Partial Maxillectomy and Premaxillectomy in the Treatment of Oral Neoplasia in the Dog and Cat

Partial maxillectomies were performed in 17 dogs and three cats to accomplish wide excision of oral tumors. The extent of the maxillectomy was dependent on tumor type, location, size, and invasiveness as determined by clinical and radiographic examination and incisional biopsy. The tumor and involved portions of adjacent facial bones, most commonly the maxillary and incisive bones, were removed. The resulting oronasal defect was closed by suturing a labial mucosal flap based on the lip margin to the hard palate mucoperiosteum. The major postoperative complication was partial suture line dehiscence, which occurred in three dogs. All four dogs with benign tumors were free of disease 7 to 34 months postoperatively (median 21.5 months). Of the 13 dogs treated for malignant neoplasia, seven were tumor-free at follow-up times ranging from 3 to 31 months (median 12 months). Five dogs with malignant tumors developed local recurrence 1 week to 10 months postoperatively (median 4.5 months). One cat with a benign tumor and two with malignant tumors were tumor-free at follow-up times of 7, 24, and 27 months. Partial maxillectomy can be effective in treating both benign and malignant oral tumors in dogs and cats.     

Esophagotomy Closure in the Dog A Comparison of a Double-Layer Appositional and Two Single-Layer Appositional Techniques

Esophagotomies were performed on 36 dogs and closed with 3-0 polydioxanone in double-layer simple interrupted, single-layer simple interrupted, or single-layer simple continuous patterns. The operative time was shortest for single-layer simple continuous closure, followed by single-layer simple interrupted and double-layer simple interrupted, respectively. Three dogs with each suture pattern were euthanatized at hours 0 and 1, and days 4 and 28 after surgery. The esophagotomy incisions were subjected to bursting strength testing and examined microscopically. The bursting wall tension was higher for all three suture pattern groups at 28 days than at 0 and 1 hour. The double-layer closure had higher bursting wall tension than the single-layer closures at 0 hour and 4 days. Single-layer simple continuous closure had the lowest bursting wall tension for each time period. Single-layer simple interrupted closure had the highest bursting wall tension at 28 days. Microscopic examination revealed close approximation of tissue planes for the double-layer closure and mucosal ever-sion for the simple interrupted and simple continuous single-layer closures. Healing was superior histologically with the double-layer closure.     

Cholecystoduodenostomy in the Dog Comparison of Two Techniques

A mucosal apposition technique for cholecystoduodenostomy was compared to the cutting suture technique. The mucosal apposition technique was easier to perform, less traumatic, and produced a significantly larger anastomotic opening than the cutting suture technique. Eleven of 12 dogs returned to normal activity within 5 days after the mucosal apposition technique. Six of 12 dogs required 10 to 21 days after the cutting suture technique before regaining normal activity. Healing was similar for both techniques. Aerobic and anaerobic bacteria were cultured from the gallbladders of both groups postoperatively.
Cholecystograms demonstrated rapid drainage of the biliary system following mucosal apposition. Drainage of the biliary system following the cutting suture technique was slower; gallbladders tended to be irregularly shaped and distended.
Gallbladders rapidly filled with contrast material during upper gastrointestinal barium studies following cholecystoduodenostomy by mucosal apposition. Gallbladders filled more slowly and less completely following the cutting suture technique: drainage of refluxed contrast material was delayed in some dogs.
Serum enzyme elevations (SGPT, SAP) and subclinical periportal inflammation and fibrosis were found following both techniques. Peripheral circulating eosinophil counts were significantly higher in dogs following the cutting suture technique.     

Comparison of 5 Surgical Techniques for Partial Liver Lobectomy in the Dog for Intraoperative Blood Loss and Surgical Time

Objective: To compare surgical time and intraoperative blood loss for 5 partial liver lobectomy techniques in the dog. Study Design: Experimental in vivo study. Animals: Dogs (n=10). Methods: Five surgical techniques (SurgiTie^?; LigaSure^?; Ultracision^® Harmonic Scalpel [UAS]; Suction+Clip; Suction+thoracoabdominal stapler [TA]) for partial liver lobectomy in dogs were evaluated and compared for total surgical time and intraoperative blood loss. Body weight, activated clotting time (ACT), heart rate, and intraoperative blood pressure (BP) were recorded. Blood loss was determined by adding the weight of the blood soaked sponges during surgery (1 g=1 mL) to the amount of suctioned blood (mL). Surgical time (in seconds) was determined from the start of the lobectomy until cessation of bleeding from the stump. Mean surgical time and mean blood loss for each technique were compared using a Tukey's multiple comparison test. Results: No significant differences were found between dogs for weight, ACT, heart rate, and intraoperative BP. No complications were seen with the SurgiTie^? technique in 9 of 10 cases. There was no significant difference in surgical time between techniques however there was a significant difference for blood loss; the Suction+Clip method had significantly more blood loss than the other techniques. Conclusions: Skeletonization of the lobar vessels before individually clipping them (Suction+Clip) resulted in a higher blood loss than using Suction+TA, UAS, SurgiTie^? or the LigaSure^? device. The SurgiTie^? appears to be an acceptable method for partial liver lobectomy. Clinical Relevance: Although skeletonization and individually clipping the vessels had the highest blood loss, it still was <7.5% of total blood volume. All 5 techniques should be safe for clinical use in small to medium sized dogs up to 26 kg.     

A Comparison of Two Methods of Partial Pancreatectomy in the Dog

Partial pancreatectomy was performed in 9 dogs by dissection and ligation of the pancreatic ductule and blood vessels, and in 10 dogs by a suture fracture technique. The dogs were evaluated for detrimental effects by (1) monitoring clinical signs and serum amylase and lipase activities and (2) examining the excision sites grossly and histologically at necropsy. There were no clinically apparent detrimental effects with either technique. The suture fracture technique evoked more histologic inflammation than the dissection and ligation technique.     

Tracheal Anastomosis in the Dog Comparison of Two End-to-End Techniques

Two techniques for tracheal resection and anastomosis were performed and compared in 20 normal dogs. In one technique, cartilage rings were split circumferentially, and the split rings were apposed with simple interrupted sutures that penetrated the annular ligament. In the other technique, the annular ligaments were incised and apposed with simple interrupted sutures placed through the annular ligament and around the adjacent ring. Endoscopy and xeroradiography were used to evaluate the anastomotic sites at 1, 2, 4, and 8 weeks postoperatively. Infection, mucus accumulation, coughing, stridor, or anastomotic separations were not seen. Stenosis of the anastomotic site was observed in 80% of the dogs, due to the intraluminal protrusion of epithelialized fibrous connective tissue. The split cartilage technique was easy to perform and resulted in less dorsoventral stenosis than the annular ligament technique.     

Cystotomy Closure: A Comparison of the Strength of Appositional and Inverting Suture Patterns

Dorsal cystotomies were performed in 60 healthy dogs. Twenty bladders were closed with a single-layer interrupted appositional suture pattern, 20 with a two-layer interrupted appositional suture pattern, and 20 with a two-layer continuous inverting suture pattern. Four dogs from each group were euthanatized at hours 0, 3, 12, 18, and 24. Mechanical strength of the cystotomy closures was evaluated by calculating the circular bursting wall tension. The single-layer interrupted appositional suture pattern was as strong as both two-layer suture patterns at hours 3, 12, 18, and 24. The two-layer interrupted appositional suture pattern was as strong as the two-layer continuous inverting suture pattern during the first 24 hours.     

Hepatic Lobectomy in the Dog A Comparison of Stapling and Ligation Techniques

The left lateral hepatic lobe was removed in six dogs with a stapling instrument and in six dogs by blunt dissection and ligation. Both techniques were safe and effective. Lobectomy by dissection and ligation was slower and less complete than by stapling. Major intraoperative or postoperative hemorrhage did not occur with either method. Serum chemistry values were elevated after surgery in all dogs but did not differ significantly between treatment groups. Microscopic hemorrhage, necrosis, and inflammation of the lobectomy site were more pronounced after dissection and ligation than stapling.     

Comparison of Stainless Steel Fascial Staples and Polypropylene Suture Material for Closure of the Linea Alba in Dogs

Five centimeter segments of the linea alba in mature, female, mixed breed dogs were incised and then approximated with either stainless steel fascial staples or size 0 polypropylene suture material. Breaking strength of the linea alba closures was determined at 0 (Phase I, 18 dogs) and at 7,14, and 31 days (Phase II, 18 dogs). Histology and videointeractive planar morphometry were used to evaluate healing of the linea alba. Breaking strength and histologic and morphometric variables were analyzed statistically using analysis of variance in a split plot design. In a clinical trial, 20 cm linea alba incisions were approximated with stainless steel fascial staples after elective ovariohysterectomy in mature, female, mixed breed dogs (Phase III, eight dogs). The dogs were evaluated at 1, 2, 7,14, 31, 90, and 180 days. Linea alba incisions approximated with polypropylene suture material were significantly stronger than linea alba incisions approximated with stainless steel fascial staples on day 0. There was no significant difference between breaking strength values, histologic, and morphometric appearance of linea alba incisions closed with stainless steel fascial staples or polypropylene suture material when compared 7,14, and 31 days after surgery. All of the dogs in the clinical trial appeared to be normal at all evaluation times. Approximation of linea alba incisions with stainless steel fascial staples compares favorably to closure with a simple continuous pattern of polypropylene suture material with regard to breaking strength, clinical, histologic, and morphometric appearance.     

Comparison of Three Skin Preparation Techniques in the Dog Part 1: Experimental Trial

Premeasured, clipped areas of skin on both sides of 30 adult dogs were prepared with povidone-iodine (PI), chlorhexidine gluconate (CG) with a saline rinse, or 4% CG with a 70% isopropyl alcohol rinse. Skin bacteria were quantified with Replicating Organism Detection and Counting (RODAC) plates and cultured for identification before, immediately after, and 1 hour after skin preparation. The percentages of bacterial reduction immediately and at hour 1 and the percentages of negative cultures, cultures with more than five colony-forming units (CFUs), and skin reactions were analyzed by analysis of variance and chi-square. The percentage of reduction in skin bacteria for all techniques was significant and comparable with that reported in humans. There were no significant differences between PI and CG results except that acute contact dermatitis was observed more frequently after skin preparation with PI. The authors conclude that for similar application times, PI and 4% CG rinsed with saline or 70% isopropyl alcohol are equally effective for up to 1 hour in the preoperative skin preparation of dogs.     

Knot Security of Suture Materials

The knot security of chromic gut, polyglycolic acid, polyglactin 910, polydioxanone, polypropylene, and monofilament nylon size 2-0 suture materials were tested biomechanically in vitro. Twenty reproducible knots were tied and incubated in canine serum at 37 degrees for 24 hours before testing. A "secure knot" was defined as a knot that, when tested to failure, broke rather than untied by slippage. The minimum number of throws necessary to make a secure, snug (1500 g tension) square knot was three for gut, polyglycolic acid, polyglactin 910, and polypropylene and four for polydioxanone and nylon. All throws including the first were counted. With all suture materials tested, surgeon's knots were as secure as square knots. Only gut, polyglycolic acid, and polydioxanone granny knots were as secure as square knots; no loosely tied (500 g tension) asymmetric square knots were as secure as snug square knots, and only polydioxanone and polypropylene loose square knots were as secure as snug square knots. Square knots used to start a continuous pattern required one additional throw with gut, polydioxanone, and nylon. Square knots used to end a continuous pattern required two to three additional throws with all materials tested.     

Suture Materials and Suture Selection for Use in Exotic Pet Surgical Procedures

Exotic animals are becoming increasingly popular and more exotic pet owners are seeking veterinary care. This has led to a demand for properly trained veterinarians who are capable of providing quality, up-to-date medical and surgical treatments. Many surgeries are now performed on exotic pets, and selection of the appropriate suture material is an important part of the treatment protocol. An understanding of different available suture materials, healing times of different tissues, and knowledge of different anatomic and physiologic characteristics in different species is important in the selection of the most appropriate suture material. This review will summarize important aspects of suture selection in exotic animals.     

Biomechanical Evaluation of Gastropexy Techniques in the Dog

The relative strength of adhesions created by three different gastropexy techniques in dogs was evaluated two and six months following surgery. Tube gastrostomy formed a stronger adhesion (p>.001) when compared with simple gastropexy and permanent gastropexy two months after operation. In a smaller number of animals examined at six months, no difference in strength was noted between permanent gastropexy and tube gastrostomy.     

Partial Arytenoidectomy in the Horse with and without Mucosal Closure

Left-sided partial arytenoidectomy was performed in eight horses to evaluate healing. Four horses underwent conventional partial arytenoidectomy with suture apposition of the mucosa. In four horses, most of the arytenoid cartilage, including overlying mucosa, vocal fold, and laryngeal saccule, were excised en bloc without mucosal closure. The horses were monitored clinically by endoscopic examination. One horse from each group was euthanatized at weeks 2, 4, 8, and 16. Complete necropsies with gross and histologic examination of the arytenoidectomy sites were performed. Postoperative complications such as coughing, dysphagia, and aspiration pneumonia were not encountered and problems with wound healing were minimal in both groups. The defect created by partial arytenoidectomy without mucosal closure initially filled to the level of the luminal surface with granulation tissue, with a gradual transition to mature fibrous connective tissue. Grossly, the defect appeared to be healed and was completely epithelialized by week 16 without apparent narrowing of the laryngeal lumen. Partial arytenoidectomy sites with mucosal closure healed in a similar pattern by week 8. Partial dehiscence of the dorsal portion of the sutured mucosa occurred in three horses.     

Considerations for Selection of Suture Materials

The selection of a suture material, in the past, was based primarily on habit, guesswork and physical properties. This is understandable because there was a limited number of materials to select from and the interaction of suture material with tissues was not understood.     

A Comparison of Three Techniques for Closure of Pelvic Flexure Enterotomies in Normal Equine Colon

Six enterotomies 3 cm long, spaced at 3 cm intervals, were made in the antimesenteric border of the pelvic flexure of the ascending colon in five adult horses. Ten incisions each were sutured with a Utrecht pattern (single layer), a full-thickness simple continuous oversewn with a Cushing pattern (two layer), and a mucosal simple continuous with a seromuscular simple continuous oversewn with a Cushing pattern (three layer). In all horses, chromic gut and polyglactin 910 were each used once for each pattern. On day 6, the pelvic flexure was excised and the colonic vessels were injected with a radio-opaque mass. Sections of each enterotomy were studied by light microscopy and high detail radiography. The single-layer closure led to serosa-to-mucosa healing and a thin bowel wall, and the three-layer closure resulted in distortion of the bowel wall by hematoma formation and submucosal contamination with ingesta. The two-layer closure resulted in good alignment and improved healing. There was less inflammatory reaction with polyglactin 910 than with chromic gut.     

Low-Intensity Laser Light-Induced Closure of a Chronic Wound in a Dog

OBJECTIVE: To describe the application of low-intensity laser light for treatment of a chronic, full-thickness skin wound in a dog. STUDY DESIGN: Case report. ANIMALS: An 8-year old, castrated Whippet. METHODS: The wound was irradiated on the awake patient with 630 nM wavelength, nonthermal red light once daily for 4 consecutive days. Changes in wound surface area were measured by computer analysis of digital images of the wound. RESULTS: The wound diminished in size during the course of laser treatments and was completely healed by day 21. No post-treatment complications occurred. CONCLUSIONS: Low-intensity laser light may be useful for treatment of chronic skin wounds in dogs.     

Effects of Nylon and Polyglactin 910 Suture Material on Perilimbal Corneal Wound Healing in the Dog

The effects of fine suture materials on corneal wound healing in the dog were studied. In 20 dogs, standardized perforating perilimbal clear corneal wounds were made and closed with either monofilament Polyglactin 910 or nylon. Five dogs each were euthanized 8,12,16, and 21 days postoperatively. Results of gross, biomicroscopic, and histologic examinations at 8,12,16, and 21 days showed nylon and Polyglactin 910 to cause similar inflammatory responses. Epithelialization and suppuration around the suture tracts were observed more frequently when Polyglactin 910 was used. Both materials were associated with a foreign body (granulomatous) response. There was no loss of wound integrity with either material. Strengths of the incised corneal tissues with and without the sutures intact were determined. At day 16 postsurgery, there was a statistically significant difference in tissue strengths between cases in which sutures were and were not intact. This difference was not apparent at 21 days postsurgery, which suggested that the suture dependent phase ends between the 16th and 21st postsurgical days. In addition, at day 16 there was no statistical difference between the tissue strength of wounds sutured with nylon or Polyglactin 910. Corneal suture materials studied should remain in place for at least 16 days, and absorbable material is only appropriate if it retains tensile strength for 16 days.