differentiation and growth potential. Expanded AdMSC were inoculated into the damaged tendon after their dispersion in activated platelet-rich plasma (PRP), a biological scaffold that plays an important role in maintaining cells in defect sites and contributes to tissue healing. Fourteen out of sixteen treated horses showed a functional recovery and were able to return to their normal activity.     

Serum biomarker profiling in cancer studies: a question of standardisation?

Companion animals are exposed to similar environmental conditions and carcinogens as humans. In some animal cancers, there also appears to be the same genetic changes associated as in humans. However, little work has been carried out in cancer biomarker identification in animals. The recent dramatic advances in molecular medicine, genomics, proteomics and translational research will allow biomarker identification, which may provide the best strategies for veterinarians and clinicians to combat disease by early diagnosis and administration of effective treatments. Proteomics may have important applications in cancer diagnosis, prognosis and predictive clinical outcome that could directly change clinical practice by affecting critical elemen‐ts of care and management. This review summarizes the advances in proteomics that has propelled us to this exciting age of clinical proteomics, and highlights the future work that is required for this to become a reality. In this review, we will discuss the available proteomic technologies and their limitations, and highlight the key areas of research and how they have been used to discover cancer biomarkers. The principles described here are equally applicable to human and animal disease, but implementation of ‘omic’ technologies requires stringent guidelines for collection of clinical material, the application of analytical techniques and interpretation of the data.     

The vasovagal tonus index as a prognostic indicator in dogs with dilated cardiomyopathy

Objectives : To investigate the prognostic and diagnostic value of heart rate variability (HRV) using the vasovagal tonus index (VVTI) in dogs suffering from idiopathic dilated cardiomyopathy (DCM). Methods : Electrocardiographic (ECG) recordings of 369 patients presented to a referral centre between 1993 and 2006 were reviewed. Results : VVTI values were calculated from 132 dogs. Lower VVTI values were found in patients in International Small Animal Cardiac Health Council (ISACHC) heart failure (HF) class 2 and 3 compared with class 1. VVTI was found to be positively correlated with survival time (ST) in class 2 and 3 patients. When a cut‐off value of 7·59 for VVTI was used, the test could differentiate patients in ISACHC HF class 1 versus 2 and 3 with a sensitivity of 89 per cent and a specificity of 62·5 per cent. The ST for patients with VVTI values less than 7·59 was significantly lower. Clinical Significance : The VVTI is a useful index, obtained from a standard ECG recording that estimates HRV in dogs and does not require any specific equipment for its calculation. It can be useful as a diagnostic tool to assess the severity of HF and is a useful prognostic tool in dogs with DCM.     

Comparison of alfaxalone and propofol administered as total intravenous anaesthesia for ovariohysterectomy in dogs

ObjectiveTo compare the anaesthetic and cardiopulmonary effects of alfaxalone with propofol when used for total intravenous anaesthesia (TIVA) during ovariohysterectomy in dogs.Study designA prospective non-blinded randomized clinical study.AnimalsFourteen healthy female crossbred bitches, aged 0.5–5 years and weight 16–42 kg.MethodsDogs were premedicated with acepromazine 0.01 mg kg^?1 and morphine 0.4 mg kg^?1. Anaesthesia was induced and maintained with either propofol or alfaxalone to effect for tracheal intubation followed by an infusion of the same agent. Dogs breathed spontaneously via a ‘circle’ circuit, with oxygen supplementation. Cardiopulmonary parameters (respiratory and heart rates, end-tidal carbon dioxide, tidal volume, and invasive blood pressures) were measured continuously and recorded at intervals related to the surgical procedure. Arterial blood samples were analysed for blood gas values. Quality of induction and recovery, and recovery times were determined. Non-parametric data were tested for significant differences between groups using the Mann–Whitney U-test and repeatedly measured data (normally distributed) for significant differences between and within groups by anova.ResultsBoth propofol and alphaxalone injection and subsequent infusions resulted in smooth, rapid induction and satisfactory maintenance of anaesthesia. Doses for induction (mean ± SD) were 5.8 ± 0.30 and 1.9 ± 0.07 mg kg^?1 and for the CRIs, 0.37 ± 0.09 and 0.11 ± 0.01 mg kg^?1 per minute for propofol and alfaxalone respectively. Median (IQR) recovery times were to sternal 45 (33–69) and 60 (46–61) and to standing 74 (69–76) and 90 (85–107) for propofol and alphaxalone respectively. Recovery quality was good. Cardiopulmonary effects did not differ between groups. Hypoventilation occurred in both groups.Conclusions and clinical relevanceFollowing premedication with acepromazine and morphine, both propofol and alphaxalone produce good quality anaesthesia adequate for ovariohysterectomy. Hypoventilation occurs suggesting a need for ventilatory support during prolonged infusion periods with either anaesthetic agent.     

Pharmacokinetics and dose selection of a novel, long-acting transdermal fentanyl solution in healthy laboratory Beagles

A novel, transdermal fentanyl solution (TFS) was developed that delivers sustained concentrations of fentanyl for days following a single application. The pharmacokinetics following a single topical dose was examined. Eighteen adult Beagle dogs were divided into three groups of six dogs (3M, 3F). Each group was administered a single dose of 1.3 (25), 2.6 (50), or 5.2 mg/kg (100 μL/kg) of TFS. The dose was applied to the clipped, ventral abdominal skin using a 1-mL tuberculin syringe. Immediately following dosing, collars were placed on each dog through 72 h to prevent direct licking of the application site. Serial jugular venous blood samples were collected at 0 (predosing), 1, 2, 4, 6, 8, 12, 24, 36, 48, 60, 72, 84, 96, 108, 120, 144, 168, 240, 336, 408, and 504 h after dosing and assayed for plasma fentanyl concentration. Fentanyl was rapidly detected following application with a mean absorption lag time (t(lag) ) of 0.333 h in the 1.3 mg/kg group and 0 in the other two groups. The mean C(max) increased with dose and were 2.28, 2.67, and 4.71 ng/mL in the 1.3, 2.6 and 5.2 mg/kg dose groups, respectively. Mean terminal half-lives were 53.7, 69.6, and 103 h in the 1.3, 2.6, and 5.2 mg/kg dose groups, respectively. The mean AUC(0-LLOQ) from lowest to highest dose groups were 157, 268, and 645 ng·h/mL and were dose proportional with a R(2) value of 0.9818. Adverse reactions were limited to the highest dose group and included sedation (four of six dogs) and decreased food and water intake (one dog). A dose of 2.6 mg/kg (50 μL/kg) is proposed for further development studies based on the lack of adverse events that were observed compared to the 5.2 mg/kg group and a more rapid onset of action and longer duration of action compared to the 1.3 mg/kg group.