Simona Cerri

Effect of breed, sex, age and body weight on Echocardiographic Measurements in the Equine Species

Little is known about the effect of various animals signalment variables on echocardiographic reference values in the equine species. This study was performed to evaluate the effect of sex, breed, age and body weight (BW) on echocardiographic measurements in the equine species. Echocardiography was performed on 212 ponies or horses of various breeds, aged from 1 day to 37 years old (mean±SD: 7.8 ± 5.8 years), BW 38-890 kg (mean ± SD: 421 ± 133 kg), and free of cardiac disease. Fifty of those animals aged from 2 months to 35 years old (mean ± SD: 11.6 ± 6.4 years old); BW 77-662 kg (mean ± SD: 436 ± 135 kg) were also examined using the pulsed-wave Doppler mode. Standard two-dimensional and M-mode echocardiography were performed on all animals. Standard pulsed-wave Doppler examination of each cardiac valve was performed on the 50 first examined animals. Data were analysed using a general linear model including the effect of sex, age, breed and BW after logarithmic transformation of the data. Therefore, the same analysis was performed separately on animals aged ≤ 2 years-old and on older animals. All dimensional echocardiographic measurements were significantly affected by BW and most of them were significantly affected by breed, but not by sex. Only the aortic and the pulmonary artery internal diameter were significantly affected by age. None of the Doppler measurements were significantly affected by the tested variables. In conclusion, in the equine species, dimensional echocardiographic reference values should be established using regression equations as a function of BW, which could increase the diagnostic value of this leading technique in equine cardiology. Breed could also have an effect on those measurements.

Traditional and Quantitative Assessment of Acid-Base and Shock Variables in Horses with Atypical Myopathy

BACKGROUND Descriptions of acid-base disturbances in atypical myopathy (AM) are limited. OBJECTIVES Describe and compare traditional and quantitative acid-base abnormalities and cardiovascular shock status in horses with AM at admission. ANIMALS 34 horses with AM, 15 healthy controls. METHODS Retrospective case-control study. Records were searched for shock variables (packed cell volume [PCV], blood urea nitrogen [BUN], heart and respiratory rate) and acid-base variables (venous blood gas analysis, electrolytes, total protein, lactate) on admission. Base excess (BE) of free water (BEfw), chloride (BEcl), total protein (BEtp), and unidentified anions (BEua), anion gap (AG), measured strong ion difference (SIDm), and concentration of total nonvolatile weak acids ([Atot]) were calculated. Acid-base classifications, using simplified strong ion model and traditional approach, and shock grades were assigned. A 2-sample Wilcoxon rank-sum test and Bonferroni correction compared variables in AM cases versus control horses. Significance was P < .05/16 for acid-base and P < .05/5 for shock variables. RESULTS Tachycardia, tachypnea, and normal to increased PCV and BUN were common in AM cases. Respiratory, metabolic acid-base alterations, or both were mainly caused by respiratory alkalosis, lactic acidosis, and SIDm alkalosis, alone or in combination. Evaluated variables (except pH, potassium concentration, total protein, and related calculations) were significantly different (P < .001) between AM cases and control horses. The strong ion model provided a more accurate assessment than the traditional approach and identified mixed derangements. CONCLUSIONS AND CLINICAL IMPORTANCE Acid-base derangements should be evaluated in horses with AM and this preferably with the strong ion model.

ULTRASONOGRAPHIC FINDINGS IN 13 HORSES WITH LYMPHOMA.

Ultrasonography and radiography are commonly used for staging of lymphoma in horses, however there is little published information on imaging characteristics for horses with confirmed disease. The purpose of this retrospective, case series study was to describe ultrasonographic and radiographic findings for a group of horses with a confirmed diagnosis of lymphoma. A total of 13 horses were sampled. Lymphadenopathy (8/13), peritoneal effusion (6/13), splenic (6/13), and hepatic (5/13) lesions were the most frequently identified. The predominant splenic and hepatic ultrasonographic lesions were hypoechoic nodules, organomegaly, and changes in echogenicity. Digestive tract lesions were detected in three horses and these included focal thickening and decreased echogenicity of the small (2/13) and large intestinal (2/13) wall. Thoracic lesions were predominantly pleural effusion (4/13), lymphadenopathy (4/13), and lung parenchymal changes (3/13). Enlarged lymph nodes were detected radiographically (4/13) and/or ultrasonographically (2/13) in the thorax and ultrasonographically in the abdomen (7/13) and in the caudal cervical region (4/13). Findings supported the use of abdominal and thoracic ultrasonography for lymphoma staging in horses. Ultrasound landmarks for localizing cecal and caudal deep cervical lymph nodes were also provided.

Effect of High Pressure-Volume and Low Pressure-Volume Mechanical Ventilation on Plasma Concentrations of Inflammatory Markers in Horses during General Anesthesia

Systemic changes of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), neutrophil elastase (ELT) and myeloperoxidase (MPO) during mechanical ventilation (MV) in horses anaesthetized for surgery are evaluated. Thirty-four client-owned ASA I-II horses randomly received mechanical ventilation (MV) with either a peak inspiratory pressure (PIP) of 30 cm H2O and tidal volume (VT)>10 mL kg-1 (high pressure-volume MV) or PIP of 15 cm H2O and VT ≤ 10 mL kg-1 (low pressure-volume MV) in dorsal or lateral recumbency. Horses were premedicated with acepromazine (0.1 mg kg-1 IM) and xylazine (0.6 mg kg-1 IV), induced with midazolam (0.06 mg kg-1 IV) and ketamine (2.2 mg kg-1 IV) and maintained with isoflurane in oxygen 70% plus ketamine-midazolam infusion (1 and 0.02 mg kg-1 h-1, respectively). Anti-inflammatory drug and antibiotics were administered before surgery. Plasmatic proinflammatory mediator concentrations were estimated by ELISA at the beginning (T0) and after 60 minutes (T1) of MV. Mean plasmatic TNF-α, MPO, and ELT concentrations at T1 were significantly (p<0.05) lower than T0. Mean plasmatic concentration of IL-6 did not significantly change with time. The reduction in plasmatic concentration of proinflammatory mediators at T1 was not linked to ventilation strategy or recumbency. None of the ventilation protocols enhanced systemic inflammatory response during surgery after 1 hour of MV. The anti-inflammatory properties of drugs included in the anaesthesia protocol may have contributed to the overall decreased systemic inflammatory mediator concentrations, despite MV and surgery.

Direct intraperitoneal resuscitation with lidocaine, methylene blue and pentoxiphylline combination does not decreases inflammation after intestinal ischemia-reperfusion injury in rats

PURPOSE To evaluate the effects of an intraperitoneal solution of methylene blue (MB), lidocaine and pentoxyphylline (PTX) on intestinal ischemic and reperfusion injury. METHODS Superior mesenteric artery was isolated and clamped in 36 adult male Sprague Dawley rats. After 60 minutes, clamp was removed and a group received intraperitoneally UNITO solution (PTX 25mg/kg + lidocaine 5mg/kg + MB 2mg/kg), while the other group was treated with warm 0.9% NaCl solution. Rats were euthanized 45 min after drug administration. Lung and bowel were collected for histological evaluation (using Parks score) and determination of myeloperoxidase (MPO) and malondialdehyde (MDA) levels. RESULTS Control samples showed lymphoplasmocytic infiltrate and crypt necrosis of villi. MPO and MDA measurements shown no differences between treated and control groups. CONCLUSION The combination of lidocaine, methylene blue and pentoxyphylline administered intraperitoneally at the studied dose, did not decreased histological lesion scores and biochemical markers levels in intestinal ischemia/reperfusion injury.