Foreign body esophagus and their management
Introduction:
Patients with FB in GI tract usually present to the emergency department of the hospital. FB of food passage are usually swallowed, either purposefully or accidentally. These patients usually provide accurate history including the nature of FB swallowed.
Since oropharynx is well innervated, patients can accurately localize oropharyngeal FB. Chronic FB can cause infections to surrounding soft tissue of throat and neck. Perforations of esophagus has also been documented due to FB.
Esophagus is a tubular structure of about 20-25 cm in length. FB lodged in the upper esophagus can be accurately localized by the patient, while those lodged in the lower two-thirds of the esophagus are poorly localized.
Anatomically normal esophagus has 3 areas of narrowing where FB could get lodged. These narrowed areas include:
1. Upper esophageal sphincter - Cricopharynx area where cricopharyngeus muscle acts.
2. Cross over of aorta - This area of upper esophagus is narrowed over the area over which cross over of aorta occurs. Aorta cause compression to esophagus while it crosses over it.
3. Lower esophageal sphincter
Among these three areas the upper esophageal sphincter is considered to be the narrowest portion of the entire GI tract.
In addition to the above specified normal anatomical narrowings, FB esophagus could get entrapped in the structural abnormalities of esophagus which could be:
1. Strictures
2. Webs
3. Diverticula
4. Malignancies
Motor disturbances involving esophageal musculature could cause entrapment of FB duee to esophageal spasm. Examples of this condition include: Scleroderma, achalasia charda, and diffuse esophageal spasm.
Etiology:
Accidental swallowing of objects, food bolus etc.
Young children often put objects they find to their mouths and may accidentally swallow them.
In adults the most common cause for GI FB involves food bolus. Accidental swallowing of FB like dentures are also common in adults. Psychiatric patients may swallow a wide variety of FB Adult alcoholics are more prone to FB in the food passage
Clinical presentation:
In children they include:
Irritability
Poor feeding
Drooling
Chest pain
Coughing
Diagnosis:
This can always be made from history.
Radiographs will reveal evidence of presence of radio opaque FB
Other indirect evidences of FB is also seen in X-ray soft tissue Ap / lat views. Particularly in lateral view, they include:
1. Presence of prevertebral shadow
2. Widening of prevertebral space. Soft tissue widening of prevertebral space is considered to be significant if it is more than 50% the size of the corresponding cervical vertebrae.
3. Presence of gas shadow in the prevertebral space. This could be due to entrapment of swallowed gas, abscess formation due to the presence of a long standing FB.
Complications:
1. Abrasions involving oropharynx and esophagus
2. Lacerations in the esophageal mucosa
3. Esophageal perforations
4. Abscess formation (Retropharyngeal abscess)
5. Pneumomediastinum
6. Mediastinitis
7. Esophageal necrosis / stenosis
Endoscopic anatomy of esophagus:
The esophagus is about 25 cm long and is a muscular tube lined by delicated non-keratinizing stratified squamous epithelium. It traverses the neck, superior and posterior mediastinum. In the neck it is located immediatly behind the trachea and anterior to the prevertebral fascia. It begins at the level of 6th cervical vertebrae. It is related laterally to the contentts of carotid sheaths and thryoid lobes.
In the superior mediastinum it veers slightly to the left before returning back to the midline. It then passes behind the aortic arch and to the right of the descending aorta until it reaches the inferior mediastinum where it passes anterior and slightly to the left of the aorta before traversing the diaphragm.
Anteriorly it abuts the trachea, right pulmonary artery, left main bronchus, and pericardium, left atrium.
Posteriorly it is related to the vertebrae, the thoracic part of aorta and diaphragm.
Management:
The following factors should be considered in the management of FB esophagus:
Type / location of ingested FB
Interval between ingestion and presentation
Age of the patient
Ingestion of caustic FB like button batteries should be considered to be emergency. Delay in managing these patients may lead to esophageal perforation.
Sharp metallic objects like pins, needles, razor blades and nails should always be removed under controlled operating room conditions.
Endoscopic removal of FB:
Rigid esophagoscope / upper esophageal speculum is used.
FB impacted at the level of cricopharynx should be removed using an upper esophageal speculum. This procedure can be performed either under local / General anesthesia. FB impacted in the esophagus should be removed using an esophagoscope.
General anesthesia is preferred to local anesthesia in removal of FB esophagus because it can cause adequate relaxation making the passage of the oseophagoscope smooth and atraumatic. Local anesthesia is ideal if flexible esophagoscope is used.
Balloon catheters can be used to extract impacted FB from esophagus. This method can be tried only if the ingested FB is single, smooth and radio-opaque. This procedure is performed by placing the patient in a head down position. A balloon catheter is passed nasally / orally under fluroscopic guidance past the FB. The balloon is inflated with a radio-opaque solution and the catheter is slowly pulled out along with the FB.
Rigid esophagoscopy:
The esophagoscope used is a smooth cylinderical stainless tube which is provided either with proximal or distal illumiantion. It has markings indicating the distance from the proximal portion of the tube etched on its outside. This helps in recording the distance of the pathological lesion in the esophagus from the upper incisors where the proximal portion of esophagoscope rests.
These scopes are ideally 25 cm long (about the length of the esophagus). It has smooth bevelled edges at its tip. This ensures smooth passage into the esophagus.
Indications for rigid esophagoscopy:
1. To look out for malignant lesions involving esophageal mucosa and to take biopsy from suspicious looking lesions
2. To exclude the presence of second primaries
3. Removal of FB from esophagus
4. Dilatation of esophageal strictures
5. To stent esophageal tumors
6. To exclude traumatic perforations in patients with penetrating injuries of neck
7. To inject esophageal varices
Chest x-ray should always be performed on all patients before esophagoscopy to rule out the presence of aortic aneurysm.
The procedure:
Position:
The patient is placed in supine position with neck hyperextended and the head slightly flexed (Boyce position). This brings the cervical spine into a straight line with the thoracic spine. The back of the head should receive adequate support on the operation table especially in old patients with limited spinal extension.
The surgeon sits at the head end of the table and the height of the table is adjusted to a comfortable height for the surgeon.
The upper teeth is covered with dental guard or a gauze piece.
Largest esophagoscope is selected. Aqueous gel is liberally applied over the esophagoscope. It is then inserted into the mouth, protecting the lips from injury with the fingers of non dominant hand. Thumb of the non dominant hand is used as a fulcurm for the esophagoscope to protect the teeth.
Keeping in midline, the scope is advanced till the posterior pharyngeal wall is identified. The esophagoscope is advanced along the posterior pharyngeal wall while maintaining the midline position.
Passing through the cricopharyngeal sphincter (upper esophageal sphincter) is the difficult step for an inexperienced surgeon. On insertion the scope comes to a dead stop and the pharyngeal lumen suddenly disappears as cricopharyngeal sphincter level is reached. Now the bevel of the scope should point upwards. The tip of the scope is elevated against the posterior surface of cricoid with the non dominant thumb. Steady firm pressure is applied against the contracted cricopharyngeus. The tip of the scope is advanced slowly keeping the lumen in view always.
In the presence off pharyngeal pouch (Zenker's diverticulum) it can easily be perforated as the scope would automatically enter the pouch. Care should always be taken to avoid this pitfall.
The scope is advanced down the cervical esophagus always keeping the lumen of esophagus in view. Metal suction tip can be used to suck out secretions. If FB is located it can be grasped and removed using a grasping forceps.
