Gastro-oesophageal reflux disease Aetiology

Normal competence of the gastro-oesophageal junction is maintained by the LOS. There has been considerable controversy about the relative importance of the physiology of the LOS and the anatomy of the cardia. This controversy is not completely resolved, but it is currently accepted that the most important factor in gastro-oesophageal competence is the function of the LOS, which is augmented by a normally functioning diaphragmatic hiatus.

Loss of competence of the LOS leads to gastro-oesophageal reflux disease (GORD). This rather clumsy name and inelegant acronym has come into common use because the alternatives do not describe the condition. Sliding hiatus hernia has a variable association with GORD. In general patients with the more severe stages of GORD tend to have a hernia, but most GORD sufferers do not have a hernia and many of those with a hernia do not have GORD. It should be noted that rolling or paraoesophageal hiatus hernia is a quite different and potentially dangerous condition (see below). Reflux oesophagitis is a complication of GORD that occurs in a minority of sufferers. It occurs in 40—50 per cent of those referred to hospital, but a much lower proportion of those who suffer from symptoms of GORD in the community as a whole.

A degree of gastro-oesophageal reflux is normal, partic­ularly after meals when there is a need to regurgitate swallowed air to maintain comfort. Physiological reflux mostly occurs during transient lower oesophageal sphincter relaxations (TLOSRs) that are quite separate from swallow-induced relaxation. In the early stages of GORD most of the pathological reflux occurs as a result of an increased number of TLOSRs. In severe GORD a greater proportion of reflux occurs across a LOS that has lost its basal tone and has a shorter length exposed to intra-abdominal pressure. Under­standing of the function of the LOS has been largely eluci­dated by Dent, who discovered the importance of TLOSRs. and by DeMeester, who clarified the importance of the basic competence of the LOS which is governed by basal LOS pressure, the overall length of the LOS and the length that is exposed to intra-abdominal pressure.

TLOSRs, the most important factor in gastro-oesophageal reflux

Length and pressure of the LOS is also important

In westernised countries GORD is by far the commonest condition affecting the upper G I tract. This is in part a rela­tive change due to the declining incidence of peptic ulcers as the incidence of infection with Helicobacter pylori has reduced due to improved socioeconomic conditions. How­ever, there has almost certainly been an absolute increase in the incidence of GORD in the last 20—30 years. The cause of the increase is unclear, but may be due in part to increasing obesity. In a curious way it may also be an effect of the reduced incidence of Helicobacter infection. Since chronic infection of the gastric corpus decreases acid secretion, and infection of the antrum increases acid secretion the overall effect of reduced infection on gastric acid secretion in the community is a matter of conjecture. Some suggest that the net effect is increased secretion that may increase the incidence of GORD. The epidemiology of upper G I disease is a fascinating topic of research that is evolving rapidly. It is a particularly important topic since medication for GORD is now the largest single item on the healthcare budget of many countries, and the incidence of cancer of the lower oesoph­agus and cardia is also increasing, possibly as a result of the changed incidence of GORD (see below).

Clinical features

Dyspepsia with fatty foods is more common in GORD than gallstone disease

Retrosternal burning pain (heartburn) and epigastric pain are the commonest symptoms. These are usually provoked by food, particularly fatty food. Indeed ‘fatty dyspepsia’ is a much more common feature of GORD than of gallstones with which the association is rather questionable. As the condition becomes more severe gastric acid may reflux to the mouth and produce an unpleasant taste. In gross cases food may reflux to the mouth and this can be a particularly trying symptom. It is in the more advanced cases there is a history of pain and reflux when lying flat or on stooping. A propor­tion of cases has odynophagia with hot beverages, citrus drinks or alcohol. This symptom which occurs within a few seconds of ingestion is a very useful confirmation that the patient is suffering from an oesophageal disorder and not a peptic ulcer. Some patients present with less typical symptoms such as angina-like chest pain, pulmonary or laryngeal symptoms. Dysphagia is usually a sign that a stricture has occurred, but may be caused by an associated motility disorder.

Because GORD is such a common disorder it should always be the first thought when a patient presents with oesophageal symptoms that are unusual or that defy diagnosis after a series of investigations.

Diagnosis

In the majority of cases the diagnosis is assumed rather than proven and treatment is empirical. Endoscopy is done mainly to exclude more serious pathology such as cancer. If the typi­cal appearance of reflux oesophagitis, peptic stricture or Barrett’s oesophagus is seen the diagnosis is clinched, but oesophagitis is not present in most cases. The endoscopic appearances of the normal oesophagus, hiatus hernia, oesophagitis and stricture are shown in Figs 50.24—3 0. In patients with severe or persistent symptoms in whom it is judged that an objective diagnosis is essential, oesophageal manometry and 24-hour oesophageal pH recording should be done. It is essential to have an objective diagnosis before embarking on an antireflux operation. It is important that manometry is done at the same sitting as a pH study since fermentation of food residue in an achalasic oesophagus produces lactic acid surprisingly rapidly, and a significant proportion of patients with achalasia has abnormal acid exposure of the lower oesophagus. Usually the form of the pH trace in achalasia is different from that of GORD with slow undulations of pH rather than rapid bursts of reflux.

However, the author has seen cases of achalasia with a pH recording identical to that of GORD and in whom the symptoms of achalasia have been completely relieved by Heller’s myotomy without a concurrent antireflux procedure and without the onset of GORD on prolonged follow-up.

Barium swallow and meal examinations give the best appreciation of gastro-oesophageal anatomy (Fig. 50.31). This may be important to the surgeon planning an operation that may be complicated by oesophageal shortening or a rolling hiatus hernia, but it is not important for the diagnosis of GORD. Radiology is at best 50 per cent accurate in the diagnosis of GORD so that one might just as well toss coins. The use of the Trendelenburg position may give good pic­tures, but does not help the assessment of reflux.

For the most part making a diagnosis of GORD is not difficult, but because it is so common there is a large number of people in whom the diagnosis is obscure. It should be borne in mind that proton pump inhibitors (PPIs), which are now quite properly in widespread use by family doctors, heal reflux oesophagitis rapidly so that there may be nothing abnormal to see at endoscopy. The effect of PPIs on acid secretion may be surprisingly prolonged, in some cases lead­ing to false-negative oesophageal pH studies. As a matter of routine, PPIs are stopped a week before oesophageal pH recording, but acid secretion is sometimes reduced for 2 weeks or more. In cases of doubt 24-hour pH recording should be repeated and it is sometimes useful to stop PPIs 4 weeks before pH recording.

Achalasia and GORD are easily confused

A further perversity in the diagnosis of GORD is the ease with which its symptoms may be confused with those of achalasia. With the more widespread use of oesophageal manometry achalasia is often diagnosed at a much earlier stage than previously, long before the classic symptom pat­tern is established and long before the classic X-ray appear­ances are seen. It is perhaps surprising that the early symptoms of achalasia may be indistinguishable from those of GORD even with hindsight. This is especially important when patients are being considered for antireflux surgery.

Management of uncomplicated GORD

Medical management

Most sufferers from GORD do not consult a doctor and do not need to do so. They self-medicate with over-the-counter medicines such as simple antacids, antacid-alginate prepara­tions and H2 receptor antagonists. Consultation is more like­ly when symptoms are severe or prolonged. By the time a patient comes to consultation, and particularly hospital con­sultation, it is highly likely that simple treatment will have been tried and found wanting. Nevertheless it is always worth checking. Simple measures that may have been neg­lected include advice about weight loss, smoking, excessive consumption of alcohol, tea or coffee and a modest degree of head up tilt of the bed. Tilting the bed has been shown to have an effect that is similar to taking an H2 antagonist. However, the common practice of using additional pillows has no significant effect apart from causing discomfort.

PPIs are the most effective medication for severe GORD

PPIs, such as omeprazole, lansoprazole and pantoprazole are by far the most effective drug treatment for GORD. Indeed they are so effective that, once started, patients are very reluctant to stop taking them. The PPIs have been a major advance in the treatment of CORD. Given an adequate dose oesophagitis heals in the majority of cases and even most strictures respond well to one or two dilatations and long-term PPI treatment. The only reservation is whether there will be serious side effects with long-term consumption. Thus far the PPIs have an excellent safety record, but doubts have been expressed as to whether the increased incidence of adenocarcinoma of the lower oesophagus and cardia in many countries may be due in part to the long-term treatment of GORD with powerful acid suppression.

Surgery

Strictly speaking the need for surgery should have been reduced since medication has improved so much. Paradoxically, the number of antireflux operations has remained rela­tively constant and may even be increasing. This is probably partly due to increased patient expectations and partly to the advent of minimal access surgery that has improved the acceptability of surgical procedures.

The results of antireflux surgery are generally good

The indication for surgery in uncomplicated GORD is essentially patient choice. The risks and possible benefits of surgery need to be discussed in detail. The risks include a small mortality rate (0.1—0.5 per cent, depending on patient selection), the risk of a failed operation (5—10 per cent) and the risk of side effects such as dysphagia, gas bloat or abdomi­nal discomfort (10 per cent). With current operative tech­niques 85—90 per cent of patients should be satisfied with the result of an antireflux operation. Patients who are asymptomatic on a PPI need a careful discussion of the risk side of the equation. Those who are symptomatic on a PPI need a careful clinical review to make sure that they will benefit from an operation. Reasons for failure on a PPI include ‘volume’ reflux (good indication for surgery), ‘hermit’ life­style in which the least deviation from lifestyle rules leads to symptoms (good indication), psychological distress with intolerance of minor symptoms (bad indication — these patients are likely to be dissatisfied with surgery), poor com­pliance (good indication if the reason for poor compliance is the side effects  of treatment, otherwise bad indication) and misdiagnosis of GORD. Clinical trials are now in progress to compare the relative efficacy of long-term medication and surgery, and it is hoped that the results will simplify clinical decision making.

What operation?

There are many operations for GORD, but essentially the choice is between total and partial fundoplication. The major types of antireflux operation were all developed in the 1950s (Fig. 50.32). Anatomical repair of hiatus hernia has been abandoned as it is ineffective. Nissen described total fundoplication in which the fundus of the stomach is wrapped completely around the lower oesophagus. The Belsey operation is a thoracic procedure in which the oesophagus is sutured to the diaphragm and to the fundus of the stomach to reduce any hiatus hernia and produce a 2400 anterior fundoplication. The Hill procedure is an operation in which the cardia is tightened and fixed to the pre aortic fascia. The completed operation looks very like a fundoplication.

Total or partial fundoplication?

Done correctly these are all effective operations. The disadvantage of the Nissen fundoplication is that that it can produce an overcompetent cardia resulting in dysphagia or the gas bloat syndrome in which belching is prevented. As a result the stomach fills with air and the patient feels very full after meals and passes excessive flatus. The problem of the overcompetent cardia has been largely overcome by the floppy Nissen in which the fundoplication is made very loose around the oesophagus and also by making a short fundo­plication of 1 cm or so. Partial fundoplication is less prone to side effects, but has tended to have a higher recurrence rate. This tendency seems to have been partly overcome by improved suture materials. There are now many different partial fundoplication operations, but the principles of anti­reflux surgery remain the same.

The Angelchik prosthesis is a different type of antireflux procedure in which a silastic prosthetic collar is placed around the lower oesophagus. It probably acts by limiting distension of the cardia which is the trigger zone for TLOSRs and undoubtedly prevents reflux in the majority of cases in which it is implanted. However, it has a tendency to cause troublesome dysphagia and is much less popular than formerly.

  Roux-en-Y diversion reduces reflux

In some complicated cases, such as re operative problems, the effects of reflux can be greatly reduced by performing a partial gastrectomy with a Roux-en-Y reconstruction. This reduces gastric acid secretion and diverts bile and pancreatic secretions away from the stomach. Thus the volume of potential refluxate in the stomach is reduced and because of its changed composition it is less damaging to the oesophagus.

What operative approach?

For many years the relative merits of the thoracic and abdominal approaches were hotly debated. The advent of minimal access surgery has overshadowed this debate and most antireflux operations are now done with a laparoscopic approach. A small number of surgeons has used a thoraco­scopic or video-assisted thoracic approach. In general the abdominal approach is preferred unless there is a particular indication for opening the chest for safe surgery. Nowadays this is seldom required since there are excellent on-table retractors that allow access to the upper abdomen and lower mediastinum if necessary.

Laparoscopic fundoplication

Five cannulae are inserted in the upper abdomen (Fig. 50.33). The cardia and lower oesophagus are separated from the diaphragmatic hiatus. The fundus may be mobilised by dividing the short gastric vessels that tether the fundus to the spleen. The hiatus is narrowed by sutures placed behind the oesophagus. The fundus is drawn behind the oesophagus and then sutured in front of the oesophagus. In the Nissen fundoplication fundus is sutured, to fundus to encircle the oesophagus completely (Fig. 50.34a). In the Toupet partial fundoplication, which is a popular procedure, the fundus is sutured to the oesophagus on each side leaving a strip of exposed oesophagus anteriorly (Fig. 50.34b). If the operation cannot be completed safely or effectively by the laparoscopic method the abdomen is opened with an upper midline incision and the procedure is completed.

Complications of GORD 

Stricture

Reflux-induced strictures (Fig. 50.30) are common, usually in late middle age and the elderly, but they may occur even in children. It is important to distinguish a benign reflux-induced stricture from a carcinoma. This is nor usually difficult, but sometimes a cancer spreads under the oesophageal mucosa at its upper margin producing a surprisingly benign looking stricture on first sight.

Day-case dilatation and PPI for peptic stricture

Peptic strictures generally respond well to dilatation and long-term treatment with a PPI. Since most of the patients are elderly antireflux surgery is not usually considered. However, it is an alternative to long-term PPI treatment just as in uncomplicated GORD in younger and fitter patients. It should be borne in mind that antireflux surgery may be difficult technically in stricture patients because of associated oesophageal shortening.

 Oesophageal shortening

With long-standing reflux oesophagitis the oesophagus has a tendency to contract longitudinally producing a secondary hiatus hernia. This does not matter in a patient being treated by medication, but it may cause difficulty during antireflux surgery. The shortening may be a minor problem that simply requires mobilisation of the oesophagus. If a good segment of intra-abdominal oesophagus cannot be restored without tension a Collis gastroplasty can be done (Fig. 50.35). This produces a neo-oesophagus around which a fundoplication can be done (Collis—Nissen operation).

Barrett’s oesophagus (columnar-lined lower oesophagus)

Barrett’s oesophagus is a metaplastic change in the lining mucosa of the oesophagus in response to chronic gastro­oesophageal reflux (Fig. 50.36). One of the great mysteries of GORD is why some people develop oesophagitis and others develop Barrett’s oesophagus often without significant oesophagitis. In Barrett’s oesophagus the junction between squamous oesophageal mucosa and gastric mucosa moves proximally. It may be difficult to distinguish a Barrett’s oesophagus from a tubular sliding hiatus hernia during endo­scopy since the two often coexist (Fig. 50.37). The key is where the gastric mucosal folds end. The mucosa in the body of the stomach has longitudinal folds. The columnar lining in Barrett’s oesophagus is smooth. If a peptic stricture occurs in Barrett’s oesophagus it always occurs at the new squamo­columnar junction (Fig. 50.38). A different type of stricture may occur in the columnar segment after healing of a Barrett’s ulcer (see below).

Intestinal metaplasia, the important factor

Several types of gastric-type mucosa may be found in the lower oesophagus. When intestinal metaplasia occurs there is an increased risk of adenocarcinoma of the oesophagus of the order of 25 times that of the general population (Figs 50.39 and 50.40). Patients who are found to have Barrett’s oesophagus may be submitted to regular screening endoscopy with multiple biopsies every year or two in the hope of finding dysplasia or in situ cancer rather than allowing invasive cancer to develop and cause symptoms. There is as yet no general agreement about the benefits of screening endoscopy, nor about the ideal frequency of endoscopy. A significant problem is that the incidence of Barrett’s oesophagus in the community is estimated to be at least 10 times the incidence discovered by endoscopy in dyspeptic patients referred for endoscopy. Thus adenocarcinoma in Barrett’s oesophagus often presents with invasive cancer without any preceding reflux symptoms.

Until recently Barrett’s oesophagus was not diagnosed until there was at least 3 cm of columnar epithelium in the distal oesophagus. With the better appreciation of the importance of intestinal metaplasia Barrett’s oesophagus may be diagnosed if there is any intestinal metaplasia in the oesophagus.

When Barrett’s oesophagus is discovered the treatment is that of the underlying GORD. Several methods of ablation of Barrett’s mucosa are under active study, including laser, photodynamic therapy and argon beam plasma coagulation. In conjunction with high-dose PPI treatment or an antireflux operation these endoscopic methods can restore the squa­mous lining of the oesophagus. It is not yet known whether this reduces the risk of malignant transformation since there are often remnants of glandular mucosa underneath the new squamous lining.

  Don’t confuse Barrett’s ulcer with oesophagitis

Barrett’s ulcer is an ulcer in the columnar-lined portion of a Barrett’s oesophagus (Fig. 50.41). These are distinct from the more usual erosions of reflux oesophagitis that always occur at or just above the squamocolumnar junction. Barrett’s ulcers may be deep and prone to bleeding or, rarely, perforation. Uncomplicated reflux oesophagitis almost never gives rise to severe haemorrhage.