Critically ill patients are often unable to maintain adequate nutritional intake to meet their metabolic needs. Therefore, nutritional support is often provided to these patients as part of their medical care (Padilla et al, 2016) most commonly provided via a nasogastric tube.
The most prevalent complications associated with the use of nasogastric tubes for providing enteral nutritional support include respiratory problems and diarrhoea (Gil-Almagro and Carmona-Monge, 2016). Digestive bezoars are uncommon; oesophageal bezoars are rare (Tawfic et al, 2010). Gastro-oesophageal reflux results in gastric acid and nutrient solution entering the oesophagus. If the oesophageal contents cannot be emptied quickly, long-term food retention forms hard oesophageal bezoars from the action of refluxed gastric juice and nutrient solution (Tawfic et al, 2010).
This article discusses a case of nasogastric tube obstruction and the occurrence of two oesophageal mucosal tears—serious iatrogenic injuries resulting from nasogastric tube reinsertion.
Case description
A 78-year-old woman was admitted to the authors' hospital with pneumonia. She had previously experienced a cerebral infarction. Emergency tracheal intubation was performed because her heart rate was significantly elevated, her blood oxygen saturation had progressively declined, and she exhibited shortness of breath. After intubation, she was put on a ventilator and sedated. A nasogastric tube was subsequently inserted to provide enteral nutrition. On day 6 after admission to the hospital, the endotracheal tube was removed and a percutaneous tracheostomy and tracheal catheter implantation were performed; the patient remained on the ventilator. On day 16, the nasogastric tube became blocked and the junior charge nurse attempted to reinsert it. The nasogastric tube was reinserted approximately 25 cm before encountering resistance. The junior nurse attempted to rotate it before reinsertion, but this was not effective. A senior nurse then attempted the same procedure, but encountered resistance after the nasogastric tube was inserted by approximately 35 cm. After these unsuccessful insertion attempts, blood stains could be seen at the front end of the nasogastric tube. To better investigate the causes of these blood stains, the doctor on duty performed an urgent bedside gastroscopy.
Gastroscopy results
During gastroscopy, a large amount of yellow, slightly hard, sediment (identified as foreign bodies) was seen in the lumen of the oesophagus (Figure 1). These bezoars were incrementally removed using foreign body forceps and a foreign body net until the forceps could enter the stomach (Figure 2).
A tear of the oesophageal mucosa was observed 24–25 cm from the patient's incisor teeth, with a small number of blood crusts on the surface and no obvious bleeding; 15 haemostatic clips were used for suturing (Figure 3). Another oesophageal mucosal tear was observed 35–37 cm away from the incisor teeth, and a small amount of blood oozed from the tear (Figure 4). Ten haemostatic clips were used for suturing.
Subsequent patient care
The nasogastric tube was successfully inserted under endoscopic guidance and feeding continued without further problems. On day 23, the patient was transferred to another hospital, at the request of her family.
Discussion
In the present case, the oesophageal lumen was blocked by oesophageal bezoars, which occurred on day 16 after the start of enteral nutrition. Oesophageal bezoars may have occurred because the length of the nasogastric tube was insufficient, or because there were postural management problems when feeding (this is often associated with reflux to the oesophagus), and the use of opioids and/or sedatives that delay gastric emptying may be another reason (Gil-Almagro and Carmona-Monge, 2016).
Delayed gastric emptying, gastric stasis, and reduced gastric acid are the main risk factors for the formation of gastrointestinal bezoars, according to Degheili et al (2017). They also point out that:
‘Previous gastric surgery including partial gastrectomy, gastrojejunostomy, pyloroplasty, peptic ulcer, achalasia, gastrointestinal malignancy, Crohn's disease, hypothyroidism, hiatal hernia, and neurotrophic or myotonic dystrophy in elderly patients [are risk factors].’
In future cases of oesophageal bezoars, it is important to consider the following:
Symptoms of oesophageal bezoars often manifest as pain and discomfort behind the sternum and difficulty in swallowing. Thus, it is difficult to diagnose and differentiate them from other conditions (Zhang et al, 2013). In the present case, the patient was admitted to hospital with pneumonia and no relevant examinations took place to determine whether the patient already had a partially formed bezoar that had affected her swallowing leading to aspiration.
In this case, the tears in the oesophageal mucosa were due to mechanical damage. Therefore, in cases of oesophageal obstruction, blind tube placement should be avoided because it may result in serious complications, such as oesophageal mucosal injury and severe oesophageal bleeding (Numata et al, 2018).
It is important to increase nurses' knowledge and awareness of bezoars and best practice when encountering resistance on nasogastric tube insertion. There are some key factors/symptoms that may indicate to the nurse that a patient is at an increased risk of bezoar formation. For example, patients with a past medical history of gastro-oesophageal reflux disease (GORD) may be more susceptible to this and may present with already formed bezoars. Additional causes of oesophageal bezoars include a history of gastrointestinal surgery (Ben-Porat et al, 2016), and use of hygroscopic gum laxatives, which may form a thick coagulum when ingested with a small amount of water. Simple phytobezoars (indigestible plant material) attributable to persimmon and pumpkin seeds have also been reported (Kement et al, 2012). Another study has shown oesophageal bezoars resulting from enteral feeding (Tawfic et al, 2012). Knowledge of this would help the nurse to be more aware of the risk of the presence of bezoars in specific patients. In addition, it is important that if resistance is encountered when inserting a nasogastric tube, the tube should be slightly withdrawn and gently reinserted; the process should not continue if resistance is encountered (Best, 2016). This was confirmed by Lister et al (2020). However, for the safety of patients, gastroscopy should be performed as early as possible to identify the possible cause of resistance.
Conclusion
In the present case, the patient developed oesophageal bezoars in an unusually short period. When providing enteral feeding for coma patients, if the flow of feed down the nasogastric tube slows gradually, or the tube becomes blocked, it is important to consider oesophageal bezoars as a possible cause of the obstruction. Furthermore, multiple attempts to reinsert the nasogastric tube resulted in two oesophageal mucosal tears in the case of the patient in this article, which required the medical team to perform a gastroscopy to investigate the cause of these tears and subsequent bleeding. The authors suggest that increased nursing knowledge and awareness of bezoars is needed, and the nasogastric tube should not be pushed if resistance is felt during insertion. Rotating the nasogastric tube and pushing against resistance as described in this case study should be avoided, as these were the most likely causes of the patient's oesophageal tear. Thus, it may be better to perform a gastroscopy immediately when resistance is encountered to identify the cause and then provide further treatment.