Passing an oesophagoscope, even more so than passing a bronchoscope, might be considered to be outside the range of Primary Surgery. It is however the easier of these two procedures. An oesophagoscope looks like a bronchoscope except that it has no side tube for oxygen, and no ventilation holes at its distal end, because the patient does not need to breathe through it.

Fortunately, most ingested foreign bodies pass through the gut, but if they stick, they have to be removed. 90% stick in its upper 5 cm, just below the cricopharyngeus muscle before the oesophagus enters the thorax. This is fortunate, because this is the easiest place from which to remove them. They are commonly coins, buttons, safety pins, or bones. The patient may have almost no symptoms, or he may be distressed, refuse food, drool saliva, choke, gag, or cough (typically in paroxysms). If he is a child he may merely ''fail to thrive'. If he is older, he may complain of pain, or the sensation of a foreign body behind his sternum. If it is large enough to compress his trachea, he may have stridor, or episodes of cyanosis and recurrent pneumonitis (unusual). If he is very young, or mentally incompetent, there may be no history that he has swallowed anything. Symptoms may have lasted hours or years. The diagnosis is usually obvious, but a foreign body which is missed, can cause persistent dysphagia and loss of weight, so that you may suspect a carcinoma.

A TRUE STORY. The examining surgeon at a nurse's training school (St Francis Hospital, Katete, in its early days): ''What instrument would you use for oesophagoscopy?'' Enrolled nurse: ''A sigmoidoscope''. When it was explained that this was wrong, she repeated (correctly) that this was indeed the instrument that she had seen used at her rural hospital! LESSON If necessary improvise. OESOPHAGOSCOPE, (a) infant, (b) child, (c) adult, with forceps and suckers that are long enough to go through them. One only of each. If you don't have an oesophagoscope, you may be able to use a bronchoscope to remove coins from the oesophagus, or bougie a carcinoma, before passing a Celestin tube. The more protruding beak of a bronchoscope is, however, more likely to perforate the oesophagus.

BOUGIES, oesophageal, neoprene, standard set, alternate sizes only, one set only. The old fashioned gum elastic ones are satisfactory.

Fig. 25-10 POSITIONING THE HEAD FOR OESOPHAGOSCOPY. A, the difficult part is passing the patient's cricopharyngeus. This will be easier if you keep the handle of the instrument up, so that it slides over this muscle. B, keep his head on a pillow with his neck flexed and his head extended in the ''sniffing position'. This position will allow you to oesophagoscope him as far as the deepest part of his thoracic kyphosis. C, introduce the oesophagoscope obliquely and move it vertically, as it reaches his pharynx. D, if you need to examine the lowest part of his oesophagus (less often necessary), straighten or slightly extend his neck, until he is in the sword-swallowing position. E, a bronchoscope is circular, and has air holes. F, an oesophagoscope is oval, and has none. Adapted from ''Hamilton Bailey's Emergency Surgery', edited by HAF Dudley, Figs. 22.1 and 22.3. John Wright, with kind permission.

THE SECRET IS TO FLEX HIS NECK AND EXTEND HIS HEAD OESOPHAGOSCOPY INDICATIONS. (1) The removal of foreign bodies. (2) To check the nature of a stricture, whether fibrous or malignant after a barium swallow, and to take a biopsy. (3) Bouginage for carcinoma of the oesophagus. (4) Bouginage for a stricture.

ANAESTHESIA. (1) General anaesthesia with a short-acting relaxant and tracheal intubation. (2) Ketamine is a poor second.

POSITION. Keep the patient's head on a pillow throughout. This will flex his neck. Then extend his head on his neck to bring him into the ''sniffing position' shown in A 13- 7. This position will allow you to pass the oesophagoscope into the deepest part of his thoracic kyphosis. The most common reason for failure is insufficient flexion of his neck, and extension of his head.

If you need to view the very lowest part of his oesophagus (unusual), straighten, or slightly extend, his neck, so that his pharynx and his oesophagus are in a straight line to let the oesophagoscope pass (the ''sword-swallowing position'). Otherwise, keep it flexed. If your table does not have a headpiece that drops down, ask an assistant to hold his head over the end of the table, to control its movement[md]this is not easy, and is dangerous!

INSERTION. Aim the oesophagoscope vertically downwards at his uvula. Angle it so as to pass the base of his tongue (aim at the foot of the pedestal of the table). When his larynx comes into view, avoid the midline, and pass it laterally, through one or other pyriform fossa, to reach his oesophagus, which is again in the midline.

Going through his cricopharyngeus is the difficult part. It should look like the the anus: aim for the centre of the pit. If you have difficulty, pass a tube or bougie first, and use this to guide the oesophagoscope through.

CAUTION ! (1) Never advance the oesophagoscope blind, or you may perforate his oesophagus. (2) Keep the lumen of his oesophagus in the centre of your field of view, as you slide the instrument down.

OESOPHAGOSCOPY [s7]FOR REMOVING A FOREIGN BODY THE X-RAY DIAGNOSIS may be straightforward, if the foreign body is opaque. In the oesophagus coins lie in the coronal plane, so that you see their full diameter in a PA film. In the respiratory tract they lie sagittally, so that you see them end-on. A barium swallow may be useful, but it makes oesophagoscopy soon afterwards more difficult; diatrizioate meglumine (''Gastrografin') is better.

CAUTION ! (1) A normal X-ray does not exclude a radiolucent foreign body. (2) If he has swallowed a foreign body that may cause trouble, X-ray his whole abdomen and his pelvis also.

METHOD. First try laryngoscopy. You may be able to feel the foreign body with a probe, and remove it with a long clamp.

If laryngoscopy and simpler methods fail, pass the oesophagoscope, as above. As soon as you can see the foreign body clearly (usually a coin), pass the biopsy forceps and grasp it firmly. If it moves distally, withdraw the forceps, pass the oesophagoscope a little further, and try to grasp it again. When you have grasped it, bring it and the oesophagoscope out together.

CAUTION ! (1) The great danger is perforating his oesophagus: (a) usually at the level of his cricopharyngeus, which keeps the entry closed, or (b) at a lower level where the foreign body impacts[md]beware of his aorta! (2) Safety pins, bones, and lumps of food, such as meat, should, if possible, be removed by an expert[md]they are particularly difficult, and dangerous. (3) Don't advance the oesophagoscope, if you cannot see the lumen of his oesophagus beyond it.

DIFFICULTIES [s7]WITH OESOPHAGOSCOPY FOR REMOVING A FOREIGN BODY If you DON'T HAVE AN OESOPHAGOSCOPE, you may be able to use a sigmoidoscope (as the nurse saw done in the story above). After you have identified his cricopharyngeus, use the obturator to negotiate it. If the foreign body is blunt, you may be able to pass a Foley catheter beyond it, inflate the balloon and pull it out with that (difficult).

If a FOREIGN BODY IS TOO LARGE TO REMOVE WHOLE, as with an impacted denture, you may be able to break it and remove the pieces.

If you FAIL TO REMOVE A FOREIGN BODY, refer him, probably for its open removal through the side of his neck.

If, soon after he is back in the ward, he develops PAIN in his neck, behind his sternum, or in his back, with dyspnoea, suspect PERFORATION OF HIS OESOPHAGUS. Look for air in his neck, pleural cavity or mediastinum (the earliest sign is a translucent crescent overlying the aortic knuckle). Consider giving him some contrast medium (''Gastrografin' not barium) and taking another film. Refer him for an immediate pharyngotomy (if the tear is in his cervical oesophagus) or thoracotomy. Delay is likely to be fatal.

If the above symptoms are delayed, he has FEVER and his chest X-ray is normal, suspect MEDIASTINITIS. Antibiotic treatment is more likely to succeed. Do a temporary gastrostomy to rest the abrasion in his oesophagus.

If an EMPYEMA develops, evacuate all fluid and air, insert intercostal drains (65-2), give him nothing by mouth, and consider a feeding jejunostomy (9.7, a gastrostomy is less effective because feed can reflux into his oesophagus).

If he develops a RETROPHARYNGEAL ABSCESS, treat him as in Section 5.7.

If he develops a STRICTURE, treat him as in Section 25.15.

OESOPHAGOSCOPY [s7]FOR INVESTIGATING A STRICTURE Pass the instrument with care, using one of small diameter first. Suck out and advance the instrument under direct vision. If entry is easy, and vision is poor, with a small instrument, withdraw it, and try a larger one. Continue distally under direct vision, until you see the lesion, sucking out any fluid you find.

OESOPHAGOSCOPY [s7]FOR CARCINOMA OF THE OESOPHAGUS Give him a general anaesthetic and a short-acting relaxant, intubate him, and control his ventilation. Pass the oesophagoscope, suck out the debris, then pass it further distally. Try to dilate him with graduated bougies. Take two biopsies for histology.

Fig. 25-11. GASTRIC LAVAGE is urgent if a patient has swallowed a corrosive substance. After ''Hamilton Bailey's Emergency Surgery', edited by HAF Dudley, John Wright, with kind permission.