Comparison of fibrin glue and suture in the healing of teat incisions in lactating goats

The aims of this study were to investigate whether fibrin glue can be used to close experimentally induced incisions of the teat (mammary papillae) in lactating goats and to compare the healing of the glued with the sutured incisions. Four clinically healthy lactating dairy goats, namely 8 mammary papillae were used. After surgical preparation of the papillae, a 3.5 cm long incision of each papilla was made through skin, muscular layer and mucosa into the papillary sinus. The wounds in the right papillae in all goats were closed with U-shaped uninterrupted 00 chromic catgut sutures. The wounds in the left papillae in all goats were closed, using fibrin glue. One incision was seen to be dehisced and fistulous one day after in fibrin glued teats. The animals were slaughtered 8 days after surgical manipulation. The mammary papillae were removed and examined in the viewpoint on gross and microscopic findings. The healing of wounds was slower and feeble in glued mammary papillary incisions, however faster and stronger in sutured incisions on day 8 after operations. But, available outcomes like less tissue thickness and positive cosmetic results could be obtained byfibrin glue used on mammary papillary incisions, which are very important for teats to be milked by hand and milking machine. Results suggest that it is advisable to use only one or two simple interrupted sutures in teat incisions glued with fibrin to prevent the dehiscence but with a more reliable healing than the sutured incisions.

Factors affecting outcome of extensor tendon lacerations in the distal limb of horses. A retrospective study of 156 cases (1994-2003)

Distal limb lacerations are common injuries in horses, with a better prognosis reported for extensor tendons lacerations compared to flexor tendons lacerations. The objective of the present study was to determine the influence of type and location of injury, modalities of treatment and post surgical complications on the outcome of extensor tendon lacerations. The medical records of 156 horses surgically treated for extensor tendon lacerations over a 10-year period were analysed retrospectively. Information was obtained for 124 horses with a minimum of 18 months follow-up. Statistical analysis was performed on 129 horses (five horses were euthanatized during hospitalization) in order to determine factors affecting outcome. Seventy-four percent of the horses returned to soundness, 17% had moderate gait impairment and 9% remained lame. Approximately 60% of the sports horses returned to an equal or higher level of performance, and 17.5% returned to a lower level. In the multivariate statistical analysis, the only significant factor that favourably influenced outcome was complete suture of the wound. A significant association could not be detected between outcome and absence of a functional extensor tendon, The most important post-surgical complication was extensive scarring of the wound. The present results report outcome of extensor tendon lacerations in a large number of horses and outline the importance of primary wound healing in order to avoid major scarring with potential functional consequences.

Surgical Stapling Devices in Veterinary Medicine: A Review

OBJECTIVES

To review indications, benefits, and complications of surgical stapling in animals.

STUDY DESIGN

Literature review.

RESULTS

Benefits and complications of surgical stapling depend on the procedure performed. Use of surgical staplers does not improve wound strength but may decrease surgical time.

CLINICAL RELEVANCE

In patients at significant risk for intraoperative contamination or morbidity from prolonged anesthesia time, use of stapling devices should be considered.

Rectovaginal fistula following colectomy with an end-to-end anastomosis stapler for a colorectal adenocarcinoma

An 11-year-old, female neutered Labrador retriever was presented with a micro-invasive differentiated papillar adenocarcinoma at the colorectal junction. A colorectal end-to-end anastomosis stapler device was used to perform resection and anastomosis using a transanal technique. A rectovaginal fistula was diagnosed two days later. An exploratory laparotomy was conducted and the fistula was identified and closed. Early dehiscence of the colon was also suspected and another colorectal anastomosis was performed using a manual technique. Comparison to a conventional manual technique of intestinal surgery showed that the use of an automatic staple device was quicker and easier. To the authors' knowledge, this is the first report of a rectovaginal fistula occurring after end-to-end anastomosis stapler colorectal resection-anastomosis in the dog. To minimise the risk of this potential complication associated with the limited surgical visibility, adequate tissue retraction and inspection of the anastomosis site are essential.

In Vitro Bursting Pressures of Jejunal Enterotomy Closures in Llamas

OBJECTIVE

To evaluate closure strength (in vitro bursting pressure) of jejunal enterotomies in llamas.

STUDY DESIGN

In vitro experimental study.

SAMPLE POPULATION

Jejunal specimens (n=72) from 6 llamas.

METHODS

Differences in bursting pressures and luminal diameters were compared between 2 layer enterotomy closures with an initial full thickness simple continuous pattern oversewn with either a continuous Lembert or Cushing suture pattern using 3 sizes (2-0, 3-0, 4-0) of polyglactin 910 and polydioxanone.

RESULTS

Bursting pressures were significantly higher for enterotomies closed with polydioxanone than polyglactin 910, independent of suture size, but there was no difference between Lembert and Cushing oversew patterns. Use of a Lembert pattern reduced intestinal diameter more than a Cushing pattern regardless of suture material or size.

CONCLUSIONS

Although polydioxanone resisted higher bursting pressures than polyglactin 910, both suture materials should be considered satisfactory for jejunal enterotomy closure in llamas based on typical intraluminal pressures expected in clinical patients. The optimal oversew pattern may be continuous Cushing to maximize the luminal diameter in small intestinal enterotomy closures.

CLINICAL RELEVANCE

In vitro bursting pressures may help to predict which enterotomy sites would leak post-operatively, although further studies are necessary to determine the outcome in clinical patients.

An In Vitro Comparison of Two Suture Intervals Using Braided Absorbable Loop Suture in the Equine Linea Alba

OBJECTIVE

To compare bursting strength and failure modes of ventral median abdominal incisions closed with loop suture in a simple continuous pattern using two different suture-bite intervals.

STUDY DESIGN

In vitro experiment.

SAMPLE POPULATION

Equine cadavers (n=14; weighing >318 kg; postmortem interval <2 hours).

METHODS

A template was used to make a 25 cm incision with suture interval and bite size of either 1.0 cm x 1.5 cm or 1.5 cm x 1.5 cm. A 200 L polyurethane bladder was inserted within the abdomen and insufflated to create abdominal wall tension. Celiotomies were closed with a #2 braided lactomer 9-1 continuous pattern with a loop suture. Deviation from the linea, closure time (minutes), total suture length (cm), suture length to wound ratio (SL:WL), bursting pressure (mm Hg), and failure modes (fascial or suture) were compared between groups using a Mann-Whitney U test. Significance was set at P<.05.

RESULTS

No significant differences were identified between closing time, total suture length used, SL:WL, bursting pressure, or failure mode. Fascial failure was the main failure mode for both techniques; suture failure occurred rarely and knot failure did not occur.

CONCLUSION

Based on the overall bursting pressure and failure mode, #2 braided lactomer loop suture placed in a continuous pattern should provide sufficient security for closure of the equine linea alba during recovery and the immediate postoperative period.

CLINICAL RELEVANCE

Although there were no significant differences in the 2 patterns evaluated, the 1.5 cm x 1.5 cm pattern may have potential advantages for closure time, less total suture remaining in the wound, and strength.

Comparison of a suture anchor and a toggle rod for use in toggle pin fixation of coxofemoral luxations

The mechanical characteristics of toggle rods and Bone Biter anchors inserted through the medial acetabular wall for toggle pin repair of coxofemoral luxations were compared in 16 canine cadaver pelves. No differences were detected in maximum load to failure, displacement at failure, or energy to failure between the two constructs. Toggle rod constructs failed primarily by breakage of the suture at the rod eyelet. All of the Bone Biter anchor constructs failed when the anchors pulled through the medial acetabular wall.

A Mechanical Study of Ligature Security of Commercially Available Pre-Tied Ligatures Versus Hand Tied Ligatures for Use in Equine Laparoscopy

OBJECTIVE

To determine a hand-tied ligature knot configuration, suture size, and suture type that would be an acceptable substitute to commercially available ligature knots for use in equine laparoscopic surgery.

STUDY DESIGN

Three-factor ANOVA with the fixed effects being suture type, suture size, and knot type. The dependent variable was ligature security (load to failure).

METHODS

Commercially available Endoloop and 4 hand-tied slipknot ligatures were compared with a 4-layer square knot. The hand tied ligature knots tested were the 4S modified Roeder knot, the Brooks knot, the modified Roeder knot, and the Weston knot. Two suture sizes (0, 2) of each of 2 suture types (polydioxanone, polyglactin 910) were tested with each hand tied knot. Two types (polydioxanone, polyglactin 910) of size 0 Endoloop were tested. Twenty repetitions of each knot suture type were tested for force to yield on a materials testing machine. Statistical analysis consisted of a 3-way ANOVA with individual comparisons made using the Bonferroni method. Significance was P< or = .05.

RESULTS

Only the 4S modified Roeder knot in 2 polydioxanone (103 N) was comparable with the breaking strength of the square knots (157 N). All other knot suture combinations tested were significantly weaker than the square knot (range, 2-18 N).

CONCLUSION

For equine laparoscopy, a 2 polydioxanone 4S modified Roeder knot would be an acceptable alternative to the commercially available Endoloop.

CLINICAL RELEVANCE

Laparoscopic slip knots are commonly used in equine laparoscopic surgery. Various knot configuration and suture size and type combinations will affect the security of the slip knot.

In Vitro Comparison of Two Techniques for Suture Prosthesis Placement in the Muscular Process of the Equine Arytenoid Cartilage

OBJECTIVE

To compare in vitro the load necessary for a partial and complete rupture of the muscular process arytenoid cartilage when a suture prosthesis is positioned by a bone trocar versus a trocar point needle and to compare failure mode.

STUDY DESIGN

Experimental using cadaver specimens.

SAMPLE POPULATION

Larynges from 18 Thoroughbred race horses, aged 2-20 years.

METHODS

Arytenoid cartilages were separated randomly into 2 groups: group 1-suture prosthesis inserted directly through the muscular process using a curved trocar point needle and group 2-suture passed through a hole predrilled with a 3 mm bone trocar. Distracting force (constant rate, 1 mm/s) was applied to the suture until failure of the muscular process. Partial failure load, maximum load at complete failure, and force-time curve were recorded. Each arytenoid cartilage was examined, radiographed, and classified as having a linear or curved failure plane.

RESULTS

No significant differences in mechanical test variables were detected. Failure mode followed the fissures occurring at the beginning of failure and then followed the tension axis. Significantly more linear failures occurred in group 2 (trocar) and more curved failures occurred in group 1 (needle).

CONCLUSION

Use of a bone trocar for tunneling through the muscular process may reduce fissure formation.

CLINICAL RELEVANCE

Use of bone trocar to create a hole in the muscular process of the arytenoid cartilage for suture passage in laryngoplasty may reduce fissure formation and decrease the risk of cartilage failure from suture pullout.

Ex Vivo Strength Comparison of Bioabsorbable Tendon Plates and Bioabsorbable Suture in a 3-Loop Pulley Pattern for Repair of Transected Flexor Tendons from Horse Cadavers

OBJECTIVE

To test the failure strength and energy of 2 bioabsorbable implants applied to transected deep digital flexor tendons (DDFT) from adult horses.

STUDY DESIGN

Ex vivo biomechanical experiment.

SAMPLE POPULATION

Twelve pairs of deep digital flexor tendons harvested from the forelimbs of fresh equine cadavers.

METHODS

Poly-L-lactic acid tendon plates were custom manufactured for application to the cylindrical surface of an adult equine deep digital flexor tendon. Twelve pairs of DDFTs were transected 2 cm distal to the insertion of the distal check ligament of the deep digital flexor tendon. One tendon of each pair was randomly selected for repair with a biodegradable plate or a 3-loop pulley method. Size 2 polydioxanone suture was used in both repairs. Repairs were tested in tension to failure, with peak force (PF) and total energy (TE) at repair failure recorded in Newtons (N) and Joules (J), respectively. A paired t-test was used for statistical evaluation with a significant level set at P< or = .05.

RESULTS

Mean+/-SD PF for failure of plated tendons (1507.08+/-184.34 N) was significantly greater than for sutured tendons (460.86+/-60.93 N). TE was also significantly greater for failure of plated tendons versus sutured tendons.

CONCLUSIONS

Plate fixation of transected cadaver DDFTs appear to have superior immediate failure strength than 3-loop pulley repairs.

CLINICAL RELEVANCE

Whereas in vivo testing is required, a bioabsorbable tendon plate may provide initial increased strength to support tendon healing and decrease external coaptation requirements.

Comparison of gross and histologic tissue responses of skin incisions closed by use of absorbable subcuticular staples, cutaneous metal staples, and polyglactin 910 suture in pigs

OBJECTIVE

To assess gross and histologic tissue responses of skin incisions closed by use of absorbable subcuticular staples, cutaneous metal staples, and polyglactin 910 suture in pigs.

ANIMALS

8 purpose-bred disease-free pigs.

PROCEDURE

Pigs were randomly allocated to 1 of 4 groups from which tissues were collected after death on postoperative days (PODs) 7, 14, 21, or 42. In each pig, 4 incisions were made; 1 was closed subcuticularly with 3-0 polyglactin 910 suture, 1 was closed with metal staples, and 2 were closed with absorbable subcuticular staples. Incision sites were grossly evaluated every 3 days after closure. At necropsy, incision sites and surrounding tissues were examined histologically; a histopathologic scoring system was used to quantitate healing and tissue response directed against the closure material.

RESULTS

Postoperatively, the metal staples induced a severe inflammatory response, compared with minimal inflammation associated with the suture or absorbable subcuticular staples. Histologic evaluation of incisions on PODs 7, 14, and 21 revealed less severe inflammation associated with absorbable subcuticular staples than that associated with the other materials.

CONCLUSIONS AND CLINICAL RELEVANCE

Results indicated that absorbable subcuticular staples induced a less severe inflammatory response in the early stages of healing in pigs, compared with other commonly used methods of wound closure. Use of absorbable staples potentially combines the benefits of subcuticular closure with the speed and precision of staple placement.

Costs and complications of equine castration: a UK practice-based study comparing 'standing nonsutured' and 'recumbent sutured' techniques

REASONS FOR PERFORMING STUDY

Clinicians are often asked to guide owners and trainers over the relative advantages and disadvantages of equine castration performed in either the standing horse with an open unsutured scrotal wound with healing by second intention, or a recumbent horse under general anaesthesia in aseptic conditions, with sutured scrotal skin allowing primary wound closure.

OBJECTIVES

To identify types and frequency of complications following the 2 differing approaches, and to compare the financial cost associated with each procedure, based on practice charges.

METHODS

Veterinary expenses of 217 horses castrated by a Newmarket equine veterinary practice over an 18-month period were analysed. Of these, Group 1 (n = 121) were castrated standing and nonsutured by one of 2 ambulatory clinicians and Group 2 (n = 96) castrated in recumbency, in aseptic equine hospital conditions.

RESULTS

Group 1 had a complication prevalence of 22% with no mortalities, and Group 2 a significantly lower complication prevalence of 6% (P = 0.001) with a mortality rate of 1%. The financial cost of Group 1, without complications, was approximately one-third of the cost of uncomplicated Group 2. However, the cost of Group 1 with complications increased to approximately two-thirds of the cost of an uncomplicated Group 2 castration.

CONCLUSIONS

Even though the complication prevalence for Group 1 castrations leaving an open scrotal wound was significantly higher than for a recumbent horse with a sutured scrotal wound in a hospital, the average cost of Group 1 was still less, even taking into account the additional follow-up costs associated with treating such complications.

POTENTIAL RELEVANCE

This report provides a benchmark for the outcome of 2 methods of castration based on a database obtained from particular circumstances within the practice involved. Further studies are required to corroborate and take into account future development in surgical and anaesthetic techniques.

In Vitro Evaluation of the 18 and 36 kg Securos Cranial Cruciate Ligament Repair Systemtm

OBJECTIVE

To evaluate the mechanical properties of the 18 and 36 kg Securos Cranial Cruciate Ligament Repair System.

STUDY DESIGN

In vitro mechanical evaluation.

SAMPLE POPULATION

Loop constructs of 18, 27, and 36 kilogram test (kgt) nylon leader line (NLL) secured with Securos crimp-clamps (SCC, n=40 per NLL test weight) or by a clamped square knot (CSK; n=40/NLL test weight).

METHODS

The 36 kg SCC were used for the 27 and 36 kgt NLL, and 18 kg SCC were used for the 18 kgt NLL. Loop constructs were mounted on a material testing machine, and distracted at 500 mm/min for static tests, and for cyclic tests at 500 mm/min to a distraction limit of 6 mm (18 kgt) or 7.5 mm (27 and 36 kgt) for 49 cycles, until failure. Constructs were tested at 20 degrees C except for 1 group of 27 kgt CSK loops tested at 40 degrees C. Load at failure, elongation, and stiffness was recorded and compared between groups under static or cyclic testing conditions.

RESULTS

All 27 and 36 kgt loops failed by disruption of NLL contained within the knot or crimp-clamp, whereas 18 kgt SCC loops failed by the NLL pulling through the crimp-clamp. The 18 kg SCC loops had considerable variability in ultimate load and elongation (coefficient of variation 29.6% and 18.3%, respectively). There was no significant difference in elongation between 27.3 kgt CSK loops tested at 20 degrees C and 40 degrees C. Generally, in both static and cyclic testing, SCC constructs formed with 27.3 or 36.4 kgt NLL performed as well or better than CSK constructs, resulting in loops that were strong, underwent minimal elongation, and had high stiffness.

CONCLUSION

The results support use of the 36 kg Securos system but not the 18 kg Securos system (with the clamp and crimping device used). The significantly lower load required for failure, slippage through the clamp, and substantial variability suggested that the crimp tube diameter or the crimping device tested may be inappropriate for use with 18 kgt NLL.

CLINICAL RELEVANCE

Surgeons should be aware that crimp-clamp design is important in controlling suture slippage or breakage within the clamp, and that novel systems should undergo mechanical testing with the size suture material they are intended to secure before clinical use.

Bursting Tension of Medium and Large Canine Arteries Sealed with Ultrasonic Energy or Suture Ligation

OBJECTIVE

To compare bursting tension of arteries > or =3 mm in diameter sealed with ultrasonic energy (UE) with arteries ligated with suture.

STUDY DESIGN

Experimental, nested factorial design.

SAMPLE POPULATION

Vascular segments from canine cadavers.

METHODS

Arterial segments (12) were collected from each of 16 canine cadavers and equally divided into 2 groups based on vessel diameter (medium, 3.0- < 4.5 mm; large, 4.5 - < or =6.0 mm). Arterial specimens (3) from each group were sealed with either UE (Harmonic Scalpel, HS, power level 3) or suture ligation. The mean bursting pressure and tension were determined and compared.

RESULTS

Bursting tension was significantly higher (P< .0001) for sutured arteries than UE-occluded arteries, irrespective of size. Bursting tension was significantly higher (P=.0013) for medium than large UE-occluded arteries, whereas there was no difference associated with size for ligated arteries. UE energy failed to seal 1 medium artery and 7 large arteries. Compared with normal blood pressure, bursting pressures were 3.5 times greater for sutured arteries irrespective of size, 1.8 times greater for medium UE-occluded arteries, and approached normal blood pressure for large UE-occluded arteries.

CONCLUSION

At the power level tested, UE should not be used to seal arteries > 4.5 mm in diameter. Suture provided an optimal seal for arteries < or =6.0 mm in diameter.

CLINICAL RELEVANCE

Use of UE to occlude arteries during laparoscopic surgery is advantageous because only 1 instrument is required to simultaneously cut and coagulate tissue, but care should be exercised where large arteries might be encountered.

Principles of early wound management

The equine practitioner can positively influence wound healing by dispensing appropriate treatment in the first few hours after injury. Positive actions in the early period include hemostasis, meticulous cleansing and debridement of the wound, the use of effective but nonirritating products to disinfect the wound, closure (if indicated)with minimal tension on the suture line, the judicious use of drains,and ensuring adequate tetanus protection. Furthermore, a thorough assessment of the wound and the patient in the initial period after trauma provides pertinent information on prognosis. Finally,good communication and cooperation among all involved parties are necessary to ensure that everyone understands the factors involved and the potential for a successful outcome.

Foreign body attachment to polypropylene suture material extruded into the small intestinal lumen after enteric closure in three dogs

Three dogs in which polypropylene suture material was used to close an enteric surgery site in a continuous pattern were evaluated at a later date because of recurrence of signs of intestinal disease. Surgery in each dog revealed that the suture material had been extruded into the lumen of the intestine and acted as a site for attachment of a foreign body. The nonabsorbable nature of polypropylene and its use in a continuous pattern are possible explanations for this complication. Polydioxanone or poliglecaprone 25 may be suitable alternatives to polypropylene for use in a continuous pattern for closure of small intestinal surgery sites.

An In Vitro Biomechanical Comparison of the Breaking Strength and Stiffness of Polydioxanone (Sizes 2, 7) and Polyglactin 910 (Sizes 3, 6) in the Equine Linea Alba

OBJECTIVE

To determine failure strength, stiffness, and failure mode of 4 suture materials in equine linea alba.

STUDY DESIGN

Randomized complete block design.

SAMPLE POPULATION

Linea albas collected from 12 adult horses (mean weight, 475 kg; mean age, 10 years).

METHODS

The ventral abdominal fascia, including the linea alba, was collected and bisected along the linea alba into right and left halves. Each half was divided into four, 5-cm sections extending from the umbilicus cranially, and randomly assigned to 1 of 4 suture materials: 2 polydioxanone (2 PD), 3 polyglactin 910 (3 PG), 6 polyglactin 910 (6 PG), and 7 polydioxanone (7 PD). A single cycle to failure test was performed on each specimen at a distraction rate of 100 mm/min. Differences in failure strength and stiffness for the materials were evaluated using a mixed linear model with significance set at P<.05.

RESULTS

In 94 of 96 test sections, constructs failed by suture failure. There were significant differences in failure strength (P<.0001) and stiffness (P<.001) among the suture/tissue constructs. 7 PD had the highest breaking strength (316.8 N) followed by 6 PG (281.3 N), 3 PG (229.9 N), and 2 PD (193.0 N). Six PG had the largest stiffness (14 N/mm) followed by 3 PG (12.7 N/mm), 7 PD (10.1 N/mm), and 2 PD (7.2 N/mm). Suture breaking strength and stiffness were not affected by linea or fascia thickness, individual horse, half of the linea alba, or abdominal wall position. Eighty-five (90.4%) suture loops failed adjacent the knot.

CONCLUSIONS

When tested in single cycle to failure, suture material was more likely to fail than the linea alba. Larger suture materials had higher breaking strengths than smaller suture materials and stiffness was also affected by suture material and size.

CLINICAL RELEVANCE

Given its high initial breaking strength and its relatively longer in vivo strength retention, 7 PD seems an appropriate choice of suture material for closure of the equine linea alba when maximal short-term failure strength is desired.

Clinical Evaluation of Random Skin Flaps Based on the Subdermal Plexus Secured with Sutures or Sutures and Cyanoacrylate Adhesive for Reconstructive Surgery in Dogs

OBJECTIVE

To evaluate the use of subdermal plexus skin flaps for closing defects after excision of cutaneous and subcutaneous tumors in dogs and to compare outcome of flaps secured with sutures and those secured with butyl-cyanoacrylate and intermittent sutures.

STUDY DESIGN

Clinical study.

ANIMALS

Fifteen dogs.

METHODS

After excision of cutaneous or subcutaneous tumors the skin defect was reconstructed by random flaps based on the subdermal plexus. Flap skin edges were apposed with simple interrupted 4-0 monofilament nylon sutures (group 1; 5 dogs) or nylon sutures alternated with butyl-cyanoacrylate adhesive (group 2; 10 dogs). Flaps were evaluated every 48 hours when bandages were changed, until complete healing.

RESULTS

Random flaps based on the subdermal plexus were effectively used to close wound defects; mean flap survival was 89%. Partial flap necrosis occurred in 4 dogs. Wound margins apposed with butyl-cyanoacrylate had thinner and more esthetic scars than sutured margins.

CONCLUSION

Random flaps based on the subdermal plexus proved to be versatile for covering limb wounds after excision of cutaneous or subcutaneous tumors. Mean survival rate was comparable to that reported for axial pattern flaps. Butyl-cyanoacrylate adhesive was easy to apply, allowed accurate margin apposition with good cosmetic outcome and reduced sutures needed.

CLINICAL RELEVANCE

Cyanoacrylate adhesive should be considered in lieu of suture closure to secure random skin flaps based on the subdermal plexus in dogs.

Methods of Gradual Vascular Occlusion and Their Applications in Treatment of Congenital Portosystemic Shunts in Dogs: A Review

OBJECTIVE

To provide a comprehensive review of the experimental and clinical data related to gradual vascular occlusion of congenital portosystemic shunts (CPS) in dogs.

STUDY DESIGN

Literature review.

METHODS

PubMed literature search (1966-2004).

RESULTS

Surgical intervention and complete vascular occlusion have been recommended for CPS therapy in dogs; however, acute complete ligation of CPS is often associated with life-threatening portal hypertension. Recently, several investigators have attempted to reduce the risk of postoperative portal hypertension by using gradual vascular occlusion. Successful vascular occlusion has been achieved using partial ligation with silk suture, ameroid constrictors, cellophane bands, thrombogenic coils and hydraulic vascular occluders. Objective comparisons of the reliability and rate of vascular occlusion produced by each of these methods have been limited by differences in experimental models and a lack of definitive follow up evaluation in some clinical studies.

CONCLUSIONS

Gradual vascular occlusion is widely used in the clinical treatment of CPS in dogs. Objective evaluation of the experimental and clinical data on each of the techniques for gradual vascular occlusion is necessary for informed clinical practice and for the planning of future research into this important area.

CLINICAL RELEVANCE

Even from the limited data available, it is clear that the ideal method for gradual vascular occlusion of CPS has yet to be identified.

[Rectal tears in the horse: two case reports]

Rectal tears occur incidentally and often have a poor prognosis. Early recognition of the problem and adequate therapy determine the outcome. The history, clinical examination, therapy, and outcome of two horses with grade IIIb and grade IV rectal tears are discussed.

A Comparison of Knot Security of Commonly Used Hand-Tied Laparoscopic Slipknots

OBJECTIVE

To compare the peak force required for failure of hand-tied laparoscopic slipknot ligatures.

STUDY DESIGN

In vitro mechanical evaluation of suture material/knot combinations.

SAMPLE POPULATION

Four hand-tied laparoscopic slipknots were studied. Three suture materials and 2 suture sizes were evaluated. Twenty samples of each group were tested, for a total of 400 samples.

METHODS

The 4S modified Roeder, modified Roeder, and Weston and Brooks laparoscopic slipknots using 0 polyglyconate, 0 polyglycolic acid, 1 polyglyconate, and 1 polydioxanone (PDS) were tested. A vertical distracting force (5 mm/s) was applied until failure. Mean peak force to failure was obtained for each suture material, size, and knot combination.

RESULTS

Mean (+/-SEM) peak force to failure of hand-tied ligatures ranged from 156.8+/-9.1 N to 4.8+/-.4 N. The 4S-modified Roeder had the highest mean peak force to failure. Ligatures tied with polyglyconate and size 1 suture had the highest mean peak force to failure.

CONCLUSIONS

The 4S-modified Roeder was significantly and consistently stronger than the other slipknots. Polyglyconate was superior to other suture materials. The 1 polyglyconate had the highest mean peak force to failure followed by 0 polyglyconate that exceeded the 1PDS.

CLINICAL RELEVANCE

The 4S-modified Roeder slipknot using 1 polyglyconate has the greatest breaking strength of sutures tested and should be considered when performing laparoscopic ligatures.

Postoperative Assessment of Surgical Clip Position in 16 Dogs With Cancer: A Pilot Study

Metallic hemoclips or surgical staples were inserted in 16 tumor-bearing dogs at the time of surgical resection of the tumor. Orthogonal radiographs were taken immediately postoperatively and after wound healing to visualize the location and number of hemoclips or metallic staples. A shift in hemoclip/staple position was identified in nine dogs, mainly from positioning during radiography. In three dogs, an absolute shift in marker position was identified. Based on this study, it appears that the placement of surgical clips is potentially useful in identifying the tumor bed, which may be of benefit in establishing radiation treatment fields.