Gastric Outflow Obstruction After Ingestion of Wood Glue in a Dog

Case Report

A 2-year-old, intact male, mixed-breed dog was presented to the emergency service at the University of Georgia Veterinary Teaching Hospital (UGAVTH) for a 12-day history of vomiting, lethargy, anorexia, and weight loss. The owners reported that 12 days prior to presentation, the dog had ingested approximately 2 ounces of an industrial-strength wood glue.^a The following day, the dog began vomiting 30 to 60 minutes after each meal. The dog did not vomit after ingesting small amounts of water. The owner reported that 10 days after ingesting the glue, the dog became markedly lethargic and was presented to the referring veterinarian. The dog had lost 4.5-kg body weight and had a painful, distended abdomen. A gastric foreign body was identified on abdominal radiographs, and the owners were referred to the UGAVTH immediately.

On presentation to the UGAVTH, the dog was lethargic but alert and responsive. The dog had a body condition score of 2 out of 5,¹ and he weighed 36 kg. The dog’s abdomen was distended, and a very large, firm mass was palpable in the cranial abdomen.

A lateral referral radiograph revealed a severely distended stomach with an organized, mottled soft-tissue and gas-opacity foreign body present within the lumen of the stomach [Figure 1]. The foreign body was surrounded by gas, which separated it from the gastric wall. The stomach displaced the small bowel and spleen caudally. Complete blood count (CBC) and serum biochemical analysis demonstrated an inflammatory leukogram with a left shift, consisting of 23.7 × 10³/μL segmented neutrophils (reference range, 2.9 to 12.0 × 10³/μL) and 1.3 × 10³/μL band neutrophils (reference range, 0.0 to 0.45 × 10³/μL). No significant abnormalities were noted on the serum biochemical profile.

A diagnosis of gastric foreign body with pyloric outflow obstruction was made, and the dog was prepared for exploratory celiotomy. The dog was preanesthetized with oxymorphone (0.08 mg/kg body weight, intravenously [IV]), diazepam (0.22 mg/kg body weight, IV), and atropine (0.02 mg/kg body weight, IV). Anesthesia was induced with propofol (4 mg/kg body weight, IV) and maintained with isoflurane. Cefazolin (22 mg/kg body weight, IV) was administered prior to surgery.

During exploratory celiotomy, a very large, distended stomach was identified. A circular perforation measuring approximately 1 cm in diameter was noted on the ventral surface of the body of the stomach. The stomach was isolated with saline-moistened laparotomy pads, and the ventral surface of the stomach was incised. A large (12 × 14 × 18 cm) foreign body was removed [Figures 2, 3] through the gastrotomy. The gastric mucosa appeared normal, and no other foreign material was found in the stomach. The gastrotomy site was then closed with a double-layer inverting suture pattern using 3-0 polydioxanone. The edges of the site of the perforation were resected, and the defect was closed with a simple-interrupted pattern using 3-0 polydioxanone. The rest of the abdomen was then explored, and mild petechiation, indicative of local peritonitis, was evident on the peritoneal surfaces. No other abnormalities were observed. The abdomen was lavaged extensively with warm saline and was closed routinely.

Postoperatively, the dog was treated with oxymorphone (0.08 mg/kg body weight, intramuscularly [IM], q 6 hours), cimetidine (10 mg/kg body weight, subcutaneously [SC], q 8 hours), metoclopramide (0.4 mg/kg body weight, SC, q 8 hours), and IV fluids (lactated Ringer’s solution, with 16 mEq/L KCl, at 4 mL/kg body weight per hour). Enrofloxacin (5 mg/kg body weight, IV, q 12 hours) and ampicillin (22 mg/kg body weight, IV, q 6 hours) were administered for therapy of the peritonitis secondary to the gastric perforation.

The dog recovered well, and oral enrofloxacin (5 mg/kg body weight, per os [PO], q 12 hours) was administered the following day. Cimetidine (10 mg/kg body weight, SC, q 8 hours) and metoclopramide (0.4 mg/kg body weight, SC, q 8 hours) were continued. Oral intake of food and water was instituted 12 hours after surgery. No vomiting was noted. Two days after surgery, a CBC and serum biochemical analysis revealed a mild inflammatory leukogram with 15.6 × 10³/μL segmented neutrophils and 0.6 × 10³/μL band neutrophils. The dog was discharged 2 days after surgery with instructions for the owner to continue enrofloxacin (5 mg/kg body weight, PO, q 12 hours) for the next 10 days. Communication with the owner 6 months after surgery confirmed no further problems.

Case Studies

A review of the ASPCA Animal Poison Control Center’s (APCC) computerized database from January 1998 to July 2001 revealed that gastrointestinal obstruction secondary to ingestion of this industrial wood glue has occurred in other dogs. Fourteen dogs were identified that had ingested the active ingredient, diphenylmethane diisocyanate (MDI). The records for each dog were reviewed to obtain the following information: signalment (i.e., breed, age, weight, sex), source of exposure, onset time of clinical signs (hours), most prominent clinical signs, timing of radiographs following exposure (hours), radiographic findings, treatment instituted, and final outcome. Follow-up calls were made to the animal owner or the veterinary facility to obtain information on progression of clinical signs and response to treatment [see Table].

The dogs ranged from 10 weeks to 3 years in age and from 1.5 to 57 kg in body weight. Eleven dogs were from a variety of pure breeds, and three dogs were of mixed breed. Exposure occurred in 10 of the 14 dogs when containers of adhesive were chewed open or knocked over, leading to ingestion of at least part of the contents. Other sources of exposure included recently spilled glue, a paper towel with glue on it, and a craft stick with glue on it.

Thirteen of the 14 dogs were reported to exhibit one or more clinical signs that developed from 15 minutes to 20 hours after exposure. The majority (11/13) of dogs showed clinical signs within 12 hours of contact with the wood glue. Vomiting (9/13), anorexia (8/13), and lethargy (7/13) were the most commonly reported signs. Hematemesis was reported in one of the nine dogs that developed vomiting. Visible abdominal distention and/or a large, firm stomach upon palpation (n=4), diarrhea (n=3), tachypnea (n=2), and dehydration (n=2) were reported less frequently.

Abdominal radiographic findings were described in seven of the eight dogs that required surgery. Reports of the radiographic findings taken 4 hours to 5 days following exposure included a large, radiopaque, mottled density in the stomach, gastric dilatation, or both.

Eight of the 13 dogs affected had persistent clinical signs that necessitated surgical removal of the adhesive. In these dogs, the adhesive expanded to form a large foreign body that, in some cases, extended into the pylorus or filled the entire stomach. There were no reports of obstruction distal to the pylorus. The mass of adhesive was usually firm enough to retain its shape, yet soft enough to easily fragment, facilitating removal from the stomach. Two dogs had evidence of mild to moderate mucosal irritation at the time of foreign body removal. All eight dogs were exposed to the product container, and all recovered well following surgery. Adjunctive medication administered to these dogs varied, but generally included broad-spectrum antibiotics, sucralfate, and H₂-receptor antagonists.

In five dogs, clinical signs resolved 3 to 9 days after exposure, without surgical intervention. Only two of these five dogs were exposed to the product container. Treatment for three of the five dogs included antibiotics and dietary changes. Clinical signs resolved in the other two dogs without treatment.

Discussion

Diphenylmethane diisocyanate is the active ingredient in the industrial-strength wood glue in this report. Isocyanates and polyisocyanate prepolymers are used to prepare urethanes and polyurethanes. Commonly used diisocyanates are toluene diisocyanate (TDI), MDI, and hexamethylene diisocyanate (HDI). When used, these compounds go through an exothermic polymerization reaction that helps to cure and set the end product. During this exothermic reaction, some diisocyanate may volatilize and escape into the environment.² However, after proper curing, the foams and polyurethanes that have been produced contain no free diisocyanate compounds.

Reports of diisocyanate toxicity in humans and animals involve respiratory (i.e., inhalant) and dermal exposures following contact with the chemical in a liquid or aerosolized form.^2–11 Isocyanates irritate the skin, lungs, conjunctiva, and the gastrointestinal tract in humans and animals. The respiratory system is the organ most susceptible to toxicity. Euphoria, ataxia, mental aberrations, sensitization (primarily respiratory), bronchitis, emphysema, and cor pulmonale have been reported in humans.¹² Gastrointestinal symptoms including vomiting and abdominal pains have followed inhalation of vapor or aerosol in humans. However, epigastric and substernal pain may be secondary to the paroxysmal or persistent cough associated with inhalation.¹²

Treatment recommendations after oral exposure to diisocyanates in humans include immediate dilution with milk or water, administration of activated charcoal, and monitoring the patient for respiratory distress or allergic reactions.¹² Due to the irritant nature of isocyanates, emesis is not advised. These recommendations reflect the goals of minimizing systemic effects and local irritation. It is not known if these recommendations have any impact on the progression of the isocyanate from a liquid to a solid phase or on the final volume of the solid phase.

This series of cases is, to the authors’ knowledge, the first report of gastrointestinal obstruction following ingestion of MDI in dogs or any other species. Although the majority of the described cases developed gastric outflow obstruction that required surgical intervention, there were few systemic side effects, and all dogs recovered without complication. All nine dogs that required surgery were exposed to the product containers. Radiographic changes consistent with gastric outflow obstruction were usually evident within 24 hours after exposure.

Conclusion

Diphenylmethane diisocyanate products present a unique hazard to companion animals because of their propensity for volume expansion following ingestion. Veterinarians must be aware of the potential for ingestion of even a small amount of liquid MDI to develop into a large physical obstruction within the gastrointestinal tract when the substance progresses into the solid phase. Dogs for which ingestion of a MDI product is suspected should be closely monitored. If vomiting is severe or persists for >24 hours, abdominal imaging studies are recommended to rule out obstructive disease. If obstruction is not detected, supportive care consisting of nothing PO, gastric protectants, antiemetics, and IV fluid theraphy should be instituted for 24 to 72 hours. If pyloric obstruction or a gastric mass is detected, celiotomy with gastrotomy and surgical removal of the mass are recommended. Based on this series of dogs with MDI ingestion, prognosis for full recovery is excellent with appropriate medical or surgical management or both.