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Successful management of equine wounds relies on knowledge of the stages of wound healing, factors that can alter those stages, how healing stages can be manipulated, and adherence to the principles of wound healing. Challenges that complicate wound management include the inability to immobilize and/or confine equine patients, and maintain a clean environment during the critical initial stages of healing. Because of these challenges, the equine practitioner relies heavily on bandaging and external coaptation techniques to successfully treat and manage wounds. The type of bandage used is dictated by the region of the body that is injured., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Distal limb wounds in horses heal substantially different than trunk wounds, commonly resulting in exuberant granulation tissue and exposed and sequestered bone. Surgical intervention of severe rectovaginal lacerations in the mare should be delayed until the tissues have heeled and scar tissue has remodeled. Wounds resulting in severe hemorrhage require appropriate emergent fluid therapy and potentially transfusion therapy., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Osteoarthritis (OA) of the centrodistal (CD) and tarsometatarsal (TMT) joints is a common cause of lameness in horses. Intra-articular diagnostic anaesthesia and/or therapeutic injection are relied upon to help diagnose and treat many horses with OA of these joints., Objectives: The objective of this study was to determine the accuracy of arthrocentesis of the CD and TMT joints using a sample population of equine surgeons and surgery residents., Study Design: Randomised experimental study., Methods: Six operators each injected four CD and four TMT joints in 12 sedated horses. The operators were randomly assigned to inject either the left CD and right TMT or the right CD and left TMT on four randomly assigned horses. The joints were injected with a 4 ml solution of contrast medium (2 ml), sterile saline (1.5 ml) and amikacin (0.5 ml). A minimum of two radiographs of each joint was obtained to evaluate the presence of contrast medium within the target joint., Results: The TMT joint was successfully injected in 23/24 joints (96% accuracy). The CD joint was successfully injected in 10/24 joints (42% accuracy). Communication between the TMT and CD joints was visible in 26% of successful TMT injections. Communication between the CD and TMT joints was visible in 20% of successful CD injections., Main Limitations: Despite specific requests to do so, we were unable to standardise the injection technique across all operators., Conclusions: The accuracy of injecting the TMT and CD joints of sedated horses was 96 and 42%, respectively. The CD joint was frequently missed with contrast medium being placed in the periarticular tissues. These data support the clinical impression of the difficulty of injecting the CD joint and suggests that practitioners should utilise ancillary methods, such as radiographs, to ensure proper needle placement., (© 2017 EVJ Ltd.)

A 21-year-old Thoroughbred gelding with a history of equine pituitary pars intermedia dysfunction (PPID) presented with priapism of 2 days' duration. The horse received a caudal morphine epidural and then underwent corpus cavernosum lavage and phallectomy under general anesthesia. The patient's recovery featured multiple unsuccessful attempts to stand and his respiratory distress persisted for several hours until he acutely developed severe colic and was euthanized. Necropsy findings revealed a pituitary adenoma of the pars intermedia, bilateral adrenal cortical hyperplasia, and diaphragmatic herniation. This report suggests that horses with PPID may present a greater risk for diaphragmatic hernia under general anesthesia or during procedures placing stress on the diaphragm, including anesthetic recovery.

Objective: To compare the effects of 2 approaches and 2 injection volumes on diffusion of mepivacaine hydrochloride for local analgesia of the deep branch of the lateral plantar nerve (DBLPN) in horses., Design: Experimental study., Animals: 16 adult horses., Procedures: Either 2 mL (low volume) or 8 mL (high volume) of mepivacaine hydrochloride-iohexol (50:50 mixture) was injected by means of 1 of 2 techniques to produce analgesia of the DBLPN. For technique 1, the needle was inserted 15 mm distal to the head of the fourth metatarsal bone and directed perpendicular to the limb. For technique 2, the needle was inserted 20 mm distal to the head of the fourth metatarsal bone and was directed in a proximodorsal direction. Lateromedial radiographs were obtained before and 5, 15, 30, and 60 minutes after injection. Radiographs were evaluated to determine the proximal and distal extent of diffusion of the contrast solution and presumably anesthetic agent and whether contrast agent appeared to be present in the tarsal sheath or tarsometatarsal joint., Results: A high degree of variability in contrast solution diffusion was noted among injections. High-volume injections diffused significantly further proximally and distally than did low-volume injections. Contrast agent was documented within the tarsal sheath in 5 of 32 (16%) injections and within the tarsometatarsal joint in 2 of 32 (6%) injections. No significant difference was found for risk of inadvertent tarsal sheath or tarsometatarsal joint injection between the 2 techniques or the 2 volumes of anesthetic used. Mepivacaine diffused significantly further distally with technique 1 than with technique 2 but diffused significantly further proximally with technique 2 than with technique 1. For both techniques, diffusion in the distal but not the proximal direction significantly increased over time., Conclusions and Clinical Relevance: Results indicated that the proximal and distal diffusion of the mepivacaine-iohexol solution was quite variable following either DBLPN nerve block technique.

Objective: To determine the clinical signs, treatment, and prognosis for horses with impaction of the cranial aspect of the base of the cecum (cecal cupula)., Design: Retrospective observational case series., Animals: 7 horses with colic attributed to cecal cupula impaction., Procedures: Medical records were reviewed and horses that underwent exploratory celiotomy from 2000 through 2010 were identified. Horses with cecal cupula impaction and without other abdominal problems to which colic could be attributed were selected for inclusion in the study. Information regarding history, clinical findings, diagnostic testing, surgical findings and treatments, and treatments and complications after surgery was recorded. Rate of survival of horses to discharge from the hospital was determined. Long-term follow-up information was obtained with telephone questionnaires., Results: Cecal cupula impaction without other cecal abnormalities was identified in 7 horses during exploratory celiotomy. Although clinical signs varied, horses typically had mild signs of colic and nondiagnostic rectal examination findings but were in systemically stable conditions at the time of the initial evaluation. Typhlotomies were performed and impactions were resolved by means of lavage and evacuation. All horses survived to discharge from the hospital and lived ≥ 2 years after surgery., Conclusions and Clinical Relevance: Results of this study suggested cecal cupula impaction was a novel type of cecal impaction that was uncommon. Impactions did not involve the cecal body or apex and hypertrophy of the cecal wall was not grossly detected. Impactions were successfully treated with typhlotomy, lavage, and evacuation. Horses had a good prognosis after surgical treatment.

Radiographic evaluation of a horse's foot gives tremendous insight into the relationship between the structures within the foot and between the foot and distal limb. The information gained from a radiographic study is highly dependent on the quality of the radiographs. A systematic approach should be taken when planning a radiographic study of the foot. Taking the time to examine the foot and prepare it properly will avoid the need, risk, and expense of repeating images and will improve the quality and therefore the interpretation of your radiographic images. When evaluating the foot for podiatry reasons, it is crucial that the positioning of the patient, foot, and x-ray beam be flawless., (Published by Elsevier Inc.)

Objectives: To compare in vitro physical and mechanical characteristics of 1-layer and 2-layer end-to-end jejunoileostomy., Study Design: In vitro experimental study., Animals: Adult horses (n = 6)., Methods: Harvested equine jejunum and ileum was used to create 1- and 2-layer end-to-end jejunoileostomy specimens. Construction time, bursting pressure, and relative lumen diameter (anastomosis diameter expressed as a percentage of the lumen diameter of adjacent jejunum and ileum) were compared. Construction time and relative lumen diameters were compared using a paired t-test. Bursting pressure for anastomoses and control jejunal segments were compared using a repeated-measure ANOVA. Statistical significance was set at P < .05., Results: Mean (± SEM) construct completion times were shorter for 1 layer (21 ± 0.91 minutes) than 2 layers (26.71 ± 1.16 minutes; P = .005). Relative lumen diameters (percentage of jejunal diameter) were larger for 1 layer (77.67 ± 4.46%) than for 2 layers (69.37 ± 2.8%; P = .035). There were no significant differences in bursting pressures between the 2 groups and the control jejunum (P =.155) or relative lumen diameters (percentage of ileal diameter; P =.118)., Conclusions: One-layer jejunoileostomy can be created in a shorter time and maintain a larger anastomosis luminal diameter without compromising maximum bursting pressure when compared to 2-layer jejunoileostomy., (Copyright 2012 by The American College of Veterinary Surgeons.)

This trial was conducted to determine the effect of the addition of 2 or 4% oleic acid to an hydrogenated fat coating applied to an experimental supplement with 55 or 58% lysine sulfate on ruminal escape and intestinal absorption of Lys. Two lactating Holstein cows (103 d in milk and 45.1 kg/d of milk) previously fitted with ruminal and duodenal cannulas were individually housed and fed a corn silage-based ration. In situ and mobile bag techniques were utilized to evaluate the 4 test products. Twenty bags of each product were incubated for 16 h in each cow to determine ruminal escape. After ruminal incubation, products were repackaged, soaked in pepsin/HCl solution for 2 h, inserted into the duodenum, and subsequently collected in the feces. The percentage of dry matter and fat escaping the rumen decreased as oleic acid increased from 2 to 4% or as the proportion of supplemental Lys increased. An interaction was observed because of a greater reduction of N and Lys escaping ruminal fermentation and flowing to the small intestine for the product with 58% supplemental Lys and 4% oleic acid compared with the other products. No differences were observed in intestinal digestibility of dry matter, N, Lys, or fat or in the amount of Lys digested in the small intestine. Increasing the proportion of oleic acid in the coating applied to supplemental Lys increased ruminal degradation. The extent of the degradation increased as the proportion of Lys in the product increased., (Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

Case Description: A 7-year-old Quarter Horse gelding was evaluated because of sudden onset of severe left forelimb lameness of 4 days' duration., Clinical Findings: Clinical evaluation and diagnostic perineural analgesia localized the lameness to the distal portion of the left forelimb. Radiography revealed a transverse fracture of the distal phalanx of the left forelimb., Treatment and Outcome: The horse was treated conservatively with stall rest and stabilization of the hoof with fiberglass cast material and an elevated heel support. These treatments improved the lameness considerably. Over the following 4 months, the horse was exercised at an increasing level; external coaptation of the hoof was removed, and the horse was gradually shod in a flat shoe. At 6 months after injury, the horse had no signs of lameness when working at its previous performance level, but it was euthanized for reasons unrelated to orthopedic disease. Radiographically, the fracture was unapparent; however, results of magnetic resonance imaging and histologic examination of the cadaveric limb confirmed the presence of tissue changes consistent with a healing fracture., Clinical Relevance: Conservative management of transverse fractures of the distal phalanx of a forelimb may be effective and enable affected horses to be returned to their intended use.

Forty Holstein cows were used in an 8-wk randomized trial to evaluate the effects of feeding combinations of forages with improved fiber digestibility on performance during early lactation. Treatments were arranged as a 2 x 2 factorial to include silage from normal (NCS) or brown midrib (BMR) corn silage with or without 10% Tifton 85 bermudagrass hay (T85). In a simultaneous digestion trial, degradation and passage kinetics and ruminal fermentation parameters were evaluated in a 4 x 4 Latin square design trial using late-lactation Holstein cows fitted with ruminal cannulas. Dry matter intake (DMI) and neutral detergent fiber (NDF) intake were greater with BMR than with NCS; however, milk yield and composition were similar among corn silage types. Inclusion of T85 reduced milk yield but supported higher milk fat percentage, resulting in similar yields of energy-corrected milk. Blood glucose concentrations were higher for BMR compared with NCS, and inclusion of T85 increased blood urea N concentrations. Treatments did not alter liquid or solid phase passage rates or rumen turnover. Corn silage type did not affect ruminal pH or volatile fatty acid concentrations, but inclusion of T85 increased pH and molar proportion of acetate but decreased butyrate. Molar proportions of propionate were greater for NCS and T85 compared with BMR and T85, resulting in an interaction. Results of this trial indicate that combinations of forages with improved fiber digestibility can be used to support intake and performance of cows during early lactation., (Copyright 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

Objective: To investigate the impact of a change in body position on blood gases and arterial blood pressures in foals anesthetized with guaifenesin, ketamine, and xylazine., Study Design: Prospective, randomized experimental study., Animals: Twelve Quarter Horse foals, age of 5.4 +/-0.9 months and weighing 222 +/- 48 kg., Methods: Foals were anesthetized with guaifenesin, ketamine, and xylazine for 40 minutes in lateral recumbency and then assigned to a change in lateral recumbency after hoisting (Group 1, n = 6), or no change (Group 2, n = 6). Oxygen 15 L minute(-1) was insufflated into the endotracheal tube throughout anesthesia. Arterial blood pressure, heart rate, respiratory rate (f(R)), inspired fraction of oxygen (FIO(2)), and end-tidal carbon dioxide (PE'CO(2)) were measured every 5 minutes. Arterial pH and blood gases [arterial partial pressure of oxygen (PaO(2)), arterial partial pressure of carbon dioxide (PaCO(2))] were measured at 10, 30, and 40 minutes after induction, and 5 minutes after hoisting. Alveolar dead space ventilation and PaO(2)/FIO(2) were calculated. Two repeated measures models were used. All hypothesis tests were two-sided and significance level was alpha = 0.05. All values are presented as least square means +/- SE., Results: Values at time-matched points from the two groups were not significantly different so they were combined. Arterial partial pressure of oxygen decreased significantly from 149 +/- 14.4 mmHg before hoisting to 92 +/- 11.6 mmHg after hoisting (p = 0.0013). The PaO(2)/FIO(2) ratio decreased from 275 +/- 30 to 175 +/- 24 (p = 0.0055). End-tidal carbon dioxide decreased significantly from 48.7 +/- 1.6 to 44.5 +/- 1.2 mmHg (p = 0.021). Arterial partial pressure of carbon dioxide, blood pressures and heart rates measured 5 minutes after hoisting were not different from measurements obtained before hoisting., Conclusion and Clinical Relevance: Hoisting decreased PaO(2) in anesthetized healthy foals. Administration of supplemental oxygen is recommended to counter the decrease in oxygenation and PaO(2) measurement is necessary to detect early changes.

Objective: To compare a double-layer inverting anastomosis with a single-layer appositional anastomosis, coated with either 1% sodium carboxymethylcellulose (SCMC) or 0.4% sodium hyaluronate (HA) solutions, in the small intestine of horses with respect to anastomotic healing and adhesion formation., Animals: 18 adult horses., Procedure: Midline celiotomy and end-to-end jejunal anastomoses were performed. In control group horses (n = 6), a double-layer inverting anastomosis coated with sterile lactated Ringer's solution was performed. In treatment group horses, a single-layer appositional anastomosis was performed that was coated with 1% carboxymethylcellulose solution (SAA + SCMC group horses, 6) or 0.4% hyaluronate solution (SAA + HA group horses, 6). An additional 500 mL of the respective treatment solution was applied to the jejunal serosal surface, and 2 jejunal serosal abrasion sites were created. Horses were euthanatized 10 days after surgery. Anastomoses and abdominal adhesions were evaluated grossly. Anastomotic healing was evaluated on the basis of bursting wall tension., Results: Bursting wall tension was significantly greater in SAA + SCMC group horses, compared with control group horses. All intestinal segments failed at a point distant to the anastomosis. Significantly fewer adhesions were found at the abrasion sites of SAA + HA group horses, compared with control group horses. No differences were found in adhesion formation at the anastomotic sites among groups., Conclusions and Clinical Relevance: Coating a single-layer appositional jejunal anastomosis with SCMC or HA solutions does not adversely affect anastomotic healing. Application of 0.4% HA solution to the serosal surface of the jejunum significantly decreases the incidence of experimentally induced intra-abdominal adhesion formation in horses.

As with many aspects of clinical medicine, there is yet to be a single or definitive cure for postoperative adhesion formation. Current methods of prevention target risk factors predisposing horses to adhesion formation. Systemic pharmacologic therapies, such as antimicrobials, nonsteroidal anti-inflammatory drugs, Salmonella antiserum, and hyperimmune plasma, help to reduce abdominal inflammation and minimize the effects of endotoxemia. Intra-abdominal or systemic heparin aids in enhancing peritoneal fibrinolysis. Prokinetic therapy promotes early postoperative return of intestinal motility, minimizing the propensity for adhesion formation between apposing adynamic segments of intestine. Mechanical separation of potentially adhesiogenic serosal and peritoneal surfaces is commonly achieved with use of abdominal lavage, protective coating solutions, and barrier membranes. Ongoing and future research is directed toward a better understanding of the local effects of intestinal trauma and the corresponding response of the fibrinolytic system. Recognition of horses at high risk for adhesion formation helps to guide the equine surgeon to an appropriate perioperative and intraoperative plan for adhesion prevention, including good surgical technique and a combination of adjunct therapies.

Objective: To compare the outcomes of double-layer inverting anastomosis (DIA), single-layer anastomosis (SLA), and single-layer anastomosis combined with a hyaluronate membrane (SLA+HA-membrane) with respect to stomal diameter, adhesion formation, surgery time, and anastomotic healing in horses., Animals: 18 adult horses., Procedure: Midline celiotomy and end-to-end anastomoses were performed. In control horses (n = 6), DIA was performed; in treated horses, SLA was performed (6) or SLA+HA-membrane was performed (6). Horses were euthanatized 21 days after surgery. Abdominal adhesions were evaluated grossly and histologically. Stomal diameters were measured ultrasonographically and compared with adjacent luminal diameters. Anastomotic healing was evaluated histologically for fibrosis and inflammation, tissue alignment, and inversion. Surgery times were recorded for the anastomotic procedure and compared among groups., Results: There were significantly more adhesions in the SLA group, compared with the DIA and SLA+HA-membrane groups. Reduction in stomal diameters in the DIA group was significantly greater than the SLA and SLA+HA-membrane groups. Surgery times for the DIA group were significantly greater than the SLA and SLA+HA-membrane groups. Histologic findings of fibrosis, inflammation, and mucosal healing were similar among groups. There was significant tissue inversion in the DIA group, compared with the 2 treatment groups. Tissue alignment was not different among groups., Conclusions and Clinical Relevance: Use of a SLA+HA-membrane was an effective small intestinal anastomotic technique. This technique was faster to perform and resulted in a larger stomal diameter, compared with the DIA technique and significantly fewer perianastomotic adhesions, compared with the SLA technique.

Numerous techniques for surgical correction of angular limb deformities in horses involving an osteotomy of the affected bone and stabilization with an internal fixation device have been described. However, because the osteotomy typically has to be performed at the level of the physis, leaving little bone between the physis and the nearest joint, stabilizing the osteotomy by use of internal fixation devices may be difficult. In horses with severe chronic angular limb deformities, the amount of soft-tissue contracture may make it impossible to correct the deformity during a single procedure without causing stretch injuries to the adjacent tendons and neurovascular structures. Adjustable external ring fixators incorporating hinged rods on 1 side of the limb and an angular motor assembly on the other may be useful for treatment of severe chronic angular limb deformities in younger equids, because they allow for gradual correction of the deformity.