Endoscopic Removal of Gastric Foreign Bodies with a Bottle Liner in 12 Dogs (2020–2023)
ABSTRACT
Endoscopy is widely used to remove gastric foreign bodies using grasping forceps and loop snares to manipulate and retrieve the foreign material. However, as not all foreign bodies can be removed using conventional endoscopic techniques, this case series describes the use of bottle liners for the removal of gastric foreign bodies in 12 dogs between 2020 and 2023. A 4 oz bottle liner (Drop-Ins) was placed at the end of the endoscope and pushed into the stomach. With the help of forceps introduced into the operating channel, the foreign body was pushed into the bottle liner. The bottle liner containing the foreign body was then extracted with the help of traction threads. The technique was used as the initial retrieval method in 5 dogs because of smooth (i.e., difficult to grasp) or sharp (i.e., that may damage the digestive tract mucosa during removal) foreign bodies and as a rescue procedure in 7 dogs. Foreign body retrieval was successful in all 12 dogs, with minor complications reported in 5 dogs (erosions and bleeding of the gastroesophageal sphincter). The use of a bottle liner represents an affordable alternative to gastrotomy when foreign bodies cannot be grasped with forceps or snares.
Introduction
Gastric foreign bodies are relatively common in dogs. They can be removed by induction of emesis, endoscopy, or surgery. Vomiting can be induced with apomorphine, which is a dopaminergic agonist, or tranexamic acid, which is a molecule used as an antifibrinolytic with emetogenic properties.1–3 Apomorphine and tranexamic acid induce expulsion of gastric foreign bodies with a success rate up to 75%1,3 and 96%,2 respectively. However, induction of emesis is contraindicated with sharp foreign bodies or in patients with dull mentation, as this increases the risk for aspiration. Furthermore, the success rate is lower in older animals, in animals premedicated with drugs such as opioids or antiemetics, or when the foreign body has been present for more than 24 hr.1 In these cases, endoscopy is the alternative treatment of choice, with up to 97% success rate.4 Depending on the type of foreign body, the most commonly used instruments include grasping forceps, Roth net, wire basket, and loop snare, all of which are introduced into the operating channel.5 However, removal of the foreign body may fail when its surface is smooth or its size is too large. As with emesis induction, these techniques should be used cautiously with sharp foreign bodies.
A bottle liner technique may be an alternative option in these situations. The bottle liner is a plastic bag developed for baby bottles to limit air intake during feeding. In an online survey of internists (DACVIM) and criticalists (DACVECC), 56% of respondents had used the bottle liner technique to remove gastric foreign bodies. The success rate with this technique was estimated to be between 51 and 90% by 36% of the panel and between 90 and 100% by 24% of the panel.5 The bottle liner technique was most often used for rounded or sharp foreign bodies. Although its use is mentioned in one study5 and in one poster,6 the bottle liner technique has not been well described in the veterinary literature. Therefore, the aims of the current study were (1) to describe the bottle liner technique for gastric foreign object removal in dogs and (2) to report its indications, use, and outcome in a referral veterinary hospital.
Materials and Methods
Study Design and Inclusion Criteria
This was a retrospective case series. Case logs maintained by boarded internists and internal medicine residents at Frégis referral veterinary hospital from January 2020 to April 2023 were reviewed to identify dogs that had endoscopic foreign body retrieval using the bottle liner technique. The search term used was “bottle liner.” The medical record of included dogs was examined, and data collected included signalment, history (especially duration of clinical signs), type of foreign bodies removed, ultrasonographic or radiographic findings when available, endoscopic findings, the foreign body retrieval techniques used, outcomes, complications, and duration of the procedure when available. A diplomate of the European College of Veterinary Diagnostic Imaging reviewed all available radiographic and ultrasound images. Informed consent for the foreign body removal procedure under anesthesia was obtained from the pet owners at admission. All dogs were clinically managed according to contemporary standards of care.
As the time required to remove the foreign body was not typically captured in the medical record except for the latest dogs included in the study, this was estimated by comparing the timing of photographs taken at the start of the procedure and after foreign body retrieval. The timing could not be estimated if no images were taken after foreign body removal.
Endoscopic Procedure
Different premedications (i.e., midazolama [0.2 mg/kg, IV] and dexmedetomidineb [1 to 3 µg/kg, IV]) were used depending on the dogs’ clinical status. Anesthesia was induced with propofolc used to effect and maintained with isofluraned in oxygen via an endotracheal tube. Analgesia was provided with buprenorphinee (20 to 30 µg/kg, IV). Dogs were positioned in the left recumbency. The mouth was held open with a mouth gag or a plastic cylinder, allowing the endoscope to be introduced into the digestive tract safely.
Two flexible endoscopesf,g were used during the study period.
During the procedure, three operators were always present: one manipulated the endoscope, one held the threads attached to the bottle liner, and the last operator monitored anesthesia.
Description of the Bottle Liner Technique
Preparation of the Device
A 4 oz (118 mL) Drop-Ins bottle liner was used. Three threads of nonabsorbable 2-0 pseudomonofilament polyamideh were placed in three different locations at the opening of the bottle liner. Each suture was introduced using a 30-gauge needle and fixed with at least four single knots (Figure 1). The length of the threads was adapted to the length of the dog so that the threads were longer than the distance between the nasal planum and the mid-abdomen. The endoscope was advanced into the bottle liner, and the outer surface of the liner was lubricated. An assistant held the free ends of the sutures (if there were only two operators, hemostats could also be used to secure the suture ends) to prevent inadvertent loss into the esophagus.
Citation: Journal of the American Animal Hospital Association 60, 2; 10.5326/JAAHA-MS-7394
Gastric Foreign Body Removal Procedure
The technique was similar for all dogs and is illustrated in Figure 2 and Supplementary Video I. The bottle liner was placed over the distal end of the endoscope; next, both were introduced into the mouth and advanced into the stomach. The bottle liner was transparent, making it easy to maneuver the gastroscope through the gastrointestinal tract. Once in the stomach, the bottle liner was pushed into the pyloric antrum. The endoscope was then pulled back to visualize both the bottle liner opening and the foreign body. A forceps was introduced into the operating channel of the endoscope to mobilize the foreign body by grasping it or pushing it into the bottle liner. Once the foreign body was inside the bottle liner, the threads were gently pulled to extract the bottle liner containing the foreign body out of the gastrointestinal tract. The endoscope and the bottle liner were removed simultaneously to insufflate the gastrointestinal tract while the bottle liner was removed and to witness the foreign body extraction.
Citation: Journal of the American Animal Hospital Association 60, 2; 10.5326/JAAHA-MS-7394
The technique was repeated in dogs with multiple foreign bodies until all the material was removed.
Statistical Analysis
Only descriptive statistics were used owing to the small sample size of the case series. Numerical data were expressed as median and range.
Results
Animals
Twelve dogs were included during the study period; six were males (four neutered) and six were females (four neutered). The median age was 6 yr, ranging from 1 yr to 14 yr. The median body weight was 12 kg, ranging from 2.5 kg to 43 kg. Represented breeds included two of each of the following: German shepherd, Staffordshire bull terrier, and mixed-breed dog, and one of each of the following: English cocker spaniel, French bulldog, Jack Russell terrier, Yorkshire terrier, Chihuahua, and bearded collie.
History and Clinical Signs
Seven dogs were presented because of clinical signs related to foreign body ingestion. Two dogs had incidental diagnoses, one dog was asymptomatic but was observed ingesting the object 5 days before presentation, and the remaining two dogs had incomplete records with no information about the nature and duration of clinical signs.
Of the seven dogs that presented for clinical signs, the duration of clinical signs ranged from 1 to 14 days, with a median of 2 days. Five dogs were vomiting, and one had diarrhea and abdominal pain. One dog was presented for abdominal distension, ptyalism, coughing, and gagging secondary to esophageal and gastric foreign bodies. One dog was presented for clinical signs related to hemolytic anemia suspected secondary to a metallic gastric foreign body. The diagnosis of gastric or esophageal foreign body was made by abdominal ultrasound in three dogs, radiography in three dogs, and endoscopy in one dog. In the latter case, the radiologist described an empty gastric lumen with thickening of the gastric wall and regional lymphadenopathy. These suggested the presence of ulcers, which prompted endoscopic evaluation.
Two dogs had incidentally diagnosed foreign bodies; in one dog, these were identified during the diagnostic work-up of hepatic masses and hemoabdomen, and in the other dog, after being hit by a car.
Type and Localization of Foreign Bodies
The type and localization of foreign bodies are summarized in Table 1. Nine dogs had a single gastric or esophageal foreign body, and three dogs had two or more. Foreign bodies included dog toysi (n = 2), pieces of plastic or rubber (n = 2), stones (n = 2), and one of each of the following: ball, pipe connector, pieces of plastic balls, and a beer cap. One dog had both esophageal and gastric foreign bodies, which were yak cheese treats. One dog had an esophageal foreign body (presumptive phytobezoar) that was pushed into the stomach before removal. One dog also had a nonobstructive jejunal foreign body, which was not treated because the owners declined further care. Some of these foreign bodies are shown in Figure 3.
Citation: Journal of the American Animal Hospital Association 60, 2; 10.5326/JAAHA-MS-7394
Endoscopic Removal
The techniques used to remove the foreign bodies are summarized in Table 1. For seven dogs, the bottle liner was used as a secondary method. Removal was first attempted with endoscopic forceps or snare. These dogs had ingested the following foreign bodies: dog toyi (n = 2), pieces of plastic or rubber (n = 2), yak cheese treats, stone, and the presumptive phytobezoar.
For four dogs, the bottle liner was used as the initial method because the surfaces of the foreign bodies prevented them from being grasped with a forceps or a snare (i.e., the ball, the stone, and the pipe connector) or because their surface could damage the mucosa (the beer cap).
For the last dog, the forceps and the bottle liner were used based on the size and sharpness of the foreign material (the fragments of plastic ball).
The duration of the procedure, estimated or measured, is indicated in Table 1. It was estimated between 3 and 5 min in four dogs (i.e., removal of the beer cap, the ball, the presumptive phytobezoar, and a stone), 8 min for removal of yak cheese treats, 18 min for removal of a stone, and 40 min for removal of a rubber piece. For the dog that ingested the hardened pieces of plastic balls, the extraction procedure was not timed but took longer than 1.5 hr.
Complications
Five dogs showed signs of esophageal and cardial mucosal erosions associated with bleeding after foreign body removal (Table 1).
For the two smallest dogs in our study (i.e., a 2.5 kg Chihuahua and a 3 kg Yorkshire terrier), manipulating the bottle liner inside the stomach was deemed more difficult because the liner occupied almost all the gastric volume. For the Yorkshire terrier, traction was achieved with the threads and with the forceps within the operating channel of the endoscope and used to grasp the bottle liner.
Outcome
Treatments administered after the procedure are listed in Table 1. All dogs except two were discharged on the same day. The dog with hemoabdomen was discharged the day after the procedure; that dog did not show clinical signs related to hemoabdomen, and the presence of metastases contraindicated surgical management of the liver masses. The dog that presented with hemolytic anemia secondary to a pipe connector suffered cardiorespiratory arrest that did not respond to resuscitation attempts the night after foreign body removal. Thoracic and abdominal radiographs revealed no evidence of gastric or esophageal perforation. The dog was not autopsied, but thromboembolism was suspected.
The dog that ingested pieces of yak cheese re-presented to the emergency department 10 days after foreign body removal for abdominal discomfort and distension despite sucralfatej (1 g, 1.5 sachet per os [PO], q 12 hr, 7 days) and maropitantk (2 mg/kg PO, q 24 hr, 4 days). Thoracic and abdominal radiographs did not identify any persistent foreign bodies or signs of gastrointestinal obstruction. Metoclopramidel (0.2 mg/kg PO, q 8 hr, 15 days) and omeprazolem (1.08 mg/kg PO, q 12 hr, 15 days) were added to the treatment.
All dogs were then lost to follow-up, including the patient with the nonobstructive jejunal foreign body.
Discussion
This study describes the use of a bottle liner for endoscopic removal of gastric foreign bodies. Although the technique is already used by some specialists,5,6 to the authors’ knowledge, this manuscript is the first to describe the procedure and its use in clinical practice.
The bottle liner was used for several reasons. In more than half of the cases, it was used as a second-line procedure when a forceps and/or a snare failed to remove the foreign body (per the clinician procedure report). In the remaining cases, it was used as a first-line procedure. Although the decision to use the bottle liner as the initial method of retrieval was at the clinician’s discretion, this decision was likely made to avoid gastric and esophageal mucosal damage by sharp foreign bodies or because the foreign bodies were assumed to be difficult to grasp because of their smooth surface.
The success rate in foreign body removal was 100% in this study, which is better than the previous description of this technique,5 in which 36% of survey respondents reported a success rate of 51–90% and 24% reported a success rate of 90–100%. However, that success rate was an estimate based on a questionnaire response; recall bias was possible and likely misestimated the actual success rate. Given the retrospective nature of our study, omission of cases in which the bottle liner was used but was not reported in the procedure report is possible but considered unlikely, as all the techniques attempted to remove the foreign body should be listed in the procedure report. However, because of the slight risk of case omission, the success rate may have been overestimated.
According to previous studies, the success rate of gastroscopy for foreign body retrieval varies between 64 and 100%.4,7–9 Only one study detailed the types of foreign bodies involved in removal failure: a rubber ball, mango pits, and a piece of plastic.9 Although the cause of the failure to remove them was not reported explicitly, we can suspect that this was related to the difficulty of grasping their surface, at least for the rubber ball and the mango pits. The authors did not report the use of a bottle liner in their study. Similar foreign bodies were extracted using the bottle liner technique in our study. Consequently, we strongly recommend trying the bottle liner technique for difficult-to-remove gastric foreign bodies before considering surgery. Although the success rate of gastrotomy is high (i.e., between 94 and 100%),7,10 endoscopic removal reduces the hospitalization time,7 likely decreases complication risks and cost of management, and avoids postoperative constraints.
Dogs that have ingested balls, rocks, or metal are less likely to vomit when apomorphine-induced emesis is attempted.1 These types of foreign bodies are also often difficult to grasp with forceps or snares during endoscopy. Therefore, the bottle liner technique could be used as a primary approach to limit anesthesia duration and delay in foreign body removal.
Significant complications such as gastric perforation can arise from endoscopic gastric foreign body removal.4 No gastric perforation occurred in our study following the bottle liner technique. One dog died the night after the endoscopy, but radiographs did not identify any evidence of gastric or esophageal perforation. Some minor complications were, however, reported with the bottle liner technique in our study, especially erosions and bleeding at the gastroesophageal sphincter in four dogs. Notably, these complications are prevalent in all endoscopic procedures, and further studies are needed to determine whether the occurrence of these minor complications is reduced with the bottle liner technique compared with the use of other techniques.
In our case series, one dog had esophageal and gastric yak cheese treats, and one dog had an esophageal presumptive phytobezoar. In both cases, the usefulness of removing the foreign body after pushing it into the stomach could be questioned. Bones or dental treats are usually left in place in the stomach and digested without complication.11,12 In a previous study, pyloric or small intestinal obstructions were not reported in any of the 16 dogs where a dental chew treat stuck in the esophagus was pushed into the stomach by endoscopy.12 In our study, they were removed because of their large size and because the composition of the foreign body was uncertain before its removal.
We identified limitations in using the bottle liner technique related to the size of the dog and the number of foreign bodies to remove. For the smallest dogs in our study, manipulating the bottle liner inside the stomach was difficult because it occupied almost all the gastric volume. A smaller bottle liner would have been useful but was not available at the time of manuscript preparation. One dog ingested multiple pieces of plastic, and although that procedure was not timed, the duration was estimated to be longer than 1.5 hr. In this case, a gastrotomy likely would have reduced the anesthesia time. However, it was decided to proceed with the bottle liner technique because this dog was receiving high-dose glucocorticoid therapy for protein-losing enteropathy, and the risk of dehiscence was a concern following gastrotomy.13
This study has limitations related to its retrospective nature. Some dogs in which the technique was used but failed during the study period could have been missed if the use of the technique was not mentioned in the clinicians’ case log. This was, however, considered very unlikely but could have overestimated the success rate. The follow-up period was short except for one dog. Finally, although all dogs had an endoscopy report including descriptive images and text, it is possible that some complications related to removal, such as superficial erosions or discrete bleeding, were not reported because they were considered minor. In addition, the reports did not indicate the time required for each procedure, and only an estimate could be made for most cases.
Conclusion
Based on our results, the bottle liner technique should be considered before gastrotomy when gastric foreign bodies cannot be grasped with forceps or snares. The device is cheap and easy to make, and the technique is easy to implement in most dogs with few and minor complications expected.
The authors gratefully thank Dr. Anisha Jambhekar for assisting with the preparation of the manuscript.
Preparation of the bottle liner device. (A) Bottle liner, 4 oz (118 mL) Drop-Ins. (B) Placement of traction threads with a 30-gauge needle. (C) Bottle liner with traction threads attached at three points. (D) Bottle liner positioned at the end of the endoscope.
Steps of the bottle liner technique. (A) Lubrication of the outer surface of the bottle liner. (B) Introduction into the gastrointestinal tract. (C) Placement inside the antrum under endoscopy supervision. (D) Placement of the foreign body inside the bottle liner using forceps. (E) Foreign body inside the bottle liner before removing. (F) Removal of the baby liner by traction (endoscopic view). (G) Removal of the baby liner by traction (external view).
Examples of foreign bodies removed with the bottle liner. (A) Stone. (B) Piece of rubber. (C) Ball. (D) Pieces of plastic. (E) Dog toy (Kong Company, Golden, Colorado).
Contributor Notes
The online version of this article (available at jaaha.org) contains supplementary data in the form of one video.
