Lethal acute hemorrhage from an aortoesophageal fistula following endoscopy-assisted esophageal foreign body removal in a dog.

OBJECTIVE: To describe the clinical presentation of a dog with fatal hemorrhage from an aortoesophageal fistula (AEF) immediately following endoscopic removal of an osseous esophageal foreign body. CASE SUMMARY: A 12-year-old, male mixed-breed dog presented to a university hospital with a 6-day history of gagging, hematemesis, and anorexia. Physical examination upon arrival was unremarkable. Blood work revealed leukocytosis without anemia. Thoracic radiographs from the referring veterinarian demonstrated the presence of an osseous esophageal foreign body at the level of the heart base. Subsequently, esophagoscopy was performed under general anesthesia. A triangular-shaped, osseous esophageal foreign body was visualized at the level of the heart base and successfully removed. Following its removal, a deep, nonbleeding, presumably nonperforated, esophageal ulcer was revealed. While recovering from anesthesia, the dog's condition acutely deteriorated, with absence of spontaneous respiration, severe tachycardia, hypotension, white-pale mucous membranes, and hypothermia. Severe anemia was present, with hypovolemic shock likely secondary to acute, postprocedural bleeding. Medical management included rapid packed red blood cell transfusion, crystalloid fluid therapy, and tranexamic acid. Despite initial stabilization, several hours later, the dog suffered cardiac arrest and cardiopulmonary resuscitation (CPR) was unsuccessful. At postmortem examination, a 1-mm AEF was identified on the ventral aspect of the aorta that communicated with the overlying esophagus. NEW OR UNIQUE INFORMATION PROVIDED: Aortoesophageal fistulas should be considered in any patient with severe bleeding following esophagoscopy. A history of hematemesis in a dog with an esophageal foreign body should raise suspicion of an AEF and dictate case management accordingly.

Technical Note: Collection and preparation techniques change nutrient composition of masticate collected from esophageally fistulated cattle.

Two experiments determined effects of collection and preparation techniques on nutrient composition of masticate samples from esophageally fistulated cattle. In Exp. 1, 12 esophageally fistulated cattle were maintained on 2 precollection diets, high CP (24% CP; = 6) or low CP (7.7% CP; = 6), for 8 d. On d 9, the esophageal plug was removed, screen bottom bags were attached, and each cow was offered fresh grass. Immediately after fresh grass sample collection was complete, dry grass (hay) was offered and a sample was collected. Blood samples were collected and analyzed for serum urea nitrogen concentration. Masticate samples of both fresh and dry grass were divided and each was either squeezed by hand until no more saliva could be removed or remained unsqueezed. In Exp. 2, 10 esophageally fistulated cattle were fitted with either screen ( = 5) or solid ( = 5) bottom collection bags after removal of the esophageal plug and presented grass hay, fresh grass, alfalfa hay, or fresh alfalfa. In Exp. 1, the precollection diet did not affect ( = 0.49) CP content of masticate even though serum urea nitrogen tended to be greater ( = 0.08) for high- vs. low-CP precollection diets. Forage harvest type offered (fresh vs. hay) interacted ( = 0.01) with preparation technique (squeezed vs. unsqueezed) for CP, where CP decreased in squeezed fresh samples ( < 0.001) but not in squeezed grass hay samples ( = 0.98). In Exp. 2, ingestion greatly increased levels of ash ( < 0.001). Crude protein was greater ( < 0.004) before ingestion for all samples except grass hay ( = 0.43). Levels of NDF were similar before and after ingestion ( > 0.15) for all samples except fresh alfalfa, which was greater after ingestion ( = 0.002). Ingestion status did not affect in vitro OM disappearance (IVOMD; > 0.34) except for grass hay, which was greater after ingestion ( < 0.001). Bag type (screen vs. solid) did not affect ash and NDF ( > 0.31), except for fresh alfalfa, which were greater ( < 0.03) for solid bottom bags. Bag type did not affect alfalfa CP ( = 0.71) but did affect grass CP, which was lower ( = 0.02) for solid bottom bags. Bag type did not affect IVOMD ( > 0.33). More ( = 0.01) fresh forage than hay was recovered through the esophageal opening. Previous diet did not impact masticate samples but squeezing impacted CP levels of high-quality forage and therefore should not be performed. Nutrient values should be reported on an OM basis.

Fatal aortic oesophageal fistula following oesophageal foreign body removal in a dog.

An eight-month-old male Pomeranian was presented with hypovolaemic shock 7 days after successful oesophageal foreign body removal. On presentation the dog was anaemic and no coagulation abnormalities were detected. A fluid-filled oesophagus was visible on thoracic radiography and frank blood was aspirated from the oesophagus following oro-oesophageal intubation. Fluid resuscitation and blood transfusions were administered but attempts at stabilisation were unsuccessful and the dog died. At post-mortem examination, a 2-mm aortic oesophageal fistula was identified on the ventral aspect of the aorta at the level of heart base that communicated with the overlying oesophagus. Aortic oesophageal fistula has been reported in human medicine and occurs secondary to a number of conditions including oesophageal foreign bodies. These prove fatal without rapid stabilisation and surgery.

Canine bronchoesophageal fistulas: case report and literature review.

A bronchoesophageal fistula (BEF) is defined as a communication between the esophagus and one or more bronchi. BEFs are commonly associated with esophageal diverticula, which are circumscribed outpouchings of the esophageal wall. This article presents the report of a case seen at Louisiana State University Veterinary Teaching Hospital and Clinics in 2006 and reviews the pathogenesis, diagnosis, and treatment of esophageal diverticula and BEFs. The BEF in the case presented was of a very rare form, involving only the accessory lung lobe bronchus.

Urea metabolism in beef steers grazing Bermudagrass, Caucasian bluestem, or gamagrass pastures varying in plant morphology, protein content, and protein composition.

Pastures of Bermudagrass (Cynodon dactylon, BG), Caucasian bluestem (Bothriochloa caucasica, CBS), and gamagrass (Tripsacum dactyloides, GG) were evaluated from the perspectives of forage composition, selection during grazing, and N metabolism in beef steers. All pastures were fertilized with 78 kg/ha of N approximately 60 and 30 d before sample collection. In 2000 and 2001, 12 steers (250 kg of BW) were blocked based on BW and then assigned randomly to a replicated, randomized complete block design, with 2 pastures of each forage and 2 steers per pasture. Three other steers with esophageal fistulas were used to collect masticate samples to represent intake preferences. Herbage mass was >1,900 kg/ha. After at least 14 d of adaptation, urine and blood samples were collected for determination of serum urea N and percentage of urinary N in the form of urea. One steer per pasture (6 steers per year) was infused i.v. with (15,15)N urea for 50 h before collecting urine for 6 h to measure urea N enrichment, urea entry rate, urinary urea excretion, gut urea recycling, and return of urea N to the ornithine cycle. The canopy leaf:stem DM ratio differed (P = 0.01) among BG (0.50), CBS (1.01), and GG (4.00). Caucasian bluestem had less CP (% of DM) than GG or BG in the canopy (9.6 vs. 12.0 or 12.3, P = 0.07) and in the masticate (9.8 vs. 14.7 or 13.9, P = 0.04). Bermudagrass had less true protein (% of CP) than CBS or GG in the canopy (72.9 vs. 83.3 or 83.0, P = 0.07) and in the masticate (73.7 vs. 85.8 or 88.0, P = 0.04). Compared with GG and BG, CBS had less serum urea N (10.1 or 12.2 vs. 2.5 mM, P = 0.01), urea entry rate (353 or 391 vs. 209 mmol of N/h, P = 0.07), and urinary urea excretion (105 or 95 vs. 18 mmol of N/h, P = 0.04), and a greater return of urea N to the ornithine cycle as a proportion of gut urea recycling (0.109 or 0.118 vs. 0.231, P = 0.02). Urea production and recycling in these steers responded more to the N concentration in the grasses than to differences in plant protein fractions. There was no evidence of improved N capture by the steers due to changes in the leaf:stem ratio among the grasses at the herbage mass evaluated.

Fluoroscopic and endoscopic localization of an esophagobronchial fistula in a dog.

A 10-month-old, intact male Chihuahua presented for a 7-month history of regurgitation and coughing. Survey radiographs revealed a soft-tissue opacity within the distal esophagus. A contrast study confirmed the presence of an esophagobronchial fistula. Endoscopic removal of foreign material within the esophagus allowed for visualization of an esophageal diverticulum. Bronchoscopic examination revealed the presence of an abnormal opening in a right caudal tertiary bronchus. Passage of a cardiac guidewire was accomplished, confirming the presence of the fistula and aiding its subsequent surgical removal.

Surgical treatment of a congenital bronchoesophageal fistula in a dog.

A 1-year-old male Cairn Terrier was evaluated for chronic coughing that was aggravated by eating or drinking. Radiography revealed an esophageal diverticulum, regional megaesophagus, and focal interstitial densities in the right caudal and middle lung lobes. Using fluoroscopy and contrast radiography, contrast material was seen to accumulate in the diverticulum and to reflux into the right middle, caudal, and accessory bronchi. Radiographic diagnosis was bronchoesophageal fistula. Via right eighth intercostal space thoracotomy, the abnormal connection between esophagus and caudal lobe of the right lung was identified, the lobe was resected, and the esophagus was closed. Histologic examination of the connecting tissue revealed a lining of stratified epithelium, with the superficial layer being predominantly ciliated columnar epithelium. Several findings led to the conclusion that the fistula was a congenital lesion, arising from aberrant formation of the respiratory tract from the embryologic digestive tract. Histologic examination revealed smooth muscle and lack of inflammation in tissue surrounding the fistula, which are criteria for identifying congenital bronchoesophageal fistula in human patients. The dog was young and did not have a history of esophageal foreign bodies. Postoperative complications were not encountered, and 9 months later, the dog was reported to be eating dry dog food without coughing. Congenital and acquired bronchoesophageal fistulas in dogs are reported infrequently. Furthermore, 2 of 12 previously reported bronchoesophageal fistulas in dogs, one of which was considered congenital, developed in Cairn Terriers.

[Bilateral pleuritis following esophageal fistula in a horse as a complication of a Gasterophilus infection]. / Beiderzijdse pleuritis na een oesofagusfistel bij het paard als complicatie van een Gasterophilus-infectie.

A six-year-old pregnant Haflinger mare of 510 kilograms died from bilateral pleurisy following a hospitalisation period of ten days, during which she was treated with various antibiotics. At necropsy a bilateral fibrinopurulent pleurisy accompanied by an ulceration of the cardia of the stomach measuring once cm2 was found. In the wall of the oesophagus, close to the cardia, there was a fistula harbouring a 3rd stage Gasterophilus larva. The epithelial layer at this site was unimpaired and no gross connection between the fistula and the ulceration of the cardia was observed. The fistula was in communication with both pleural cavities. Microscopic examination showed an inflammatory infiltration as a connection between the fistula in between the oesophageal muscular layers and the bottom of the cardiac ulcer. The Gasterophilus larva as the possible cause of the bilateral pleurisy is discussed.

Problems and complications associated with esophageal surgery.

Complications associated with esophageal surgery can be overcome by careful surgical technique, patience, and the selection of appropriate treatments for esophageal lesions. Two retrospective studies that evaluated the results of esophageal surgery in dogs and cats reported successful outcomes in 77% and 85% of the cases. By following classic surgical tenets, the use of fine non-reactive suture material, the precise apposition of tissues, and the avoidance of tension on the suture line, the esophagus will heal admirably.

Surgical repair of an esophageal stricture in a horse.

An esophageal stricture was diagnosed in a 9-month-old quarterhorse by esophagoscopy and positive pressure contrast esophagography. Medical management and two attempts at surgical intervention were unsuccessful. The initial surgical technique used was a linear esophagotomy, mucosal resection and anastomosis, and closure of the muscular tunic, which resulted in a more severe stricture. The second surgical procedure was interruption of the stricture cicatrix by a single linear esophagotomy and primary closure of only the esophageal muscular tunic. This technique resulted in an increased lumen diameter, but failed to adequately resolve the stricture. Successful resolution of the stricture with return to a normal diet was achieved by a two stage repair using formation of an esophagostomy to stabilize the esophagus, followed by fenestration of the mucosal-submucosal cicatrix. Six months postoperatively, the horse was asymptomatic on a normal diet.

Surgical diseases of the esophagus.

The diagnosis and management of surgical diseases of the esophagus are discussed. Esophageal foreign bodies, strictures, esophagobronchial fistulas, diverticula, gastroesophageal intussusception, hiatal hernias, and megaesophagus are included in the discussion.

Bronchoesophageal fistula and transient megaesophagus in a dog.

Bronchoesophageal fistula and megaesophagus were diagnosed in a dog. Within 2 days after surgical correction of the bronchoesophageal fistula, peristalsis in the thoracic portion of the esophagus returned to normal and the esophagus resumed its normal size. The cause of the fistula was attributed to damage from a foreign body. The cause of the transient megaesophagus likely was related to the bronchoesophageal fistula.

Esophageal patch grafting as a treatment for esophageal stricture in a horse.

Esophageal patch grafting, using the sternocephalicus muscle, was used for treatment of cervical esophageal stricture in a mare. The mare was maintained during the initial healing phase by total parenteral nutrition.