Gastrointestinal neoplasms in dogs represent a challenge for the veterinary clinician and surgeon as they are mostly malignant and when the owner notices the primary clinical changes the disease may already be in an advanced stage. Due to the high clinical and histopathological similarity between mesenchymal gastrointestinal neoplasms, it is often impossible to establish the definitive morphological diagnosis using light microscopy alone. In addition, there are only a few articles describing the anatomopathological and immunohistochemical characteristics, which make its complete characterization urgent and relevant in our context in order to assist the veterinary clinician, surgeon, and pathologist in establishing a precise diagnosis of these tumors.

The objective of this study was to investigate whether cleaning surgical materials used to close pelvic flexure enterotomies with a wet sterile gauze will reduce contamination and whether the use of a full thickness appositional suture pattern (F) or a partial thickness inverting (or Cushing) suture pattern (C) would make a difference in the level of contamination. Large colon specimens were assigned to group F or C and divided into subgroups N and G. In group G, a wet sterile gauze was passed over the suture material, another over the instruments, and another over the gloves. In group N, no treatment was applied. The bacterial concentration was measured by optical density (OD) at 24 h. The OD of subgroup CG was lower than that of subgroup CN (P = 0.019). The OD of subgroup FG was lower than that of subgroup FN (P = 0.02). The OD of subgroups CG, CN, FG, and FN was lower than that of the negative control (P < 0.003, P < 0.001, P < 0.001, and P < 0.00). The use of a sterile wet gauze significantly reduced contamination of suture materials. A partial thickness inverting suture pattern did not produce less contamination than a full thickness appositional suture pattern.

To investigate the effects of a xylazine infusion during isoflurane anesthesia on global perfusion parameters and gastrointestinal oxygenation and microperfusion, 8 adult warmblood horses were sedated with xylazine and anesthesia induced with midazolam and ketamine. Horses were mechanically ventilated during anesthesia. After 3 h of stable isoflurane anesthesia (FEIso 1.3 Vol %), a xylazine infusion with 1 mg/kg body weight (BW) per hour was started for 1 h and then stopped. Before, during, and after xylazine infusion, heart rate (HR), arterial blood pressure (MAP), cardiac output (CO), central venous pressure (CVP), and pulmonary artery pressure (PAP) were measured and systemic vascular resistance (SVR) was calculated. Arterial blood gases were taken and oxygen delivery (DO2) and alveolar dead space (VDalv) were calculated. Further intestinal oxygen and microperfusion were measured using white light spectroscopy and laser Doppler flowmetry. Surface probes were placed via median laparotomy on the stomach, the jejunum, and the colon. Wilcoxon rank-sum test was used to compare values over time (P < 0.05). During xylazine infusion, MAP, CVP, PAP, SVR, and VDalv increased significantly, whereas CO, DO2, and intestinal microperfusion decreased. Intestinal oxygenation remained unchanged. All parameters returned to pre-xylazine values within 1 h after stopping xylazine infusion. A xylazine infusion during constant isoflurane anesthesia in horses impairs global and intestinal perfusion without changing tissue oxygenation in normoxic healthy horses. Further studies are necessary, however, to evaluate whether a possible reduction of isoflurane concentration by xylazine infusion will ameliorate these negative effects.

OBJECTIVE To examine effects of continuous rate infusion of lidocaine on transmural neutrophil infiltration in equine intestine subjected to manipulation only and remote to ischemic intestine. ANIMALS 14 healthy horses. PROCEDURES Ventral midline celiotomy was performed (time 0). Mild ischemia was induced in segments of jejunum and large colon. A 1-m segment of jejunum was manipulated by massaging the jejunal wall 10 times. Horses received lidocaine (n = 7) or saline (0.9% NaCl) solution (7) throughout anesthesia. Biopsy specimens were collected and used to assess tissue injury, neutrophil influx, cyclooxygenase expression, and hypoxia-inducible factor 1α (HIF-1α) expression at 0, 1, and 4 hours after manipulation and ischemia. Transepithelial resistance (TER) and mannitol flux were measured by use of Ussing chambers. RESULTS Lidocaine did not consistently decrease neutrophil infiltration in ischemic, manipulated, or control tissues at 4 hours. Lidocaine significantly reduced circular muscle and overall scores for cyclooxygenase-2 expression in manipulated tissues. Manipulated tissues had significantly less HIF-1α expression at 4 hours than did control tissues. Mucosa from manipulated and control segments obtained at 4 hours had lower TER and greater mannitol flux than did control tissues at 0 hours. Lidocaine did not significantly decrease calprotectin expression. Severity of neutrophil infiltration was similar in control, ischemic, and manipulated tissues at 4 hours. CONCLUSIONS AND CLINICAL RELEVANCE Manipulated jejunum did not have a significantly greater increase in neutrophil infiltration, compared with 4-hour control (nonmanipulated) jejunum remote to sites of manipulation, ischemia, and reperfusion. Lidocaine did not consistently reduce neutrophil infiltration in jejunum.

OBJECTIVE To determine the plasma pharmacokinetics and safety of 1% diclofenac sodium cream applied topically to neonatal foals every 12 hours for 7 days. ANIMALS Twelve 2- to 14-day old healthy Arabian and Arabian-pony cross neonatal foals. PROCEDURES A 1.27-cm strip of cream containing 7.3 mg of diclofenac sodium (n = 6 foals) or an equivalent amount of placebo cream (6 foals) was applied topically to a 5-cm square of shaved skin over the anterolateral aspect of the left tarsometatarsal region every 12 hours for 7 days. Physical examination, CBC, serum biochemistry, urinalysis, gastric endoscopy, and ultrasonographic examination of the kidneys and right dorsal colon were performed before and after cream application. Venous blood samples were collected at predefined intervals following application of the diclofenac cream, and plasma diclofenac concentrations were determined by liquid chromatography–mass spectrometry. RESULTS No foal developed any adverse effects attributed to diclofenac application, and no significant differences in values of evaluated variables were identified between treatment groups. Plasma diclofenac concentrations peaked rapidly following application of the diclofenac cream, reaching a maximum of < 1 ng/mL within 2 hours, and declined rapidly after application ceased. CONCLUSIONS AND CLINICAL RELEVANCE Topical application of the 1% diclofenac sodium cream to foals as described appeared safe, and low plasma concentrations of diclofenac suggested minimal systemic absorption. Practitioners may consider use of this medication to treat focal areas of pain and inflammation in neonatal foals.

OBJECTIVE To evaluate effects of laparoscopic-assisted incisional gastropexy (LAIG) on gastric motility in dogs by use of a wireless motility device (WMD). ANIMALS 10 healthy client-owned large or giant-breed dogs. PROCEDURES 10 dogs owned by clients interested in prophylactic LAIG were enrolled. To determine effects of LAIG on gastrointestinal motility in dogs during the nonfed state, each dog was evaluated by use of a noninvasive WMD before and > 4 weeks after LAIG. All dogs underwent LAIG, with or without concurrent elective gonadectomy. Data obtained before and after LAIG were analyzed by use of proprietary software to determine the gastric emptying time, small bowel transit time, large bowel transit time, whole bowel transit time, and motility index. RESULTS No changes in variables were detected between measurements obtained before and after prophylactic LAIG. CONCLUSIONS AND CLINICAL RELEVANCE In this study, prophylactic LAIG did not have an effect on gastrointestinal motility. The WMD was tolerated well by all dogs and appeared to be a safe and effective method for evaluating gastrointestinal motility in this population of dogs.