Laparoscopic intestinal exploration and full-thickness intestinal biopsy in standing horses: a pilot study

Approach to Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) in the horse encompasses a group of infiltrative gastrointestinal disorders resulting in malabsorption, maldigestion, weight loss, colic, and sometimes diarrhea. The type of IBD can be classified as granulomatous, lymphocytic-plasmacytic, or eosinophilic enterocolitis. The diagnosis of IBD in equids is based on consistent clinical signs and clinicopathologic findings in conjunction with confirmatory histopathology from a gastrointestinal biopsy. Treatment usually consists of a combination of immunosuppressive medications, anthelmintics, and dietary modifications. The prognosis of IBD in horses is variable and dependent on the horse's response to treatment; however, horses can show improvement or resolution of clinical signs.

Ex vivo evaluation of a novel suture loop method for equine intestinal biopsies

OBJECTIVE

To compare a novel suture loop method for intestinal biopsies (SLB) with a two-layer, hand-sutured biopsy (HSB) technique in equine small and large intestines.

STUDY DESIGN

Experimental, randomized, ex vivo study.

ANIMALS

Eight healthy adult horses.

METHODS

The duodenum, aboral jejunum, and ventral and dorsal large colon were harvested after euthanasia and divided into three sections each. The sections were randomized to SLB, HSB, or control (C, no biopsy) groups. Tissue samples were excised after placement of a suture loop formed by a 4S Roeder knot and oversewn with a Cushing pattern using barbed suture (SLB), or a simple continuous pattern oversewn with a Cushing pattern (HSB). Intraluminal diameter was assessed with contrast radiographs; bursting pressure and wall tension were determined using a solid-state sensor after instillation of fluid. Tissue samples were evaluated by a board-certified pathologist.

RESULTS

Tissue samples were full thickness with similar depth and quality (p > .3). Changes in intraluminal diameter did not differ between methods (p > .16). The bursting pressures were higher for controls than biopsied sections (p < .009) but were not different between biopsy methods (p = .998). Bursting wall tension was higher for controls (p < .02) and was similar for both biopsy methods (p = .852).

CONCLUSION

The SLB was equivalent to HSB in strength and effect on intraluminal diameter. The HSB samples were larger and more likely to contain mucosa/villi for histologic diagnosis.

CLINICAL SIGNIFICANCE

The SLB method can be adapted for laparoscopic surgery to obtain both small and large intestinal biopsies. Further investigation is needed before clinical use.

Role of Laparoscopy in Diagnosis and Management of Equine Colic

Laparoscopy can be valuable in the diagnosis and treatment of specific types of colic in horses. Most commonly, it is used for horses with chronic recurrent colic for further diagnosis, such as by taking biopsies or to perform treatment. Laparoscopy is also often used for prevention of colic, for example, by closing the nephrosplenic space or epiploic foramen. There are fewer indications for laparoscopy in acute colic, though in some cases the technique can be useful for diagnosis, after which the procedure is converted to a hand-assisted laparoscopy. However, manipulation of the intestine is limited compared with an open laparotomy.

Gastrointestinal biopsy in the horse: overview of collection, interpretation, and applications

Evaluation of gastrointestinal (GI) biopsies is a multistep process that includes reviewing an appropriate history, determining sample quality, and evaluating histologic sections. Selected diagnostic parameters that, in combination with intestinal histopathology, can be useful to localize disease to the intestinal tract in the horse include hypoproteinemia and hypoalbuminemia, ultrasound evidence of increased thickness of the small intestinal wall, and alterations in glucose or D-xylose absorption tests. Biopsies may be acquired either endoscopically, or via laparoscopy or standing flank incisional approaches. GI sections should be evaluated using a systematic approach that includes both architectural changes and inflammatory cell infiltrates. Although strategies have been developed for assessment of GI biopsies from the dog and cat, a standardized approach to interpretation of the equine GI biopsy has yet to be developed. GI biopsies pose several challenges to the pathologist, especially for endoscopic biopsies in which the quality of the specimen and its orientation may vary greatly. Architectural changes are arguably the most critical changes to evaluate. In a horse with chronic GI inflammation, such as occurs in idiopathic inflammatory bowel disease (IBD), the cell types encountered frequently are macrophages, eosinophils, lymphocytes, and plasma cells. Increased numbers of these cell types are categorized loosely as mild, moderate, and severe. Specific forms of idiopathic IBD have been further classified by this infiltrate as granulomatous enteritis, eosinophilic enteritis, and lymphoplasmacytic enteritis; there is limited information on microscopic changes with each. Unfortunately, microscopic GI lesions are usually nonspecific, and determination of etiology requires further investigation.

Equine grass sickness in italy: a case series study

BACKGROUND

Equine grass sickness (EGS) has been reported in several European and extra-European countries. Despite this, no scientific paper about clinical cases of EGS in Italy has been published. EGS is a disease affecting almost exclusively horses kept on pasture, characterized by clinical signs related to lesions in autonomic nervous system (ANS), particularly in the enteric nervous system (ENS). According to clinical presentation, acute, subacute and chornic syndromes can be observed, with various sympthoms including dullness, anorexia, dysphagia, drooling of saliva, tachycardia, ptosis, patchy sweating and muscle fasciculations. In horses affected by acute forms, mild to moderate abdominal pain and large volumes of nasogastric reflux can be observed. The etiology is still speculative and many hypothesis have been proposed to explain the pathogenesis.

CASE PRESENTATION

The present study describes four cases of EGS (one subacute and three chronic forms) occurred in Central Italy during early spring. In all the cases included in the study, the prognosis was poor and the horses were euthanized. The diagnosis was confirmed by histological examination of ANS or ENS. In two cases, in vivo diagnosis was obtained by histological examination of enteric bioptic samples collected during laparoscopy.

CONCLUSIONS

EGS in Italy could be underdiagnosed and incidence understimated. Greater awareness should be applied in Italy for the inclusion of EGS in differential diagnosis for horses presenting clinical signs of abdominal pain associated or not with gastric reflux and muscular fasciculation. All the cases in this study concerned horses kept in the same pasture, confirming a possible premise-linked and management-linked factors on the ethiopathogenesis of EGS. The age of horses ranged from 2 to 6 years, that is consistent with the risk factor age for EGS (from 2 to 7 years of age). Previous suspected EGS diagnosis in the same livestock and recent cool dry weather were considered additional potential risk factors.

Laparoscopic evaluation of the small intestine in the standing horse: Technique and effects

OBJECTIVE

To evaluate the feasibility and clinical outcomes after laparoscopic evaluation of the small intestines via laparoscopy.

STUDY DESIGN

Prospective pilot study.

ANIMALS

Healthy adult horses (n = 5).

METHODS

Horses were restrained in standing stocks and received an infusion of detomidine. One port was placed in the left last intercostal space and 3 ports were placed in the right paralumbar fossa. The small intestine was run with atraumatic laparoscopic grasping forceps, from the duodenocolic plica to the ileocecal plica. Postoperative pain was scored every 4 hours for the first 48 hours. Horses were monitored via physical examinations for 2 weeks. Second look laparoscopy was repeated at 2 weeks, to run the small intestine and assess iatrogenic changes. An exploratory celiotomy was performed in 2 horses, 2 months later and long-term follow-up was recorded in 3 horses.

RESULTS

Laparoscopic evaluation of the entire small intestine was successfully completed twice in every horse. This evaluation lasted 39 ± 21.2 minutes (mean ± SD), while total surgery time was 73 ± 34.1 minutes. Postoperative physical examinations remained normal in all horses, and pain scores were scored as mild. The only abnormalities at second look laparoscopy consisted of multifocal petechiae and ecchymoses in all horses, resolved by 2 months in the 2 horses explored via celiotomy. Three horses with long-term follow-up were healthy 8 months after the study.

CONCLUSION

Running the small intestine laparoscopically is a feasible procedure in standing normal horses, and does not cause significant discomfort nor complications.

Standing diagnostic and therapeutic equine abdominal surgery

The widespread use of laparoscopy in equine surgery has increased interest in the standing approach to a wide range of procedures typically regarded as feasible only through a ventral midline incision. Although a commonly cited benefit of standing surgery relates to avoiding costs of general anesthesia and risks associated with it, some procedures and horses are not suitable candidates for standing abdominal procedures. Some procedures, such as nephrectomy, colostomy, and closure of the nephrosplenic space, are not only suitable for standing surgery but are performed more easily and more safely through this approach than with general anesthesia.

A review of equine laparoscopy

Minimally invasive surgery in the human was first identified in mid 900's. The procedure as is more commonly practiced now was first reported in 1912. There have been many advances and new techniques developed in the past 100 years. Equine laparoscopy, was first reported in the 1970's, and similarly has undergone much transformation in the last 40 years. It is now considered the standard of care in many surgical techniques such as cryptorchidectomy, ovariectomy, nephrosplenic space ablation, standing abdominal exploratory, and many other reproductive surgeries. This manuscript describes the history of minimally invasive surgery, and highlights many of the techniques that are currently performed in equine surgery. Special attention is given to instrumentation, ligating techniques, and the surgical principles of equine minimally invasive surgery.

Evaluation of a laparoscopic technique for collection of serial full-thickness small intestinal biopsy specimens in standing sedated horses

OBJECTIVE

To assess a technique for laparoscopic collection of serial full-thickness small intestinal biopsy specimens in horses.

ANIMALS

13 healthy adult horses.

PROCEDURES

In the ex vivo portion of the study, sections of duodenum and jejunum obtained from 6 horses immediately after euthanasia were divided into 3 segments. Each segment was randomly assigned to the control group, the double-layer hand-sewn closure group, or the endoscopic linear stapler (ELS) group. Bursting strength and bursting wall tension were measured and compared among groups; luminal diameter reduction at the biopsy site was compared between the biopsy groups. In the in vivo portion of the study, serial full-thickness small intestinal biopsy specimens were laparoscopically collected with an ELS from the descending duodenum and distal portion of the jejunum at monthly intervals in 7 sedated, standing horses. Biopsy specimens were evaluated for suitability for histologic examination.

RESULTS

Mean bursting strength and bursting wall tension were significantly lower in the ELS group than in the hand-sewn and control groups in both the duodenal and jejunal segments. Use of the hand-sewn closure technique at the biopsy site reduced luminal diameter significantly more than use of the stapling technique. In the in vivo part of the study, all 52 biopsy specimens collected during 26 laparoscopic procedures were suitable for histologic examination and no clinically important perioperative complications developed.

CONCLUSIONS AND CLINICAL RELEVANCE

Laparoscopic collection of serial full-thickness small intestinal biopsy specimens with a 45-mm ELS may be an effective and safe technique for use in healthy adult experimental horses.