Anastomotic techniques for small intestinal obstruction in horses. A scoping review.

BACKGROUND: Small bowel obstruction (SBO) is a significant cause of surgery in adult horses presenting with colic pain. SBOs often require resection and anastomosis. While various techniques for intestinal anastomoses have been developed, it remains uncertain if any fully meet our clinical needs. OBJECTIVE: To conduct a scoping review of publications on anastomosis techniques and outcomes for the treatment of SBO. STUDY DESIGN: Scoping review. METHODS: A literature review was conducted using the CAB, Web of Science, Scopus, and PubMed databases. Peer-reviewed scientific articles in English, published between 1992 and 2023, were included. A quality assessment was performed for potentially eligible articles. Experimental studies, case reports, and case series with less than five cases were excluded and relevant data on study methods and sample size were extracted and charted from remaining articles. Anastomosis type and outcome were reported for articles considered potentially eligible for meta-analysis. Articles in which only overall outcome was reported or details on type of anastomosis were not reported were excluded for the final charting. RESULTS: Of 3024 articles, 210 underwent a quality assessment. The most common study designs were case reports and case series (64.3%), followed by experimental studies (17.1%). After further exclusions, 104 articles met the inclusion criteria. In only 42 articles detailed data on type of anastomosis and relative outcome were reported. A total of 23 anastomosis types were reported for the treatment of SBO, with 6 different outcomes evaluated. Both short- and long-term survival rates consistently exceed 70% for all types of anastomosis (jejuno-jejunal, jejuno-ileal, and jejunocaecal). MAIN LIMITATION: Non-English language studies and conference proceedings were excluded. CONCLUSION: The body of literature focused on surgical treatment for SBO exhibits low-quality evidence. Several techniques of anastomosis were described for different pathologies. However, there is a lack of homogeneity in reporting outcome for each surgical technique. Furthermore, outcomes considered varied significantly among studies and were sometimes poorly reported, although success rates are generally high. Overall, there is a need for better-structured studies on existing and commonly used techniques before comparing techniques and exploring other innovative approaches.

Small Colon Faecalith with Large Colon Displacement in Ten Cases (2015-2023): A Detailed Case Description and Literature Review.

Small colon impaction can result in accumulation of ingesta, gas, and fluid orally to the impaction site in horses. Large colon tympany, which is caused by ingesta fermentation, can be a predisposing factor for intestinal displacement. The aim of this study is to report the history, clinical, and surgical findings of horses and ponies referred for abdominal pain not responsive to drugs where a right dorsal displacement (RDD) or large colon volvulus (LCV), together with a small colon faecalith (SCF), were diagnosed during surgery. This study included a total of five horses and five ponies. Based on clinical features, ultrasonographic examination, and rectal palpation, an initial suspected diagnosis of RDD, LCV or severe large colon and caecum distension was made in all clinical cases. Due to the lack of response to medical treatment or worsening of colic symptoms, surgery was performed in all horses: diagnosis of RDD or LCV was made and a SCF was incidentally detected in all cases. While exploratory laparotomy was carried out in all the patients for the presence of a large colon issue, it was probably subsequent to an obstruction of the small colon caused by the presence of an SCF, which is generally difficult to diagnose. This study reported the presence of SCF as a possible cause of secondary RDD or LCV in horses and ponies that, to the authors' knowledge, has never been reported.

The Effects of Pectin-Honey Hydrogel in a Contaminated Chronic Hernia Model in Rats.

Incisional hernia is a frequent complication after abdominal surgery. A previous study on rats evaluated the use of a Pectin-Honey Hydrogel (PHH)-coated polypropylene (PP) mesh for the healing of acute hernias. However, there are no studies investigating the use of PHH in association with PP mesh in chronic contaminated hernia. The aims of this study are to assess the effectiveness of PHH in promoting abdominal hernia repaired with PP mesh and in counteracting infection. Twenty Sprague Dawley male rats were enrolled and a full thickness defect was made in the abdominal wall. The defect was repaired after 28 days using a PP mesh, and a culture medium (Tryptone Soy Broth, Oxoid) was spread onto the mesh to contaminate wounds in both groups. The rats were randomly assigned to a treated or untreated group. In the treated group, a PHH was applied on the mesh before skin closure. At euthanasia-14 days after surgery-macroscopical, microbiological and histopathological evaluations were performed, with a score attributed for signs of inflammation. An immunohistochemical investigation against COX-2 was also performed. Adhesions were more severe (p = 0.0014) and extended (p = 0.0021) in the untreated group. Bacteriological results were not significantly different between groups. Both groups showed moderate to severe values (score > 2) in terms of reparative and inflammatory reactions at histopathological levels. The use of PHH in association with PP mesh could reduce adhesion formation, extension and severity compared to PP mesh alone. No differences in terms of wound healing, contamination and grade of inflammation were reported between groups.

Short-Term Survival and Postoperative Complications Rates in Horses Undergoing Colic Surgery: A Multicentre Study.

The occurrence of colic could be influenced by the characteristics of a population, geographical area, and feeding management. The aim of this study was to report the short-term postoperative complications and survival rates and to identify factors that might affect the outcome of horses that underwent colic surgery in three Italian surgical referral centres. Data of horses subjected to colic surgery in three referral centres (2018-2021) were analysed. Comparisons of the outcomes were performed using a Mann-Whitney or a Chi square test. Areas under the receiver operating characteristic (ROC) curve and multivariable logistic regression analysis were used for parameters that were significant in the previous univariate analysis. The goodness-of-fit of the model was assessed using the Akike information criterion (AIC). Significance was defined as p < 0.05, and odds ratios and 95% confidence intervals were calculated as percentages. A total of 451 horses were included. The survival rate was 68.5% of all of the horses that underwent colic surgery and 80% of the horses surviving anaesthesia. Age, BCS, PCV and TPP before and after surgery, amount of reflux, type of disease, type of lesion, duration of surgery, surgeon's experience, and amount of intra- and postoperative fluids administered influenced the probability of short-term survival. The multivariate analysis revealed that PCV at arrival, TPP after surgery, and BCS had the highest predictive power. This is the first multicentre study in Italy. The results of this study may help surgeons to inform owners regarding the prognosis of colic surgery.

Ex vivo evaluation of a technique for equine jejunocecal anastomosis using radiofrequency thermofusion and a Cushing oversew.

OBJECTIVE: To describe a technique for a side-to-side jejunocecal anastomosis in horses using radiofrequency thermofusion (TF) of the intestines supported by a Cushing oversew and to compare this anastomosis to handsewn and stapled techniques. STUDY DESIGN: Ex vivo study. SAMPLE POPULATION: Intestinal tracts from 24 slaughtered horses. METHODS: A radiofrequency device was used to perform a jejunocecal anastomosis (Group RFA). The construction time and bursting pressure of this construct were compared with those of a hand-sewn double layer (Group HS) and stapled anastomoses (Group ST) without oversew of the staple line. Histology was also performed for the TF anastomoses to evaluate the extent of the thermal damage. RESULTS: The median (range) construction time (min) for the TF (15.8 [14.4-16.8]) was not significantly different from that for the HS (25.5 [24.2-26.3]) and ST (10.8 [9.7-12.5]) groups (p = .07). The construction time for ST was shorter than that for HS group (p < .001). The average (standard deviation) bursting pressure (mmHg) for HS (153.1 +/- 17.5) was higher than that for RFA (76 +/- 15) and ST groups (48 +/- 13; p < .001). The bursting pressure of the RFA was higher than that of the ST anastomoses (p = .001). The thermal damage caused by the device was within the suture oversew in the deeper layers, whereas it extended a few mm beyond the suture line in the serosa. CONCLUSION: Radiofrequency assisted anastomoses provide similar construction times to current techniques and have a higher bursting pressure than ST anastomoses. CLINICAL SIGNIFICANCE: Radiofrequency-assisted anastomoses with a suture oversew demonstrated comparable bursting pressures to ST anastomoses. The use of the radiofrequency device on the intestine is extra label and causes serosal tissue damage, which may increase the risk of adhesions.

Development of a classification system for equine postoperative complications and its application in a cohort of 190 horses undergoing emergency laparotomy.

BACKGROUND: Accurate reporting of postoperative complications is paramount to understanding procedural outcomes, comparing procedures and assuring quality improvement. Standardising definitions of complications in equine surgeries will improve the evidence of their outcomes. To this end, we proposed a classification for postoperative complications and applied it to a cohort of 190 horses undergoing emergency laparotomy. METHODS: A classification system for postoperative complications in equine surgery was developed. Medical records of horses that underwent equine emergency laparotomy and recovered from anaesthesia were analysed. Reported complications pre-discharge were classified as per the new classification system, and the cost and days of hospitalisation were correlated with the equine postoperative complication score (EPOCS). RESULTS: Of the 190 horses that underwent emergency laparotomy, 14 (7.4%) did not survive to discharge (class 6 complications), and 47 (24.7%) did not develop complications. The remaining horses were classified as follows: 43 (22.6%) had class 1 complications, 30 (15.8%) had class 2, 42 (22%) had class 3, 11 (5.8%) had class 4; and three (1.5%) had class 5. The proposed classification system and EPOCS correlated with the cost and length of hospitalisation. LIMITATIONS: This was a single-centre study and the definition of scores was arbitrary. CONCLUSIONS: Reporting and grading all complications will help surgeons better understand the patients' postoperative course, thereby reducing subjective interpretation.

Use of a new device for inversion of the necrotic ileal stump in the caecum in four horses.

BACKGROUND: In jejunocaecal anastomosis leaving a necrotic ileal stump has been implicated in complications and poor outcomes. Elective inversion of the necrotic stump using a nasogastric tube has been previously described, although this procedure can be cumbersome and can cause caecocolic orifice occlusion. OBJECTIVE: To describe the use of a new device for elective inversion of necrotic ileal stumps. STUDY DESIGN: Case report. METHODS: Details of the four horses that underwent intestinal resection and anastomosis with elective inversion of the ileal stump were retrieved from their medical records. For each case, a device was constructed by securing 0.7 m of hemp tape to a 0.5 m long electrical cable puller. The device was inserted into the ileum and passed through the caecum. The ileal lumen was closed using sutures or staples, and the tape was simultaneously secured to the intestine. The ileum was then resected. A small typhlotomy was performed at the proposed site for jejunocaecal anastomosis. The device was retrieved, the hemp tape was cut, and jejunocaecal anastomosis was completed. RESULTS: The device was easily secured to the intestines. Small enterotomies were sufficient for device insertion and removal. In four clinical cases the procedure was effective in inverting the stump, and three out of the four horses recovered uneventfully and were discharged from the hospital. One horse was euthanised due to colic 27 months following discharge. MAIN LIMITATIONS: Small number of cases admitted to single tertiary hospital. CONCLUSIONS: The device was effective in inverting the ileal stump in the included clinical cases. By leaving a short, inverted stump, this method may help improve the prognosis for jejunocaecal anastomosis, possibly avoiding certain undesired effects of the procedure. Further studies with large numbers of cases are required.

Scoping review: Occurrence and definitions of postoperative complications in equine colic surgery.

BACKGROUND: Postoperative complications frequently occur following equine colic surgery but there is a lack of consistency in their definitions and reporting. OBJECTIVES: To perform a scoping review to identify current evidence on the definitions and classifications of postoperative complications in equine colic surgery. STUDY DESIGN: Evidence review. METHODS: A scoping review was conducted in CAB, Web of Science, Scopus and PubMed databases using a PCC (Population-equids, Concept-complications, adverse events, sequelae, failure to cure, technical failure, disease progression and Context-postoperative period after colic surgery) search strategy. Peer-reviewed scientific articles in the English language on equine colic surgery in live client-owned equids between 1992 and 2022 were included. The resulting references were independently and blindly screened by two investigators. Relevant data on the study method, sample size, intestinal tract involvement and postoperative complications were extracted and charted. RESULTS: Among 5850 articles potentially eligible, 272 met the final inclusion criteria. The most frequent types of study design were retrospective cohort studies (121/272) and retrospective case series (82/272). Median sample size was 53 animals, range 3-896. Seventy-nine of 272 (29%) studies reported diseases of the small intestine, 65 of 272 (24%) of the large intestine and 128 of 272 (47%) reported both. Seventy-two studies (26.4%) focused on single complications. No study explicitly defined the term complication or cited a classification of complications. One study reported the definitions of 'sequela', 'progression' or 'recurrence' of lesions. Eighty-one postoperative complications were reported in two-time frames defined as short- and long-term. The definitions of most complications and long-term follow-ups were highly variable. MAIN LIMITATION: Non-English language studies or conference proceedings were excluded. CONCLUSION: There was a substantial lack of classifications of postoperative complications. The definitions of complications were highly variable, making it difficult to compare studies. Adopting classification systems and definitions may help surgeons to obtain a complete picture of the efficacy of a procedure or treatment and allow comparisons between studies, centres or time periods.

Changes in Perioperative Antimicrobial and Anti-Inflammatory Drugs Regimens for Colic Surgery in Horses: A Single Center Report.

Reducing postoperative incisional infection is the main reason to administer postoperative antimicrobials (AMD) after emergency laparotomy in horses, while reducing inflammation and providing analgesia are the reasons to administer anti-inflammatory drugs (AID). The basis for postoperative AMD and AID administration is empirical and only recently has been questioned. Empirical approaches can be changed, and these changes, along with the description of their outcomes, can help produce appropriate stewardship. The aim of this study is to report the changes in AMD and AID regimens in horses undergoing emergency laparotomy at a referral teaching hospital between 2017 and 2021. Signalment, pathology, surgery, prophylactic AMD and AID administration were obtained from the medical records. Difference in AMD and AID regimens throughout the study period were also reported. In 234 postoperative records considered, ninety-two horses received prophylactic AMD, while 142 received pre-operative antimicrobials only. There was a progressive change in regimens throughout the years, increasing the number of AID molecules used. AMD and AID administration in horses has changed in our practice over the years to modulate therapies according to the postoperative complications that eventually arise. In this study, horses not receiving postoperative routine AMD treatment did not show an increased incidence of complications.

Occurrence and Definitions of Intra and Postoperative Complications Related to Laparoscopy in Equids: A Scoping Review.

Laparoscopy is a common approach in equine surgery and has the advantage of improved visibility and diagnostic accuracy, decreased morbidity and hospitalization time. However, despite the numerous benefits, there can be intraoperative and postoperative complications which could have important welfare and economic consequences. The aim of this study was to perform a scoping review to identify current evidence on the occurrence, definition and classification of intra and postoperative complications in equine laparoscopy. A scoping review was conducted in scientific databases. Peer-reviewed scientific articles in the English language on laparoscopy in equids between 1992 and 2022 were included. Data on the study method, sample size, surgical procedure, intra and postoperative complications were extracted and charted. One hundred sixty-four articles met the final inclusion criteria. A definition of "intraoperative complication" was given in one study. Difference between "minor" or "major" intraoperative complications were reported in 12 articles and between "minor" or "major" postoperative complications in 22 articles. A total of 22 intraoperative and 34 postoperative complications were described. The most reported intraoperative complication was hemorrhage from ovary or mesovary (12.7%), while the most reported postoperative complications were incisional complications (64.2%) and postoperative pain (32.7%). There is a need for implementation of criteria for defining complications. The adoption of classification systems and standard definitions would help surgeons to make decisions about the most appropriate treatment, and it is also essential to allow comparisons between research results.

Transillumination Techniques for Vessel Identification During Small Colon Resection in Six Horses.

BACKGROUND: Transillumination has been described in human surgery to improve vessel visualization but has not been described in horses. Since the equine mesocolon contains a great amount of fat which restricts visualization of the vessels, this technique could be useful during small colon resection. OBJECTIVES: To describe transillumination of the mesocolon to provide an improved vessel identification during resection and anastomosis of the small colon in horses. METHODS: Data of horses that underwent resection and anastomosis of small colon were recorded. Two transillumination techniques were used during resection and anastomosis of small colon. In a first technique, used on three horses, the operating lamp was used. It was lowered and tilted so that the assistant surgeon could lift the small colon so that the mesentery was between the lamp and the first surgeon eyes. In a second technique, used on further three horses, a smartphone with a rear LED flashlight turned on was placed into a sterile rectal sleeve. The device was placed on the surgical field and the portion of small colon to be resected was then laid over the smartphone, to backlight the vessels. The vessels were then identified and ligated. RESULTS: Six horses referred for acute colic that underwent resection and anastomosis of the small colon were included in the study. Using both transillumination technique the mesocolon was backlit and the vessels were clearly and easily identified, dissected, ligated, and transacted without complications. The smartphone technique subjectively ensured a better operating position for the surgeon and less fatigue for the assistant. CONCLUSIONS: Transillumination techniques are useful to avoid damage when ligating vessels and using the flashlight of a smartphone is easier and provide safer and more accurate transection of them during small colon resection and anastomosis.

Combination of end-to-end jejuno-ileal anastomosis and side-to-side incomplete ileocecal bypass (hybrid jejuno-ileo-cecal anastomosis) following subtotal ileal resection in seven horses.

CASE DESCRIPTION: 7 horses (3 geldings, 2 mares, and 2 stallions) were examined because of acute colic caused by small intestinal obstruction involving the aborad portion of the jejunum and orad portion of the ileum. CLINICAL FINDINGS: All horses underwent a routine colic examination on arrival and had a diagnosis of strangulating obstruction of the small intestine. TREATMENT AND OUTCOME: All horses underwent emergency exploratory laparotomy, in which the affected aborad portion of the jejunum and orad portion of the ileum were resected; in 5 horses, a hand-sewn end-to-end jejuno-ileal anastomosis was combined with a hand-sewn incomplete ileocecal bypass to produce a hybrid jejuno-ileo-cecal anastomosis. In 2 horses, the hand-sewn end-to-end jejuno-ileal anastomosis was combined with a half-stapled, half-hand-sewn incomplete ileocecal bypass. The procedures restored continuity of the small intestine with partial bypass of the ileocecal valve. All horses survived to hospital discharge, and none developed colic or ileus during the postoperative period. Follow-up revealed that 6 horses were living and had no subsequent signs of colic (4 to 17 months after surgery), and 1 was euthanized because of colic 17 months after surgery. CLINICAL RELEVANCE: Results for these horses suggested the hybrid jejuno-ileo-cecal anastomosis could be considered as an option for the resolution of small intestinal strangulating lesions involving the orad portion of the ileum. Studies are needed to assess short-term and long-term effects of the procedure in horses.

Comparison of liberal and goal-directed fluid therapy after small intestinal surgery for strangulating lesions in horses.

BACKGROUND: There are few guidelines for the appropriate mode of fluid administration during and after colic surgery, and is challenging to reach the right balance while avoiding overhydration. This study aimed to compare goal-directed fluid therapy (GDFT) and 'liberal' fluid regimens (LFRs) in horses undergoing small intestinal surgery. METHODS: Eighteen horses subjected to small intestinal surgery were matched according to the surgical lesion, type of anastomosis, length of resection, and duration of clinical signs. Horses in the LFR group were administered intravenous (IV) fluids for at least 24 h. In the GDFT group, IV fluids were administered only when considered necessary based on clinical parameters. Postoperative reflux (POR), packed cell volume, total protein, heart rate, venous lactate level, complications, and long-term survival rates were compared. RESULTS: Three horses in the LFR and one in the GDFT group developed POR. Horses in the GDFT group had a shorter time interval to first oral water intake and shorter hospitalisation time. Postoperative complication rates and survival were not different between groups. CONCLUSION: Further studies are necessary to set guidelines for the evaluation of hydration status and to plan postoperative fluid administration; however, GDFT may be a valid alternative to liberal fluid therapy after colic surgery.

In Vivo Evaluation of a Pectin-Honey Hydrogel Coating on Polypropylene Mesh in a Rat Model of Acute Hernia.

Investigations about ventral hernia repair are focused on improving the quality, resistance, and biocompatibility of mesh. This study compared plain polypropylene mesh with a pectin-honey hydrogel-coated polypropylene mesh in an acute hernia model in rats. Forty Wistar rats, randomly assigned to two groups, were submitted to laparotomy, and a 1 cm × 2 cm fascial defect was created, centered on the midline. Uncoated (group C) or coated mesh (group T) was inserted in an inlay fashion to repair the defect. After 30 days, the rats were euthanized, and the presence of adhesions to the mesh was macroscopically evaluated. Histology and measurement of COX-2 as tissue inflammation markers were used to assess fascia tissue healing. Grades of adhesion were not different between groups. Histological score and COX-2 expression were not significantly different between groups, except for the higher inflammatory response demonstrated in group T. The pectin-hydrogel coated mesh could not reduce adhesion formation compared to uncoated polypropylene mesh but improved peritoneal regeneration and tissue healing.

Effect of sugar metabolite methylglyoxal on equine lamellar explants: An ex vivo model of laminitis.

Laminitis is one of the most devastating diseases in equine medicine, and although several etiopathogenetic mechanisms have been proposed, few clear answers have been identified to date. Several lines of evidence point towards its underlying pathology as being metabolism-related. In the carbonyl stress pathway, sugars are converted to methylglyoxal (MG)-a highly reactive α-oxoaldehyde, mainly derived during glycolysis in eukaryotic cells from the triose phosphates: D-glyceraldehyde-3-phosphate and dihydroxyacetone phosphate. One common hypothesis is that MG could be synthesized during the digestive process in horses, and excessive levels absorbed into peripheral blood could be delivered to the foot and lead to alterations in the hoof lamellar structure. In the present study, employing an ex vivo experimental design, different concentrations of MG were applied to hoof explants (HE), which were then incubated and maintained in a specific medium for 24 and 48 h. Macroscopic and histological analyses and a separation force test were performed at 24 and 48 h post-MG application. Gene expression levels of matrix metalloproteinase (MMP)-2 and -14 and tissue inhibitor of metalloproteinase (TIMP)-2 were also measured at each time point for all experimental conditions. High concentrations of MG induced macroscopic and histological changes mimicking laminitis. The separation force test revealed that hoof tissue samples incubated for 24 h in a high concentration of MG, or with lower doses but for a longer period (48 h), demonstrated significant weaknesses, and samples were easily separated. All results support that high levels of MG could induce irreversible damage in HEs, mimicking laminitis in an ex vivo model.

Gastric and Large Colon Impactions Combined With Aggressive Enteral Fluid Therapy May Predispose to Large Colon Volvulus: 4 Cases.

To resolve large colon impactions, frequent enteral administration of large volumes of water (8-10 liters in a 500 kg horse) has been suggested. Furthermore, in large colon volvulus, the simultaneous presence of gastric impaction has been described as a possible predisposing factor. To describe the clinical and surgical features of horses with large colon volvulus associated with aggressive enteral fluid therapy performed to resolve an initial large colon impaction. Records of horses that underwent exploratory laparotomy at the Veterinary Teaching Hospital of Turin between 2012-2019 were reviewed. Clinical and surgical features of cases initially diagnosed with large colon impaction that developed a large colon volvulus after enteral administration of large volumes of fluids were retrieved. Four horses met the criteria. In all horses an initial diagnosis of large colon impaction was made by the referring veterinarian. In all cases a sudden increase in pain was noticed shortly after enteral administration of large volumes (8-10 liters) of water. Administration of analgesic didn't resolve the pain in any of the horses that were then referred. A large colon volvulus was found during exploratory laparotomy in all cases. A moderate gastric impaction was also found intraoperatively, which was confirmed by gastroscopy postoperatively. Nasogastric administration of large quantity of fluids with a pre-existing gastric and colon impaction, may reduce the available space in the abdominal cavity and potentially predispose the colon volvulus. More frequent enteral administration of smaller volumes of fluids might be preferred when treating large colon impactions.

Comparison of Mesh and Barbed Suture for Laparoscopic Nephrosplenic Space Ablation in Horses.

Nephrosplenic space (NSS) ablation has been demonstrated to be an effective technique for prevention of left dorsal displacement of the large colon and multiple laparoscopic techniques, among which ablation with mesh or with a barbed suture, have been proposed. Our objective was to compare two laparoscopic techniques for closure of the NSS in twenty-eight horses diagnosed with nephrosplenic entrapment. Medical records of horses that had laparoscopic NSS ablation in two referral centers between 2017-2019 were retrieved. Duration of surgery, complications, and short- and long-term follow-up information were collected and compared. Costs were also calculated and compared. All horses met the inclusion criteria: 9 had NSS ablation with a mesh implant (group M), 19 with barbed suture material (group B). One horse in group B had recurrent colic after discharge. At control laparoscopy after 5 months, the NSS resulted in still not being ablated because of a failure of the suture. In group M, three horses had recurrent colic. One was successfully treated medically, one died of unknown causes and the third required a second laparoscopic suturing at 3-6 months because of failure of the mesh implant. The mean time of surgery and costs were lower in group B compared to group M. The barbed suture technique was faster, more cost-effective and had a lower complication rate than the mesh implant.

Incomplete Ileocecal Bypass for Ileal Pathology in Horses: 21 Cases (2012-2019).

BACKGROUND: Incomplete ileocecal bypass can be performed in cases in which an ileal disfunction is suspected but resection of the diseased ileum is not necessary. OBJECTIVES: To describe the clinical findings, the surgical technique, and the outcome of 21 cases of colic with ileal pathologies that underwent an incomplete ileocecal bypass. METHODS: Historical, clinical, and surgical features of cases diagnosed with pathologies involving the ileum or the ileocecal valve that underwent ileocecal anastomosis without ileal resection were retrieved. Clinical (heart rate, duration of symptoms, presence of reflux, age, weight at arrival) and surgical (surgical pathology, duration of surgery, type of anastomosis) data were retrieved and analysed. Data on short term survival and postoperative complications (colic, post-operative reflux, incisional infection, fever), length of hospital stay, and long term follow up were also obtained. RESULTS: A total of 21 horses met the criteria; 13 horses had ileal impaction (one with muscular hypertrophy), 5 horses had epiploic foramen entrapment, and 3 horses had a pedunculated lipoma. An incomplete ileocecal bypass was performed with a two-layer hand-sewn side-to-side technique in 19 cases and with a stapled side-to-side technique in 2 cases. Short term survival was 95.2%. At 12-months follow up, all horses but two were alive, and 13 of the 14 sport horses returned to their previous level of activity. Long term survival was 90.47%. Conclusions Incomplete ileocecal bypass may represent a valid surgical technique in case of ileocecal valve disfunction when ileum resection is not necessary; this technique may represent an alternative to extensive manipulation without subsequent recurrence of ileal impaction.

Ex vivo comparison of sliding knot ligatures vs. haemostatic clips for equine small intestinal mesenteric vessel occlusion.

BACKGROUND: In equine abdominal surgery, resection and anastomosis of strangulated intestine is a commonly performed procedure. To date, ligatures, vessel sealing devices and the ligate-divide stapler have been described for this use in horses. The objective of this study was to compare the application of haemostatic clips and ligatures to occlude equine mesenteric vessels. Portions of jejunum with ten associated mesenteric vessels were collected from 12 horses at a local abattoir and divided into two groups. Portions of intestine were divided into two sections comprising five vessels each and assigned to Group A or Group B. Each vessel was occluded with a triple ligature. In Group A, vessels were ligated with three circumferential ligatures tied with a sliding knot with two overthrows. In Group B, vessels were occluded with application of three haemoclips. The procedures were performed by the same experienced surgeon. Intestinal length, construction time and vessel leaking pressure were measured and compared between groups. RESULTS: The intestinal length (mean ± SD) was 3.78 ± 0.43 m in Group A and 3.04 ± 0.83 m in Group B. The difference was not significant (p = 0.297). The construction time (mean ± SD) was 7.03 ± 0.34 min in Group A and 2.40 ± 0.43 min in Group B. The difference was significant (p < 0.0001). The leaking pressure was 1000 (750-1050) mmHg (median, IQ range) in Group A and 1050 (800-1050) mmHg (median, IQ range) in Group B. The difference was not significant (p = 0.225). CONCLUSIONS: Haemoclip application is comparable in terms of leaking pressure but quicker than sliding knots to apply.

Evaluation of three ligatures in simulated equine open castration.

OBJECTIVE: To compare three surgical knots for preventing leakage from the vascular bundle during ligation in simulated equine open castrations. STUDY DESIGN: Randomized, case-control, in vitro study. SAMPLE POPULATION: Testes (N = 60) collected from 30 horses. METHODS: Testes were collected from 30 horses and randomly assigned to one of three groups: group G (friction, giant knot), group T (modified transfixing knot), or group S (sliding, strangle knot; n = 20/group). The assigned knot was used to ligate the vascular bundle during open castration. The length of suture material used and the leak pressure of the testicular artery were measured and compared between groups. RESULTS: Strangle knots consistently leaked at higher pressures (median, 735.5 mm Hg; interquartile range [IQR], 735.5-735.5) compared with giant (median, 441.3 mm Hg; IQR, 367.8-643.6) and transfixing (median, 419.2 mm Hg; IQR, 323.6-643.6; P < .0001) knots. Both the strangle (median, 5 cm; IQR, 4.5-5.5) and giant (median, 6 cm; IQR, 5.35-6.075) knots required less suture material compared with the transfixing (median, 9.2 cm; IQR, 8.425-10.38; P < .0001) knot. CONCLUSION: The three surgical knots tested withstood pressure well above physiological levels in simulated open castrations. The strangle knot withstood higher pressure and required similar (giant) or less (transfixing) suture material than the other two knots. CLINICAL SIGNIFICANCE: This study provides evidence to support the use of a strangle knot to ligate the vascular bundle during simulated open castrations in horses.