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Definition

Fragmentation of the tube refers to complete structural failure of the tube, resulting in discontinuity of the tube.

Risk factors

 Repeated use of tubes

 Retroflexion into oral cavity

 Exposure to sunlight, chemical agents, or environmental extremes

Pathogenesis

Nasogastric tubes can fragment if they are brittle, have defects, or become retroflexed into the oral cavity. Nasogastric tubes can become brittle over time and with repeated use, especially if exposed to sunlight, chemical agents, or temperature extremes [10]. Tubes may also fragment if a horse chews on a tube which retroflexes into the oral cavity [6]. These fragments may remain within the esophagus or stomach.

Prevention

Nasogastric tubes should be frequently inspected to ensure that they are in good condition and without any defects or damage. Care should be taken to avoid oral retroflexion of nasogastric tubes and immediate correction, if it occurs. Awareness and prompt recognition of the problem may reduce the chance of complete transection of the tube. If the tube has been misdirected into the oral cavity, it should be removed and inspected for damage before continuing with nasogastric intubation.

Diagnosis

Once it is recognized that the tube is incomplete, it is essential to immediately locate the position of the fragmented segment of tube. This should include an oral examination, because some fragments may be retrieved orally [11]. If this is not successful, external palpation of the neck, endoscopic examination of the esophagus and stomach, and cervical and thoracic radiographs may locate the fragment [6, 11]. Multiple fragments may be present, so it is important that the entire tube is retrieved [10, 11].

Treatment

Treatment requires removal of the fragmented tube to prevent further gastrointestinal obstruction and trauma. The method of removal depends on the location of the tube, available equipment, and the success of each technique. Manual extraction from the oral cavity can be performed if the tube is located in the oral cavity and is facilitated by general anesthesia to allow safe and thorough manual exploration [11]. Homemade or commercially available snares can be used to endoscopically snare and retrieve tube fragments, either using standing sedation or general anesthesia [6, 10]. Surgical removal by esophagotomy or gastrotomy has been used in selected cases when other methods of retrieval were unsuccessful [6, 10].

Expected outcome

If nasogastric tube fragments are not removed, it is likely that they may cause future intestinal obstruction or injury and require emergency exploratory celiotomy (Figure 5.3).