Standing rectal and tail surgery.

A variety of rectal, perirectal, and coccygeal surgeries can be performed in the standing equine patient if appropriate chemical and physical restraints are available and adequate regional anesthesia can be achieved. Some rectal tears and most rectal prolapses, mass lesions, perirectal abscesses, rectal biopsies, and selected injuries of the tail can be managed without prohibitive difficulty. Severe injuries that compromise the small colon cranial to the peritoneal reflection may require flank laparotomy, midline celiotomy, or humane euthanasia to manage the disease process effectively and appropriately. The foremost perioperative consideration beyond the use of effective restraint is the management of tenesmus in horses with rectal tears or prolapses. Medications to control bowel motility, epidural anesthesia, antiinflammatory analgesics, and topical compounds adequate to soothe and lubricate inflamed rectal tissues are an important adjunctive therapy in the aftercare of these surgical patients. Of nearly equal importance is the requirement that a loose fecal consistency be maintained with laxative diets, psyllium, and mineral oil. Failure to maintain a loose consistency of stool after treatment of these conditions may lead to rectal impaction or incisional dehiscence and surgical failure.     

Nonstrangulated colonic displacement in horses

Nonstrangulated colonic displacement was diagnosed by exploratory celiotomy in 32 horses with acute abdominal pain. Clinical signs progressed slowly and included evidence of mild to moderate abdominal pain, good cardiovascular status, reduced intestinal sounds, and normal peritoneal fluid, and resembled those of colonic impaction. In most horses, rectal palpation supported a diagnosis of colonic obstruction but not a diagnosis of colonic impaction.     

Temporary indwelling rectal liner for use in horses with rectal tears

A temporary indwelling liner was surgically installed in 17 horses with grade III or grade IV rectal tears. The rectal tears of 9 of the horses healed. The remaining 8 horses developed peritonitis as a result of peritoneal contamination before surgery, a change in grade of the tear, or material failure.     

Surgical technique to repair grade IV rectal tears in post-parturient mares

Objective— To describe a surgical technique for repair of grade IV rectal tears after parturition in mares and to report outcome.
Study Design— Clinical report.
Animals— Horses (n=6) with grade IV rectal tears.
Methods— Mares were sedated and restrained in standing stocks. After caudal anesthesia and evacuation of feces from the rectum, the perineal region was aseptically prepared. Four stay sutures were placed through the external anal sphincter before vertical transection (12 o'clock). Caudal retraction of the tear was performed using Allis tissue forceps (5 mares) or stay sutures before accurate apposition of the tear margins with steel staples below the tissue forceps. The mucosal edges were then sharply dissected leaving ∼5 mm edges which were apposed in a single layer (2-0 poliglecaprone 25) before stapler release. In 1 mare, the rectal tear was identified and apposed using a 2-layer hand-sutured closure. Systemic antibiotics and anti-inflammatory agents were administered postoperatively (5 mares) and standing abdominal lavage performed (3 mares).
Results— Four mares survived long term and subsequently became pregnant. Immediately after surgical repair, 1 mare was anesthetized for exploratory celiotomy and abdominal lavage but fractured her pelvis during recovery from anesthesia and was euthanatized. A 2nd mare was euthanatized after 72 h because of severe diffuse peritonitis; however, the repair was still intact.
Conclusion— In standing mares, rectal tears can be exteriorized by prolapse through the anal sphincter after sphincterotomy and repaired in 2 layers with staples oversewn with a continuous suture pattern.
Clinical Relevance— Rectal tears occurring as a result of parturition can potentially be repaired efficiently using an oversewn stapled primary closure technique.     

Ventrocaudal cystorrhaphy without urethral sphincterotomy in two broodmares

Two broodmares were diagnosed with rupture of the urinary bladder. One mare revealed abnormalities post partum and the other associated with ante partum uterine torsion. The clinical symptoms included mild abdominal pain, anorexia, decreased urinary volume and increased peritoneal fluid. In one mare, based on the creatinine level of the peritoneal fluid and serum biochemical abnormalities, uroperitoneum was diagnosed. In the other mare, the bladder rupture was found during the celiotomy for surgical repair of uterine torsion that was diagnosed upon rectal examination. Surgery was performed without a urethral sphincterotomy. The vaginal floor was incised in a standing position and the bladder was diverted into the vagina in order to suture the tears located in the ventrocaudal aspect of the bladder. Both mares survived after treatment for uraemia. Bladder rupture, although uncommon, may affect peripartum mares. Approach to the ruptured bladder without urethral sphincterotomy in a standing position should be considered as a choice for surgical repair.     

Evaluation of Postoperative Peritoneal Lavage in Standing Horses for Prevention of Experimentally Induced Abdominal Adhesions

Objective —To evaluate the postoperative use of peritoneal lavage for prevention of experimentally induced intraabdominal adhesions in horses.
Study Design —Areas of serosal abrasion were created on the jejunum of 12 horses. Postoperatively, six horses had peritoneal lavage, and six horses did not (controls). The number of adhesions was determined at necropsy 2 weeks after surgery.
Animals or Sample Population—12 horses.
Methods —Five sites of jejunal serosal abrasion were created in each horse. A 32 French thoracic catheter was placed into the right ventral aspect of the abdomen before closure of the abdominal incision. Treated horses had abdominal lavage with 10 L of lactated Ringer's solution on four occasions, then catheters were removed from all horses 34 hours after celiotomy. Horses were necropsied at 2 weeks to quantify the number of intraabdominal adhesions.
Results —All control horses and one treated horse developed intraabdominal adhesions. The number of adhesions was significantly less ( P <.0293) in treated horses. No adverse inflammatory reactions appeared to be associated with repeated peritoneal lavage using lactated Ringer's solution or use of an abdominal drain.
Conclusions —Peritoneal lavage reduced the frequency of intraabdominal adhesions.
Clinical Relevance —When postoperative adhesions are likely to develop, postoperative peritoneal lavage may decrease the frequency of adhesion formation.     

Gastrointestinal tract perforations caused by ingestion of multiple magnets in a dog

Objective – To describe a case of gastrointestinal tract perforation, septic peritonitis and coagulopathy caused by ingestion of multiple magnets in a dog. Case Summary – An 8‐month‐old castrated male Rottweiler, weighing 30.5 kg was presented for evaluation of vomiting and weakness. Abdominal radiography and abdominal ultrasonographic examination identified a metallic foreign object within the gastric lumen, presence of free peritoneal gas, and peritoneal effusion. Septic peritonitis was diagnosed by abdominal fluid analysis. Exploratory celiotomy revealed the presence of an omental abscess, and gastric and colonic perforations. Four magnetic foreign objects were found within the lumen of the perforated stomach. Surgical management including removal of the magnets, abscess debridement and excision, perforation repair, and abdominal drainage combined with intensive medical therapy resulted in complete recovery of this dog. New or Unique Information Provided – This report describes in detail the case management of a dog that developed both gastric and colonic perforations and severe morbidity secondary to ingesting multiple magnets.     

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

OBJECTIVE: To assess a laparoscopic technique for equine intestinal biopsy. STUDY DESIGN: Experimental study. ANIMALS: Seven adult horses. METHODS: Food but not water was withheld for 36 hours before laparoscopy. In 3 horses (group A) standing, right laparoscopic access to different small intestinal segments was compared with ventral median celiotomy access. Inaccessible segments were identified at necropsy. In 4 horses (group B), the feasibility of obtaining full-thickness duodenal and cecal biopsies and any associated morbidity were evaluated. Biopsy specimens were collected during standing right laparoscopy using a 2-step procedure and intracorporeal suturing technique, and abdominal lavage was performed. Horses were monitored clinically and by abdominal fluid cytology and microbial culture, and repeat laparoscopy was performed on day 6. RESULTS: Standing right flank laparoscopy provided good observation of small intestinal segments and enabled manipulation of all but 15-20 cm of the duodenum and approximately 40 cm more ileum compared with ventral median celiotomy. Group B horses had no complications, no adhesions, and no bacterial growth from peritoneal fluid samples. None of the horses had signs of abdominal pain. CONCLUSION: A 2-stage intestinal biopsy technique performed during standing, right flank laparoscopy may be a safe alternative to exploratory celiotomy and biopsy in normal horses. CLINICAL RELEVANCE: Right flank laparoscopy allows biopsy of intestinal segments including duodenum and 50% more of the ileum than is accessible by ventral median celiotomy. This technique should be evaluated in clinical patients.     

Repeated manual evacuation for treatment of rectal tears in four horses

Horses with tears that involve all layers of the rectum except the mesocolon (grade IIIb) have a poor prognosis for survival because of the difficulty in treating these wounds and the propensity for them to progress to full perforations (grade IV). Most treatments for grade-IIIb rectal tears involve surgery of some kind, but not all grade-IIIb rectal tears require surgical intervention. We report on 4 horses with grade-IIIb rectal tears that were evaluated via palpation per rectum and endoscopy. Two of 4 horses were admitted with signs consistent with shock and endotoxemia, and evaluation of all peritoneal fluid samples was indicative of nonseptic peritonitis. Horses were treated via administration of antibiotics and anti-inflammatory drugs and repeated manual evacuation of the terminal portion of the small colon and rectum. Treatment centered on preventing further enlargement of the rectal tear by eliminating the storage function of the terminal portion of the small colon and rectum. None of our horses had worsening of the original injury, and horses were discharged within 2 weeks of admission with full resolution of the rectal tear. Outcomes in the horses of our report indicate that repeated manual evacuation can be successful for treatment of horses with grade-IIIb rectal tears.     

Incarceration of Small Intestine Through Rents in the Gastrosplenic Ligament in the Horse

Incarceration of the small intestine through a rent in the gastrosplenic ligament was diagnosed in five horses. Three affected horses were mature males and two were mature females. Persistent moderate to severe abdominal pain, elevated heart rate, congested mucous membranes, serosanguineous peritoneal fluid, and distended small intestine on rectal examination were consistent findings.
Exploratory celiotomy or gross necropsy examination showed the incarcerated intestine to be distal jejunum or ileum. In all horses, the intestine had herniated cranially through the rent in the gastrosplenic ligament. The incarcerated intestine was situated lateral to the stomach and craniolateral to the spleen. Three horses underwent exploratory celiotomy, and the incarcerated small intestine was reduced by gentle traction and then resected. Two of these horses were alive more than 2 years postoperatively without recurrence of signs of abdominal pain, and one was euthanized because of dehiscence of the abdominal incision. Two horses were euthanized without surgical intervention, and necropsy examination revealed a recent rent in the gastrosplenic ligament. This condition should be considered in the differential diagnosis of causes of small intestinal strangulation and obstruction in the horse.     

The effects of heated and room-temperature abdominal lavage solutions on core body temperature in dogs undergoing celiotomy

To document the magnitude of temperature elevation obtained with heated lavage solutions during abdominal lavage, 18 dogs were lavaged with sterile isotonic saline intraoperatively (i.e., during a celiotomy). In nine dogs, room-temperature saline was used. In the remaining nine dogs, saline heated to 43+/-2 degrees C (110+/-4 degrees F) was used. Esophageal, rectal, and tympanic temperatures were recorded every 60 seconds for 15 minutes after initiation of the lavage. Temperature levels decreased in dogs lavaged with room-temperature saline. Temperature levels increased significantly in dogs lavaged with heated saline after 2 to 6 minutes of lavage, and temperatures continued to increase throughout the 15-minute lavage period.     

Plasma progesterone concentrations in pregnant and non-pregnant llamas (Lama glama)

Female llamas ovulate in response to copulation, and progesterone secretion by the corpus luteum indicates recent ovulation (mating) and, or, pregnancy. The plasma progesterone concentration was 0.9 to 1.4 ng/ml in five non-pregnant llamas and 7.4 to 9.2 ng/ml in three llamas in the last month of pregnancy. After ovulation had been induced in nine of 10 llamas by a single intramuscular injection of 500 or 750 iu of human chorionic gonadotrophin, the plasma progesterone concentration increased after two days from 0.5 to 1.2 ng/ml to 4.6 to 10.3 ng/ml after six to nine days and returned to basal values after 10 to 13 days, reflecting the life-span of a corpus luteum in the absence of conception. After a male llama had been introduced into a group of 13 females, 10 matings which resulted in eight conceptions occurred in the first 11 days, and 11 of the llamas became pregnant. The llamas' progesterone concentrations increased after mating and remained high if conception had occurred: 6 to 12 ng/ml in months one to four, and 5 to 9 ng/ml in months five to nine of the 11-month gestation. Two of the 13 llamas had high concentrations of progesterone although they did not become pregnant.     

THE MANAGEMENT OF RECTAL TEARS IN HORSES

Rectal trauma in horses is usually iatrogenic and carries a high mortality. Partial thickness tears heal without surgical assistance. Full thickness tears require surgical repair through the anus or a ventral laparotomy or, if these are not possible because of difficulty in gaining access to the tear in its usual site at the pelvic inlet, a diverting colostomy to allow the rectum to heal is necessary. This paper describes the management of 15 cases of rectal injury, only 3 of which survived. Two of these were partial thickness tears not treated surgically and the third had a temporary diverting colostomy.     

Fecal shedding of Giardia duodenalis, Cryptosporidium parvum, Salmonella organisms, and Escherichia coli O157:H7 from llamas in California

OBJECTIVE: To evaluate fecal shedding of Giardia duodenalis, Cryptosporidium parvum, Salmonella organisms, and Escherichia coli O157:H7 from llamas in California with respect to host factors and management practices. ANIMALS: 354 llamas from 33 facilities. PROCEDURE: Fecal specimens were collected and examined for G. duodenalis and C. parvum by means of immunofluorescent microscopy. Salmonella organisms were cultured by placing feces into selenite enrichment broth followed by selective media. Escherichia coli O157:H7 was cultured by use of modified tryptocase soy broth followed by sorbitol MacConkey agar, with suspect colonies confirmed by means of immunofluorescent microscopy. RESULTS: 12 of 354 fecal specimens (3.4%) had G. duodenalis cysts. Younger llamas (crias) were more likely to be shedding cysts, compared with older llamas. Farm-level factors that increased the risk of shedding were large numbers of yearlings on the property (> 10), smaller pen sizes, large numbers of crias born during the previous year (> 10), and large pen or pasture populations (> 20). None of the 354 fecal specimens had C. parvum oocysts. Seventy-six (from 7 facilities) and 192 (from 22 facilities) llamas were tested for Salmonella organisms and E. coli O157:H7, respectively. All fecal specimens had negative results for these bacteria. CONCLUSIONS AND CLINICAL RELEVANCE: Shedding of G. duodenalis was primarily limited to crias 1 to 4 months old. Llamas from properties with large numbers of crias born in the previous year, resulting in large numbers of yearlings in the current year, were at greater risk of infection. In addition, housing llamas in smaller pens or pastures and managing llamas and crias in large groups also increased the risk of G. duodenalis shedding.     

Detection of lysozyme in llama, sheep, and cattle tears

OBJECTIVE: To determine whether the tears of llamas, sheep, and cattle contain lysozyme and compare lysozyme concentrations in tears among these species. ANIMALS: 40 llamas, 5 sheep, and 36 cattle. PROCEDURE: Electrophoresis, western blot immunoassay for lysozyme, a spectrophotometric assay to detect tear lysozyme by its ability to lyse a suspension of Micrococcus lysodeiticus, and a microtiter plate colorometric assay were performed. RESULTS: A 13.6-kd protein band was detected by use of electrophoresis and western blot immunoassay in llama and sheep tears but not cattle tears. Results of spectrophotometric assay suggested that llama and sheep tears had high concentrations of lysozyme, whereas cattle tears had low concentrations. Results of the microtiter plate colorometric assay suggested that llama tears had high concentrations of lysozyme, whereas concentrations in sheep and cattle tears were lower. CONCLUSIONS AND CLINICAL RELEVANCE: Lysozyme concentrations in tears may vary among species and this variability may contribute to differing susceptibilities to ocular diseases such as infectious keratoconjunctivitis.     

Density of corneal endothelial cells, corneal thickness, and corneal diameters in normal eyes of llamas and alpacas

OBJECTIVE: To determine density of corneal endothelial cells, corneal thickness, and corneal diameters in normal eyes of llamas and alpacas. ANIMALS: 36 llamas and 20 alpacas. PROCEDURE: Both eyes were examined in each camelid. Noncontact specular microscopy was used to determine density of corneal endothelial cells. Corneal thickness was measured, using ultrasonographic pachymetry. Vertical and horizontal corneal diameters were measured, using Jameson calipers. RESULTS: Values did not differ significantly between the right and left eyes from the same camelid. There was no significant effect of sex on density of corneal endothelial cells or corneal thickness in either species. Mean density of endothelial cells was 2,669 cells/mm2 in llamas and 2,275 cells/mm2 in alpacas. Density of endothelial cells decreased with age in llamas. Polymegathism was observed frequently in both species. Mean corneal thickness was 608 microm for llamas and 595 microm for alpacas. Corneal thickness and density of endothelial cells were negatively correlated in llamas. Older (> 36 months old) llamas had significantly larger horizontal and vertical corneal diameters than younger llamas, and older alpacas had a significantly larger vertical corneal diameter than younger alpacas. CONCLUSIONS AND CLINICAL RELEVANCE: Density of corneal endothelial cells is only slightly lower in camelids than other domestic species. Density of endothelial cells decreases with age in llamas. Age or sex does not significantly affect corneal thickness in normal eyes of llamas and alpacas. Specular microscopy is useful for determining density of corneal endothelial cells in normal eyes of camelids.     

Open Peritoneal Drainage in Horses With Experimentally Induced Peritonitis

Peritonitis was induced in 12 horses by median celiotomy and 1 hour of small intestinal ischemia. Six horses had primary closure of the incision, whereas six horses had a plastic mesh sutured to the ventral abdominal wall leaving the abdomen open for ventral drainage. The mesh was removed after 5 days and the abdominal wall was closed by apposition of the linea alba and subcutaneous tissues and approximation of the skin edges. Peritoneal fluid was collected and analyzed for nucleated cell count and total protein concentration on days 0 and 5. Serum biochemical profiles, serum electrolyte concentrations, and complete blood counts were performed on days 0, 1, 2, 5, 6, 10, and 14. Body weight, rectal temperature, and physical examination findings were recorded daily for 30 days, then horses were euthanatized and the abdominal cavity was examined for the presence of adhesions. Histological examination was performed to assess the inflammatory response of the healing body wall; inflammation scores were significantly lower in horses that had primary closure of the incision. The mesh was well tolerated by all horses and allowed egress of peritoneal fluid for 5 days. Adhesions were present in four control horses and in two horses that had open peritoneal drainage. All horses that had open drainage developed incisional infections after mesh removal. Abdominal wall herniation did not occur in any of the horses. The mild peritonitis induced in this study was insufficient to establish the efficacy of open peritoneal drainage for an established peritonitis in horses; however, the results of this study indicate that open peritoneal drainage is feasible in horses.     

Colopexy as a Treatment for Rectal Prolapse in Dogs and Cats: A Retrospective Study of 14 Cases

Colopexy was evaluated as a treatment for recurrent rectal prolapse in eight dogs and six cats. Cases included in the study were from two institutions; the University of Pennsylvania School of Veterinary Medicine and the University of Tennessee College of Veterinary Medicine. Two different colopexy techniques were used: A simple suture technique was used in two cats and four dogs (University of Pennsylvania), and an incisional technique was used in four cats and four dogs (University of Tennessee). Rectal prolapse had not recurred in any of the 14 animals at the time of follow-up. Incisional dehiscence occurred in two animals and in one instance may have been related to the colopexy procedure. Infection at the colopexy site, secondary to suture penetration of the colonic lumen, is a potential complication of this procedure. Colopexy, using either surgical technique described here, was effective in preventing recurrent rectal prolapse.     

Laparoscopic surgical technique for repair of rectal and colonic tears in horses: an experimental study

OBJECTIVE: To determine the efficacy of laparoscopic surgical techniques for repair of rectal lacerations in horses. STUDY DESIGN: Experimental study. ANIMAL OR SAMPLE POPULATION: Thirty-two segments of equine bowel placed in an equine pelvitrainer, 8 equine cadavers, and 3 normal horses. METHODS: In experiment 1, 3 laparoscopic intestinal-repair techniques were evaluated in an equine pelvitrainer: suturing with needle holders, with an automatic suture device, and stapling with a hernia stapler. In experiment 2, descending colon lacerations were sutured laparoscopically using needle holders in a pelvitrainer and in equine cadavers. In experiment 3, iatrogenic rectal lacerations were sutured laparoscopically with needle holders in horses under general anesthesia. These horses were evaluated for 7 days' postoperatively by clinical examination and blood and peritoneal fluid analysis. The horses were euthanatized 7 days' postoperatively and necropsied. The repaired colonic segments were collected for determination of bursting pressures, degree of luminal narrowing, and microscopic examination of the suture line. RESULTS: For the 3 techniques, there was no significant difference in repair time or degree of luminal narrowing, but bursting pressure was higher in segments repaired by use of needle holders or with the suture device. Colonic and rectal lacerations were sutured successfully with laparoscopic needle holders. No major complications were recorded. At necropsy, adequate healing was confirmed by a high bursting strength (>140 mm Hg) and by histologic examination. CLINICAL RELEVANCE: A novel laparoscopic method can be used to repair iatrogenic rectal lacerations in horses. Whether this method may be used for clinical cases of rectal tears must be investigated.     

Non-surgical management of rectal tears in two mares

Two mares presented with life-threatening rectal tears were successfully treated with intensive medical management. Although surgery has been regarded as mandatory for grade 3 or 4 rectal tears in the past, recent reports have indicated the value of medical management alone. The case reports presented in this article detail the use of antibiotics, flunixin meglumine, laxative diets and faecal softeners in the medical management of two mares presented with grade 3 rectal tears.