218 28 October 1967

Current Practice

DISEASE OF THE DIGESTIVE SYSTEM

Hiatus Hernia

MICHAEL ATKINSON,* M.D., F.R.C.P.

Gastro-oesophageal reflux is one of the commonest causes of

dyspepsia in this country and is usually due to hiatus hernia.

Yet many clinicians still in the prime of their careers were

trained before the syndrome of gastro-oesophageal reflux or the

significance of hiatus hernia was generally appreciated, and

20 years ago these received little attention in the medical

curriculum. It is hardly surprising that today hiatus herniais often overlooked, and it is worth restating the ways in whichit may present.

Types of Hernia

On anatomical grounds hiatus hernia is commonly dividedinto three types.

The sliding type is most frequently encountered, and herethe oesophago-gastric junction moves up through the hiatusinto the chest producing a bell- or funnel-shaped configuration.These hernias present with symptoms of gastro-oesophagealreflux, and though they are often quite small and reducible theseverity of symptoms bears no relation to their size or mobility.Only when oesophagitis has caused much fibrosis is the oeso-

phagus shortened, and hence " short oesophagus " is virtuallyalways the consequence and not the cause of the hernia.The para-oesophageal variety is characterized by herniation

of the fundus of the stomach and gastro-colic omentum throughthe hiatus alongside the cardia, which retains its normal position.This is the least common variety and often produces fewsymptoms. It may be impossible to distinguish from hernia-tion through a diaphragmatic defect separate from but closeto the oesophageal hiatus-which is not of course a true hiatushernia yet is believed by many to be the usual origin of thistype of hernia.The mixed variety is far commoner than a true para-

oesophageal hiatus hernia, with which it is often confusedbecause of difficulty in determining the positions of the cardia

relative to the hiatus. Here the symptoms are usually those of

gastro-oesophageal reflux, though many remain silent. Symp-toms of obstruction may occur, since the cardia lies above the

diaphragmatic hiatus-the herniated portion of the stomach

may become distended with food if the hiatus is small.

Causation of Hiatus Hernia

Hiatus hernia is usually an acquired condition, the causes of

which are still incompletely understood. Unlike other abdo-

minal hernias it is seldom clearly related to trauma or to sudden

muscular straining increasing intra-abdominal pressure. Very

occasionally a patient does feel a sharp tearing retrosternal pain

on straining shortly before symptoms of gastro-oesophageal

reflux commence, but it seems probable that this is a separate

entity from the common type of hiatus hernia, and it usually

occurs in younger subjects.

* Consultant Physician, Worcester Royal Infirmary.

At one time congenital laxity of the diaphagmatic hiatus was

believed to be the basic abnormality causing hiatus hernia.

However, hernia is not common after diaphragmatic paralysis,when the hiatus might be expected to be lax, which casts doubtupon this view. Perhaps of greater causative importance is

impairment of the normal anchoring mechanism of the stomach.The role of the phreno-oesophageal ligament has been stressedby surgeons. It is normally a diaphanous structure which may

atrophy with advancing age, permitting herniation to occur.

Loss of muscle tone in the stomach may facilitate the upwardpassage of the cardia through the hiatus; this would explainthe increased incidence of hiatus hernia in progressive systemicsclerosis, in which the musculature of the alimentary tract

becomes atonic. After partial gastrectomy the mobility of theremaining portion of the stomach is increased, and this mightwell account for the frequency of small hiatus hernias andsymptoms of reflux after this procedure.

Hiatus hernia may appear during pregnancy but disappearagain after delivery, suggesting that it is not a congenital abnor-mality but one acquired as a consequence of the upward dis-placement of the stomach and possibly of hormonally inducedgastric muscle hypotonicity occurring during pregnancy.

Clinical Presentation

Hiatus hernia may exist without producing symptoms, and ithas been estimated that in only 250% of cases are these severe

enough to cause the patient to seek medical advice. Thisaccords well with the frequent finding of asymptomatic hiatushernia on barium meal examination done for some other dis-order. Furthermore, symptoms may abate spontaneously forlong periods or even permanently, which of course makes assess-

ment of the results of therapy difficult. Fluctuations in bodyweight and emotional state may determine their presence or

absence or the disability they may cause.

Symptoms when present are usually caused by gastro-oesophageal reflux and its consequences, but with larger hernias

obstructive symptoms may be encountered at the level of the

diaphragm.

Gastro-oesophageal Reflux

These symptoms usually dominate the clinical picture in

patients with sliding hiatus hernia. Most of the populationhas had occasional heartburn, belching, or acid-tasting fluid

rising into the mouth at one time or another, and it is difficult

on occasions to distinguish the point at which these become

pathological.Heartburn and Chest Pain.-Heartburn is a word com-

monly used by patients to describe a burning discomfort in the

front of the chest sometimes radiating up into the neck or into

the interscapular region. Many will deny that the discomfort

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28 October 1967 Hiatus Her

amounts to pain, but others experience severe pain, which maybe difficult to distinguish from cardiac pain. The posturalrelationships of the pain are useful diagnostic pointers. Oeso-phageal pain often wakes ihe patient at night, and many havelearned by experience that this can be corrected by sleepingpropped up on pillows. Stooping or bending forward-whenweeding the garden, sitting behind the wheel of a car, or infront of a television set-are characteristic aggravating factors.Swallowing hot or irritating fluids may aggravate the pain.The differentiation of oesophageal from cardiac pain is not

always easy, and the consequences of error are serious. Nosingle feature of the pain provides a completely reliable guide,and the clinician must consider many factors in the historyin coming to a diagnosis. The character of the pain is of somevalue, since oesophageal pain is commonly burning, whilecardiac pain is often constricting in character.

Oesophageal pain may radiate to the arms, but pain downboth arms is most frequently cardiac in origin. Pain broughton by emotional stress is as likely to be oesophageal as cardiac,and pain occurring after a heavy meal might well be anginal.Relief by antacids points strongly towards an oesophagealsource for pain, but amyl nitrite seldom relieves oesophagealpain. If in doubt it is wise to assume that the pain is cardiac,at least for the first few days, bearing in mind however thatrecumbency and anticoagulant therapy may aggravate refluxoesophagitis and on occasion precipitate bleeding from theinflamed oesophageal mucosa.Acid regurgitation into the mouth is a less common mani-

festation of gastro-oesophageal reflux, because the presence ofgastric juice in the gullet frequently evokes a secondary peri-staltic wave which sweeps it back into the stomach. Likeheartburn, acid reflux has a postural relationship, occurring inrecumbency or on stooping, and in its mildest form causes onlya sour taste in the throat on waking. When more severe, largequantities of acid-tasting fluid rise into the throat without thephysical effort of retching or straining. If regurgitation iscopious choking attacks may wake the patient at night andaspiration pneumonia can occur.

Belching often complicates gastro-oesophageal reflux inhiatus hernia and usually results from air-swallowing to relieveheartburn. It may at times cause abdominal discomfort fromdistension and excessive flatus.

Anaemia and BleedingInflamed oesophageal mucosa is friable-as every endoscopist

knows. When the mucosa is inflamed the passage of foodthrough the gullet may induce bleeding of sufficient degreeeventually to cause anaemia. Furthermore, tablets of aspirinor phenylbutazone may remain in contact with the inflamedmucosa for a long enough period to induce bleeding and mayprecipitate haematemesis or melaena in patients with hiatushernia.One of the difficulties which may impede clinical diagnosis

is the frequent paucity of dyspeptic symptoms in patients withreflux oesophagitis severe enough to cause bleeding. The bleed-ing may be intermittent, and therefore occult blood tests on thestools are not always positive. Hence refiux oesophagitis isoften overlooked in elderly patients with iron deficiency anaemiaand the diagnosis can only be verified directly by oesophag-oscopy-which of course is not free from risk in the patientsin this age group.A further cause of acute bleeding in patients with hiatus

hernia is a mucosal tear at the cardia (Mallory-Weiss syndrome).The presence of a small sliding hernia appears to predispose tothe occurrence of such tears, presumably because this part ofthe stomach is then exposed to the considerable abdomino-thoracic pressure gradient which occurs during retching andvomiting.

niia-Atkinson B~DINm 219ia Atkinson ~~~~~~MEDICAL JOURNAL 9

Dysphagia

Dysphagia in hiatus hernia may be caused by stricture for-mation or less frequently by muscle spasm. Stricture is easilythe most serious complication of reflux oesophagitis and ischaracterized by constant dysphagia in contrast to the muchmore variable difficulty encountered in patients with oeso-phageal spasm. The development of a tight stricture usuallyresults in cessation of heartburn or acid reflux into the mouth,since the upward passage of gastric juice is impeded by thenarrowing. Dilatation of the stricture may relieve dysphagiaonly for this to be replaced by heartburn and acid regurgita-tion. Radiological diagnosis of hiatus hernia may be difficultwhen stricture is present, because little barium passes down intothe stomach, and the extent of the narrowing is then also diffi-cult to define.Dysphagia caused by oesophageal spasm is seldom severe

enough to cause nutritional impairment. Heartburn is usuallyprominent and the differentiation from fibrous stricture byradiological or endoscopic means is not difficult. While thetypical radiological appearances of corkscrew oesophagus causedby muscle spasm are readily recognized, the crenated, sawtoothoutline of the gullet seen when the spasm is less markedmust be distinguished from the filling defects of oesophagealvarices.Spasm commonly occurs in the middle and lower portions

of the oesophagus, but a localized muscle contraction or thicken-ing at the oesophago-gastric mucosal junction has beendescribed in patients with hiatus hernia and has been calledthe lower oesophageal ring. This causes intermittent dysphagiaand is visible as an annular narrowing just above the level ofthe diaphragm on x-ray films of the barium-filled oesophagus.At endoscopy such rings are often missed, but a shelflike foldof mucosa may be visible at the cardia. It is important thatthe rings should not be confused with fibrous strictures, sincethe disability they cause is seldom sufficient to warrant surgicalintervention and the outlook with conservative treatment isgood.

Obstructive Symptoms

These are confined to patients with larger hernias of the para-oesophageal or mixed type, which have often been known tobe present for many years. Acute symptons result frommechanical obstruction at diaphragrnatic level with incarcerationor strangulation. When the diaphragmatic hiatus remains tightfood may impact at this level causing distension of the her-niated portion of the stomach. Torsion of the stomach mayoccur with forward and upward rotation of the body throughthe diaphragm pulling the pylorus upwards. The greater cur-vature becomes the most cephalad portion of the stomach, thefundus falls back into the abdominal cavity, and the body ofthe stomach is left above the diaphragm. Acute angulationoccurs at the junction of the body with the antrum wherethe stomach passes through the hiatus, and gangrene of theherniated stomach often rapidly supervenes from obstructionto the blood supply.The onset of severe pain in the lower chest and upper abdo-

men, often associated with shock, frequently leads to confusionwith cardiac infarction and fatal delay in instituting surgicaltreatment. Absolute dysphagia occurs but can be nasked byconstant retching. The herniated portion of the stnomch isoften enormously distended, and the presence of a fluid levelbehind the heart shadow is a useful radiological pointer to thediagnosis. The heart may be displaced by the distendedstomach, and this positional change may give rise to electro-cardiographic abnormalities, notably T wave inversion in leadsIII and AVF, which in conjunction with the clinicalpicture may lead to a mistaken diagnosis of posterior cardiacinfarction.

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Associated Diseases

Oesophageal spasm has already been mentioned and is usuallythe result of reflux oesophagitis. When severe and of longstanding it may cause pronounced hypertrophy of the muscularwall of the oesophagus.

Gastric Ulcer.-Chronic gastric ulcer of the level of thediaphragmatic hiatus occasionally complicates the larger hiatushernias due to trauma from food passing through the narrow-

ing in this situation. After reduction of the hernia the ulcerusually heals rapidly.

Carcinoma of the Oesophagus.-Carcinoma of the gastriccardia has been reported in patients with hiatus hernia, but itseems doubtful whether this can be recognized as a true com-

plication of reflux oesophagitis. These tumours are usuallyadenocarcinomas and not the squamous growths which mightbe expected if chronic irritation is an aetiological factor-asfor example in oesophageal carcinoma after ingestion ofcorrosive poisons. Moreover, oesophagitis is frequently the con-

sequence of a neoplasm in this situation interfering with thecompetence of the cardia. Bleeding from chronic reflux oeso-phagitis complicating hiatus hernia often causes iron deficiencyand may so favour the occurrence of postcricoid carcinoma.

Management of Hiatus Hernia

The real difficulty which the management of hiatus herniapresents stems from the extreme variability of the disability itcauses. On the one hand in many patients it is symptomless,yet on the other hand it can lead to oesophageal stricture, whichin the elderly carries a considerable mortality. It is not sur-

prising that widely divergent views have been expressed aboutthe relative merits of the numerous surgical procedures whichhave been used. Information is needed about the natural his-tory of untreated hiatus hernia and the influence which thepresence and severity of changes of oesophagitis seen at endo-scopy have upon the outlook.

Before embarking on treatment adequate radiological studiesare required to determine whether symptoms of reflux have

been precipitated by delay in gastric emptying caused byduodenal or pyloric ulcer or by gastric carcinoma either near

the pylorus or at the cardia.

Medical Measures

Two features of hiatus hernia which commend medical

measures, at least at the onset, are its predilection for the middle

aged and elderly and the mildness and tendency to spontaneousremission of the symptoms in many cases. The aims of medical

treatment are fourfold:(1) To minimize reflux of gastric juice into the gullet.(2) To neutralize the acid of the gastric juice.(3) To protect the oesophageal mucosa by the use of demul-

cents.

(4) To deal with any superadded emotional tension.

Since heartburn is precipitated by lying flat and by stoop-ing and bending forwards, and since oesophageal aciditymeasurements reveal these movements to be accompanied byacid reflux, it seems logical to ask the patient to avoid such

positions as far as possible. Sleeping propped up on pillowsaffords relief early in the night, but sooner or later the patientslips down and reflux occurs. For this reason and also to

avoid the slight abdominal compression which occurs in the

sitting posture it is preferable to tilt the whole bed using 4-8 in.

(10-20 cm.) blocks (one or two builder's bricks) under the head

end of the bed. Should the patient slide down the bed the

gradient is unaltered. In severe cases a cardiac bed may be

required, but these are rare. The avoidance of constrictingclothing around the abdomen is usually recommended but often

MEDICAL JOURNAL

ignored by the obese. Many patients with hiatus hernia developsymptoms of reflux after gaining weight, and in these weightreduction gives striking symptomatic relief. Indeed, the majorimportance of diet in hiatus hernia is in the control of obesity,and a strict gastric diet has little value and may cause harmby increasing obesity. Very hot drinks and hard foods suchas toast may cause pain when swallowed, while other patientsfind foods such as onions and cucumber-which may remainin the stomach for long periods exciting acid secretion-causeheartburn and are best avoided.

Antacids usually give relief from pain in reflux oesophagitis,and treatment should aim at neutralizing the gastric as well asthe oesophageal contents for as long as possible. Aluminiumhydroxide gel remains one of the most effective remedies, asit also has a demulcent action. Anticholinergic drugs have no

place in the treatment of reflux oesophagitis, since they not

only relax the oesophago-gastric sphincter and thus favourreflux but abolish oesophageal peristalsis and so allow anygastric juice to remain in the gullet for long periods duringthe night.

In patients with severe symptoms milk with added aluminium

hydroxide dripped continuously into the mid-oesophagus for7-10 days is often strikingly effective in relieving symptomsand improving oesophagitis. The patient should be proppedup to reduce the risk of aspiration into the lung.

Polymethyl siloxane is a silicone preparation which reduces

surface iension, thus preventing foaming by allowing coales-

cence to form a single large gastric air bubble which is more

easily expelled and in the process less likely to carry gastricjuice up into the gullet. Furthermore, it has some coatingaction and may protect the inflamed oesophageal mucosa. To

be of benefit it must be given regularly in doses of 250 mg.and is combined with antacids in the preparation Asilone.

Oxethazine is a surface anaesthetic, which is usually com-

bined with an antacid in preparations such as Mucaine. When

pain from oesophagitis is refractory to other measures it is

frequently effective, particularly during pregnancy. Caution is

necessary, since relief of pain does not imply improvement in

oesophagitis, which may actually progress. Use of the drugis therefore best confined to patients who have pain with

minimal changes at oesophagoscopy, and it is inadvisable to

give it for long periods, since a stricture may quietly develop.

Finally the patient's emotional state may determine his

reaction to his oesophageal symptoms. Anxious patients have

a particular fear of chest pain, and reassurance together with

tranquillizing drugs may help to restore to its true perspective

discomfort due to mild reflux.

Retrospective surveys of patients with hiatus hernia managed

conservatively suggest that ten years later 60% remain

symptom-free or much improved, but this figure falls to 40%

if endoscopic evidence of oesophagitis is present. Medical

measures are ineffective in giving adequate relief in a minority

of patients and surgical treatment has to be considered.

Surgical Treatment

If a tight stricture and fibrotic shortening of the gullet are

absent the simplest surgical procedure is reduction of the hernia

and tightening of the hiatus by suturing posteriorly and repair-

ing the phreno-oesophageal ligament to restore the abdominal

segment of oesophagus. The results of this type of operation

vary considerably in different surgical hands ; the recurrence

rate of herniation is usually 10-30% and an even greater pro-

portion have radiologically demonstrable reflux. This has led

other surgeons to devise ways of reconstituting oesophago-

gastric angle and some combine repair vagotomy-

pyloroplasty. Symptomatic relief does not correlate closely

with radiological findings after repair, fortunately benefit

persists in many in whom herniation and reflux present

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28 October 1967 Hiatus Hernia-Atkinson BRNr 221

-suggesting that in some at least symptomatic improvementmight have occurred without operation. While none woulddisputt that surgery often succeeds where medical measureshave failed it is also true that surgical series often containpatients in whom these measures have never been given a fairtrial.The selection of patients with hiatus hernia for surgical treat-

ment depends on the degree of disability and the physical con-dition of the patient. The younger and fitter the patient themore readily should surgery be considered.The following are indications for surgical treatment of hiatus

hernia:(1) Dissatisfaction of the patient with symptomatic relief after

six months' conservative treatment or unwillingness to con-tinue such treatment. Certain patients have severe pain withonly minimal evidence of oesophagitis, and surgery should notbe withheld simply because of the absence of gross pathologicalchanges.

(2) The persistence of oesophagitis after six months' medicaltreatment and the development of peptic ulcer in the oeso-phagus or in the stomach at the level of the hiatus.

(3) Signs of a stricture developing. If mild this may respondsatisfactorily to a simple reparative operation, but if it is tightand causing nutritional impairment resection with inter-position of a jejunal loop or taking the stomach into the chestis mandatory.

(4) Recurrent bleeding in a younger person is best treatedsurgically, but the elderly often do well with conservativemeasures in such a situation.

(5) The occurrence of aspiration pneumonia.(6) Incarceration or strangulation is an urgent indication

for operation.Unfortunately hiatus hernia is common in the older age

group, where other disease, notably cardiac ischaemia, oftencoexists. Here the risk of operation, intrathoracic or intra-abdominal, might be judged too great even in the presence ofthe above indications and no choice is left but to continuemedical measures.

B.M.J. PublicationsThe following are available from the Publishing Manager, B.M.A.House, Tavistock Square, London W.C. 1. The prices includepostage.

Is There an Alternative? ... ... Price 7s. 6d.Treatment of Common Skin Diseases Price I Os.Obstetrics in General Practice ... Price 32s. 6d.Child Care ... ... ... ... Price 32s. 6d.Charles Hastings and Worcester Price 3s. 6d.Health Centres and Group Practices Price 3s. 6d.

ANY QUESTIONS ?We publish below a selection of questions and answers of general interest.

Collapse after Triple Antigen

Q.-It was stated in an answer to aquestion' that collapse occurring one to fourhours after immunization with triple antigenis not an anaphylactic reaction. What is theevidence for that statement?

A.-The statement that collapse aftertriple antigen is not an anaphylactic reactionwas made on the following grounds:

(1) None of the physicians concerned withthe treatment of reported cases of " collapse "have associated the condition with anaphy-laxis.24 Similarly, Sir Graham Wilson,5who examined the literature and perusedMinistry of Health files on complaints, doesnot suggest that any of the reactions wereanaphylactic in origin.

(2) Respiratory embarrassment, swelling oflips and eyelids, and restlessness and cyanosisare common features in a severe anaphylacticreaction. They do not occur in " collapse."A collapsed infant is extremely pale, limp,listless, and lifeless.

(3) The interval between injection ofantigen and onset of anaphylactic reaction isa matter of seconds or of only a few minutes,but there is usually an interval of three tofour hours and never less than one hourbetween pertussis vaccination and the onsetof collapse.

(4) Collapse occurs as frequently after thefirst as after the second or third injection ofpertussis vaccine. Though children whohave collapsed after receiving pertussis vaccineare prone to do so after a repeat injection,a high proportion are unaffected by the seconddose. Collapse is not therefore the resultof sensitization.

(5) The incidence of collapse may be sub-stantially reduced by merely halving the doseof pertussis vaccine given.' It may be, there-fore, that the dose of vaccine given in relationto body weight is an important factor.'Anaphylactic reactions are not greatly affectedby these considerations.

I do not know of any detailed studiescarried out on infants with a history of"collapse " after triple antigen.

REFERENCES1 Brit. med. 7., 1967, 3 355.2 Hopper, J. M. H., Med. Ofir, 1961, 106, 241.3 Forrester, R. M., Brit med. 7 1965, 2 232.4 Haire, M., Dane, D S., and Dick, d., Med.

Offr, 1967, 117, 55.5 Wilson, Sit Graham, The Hazards of Immuniza-

tion, 1967 London.6 Dick. G.. Canad. 7 publ. HIrh, 1966, 57, 435.7 Baines, J. H. E., Med. Ofir, 1967, 117, 83.

Muscular Spasms in ParaplegiaQ.-Can anything be done in a patient

aged 86, suffering from paraparesis of thelower limbs, to reduce muscular spasm in onethigh which has increased considerably sincethe femur was fractured and operated oneight months ago ?

A.-Flexor spasms may be initiated inpatients with paraplegia by a painful lesionor an irritative focus such as a pressure sore.These spasms, however, are usually bilateral.It would seem most likely in this case thatthe spasm is associated with the lesion inthe hip.On the whole, treatment is unsatisfactory.

A physiotherapist should try gentle stretch-ing to overcome the spasm, and heat andmassage may help. If the patient is develop-

ing a flexion contracture of the hip on theaffected side an effort should be made tonurse him in the prone position. Muchperseverance is needed, but sometimes theresults are good. If the flexor spasms areoccurring at the knee joint the use of light-weight plastic splints; as described byBrennan,' can be helpful in overcomingspasm and preventing permanent contracturesdeveloping.

REFERENCEI Brennan, J. B., Lancet, 1955, 1, 841.

Oral Diuretics and HyperuricaemiaQ.-Some elderly patients develop high

blood uric-acid levels and gout-like painswhile taking chlorothiazide or frusemide. Isthere an effective oral diuretic which does nothave these effects, or, alternatively, should auricosuric agent be given with the diuretics ?

A.-It is recognized that most oraldiuretics-all the thiazides, chlorthalidone,quinethazone, ethacrynic acid, and frusemide-may cause hyperuricaemia and precipitateattacks of clinical gout in susceptible sub-jects. Triamterene, which has a differentmode of action, does not have this effect andcan be used in these circumstances. Tri-amterene is, however, a relatively weakdiuretic on its own and often requires theaddition of one of the other diuretics toobtain a satisfactory response.

It is also possible to prevent diuretic-induced hyperuricaemia and to relieve thesymptoms of gout by giving a uricosuricagent such as probenecid or sulfinpyrazonealong with the oral diuretic.L3

REFERENCESSmilo, R. P., Beisel. W R., and Forsham, P. H.,New Engl. 7 Med., 1962, 267, 1225

2 Lyon, A P., and De Grail. A. C., Amer. Heart7, 1964. 68, 7103 Brest. A. N., Heider, C., Mebbod, H., and

Onesti, G., 7. Amer. med. Ass., 1966, 195, 42.

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