HSC Section 3 - Trauma, Critical Care and Sleep Medicine

J.H. Bird et al.

demonstrating air within the mediastinum or under the diaphragm. Lateral soft tissue of the neck XR may also demonstrate free air within the soft tissues of the head and neck. Oral contrast studies. Current opinion would suggest that barium studies are not accurate in detectingmucosal injury 25 and can cause an inflammatory response in the event of extravasation. Water contrast swallows can be used but are not as sensitive as barium when detecting perforations and may cause respiratory complications if aspirated. With development of CT imaging and superiority of endoscopy at detecting mucosal lesions, contrast X-ray studies have now been superseded in investigating caustic ingestion injury. 26 Computed tomography. To date, only one retrospective review by Lurie et al. 27 has compared CT imaging versus endoscopy in the acute setting. CT imaging was less sensitive than endoscopy in predicting mortality and predicting the need for surgery in those with caustic ingestion injury although this study only included 23 adults (level 3 evidence). CT may play a role in providing information in predicting the risk of stricture formation as published by Ryu et al. 28 Ryu found that sensitivity and specificity of CT (81.4% and 95.6%, respectively) were both greater than that of endoscopy (sensitivity of 62.8% and specificity of 84.8%). However, in the acute setting, endoscopy would appear to be the gold standard investigation (level 3 evidence). Endoscopy. Oesophagogastroduodenoscopy (OGD) is con- sidered the gold standard investigation when evaluating those with caustic ingestion injury. There are no controlled studies comparing the effectiveness of early versus late endoscopy; however, it appears to be accepted that endoscopy should take place within the first 24 – 48 h after ingestion, following clinical stabilization, although there is evidence delayed OGD at 48 – 96 h post-ingestion is safe as described by Zargar et al. 29 who described no complications as a result of OGD in patients up to 96 h post-ingestion (level 3 evidence). Caution must be taken if performing OGD after this time frame due to the friability and tissue softening during the healing period. An endoscopic classification system has been described by Zenger 29 (Table 1). Endoscopic classification is important for prognosis and management. Patients with grade 1 or 2A injuries have a good prognosis, and they do not develop outlet obstruction or strictures of the oesophagus. Approx- imately, 70 – 100% of patients with grade 2B and 3A injuries develop stricture. For patients with grade 3B injuries, a mortality of 65% has been reported, and in the majority of cases, oesophagectomy and colonic or jejunal replacement surgeries are required (level 3 evidence). 29

Table 1. Endoscopic classification of caustic injuries of the oesophagus Zargar et al. 29 Grade Features

0 1 2

Normal

Superficial mucosal oedema and erythema Mucosal and submucosal ulcerations Superficial ulcerations, erosions, exudates Deep discrete or circumferential ulcerations Transmural ulcerations with necrosis

2A 2B

3

3A 3B

Focal necrosis

Extensive necrosis

4

Perforations

Contraindications to OGD would be in those patients with respiratory distress, haemodynamic instability, sus- pected perforation or airway compromise secondary to severe laryngeal oedema. Indications for endoscopy. In those patients where the ingestion was intentional, positive endoscopy findings are more likely when compared to those with unintentional ingestion, often the paediatric population. 14,30 Drooling, dysphagia, vomiting, oral injury and pain are markers of high-grade injury, indeed Betalli et al. 31 as part of a multi- centre observational study found the presence of symptoms was the strongest predictor of severe oesophageal lesions (level 2 evidence). The absence of symptoms has also been found to correlate with no or low-grade injury at endoscopy (level 3 evidence). 30,32,33 These observational studies would suggest that it would be appropriate to refrain from investigation in those adults who are asymptomatic without clinical signs. A more cautious approach in the paediatric population should be considered where the history of ingestion is uncertain and a period of observation in those who are asymptomatic would be prudent if it is felt that acute endoscopy is not indicated. Keypoints. • Plain radiographs may help in the presence of suspected perforation. • OGD is the gold standard investigation. This allows the degree of caustic ingestion injury to be graded using Zenger’s classification and formulate an appropriate long-term management plan. • Contrast swallow investigations can cause extravasa- tion injury and do not interpret the degree of injury. • CT imaging in the acute setting is less sensitive than endoscopy in predicting mortality and predicting the need for surgery in those with caustic ingestion injury.

© 2016 John Wiley & Sons Ltd Clinical Otolaryngology 42 , 701–708

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