In vitro evaluation of an inverted end-to-end equine jejunojejunal anastomosis using skin staples

OBJECTIVE: To compare functional indices of end-to-end (EEA) jejunojejunal anastomosis using skin staples in horses with a 2-layer inverting hand-sewn technique. STUDY DESIGN: Experimental study. SAMPLE POPULATION: Jejunal segments from 8 fresh equine cadavers. METHODS: For each bowel segment, 2 EEA anastomoses were created: one 2-layer hand-sewn and one 1-layer using skin staples. Time for anastomosis creation was recorded and compared. Lumen diameter of each anastomosis was measured on digital radiographs after intraluminal instillation of contrast medium and inflation of the jejunal segments to 14 mm Hg. Anastomotic indices (a compensated measure of stoma diameter) and bursting pressure were determined. RESULTS: EEA jejunal anastomosis using skin staples was significantly faster than use of a 2-layer hand-sewn technique. Anastomotic index, a measure of lumen size, was significantly larger with the skin-staple technique; however, the bursting pressure of stapled anastomoses was significantly less than for the hand-sewn technique, but the values were well above those reported for other anastomotic techniques. CONCLUSIONS: An anastomotic technique using skin staples was easy to learn and perform, effective and faster, and mechanically comparable with a hand-sewn 2-layer technique. CLINICAL RELEVANCE: The staple technique could be beneficial in equine gastrointestinal surgery by reducing anastomosis time, although further in vivo studies are needed to establish clinical safety.     

Comparison of staple and suture techniques for end-to-end anastomosis of the small colon in horses

Two techniques for end-to-end anastomosis of the small colon were evaluated in each of 6 horses. A simple interrupted suture pattern that excluded the mucosa and was oversewn with an inverting suture was compared with a triangulated double-row pattern of stainless steel staples. Anastomotic sites were evaluated at 2 weeks, 2 months, and 6 months for extent of abdominal adhesions, lumen diameter at anastomotic sites, bursting pressures, and healing response. Clinical postoperative complications were not associated with either technique. At postmortem examination, there was extensive adhesion formation from the mesocolon to the stapled anastomotic site. The suture technique resulted in greater luminal diameters (P less than or equal to 0.05), with good apposition of the tissue layers. Staples were missing as early as 2 weeks after surgery, and their loss was associated with separation of the muscularis at later evaluation periods. Regardless of technique, all but one anastomotic segment burst away from the anastomotic site along the mesenteric taenial band. For the 12 anastomoses performed in normal horses, the suturing technique was better than the stapling technique because of significantly larger lumen diameters, better anastomotic healing, and minimal intra-abdominal adhesion formation.     

In vitro evaluation of a closed-bowel technique for one-layer hand-sewn inverting end-to-end jejunojejunosotomy in the horse

OBJECTIVE: To report a technique for closed-bowel 1-layer inverting end-to-end jejunojejunal anastomosis in horses. STUDY DESIGN: Experimental study. SAMPLE POPULATION: Fresh cadaveric jejunal segments from 12 horses. METHODS: For each bowel segment a 1-layer closed and a 2-layer inverting end-to-end jejunojejunosotomy was created. Anastomosis construction time and anastomotic bursting pressure were measured and compared. RESULTS: Closed-bowel anastomosis was significantly faster to create than a 2-layer technique. Luminal narrowing (<30%) was similar with both techniques and comparable with other inverting techniques. Bursting pressure was significantly higher for the 2-layer technique, although all anastomoses resisted pressures higher than those reported for other jejunojejunal anastomosis techniques. CONCLUSIONS: A 1-layer hand-sewn, closed, inverting jejunojejunosotomy using a modified Doyen clamp was easy and faster to perform, and resulted in functional characteristics similar to, a 2-layer hand-sewn inverting technique. CLINICAL RELEVANCE: A closed, 1-layer inverting technique could be considered for equine jejunal anastomosis but requires in vivo evaluation before recommendation for clinical use.     

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.     

Effect of carboxymethylcellulose and hyaluronate solutions on jejunal healing in horses

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.     

A Comparison of Simple Continuous Versus Simple Interrupted Suture Patterns for Tracheal Anastomosis After Large-Segment Tracheal Resection in Dogs

Two suture techniques for tracheal anastomosis after large-segment tracheal resection were compared. Eight cartilages were resected from the trachea of each of 12 dogs; anastomoses with 4-0 polydioxanone suture were created using a simple continuous suture technique in six dogs and a simple interrupted suture technique in six dogs. Surgical time was shorter but apposition of tracheal segments at the time of surgery was less precise with the simple continuous suture technique. The dogs were evaluated for 150 days after surgery. Clinical abnormalities after tracheal resection and anastomosis were not observed. Percent dorsoventral luminal stenosis was calculated by measuring the tracheal lumen diameter on lateral cervical radiographs. Percent luminal stenosis was calculated planimetrically using a computerized digitizing tablet. Anastomotic stenosis was mild in all dogs; however, the mean percent luminal stenosis determined planimetrically was significantly greater for dogs that had the simple continuous suture technique. Planimetric measurements of cross-sectional area made before and after formalin fixation were not significantly different. Radiographic determination of percent dorsoventral luminal stenosis was a poor predictor of diminution of cross-sectional area determined planimetrically.     

Long-term prospective evaluation of intestinal anastomosis using stainless steel staples in 14 dogs

This prospective clinical study evaluated the use, complications, and clinical and ultrasonographic follow-ups of end-to-end intestinal anastomoses with skin staples in naturally occurring diseases in canine small and large intestines. Intestinal anastomoses were performed in 14 dogs and pre-, peri-, and postoperative data were recorded. Postoperative clinical and ultrasound evaluations were performed at regular intervals for 1 year. The mean time taken to construct the anastomosis was 5 min. There were no intraoperative complications. Hemorrhage and colonic stricture were the main postoperative complications. Staple loss occurred in 2 cases. Absence of wall layering and focal wall thickening were observed in all cases at each ultrasonographic follow-up. Hyperechoic fat was observed in all but 1 of the cases at month 1. Nine dogs were alive with normal digestive function at the end of the study. The skin stapler technique enabled rapid construction of consistent anastomoses with inexpensive stapling material.     

Comparison of one-layer (continuous Lembert) versus two-layer (simple continuous/Cushing) hand-sewn end-to-end anastomosis in equine jejunum

OBJECTIVE: To evaluate single and double layer end-to-end anastomosis in equine jejunum. STUDY DESIGN: Experimental in vitro study. ANIMALS: Mid-jejunal sections from 12 adult horses without gastrointestinal disease. METHODS: Jejunal end-to-end anastomoses were performed by a continuous Lembert pattern or a simple continuous pattern oversewn with a Cushing pattern. Jejunal segments were distended with fluid at 1 L/min, and intraluminal pressure at failure, and mode of failure were recorded. Bursting pressure and bursting wall tension were calculated. Anastomosis construction time and degree of luminal reduction were recorded. Results- Single layer anastomoses were constructed in less time than 2-layer anastomoses. Both anastomotic techniques resulted in luminal reduction compared with control tissue; however, the reduction was smaller with a 1-layer continuous Lembert anastomosis. No differences were noted in bursting pressure or bursting wall tension between groups. CONCLUSIONS: Anastomosis using a 1-layer continuous Lembert pattern resulted in a larger stoma, was faster to perform, and as strong as a 2-layer anastomosis. CLINICAL RELEVANCE: Use of a 1-layer continuous Lembert pattern for jejunojejunosotomy may be beneficial by decreasing anastomosis time and produce a larger stoma than a 2-layer anastomosis.     

A comparison of the mechanical strength of two stapled anastomosis techniques for equine small intestine

OBJECTIVE: To compare bursting strength, time of construction, and cost of a closed one-stage, stapled functional end-to-end jejunojejunostomy (FEE) with a stapled side-to-side jejunojejunostomy (STS). STUDY DESIGN: Experimental, randomized block design. ANIMALS: Seven adult horses without gastrointestinal disease. METHODS: The jejunum was isolated, and three FEE, three STS, and three control segments were created in each horse using a randomized block design. Anastomosis time was recorded. The intraluminal pressure at failure and mode of failure were recorded. Length at failure was measured on digitized images. Bursting pressure (BP), bursting wall tension (BWT), anastomosis time, and cost were compared. RESULTS: Control jejunal segments were stronger (P < or = .0001) in bursting strength and bursting wall tension (P < or = .0001) than either anastomosis type; no difference was found between anastomosis types for either variable. Functional end-to-end jejunojejunostomy was significantly quicker and less costly than STS (P < or = .0001). CONCLUSIONS: Mechanically there were no significant differences between the FEE and STS techniques. The FEE technique maintained the physiologic direction of peristalsis of the segments, required less tissue manipulation, and was faster and more economical to create. CLINICAL RELEVANCE: The FEE is a clinically viable technique.     

Comparison of single layer staple closure versus double layer hand-sewn closure for equine pelvic flexure enterotomy

Our objective was to compare thoracoabdominal (TA Premium™ 90) stapled enterotomy closure to traditional hand-sewn closure, using time to perform the technique, luminal diameter, and bursting pressure in ex-vivo specimens. The pelvic flexures of 13 client-owned horses were harvested. Each pelvic flexure had 1 enterotomy performed; 6 were closed via staples, 7 closures were hand-sewn. Luminal diameter at the enterotomy site was assessed via contrast radiography performed pre-and post-enterotomy. Bursting pressure of the closure was assessed by continuous manometry during rapid infusion. Time to perform stapled closure was significantly shorter than hand-sewn closure (P < 0.0001). Percent reduction of luminal diameters was significantly decreased in stapled specimens (P = 0.034). There was no significant difference in bursting strength between closure techniques (P = 0.196). In conclusion, stapled enterotomy closure offers statistically significant reduction in closure time and better maintains pre-enterotomy luminal diameter without reducing biomechanical strength, compared to a double layer hand-sewn closure.     

Clinical assessment and outcome of three techniques for jejunal resection and anastomosis in horses: 59 cases (1989-2000)

OBJECTIVE: To compare postoperative complications, short- and long-term survival, and surgical times for hand-sewn end-to-end (EE), stapled functional end-to-end (FEE), and stapled side-to-side (SS) anastomotic techniques for jejunal resection in horses. DESIGN: Retrospective study. ANIMALS: 59 horses. PROCEDURE: Medical records were reviewed to obtain signalment, diagnosis, treatment, and outcome for horses that underwent jejunojejunostomy in our hospital. Only horses that recovered from anesthesia were included in the study. RESULTS: Among the 59 horses, there were 33 EE, 15 FEE, and 11 SS anastomoses. No difference was found in duration of surgery among the 3 techniques. The most common postoperative complications were colic episodes (56%), ileus (53%), diarrhea (20%), and adhesions (15%). Horses with SS anastomosis had a significantly shorter duration of postoperative ileus than the EE group did. No significant difference in duration of postoperative ileus was found among the other groups. No difference was found among the 3 anastomotic techniques in regard to survival rate at the time of discharge, 6 months after surgery, or 1 year after surgery. Overall survival rates after jejunal anastomosis were 88% at the time of discharge, 65% at 6 months after surgery, and 57% at > or = 1 year after surgery. CONCLUSIONS AND CLINICAL RELEVANCE: The hand-sewn EE, stapled FEE, and stapled SS anastomotic techniques should be considered equivalent methods for small intestinal anastomosis in the horse. However, the stapled SS technique may be preferred because of possible decreased duration of postoperative ileus.     

Endoscopy and autopsy follow-up of biodegradable oesophageal anastomoses in dogs

The biofragmentable Anastomosis Ring (BAR) is a mechanical device composed of absorbable material and creates an inverting, atraumatic compressive anastomosis with no foreign material at the anastomotic site after healing. The aim of the present experimental study was to assess the safety of oesophagoscopy in early days after oesophageal anastomoses performed with the BAR and to follow-up the healing of BAR anastomoses by in vivo endoscopy and autopsy examination. Thirty mongrel dogs divided into subgroups according to the time-points of endoscopy and autopsy (4th, 7th, 14th, 28th day) were used. There was no significant difference in the healing of anastomoses performed under or above the tracheal bifurcation. Pleural adhesions helped to cover and seal small subclinical leaks. The mortality was 13.3% (4 dogs) and the overall leakage rate 14.3%. We looked for bleeding, haematoma, erosion, ulceration and granulation tissue in the anastomosis. Due to the high mechanical strength of these anastomoses, oesophagoscopy was a safe, easy and feasible method for follow-up BAR intrathoracic anastomoses, with no significant difference between the number of lesions found with endoscopy as compared to the autopsy data. The overall sensitivity of oesophagoscopy to discover mucosal lesions was 73.1%. Endoscopy had no complications, therefore it is a useful method of follow-up and may help predict the normal or compromised healing of oesophageal anastomoses.     

Open Intestinal Anastomosis with Surgical Stapling Equipment in 24 Dogs and Cats

Surgical stapling equipment was used to perform open antiperistaltic side-to-side ("functional end-to-end") entero-anastomoses in 20 dogs and 4 cats. Twenty-one anastomoses healed uneventfully. Seven animals with severe bacterial peritonitis required open peritoneal drainage and delayed abdominal closure. There was postoperative leakage at the anastomotic site in two dogs and a localized abscess at the staple line in one cat. No long-term complications occurred in follow-up periods of 3 to 29 months.     

Subtotal Colectomy With Surgical Stapling Instruments Via a Trans-cecal Approach for Treatment of Acquired Megacolon in Cats

Surgical stapling equipment was used to perform an end-to-end colonic anastomosis in 15 cats for the treatment of acquired megacolon. An end-to-end stapling device was passed to the anastomotic site by a trans-cecal approach. Subsequent closure of the cecal incision was accomplished with a thoracoabdominal stapling device. Two cats had hemorrhagic episodes immediately after surgery that required blood transfusions. All 15 cats have had good to excellent health after subtotal colectomy and colocolostomy performed using this stapling technique. Results of this study have demonstrated that "single surgical field" placement of the end-to-end stapling device has the primary advantage of simplicity and a lower chance of contamination compared with (dual field) rectal passage of similar devices. Closure of the cecal access incision is easily performed without reducing the diameter of the large intestinal lumen. The stapling technique provided an efficient and consistent method for anastomosis of the large bowel in cats.     

A Potential Technique Error in Stapled Side-to-Side Anastomosis of the Small Intestine of the Horse

Anastomotic leakage was noted to occur at the junction of the staple lines used to create the stoma during small intestine side-to-side anastomosis. The anastomosis was performed in a clinical equine patient by joining the lateral surfaces of the intestinal segments using a gastrointestinal anastomosis stapling instrument (GIA). The cause of this problem was investigated by performing six anastomoses in the jejunum of a single anesthetized adult horse using the GIA; three anastomoses were created by joining the antimesenteric edges of the bowel segments and three anastomoses were created by joining the lateral surfaces of the bowel segments. Bowel segments were then dissected to examine the stoma and the integrity of the staple lines. No defects were detected in anastomoses performed by joining the antimesenteric edges. Anastomoses performed by joining the lateral surfaces all had a defect at the junction of the double rows of staples used to create the stoma. Such defects would have allowed leakage of fluid and/or ingesta at the anastomotic site.     

Effect of carboxymethylcellulose and a hyaluronate-carboxymethylcellulose membrane on healing of intestinal anastomoses in horses

OBJECTIVE: To evaluate the effect of sodium carboxymethylcellulose (SCMC) or a hyaluronate-carboxymethylcellulose membrane (HA membrane) on healing of the small intestine in horses. ANIMALS: 18 healthy adult horses. PROCEDURE: Midline celiotomy and 2 jejunal resection-and-anastomosis surgeries were performed. In treated horses, SCMC (n = 6) or a HA membrane (6) was applied to the jejunum to cover the anastomosis. There were 6 untreated control horses. Horses were euthanatized 10 days after surgery. For each horse, 1 anastomosis was used for histologic examination, and the second was used to determine intestinal bursting strength. Intestinal bursting tension, serosal granulation tissue, serosal fibrin deposition, and width of the fibrous seal at the anastomosis were compared among groups. RESULTS: 3 control horses had adhesions associated with the anastomosis, but none of the treated horses had adhesions associated with the anastomosis. Mean thickness of fibrin deposited on the serosal surfaces for the SCMC and HA-membrane groups was significantly less than that for control horses. Mean thickness of serosal granulation tissue, width of fibrous seal between inverted musculature, inflammatory cell infiltrate scores, and bursting tension did not differ significantly among groups. CONCLUSIONS AND CLINICAL RELEVANCE: Use of SCMC or application of a HA membrane to small intestinal anastomoses in horses resulted in fewer adhesions and decreased fibrin deposition, and it did not adversely affect anastomotic healing. In horses at increased risk for intra-abdominal adhesions, SCMC or application of HA membranes may decrease the frequency of adhesions without adversely affecting healing of small intestinal anastomoses.     

Evaluation of a skin stapler for belt-loop gastropexy in dogs.

A new method for attachment of a belt-loop gastropexy using disposable, stainless steel skin staples was compared with a traditional hand-sewn belt-loop gastropexy technique in 24 fresh dog cadavers. Mean gastropexy times were 212 seconds for the stapled technique and 435 seconds for the hand-sewn technique. The stapled belt-loop gastropexy was significantly faster than the hand-sewn technique (P less than 0.001). There was no statistically significant difference in the mean maximum tensile strength between the two attachment methods. This study provides a basis for clinical evaluation of the stapled belt-loop gastropexy technique in dogs.     

Use of a linear stapling device to construct an inverted, triangulated, end-to-end anastomosis of the equine jejunum

An inverting, triangulated, stapled, end-to-end anastomosis technique was evaluated in the jejunum of four horses. None of the horses showed evidence of gastrointestinal disturbance after surgery; however, stricture and adhesion formation were pronounced in three animals examined 10 days, one month, and two months after surgery. The animal examined four months after surgery had no adhesions present at the anastomosis, and only mild narrowing of the intestinal lumen. Histologic examination of the anastomoses showed lack of a normal mucosal lining in some examined sections up to two months postsurgery. While mucosal and serosal continuity were eventually reestablished, this was not true of the muscularis, the ends of which were joined by fibrous tissue. Gaps in the staple line and malalignment of staples were present in the animal examined four months after surgery, indicating migration and/or loss of the staples from the anastomosis. The inverting, triangulated staple technique had little or no apparent advantages over previously reported results with similar everting techniques. The severity of adhesions observed with the inverting technique suggests that the adhesions observed with the similar everting technique may not be due solely to the everted nature of the anastomosis.     

Operation technique and healing process of telescopic ileocolostomy in dogs

The healing process of telescopic anastomoses was found in an animal experiment with 12 mongrel dogs. After the division of vessels an ileal segment of different length was invaginated into the lumen of the colon using single-layer interrupted sutures. The following four groups were used: Group A (n = 3): end-to-side ileocolostomy, single-layer interrupted suture (invagination length: 0 mm), survival time: 21 days. Group B (n = 3): invagination length: 20 mm, survival time: 7 days. Group C (n = 3): invagination length: 10 mm, survival time: 21 days. Group D (n = 3): invagination length: 20 mm, survival time: 21 days. At the end of the above survival times the anastomosis area was removed. The bursting pressure was measured and morphological as well as histological examinations were performed. In each case the 0-day look-alikes of anastomoses were performed using the remnant bowels, and bursting pressure measurements were done on these models as well. Anastomosis leakage did not occur. The serosal layer of the intracolonic part of the ileum disappeared during the healing process. The free surface of the intracolonic ileal segment became covered by the sliding mucosa of the colon and the prolapsing mucosa of the ileum. The following could be concluded after the experiments: The inner pressure tolerance of a telescopic ileocolostomy promptly after preparation is better than in case of another single-layer anastomosis. This fact results in increased safety against leakage on the first postoperative days. The inner pressure tolerance of the telescopic ileocolostomy increases during the healing process and it does not depend on the length of the invaginated part (0 day-20 mm: 56 mmHg +/- 6, Group A: 252 +/- 39, Group B: 154 +/- 19, Group C: 249 +/- 20, Group D: 298 +/- 2). There is no difference in pressure tolerance between the telescopic and the end-to-side single-layer interrupted anastomoses after the healing process. The invaginated section within the lumen of the large intestine does not suffer ischaemic or any other kind of damage. This inexpensive and simple anastomosis technique could be useful in the veterinary surgical practice as well.