25. 1 Acute pancreatitis

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Dissolution therapy can only be used for non-calcified stones within a functioning gallbladder; as a consequence, less than 20 per cent of patients presenting to a doctor are suitable candidates. These drugs are obviously unsuitable for patients with acute symptoms and are less effective in obese patients and those with stones more than 15 mm in diameter.


The protocol for gallstone dissolution therapy is onerous. Prior to starting treatment the size of stones is measured. Either chenodeoxycholic acid (10–15 mg/kg.day) or ursodeoxycholic acid (8–12 mg/kg.day and up to 15 mg/kg.day in obese patients) is started. Liver function is carefully monitored and the stones are measured at 6 months. If there has been no reduction in size there is no point in continuing with treatment. Eighty per cent of small stones dissolve in 6 months, but larger stones require up to 2 years treatment. Even then only 14 per cent of patients were free of stones in the largest reported study.


Compliance may be a problem over such a long time, and female patients need to take adequate precautions against pregnancy. Better results are obtained in thin rather than obese patients, in women rather than men and in those patients with small lucent gallstones that ‘float’ as a layer on oral cholecystography (Fig. 11) 1234. Stones that are initially radiolucent occasionally calcify, in which case dissolution therapy is no longer effective. Gallstones recur within 5 years of treatment in 50 per cent of patients.


Overall, dissolution therapy provides a viable alternative to surgery in a small proportion of carefully selected patients. This mode of treatment may be particularly useful in patients who are poor anaesthetic risks or who refuse surgery.


Minimally invasive removal of gallstones

All of these techniques depend on the percutaneous puncture of the gallbladder and the removal of stones either mechanically or by dissolution. Some procedures can be performed under local anaesthesia, others require general anaesthesia, but none requires a conventional surgical incision. Mechanical removal of the stones, with or without crushing, can be achieved under direct vision after dilating the percutaneous track to the gallbladder, in a similar fashion to percutaneous nephrolithotomy. After removing all the stones attempts have been made to obliterate the gallbladder lumen by instilling drugs such as tetracycline.


Many chemicals have been tested for their ability to dissolve gallstones and a few of them are clinically useful. Methyl tert-butyl ether is an alkyl ether that rapidly dissolves cholesterol. It smells unpleasant and causes vomiting and sedation if it is absorbed; the catheter should take a transhepatic route to the gallbladder to minimize the possibility of intraperitoneal leakage. Small volumes of methyl tert-butyl ether, which will not overflow into the bile duct, are then instilled and aspirated cyclically until the stones have dissolved.


The stone recurrence rate following either procedure has not yet been assessed but there is no reason to think that it will be any different to the results following dissolution with oral therapy.


Extracorporeal shock wave lithotripsy (see Section 23.4 168 for detailed discussion)

Extracorporeal shock wave lithotripsy was first introduced for the management of renal calculi and has subsequently been adapted for fragmentation of both gallbladder and common bile duct stones. Once again the stones should be radiolucent and the gallbladder must function so that the tiny fragments of stone can pass spontaneously. Adjuvant oral dissolution therapy is required concurrently. The stones should be less than 30 mm in diameter and there should not be more than three (ideally only one). These criteria restrict the use of extracorporeal shock wave lithotripsy to between 5 per cent and 10 per cent of patients.


Shock waves are generated either by a spark gap system, a piezoelectric generator, or by the electromagnetic deflection of a metal membrane. They are then synchronized with the r wave of the electrocardiogram and focused on to the gallstone, which is imaged using either ultrasound or X-rays. With modern piezoelectric machines the treatment is virtually painless, even though more than one treatment and several thousand shocks may be required. Cutaneous petechiae, transient haematuria, and mild pancreatitis are recognized complications, and about one-third of patients experience biliary colic. Oral treatment with stone-dissolving drugs needs to continue, but in one reported series by the end of 2 years after extracorporeal shock wave lithotripsy the gallbladder was empty in all the patients who had solitary stones and in three-quarters of those with multiple stones.


Any fragments of stone which remain can act as a nidus for recurrent stones, but at the moment the recurrence rate after complete clearance of the gallbladder is not known.


Cholecystectomy

Cholecystectomy is the most common major abdominal operation in the Western world, and the rules for its safe execution are well established even though there are a number of different techniques. Elective operations, planned for the convenience of the patient and the surgeon, play an important role in training because a cholecystectomy teaches several important surgical principles. A routine operation requires careful dissection within a confined space in an important anatomical area and no major structure should be divided until the anatomy has been clearly identified. A certain degree of surgical skill is needed and successfully completing the operation is always a landmark in a young surgeon's career.


Patients who are admitted as emergencies may require an immediate operation by an experienced surgeon. More commonly they will respond to conservative treatment and should undergo operation on the next convenient list. There are no surgical advantages in waiting for 6 weeks while the inflammation subsides although there may, on occasion, be medical advantages. With the advent of ultrasound it is now easy to make the diagnosis acutely. A delayed operation is no easier and several trials have shown that the early operation is not associated with a greater risk of damage to the bile duct. Furthermore conservative treatment fails for one in seven patients, and a similar number are readmitted with a further acute attack before their planned admission date. From the economic point of view operation during the first admission saves money.


Preoperative preparation

Fluid depletion and electrolyte imbalance should be corrected in the acutely ill patient, and blood should be grouped and serum saved for crossmatching should blood transfusion be needed.


Routine preoperative antibiotic prophylaxis to prevent wound infection is always appropriate. Although the incidence of anaerobic bacteria in the biliary tract is low our present practice is to give everyone metronidazole 0.5 g and cefuroxime 1.5 g intravenously on induction of anaesthesia. This is probably sufficient, but some surgeons also give a second dose 12 h after operation.


Routine prophylaxis against deep venous thrombosis is also necessary. Patients undergoing elective operations should stop the contraceptive pill 1 month in advance and everyone should wear compression stockings on their legs. Patients as well as staff should appreciate the importance of mobility after the operation. Several drugs reduce the incidence of deep vein thrombosis, and some also reduce the incidence of pulmonary embolism. Our choice is to give 500 ml Dextran 70 during surgery and a further 500 ml during the first 24 h postoperatively. High-risk patients receive 6000 units heparin by subcutaneous injection 2 h before operation and every 12 h thereafter.


Operative technique

The principles of the operation are the same whichever surgical approach is used. They are to isolate, occlude, and divide the cystic artery and the cystic duct, and then to remove the gallbladder from the liver bed. A peroperative cholangiogram helps to delineate the biliary anatomy and to identify stones in the bile duct: the operation is best performed on an operating table suitably adapted for cholangiography. General anaesthesia with good relaxation provides the best exposure.


Open operation

Conventional incision

Four incisions can be used for cholecystectomy: midline, right paramedian, right subcostal, or right transverse. A midline incision is useful when the diagnosis is not definite, while a subcostal incision gives the best exposure when difficulties are expected. However, it does not provide good access to the rest of the abdomen. A transverse incision gives a good cosmetic result and less postoperative pain but provides more limited exposure. Choosing the most appropriate incision for any particular patient depends partly on the preference of the surgeon, partly on the build of the patient, and partly on the expected pathology. Improvements in preoperative diagnosis have reduced the need for a full diagnostic laparotomy. On the other hand it is easy and essential always to examine the gallbladder, the liver, the pancreas, the stomach, and the duodenum. In most operations it will be possible to assess the diameter of the bile duct.


Removal of the gallbladder

Calot's triangle

The operative field should be exposed by retraction of the liver upwards, with traction anteriorly and to the right on the neck of the gallbladder with a suitable forceps, while a damp pack held by the assistant retracts the colon and the duodenum inferiorly. Occasionally it is helpful to bring the whole liver down into the wound with a pack placed over the dome of the liver. If the gallbladder is tense and difficult to grasp the operation may be made easier by aspiration of the contents.


The peritoneum over the neck of the gallbladder is incised in front and behind and the contents of Calot's triangle displayed by a combination of blunt and sharp dissection (Fig. 32) 1255. Normally, the cystic duct lies in the inferior margin of the triangle with the common hepatic duct medially. The cystic artery crosses the triangle from left to right, running behind the bile duct and arising from the right hepatic artery, which may be visible. However the anatomy is very variable and the dissection must proceed until there is no doubt as to the identity of all the vascular and ductal structures which have been exposed. Once the cystic duct and artery have been definitely identified, the cystic artery is ligated in continuity and divided between ligatures. The cystic duct is dissected as far as is necessary to expose a sufficient length for easy cannulation for operative cholangiography. Any stones in the cystic duct are milked back into the gallbladder and the cystic duct is ligated close to the gallbladder. If cholangiography is to be performed it should be done at this stage. When satisfactory pictures have been obtained the cannula is removed and the cystic duct ligated or oversewn with an absorbable suture. The dissection of the gallbladder from the liver can begin either at the fundus or in the region of the cystic duct. Either way it is important to keep close to the gallbladder wall, and diathermy is needed to achieve haemostasis. Drainage after cholecystectomy is controversial, but we prefer to leave a vacuum drain in the gallbladder bed for 24 h after operation.


Complications during cholecystectomy

Sudden arterial haemorrhage during a cholecystectomy usually arises from a torn cystic artery. The bleeding point should not be clipped; instead, the wound should be packed tightly with a small swab. It is then essential to wait while haemostasis develops. During this time the surgeon can ensure that the exposure and the illumination are optimal. The wound is then kept dry with a strong sucker while the bleeding point is sutured with a fine 4/0 or 5/0 Prolene stitch. Very occasionally the only way of controlling haemorrhage while the damage is repaired is by occluding the hepatic artery with the fingers and thumb of the left hand placed across the entrance of the lesser sac (Pringle's manoeuvre).


It is sometimes quite impossible to delineate the anatomy of the ductal system by dissection. In these circumstances a cholangiogram is absolutely vital. It is also invaluable when the anatomy is unclear and there is a leak of bile from an unidentified duct.


Peroperative cholangiography

There are good arguments for performing operative cholangiography routinely. From a practical viewpoint good cholangiograms are only obtained with regular practice but they also demonstrate the precise anatomy of the biliary tree (Fig. 33) 1256. On the other hand only a small proportion of cholangiograms disclose stones in the duct, some false positive results are obtained, and stones are actually removed from only two-thirds of ducts explored as a result of an abnormal peroperative cholangiogram. It is preferable, therefore, to select patients for operative cholangiography on the basis of a history of jaundice, abnormal preoperative liver function tests, small stones in the gallbladder, and dilatation of the bile duct on preoperative ultrasonography and at operation. A suitable cannula is tied into the cystic duct or a fine butterfly needle is introduced directly into the bile duct itself. After the careful elimination of any air bubbles from the syringe and cannula, dilute contrast material (25 per cent sodium diatrizoate) is then injected. Ideally this should be done during screening of the patient, but more commonly two radiographs are taken, the first after injection of 3 to 5 ml and the second after a further 8 to 12 ml of contrast has been injected. On the first film the bile duct itself will be seen; the second film shows the intrahepatic biliary radicles and contrast in the duodenum. Filling defects in the contrast or the absence of flow into the duodenum are evidence of stones within the duct.


‘Fundus first’ cholecystectomy

Some surgeons feel that dissection of Calot's triangle first takes the surgeon too close to structures that should be avoided. They prefer to start the operation at the fundus and remove the gallbladder from the liver first. By keeping adjacent to the gallbladder wall the cystic artery and cystic duct are eventually exposed and can be tied well away from other important structures, which are often never seen. Operative cholangiography is performed towards the end of the operation if necessary. Bleeding from the gallbladder bed can be a nuisance and obscure the view of Calot's triangle, but this approach may be easier in a patient with an acutely inflamed gallbladder. It should certainly be adopted if the initial dissection of Calot's triangle in the conventional operation proves to be difficult.


Minicholecystectomy

Much of the morbidity associated with a conventional cholecystectomy arises from the abdominal wall wound which is needed to provide sufficient exposure. However, with modern imaging there is little need for either a laparotomy or an operative cholangiogram, which are the main reasons for a large wound. Minicholecystectomy is performed via a subcostal incision no more than 10 cm long placed right over the gallbladder, which is then dissected out fundus first. Metal clips are placed to occlude the cystic duct and the cystic artery. The incision is closed without drainage. There is little postoperative pain or systemic upset and patients can be discharged 2 or 3 days after surgery.


Laparoscopic cholecystectomy (described in detail in Chapter 13 169)

This is an extension of minicholecystectomy but it introduces a completely new concept into abdominal surgery. Laparoscopic cholecystectomy is rapidly replacing open cholecystectomy as the procedure of choice in developed countries.


The operation is performed through four laparoscopic ports inserted through the abdominal wall in the right upper quadrant (Fig. 34) 1257. The dissection is viewed on a television screen placed beside the operating table and the image is obtained from a television camera attached to a telescope inserted through the subumbilical port.


The cystic duct and the cystic artery are dissected out in exactly the same way as a conventional cholecystectomy, except that subtle alterations in manual dexterity and specialized instruments are required (Fig. 35) 1258. Clips are used to occlude the cystic duct and the cystic artery. It is perfectly possible to cannulate the cystic duct for cholangiography (Fig. 36) 1259. The gallbladder is dissected from the liver bed using diathermy or sharp dissection: this is often the most difficult part of the operation. The gallbladder is extracted from the abdominal cavity through the umbilical or epigastric incision which may need to be enlarged. A drain can be left to the gallbladder bed if desired. The procedure takes slightly longer than conventional cholecystectomy but postoperative recovery is faster. Pain and sepsis in the wounds are less of a problem (Fig. 37) 1260. It remains to be seen whether the mortality and morbidity associated with this procedure are better than those after conventional cholecystectomy.


Postoperative care

Most patients recover rapidly, irrespective of the method used for removing the gallbladder. Very few want anything to drink until the following day, except after a laparoscopic procedure when some patients will be able to eat and drink almost as soon as they return to the ward. Unless there is bile in the drain it can usually be removed after 24 h. Prolonged ileus is uncommon and most patients eat on the second postoperative day. After a conventional operation patients need to stay in hospital for 4 or 5 days, compared to 2 or 3 days after a laparoscopic or minicholecystectomy. Most patients need 6 to 8 weeks away from work after a conventional operation, whereas after a laparoscopic procedure 2 weeks is usually sufficient.


Cholecystostomy

Surgical drainage of the gallbladder is rarely necessary: percutaneous ultrasound-guided drainage can now achieve the same result with less disturbance to the patient. On the other hand the surgeon may embark on an urgent cholecystectomy only to realize that the pathology is too severe to allow a safe operation. In these circumstances it is much better simply to drain the gallbladder with a large tube after removing all the stones, allow the inflammation to settle and to remove the gallbladder 6 weeks later.


Partial cholecystectomy

In the same circumstances an alternative to cholecystostomy is partial cholecystectomy. The gallbladder is evacuated of bile and stones and, starting at the fundus, it is dissected away from the liver as far as possible towards the neck of the gallbladder. Part of the wall of the gallbladder may be left in the gallbladder fossa if dissection of the gallbladder away from the liver bed proves difficult. Once the dissection has proceeded as close to the cystic duct and Calot's triangle as is safe, the remainder of the gallbladder is excised and its neck is oversewn. Operative cholangiography is not usually possible, but it is important to try and be sure that any stones in the cystic duct are removed and to leave a drain to the gallbladder bed.


Complications of cholecystectomy

Conventional cholecystectomy is a safe operation: although complications arise in about one to 10 patients they are rarely serious. Pulmonary complications are the most common; wound infection, deep vein thrombosis, and cardiovascular problems account for the remainder. Overall about 1 per cent of patients die. However, there is considerable variation in mortality rate with age. Cardiac and respiratory problems are more frequent in the elderly and it is more common to find complications from the stones themselves, such as an empyema or cholangitis: the mortality rate in patients over the age of 70 may reach 10 per cent.


Damage to the bile duct is a complication that everyone rightly fears (Fig. 38) 1261, and occurs roughly once in every 500 cholecystectomies. Damage is avoided by following every rule of the operation without fail on every occasion. If the duct is damaged it is important to recognize the injury and to repair it immediately. The results are then good. When the damage is only recognized some days after the operation, the patient is septic and a biliary fistula has developed.


The postcholecystectomy syndrome

Persistent or recurrent symptoms, excluding early operative complications, are common after cholecystectomy and may be due to a number of conditions. In one prospective study 50 per cent of patients had symptoms 1 year after a cholecystectomy. Fortunately the majority of patients have only mild complaints and often do not seek medical advice. Severe symptoms occur in 5 to 10 per cent of patients. They are more common in middle-aged patients with a long preoperative history and those who had a normal gallbladder removed. Upper abdominal pain and dyspepsia are common and may be acute and severe. Two-thirds of these patients experience symptoms similar or identical to those experienced before surgery.


When a patient presents with recurrent symptoms the first cause to exclude is a retained or recurrent stone in the bile duct. This accounts for about one-third of the patients. In a further one-third another cause, such as pancreatic or liver disease, peptic ulceration, or the irritable bowel syndrome, is found, and the original diagnosis of gallbladder disease was probably wrong.


Some patients, particularly those in whom the gallbladder was normal, have often had other intra-abdominal organs such as the appendix or the uterus removed. They may show symptoms of anxiety or depression, and they tend to focus a lot of attention on relatively mild symptoms. It is important to exclude the presence of objective organic disease in the biliary tract as far as possible, and then to offer these patients treatment for the underlying problem. Further surgery, including endoscopic sphincterotomy, should be avoided. Even after all the appropriate investigations have been done, no satisfactory cause for the symptoms is found in about one-quarter of such patients.


Stones in the bile duct

Stones in the bile duct may lie dormant for many years and only come to light because of an episode of pain, jaundice, or cholangitis (Fig. 13) 1236. They may also be discovered by ultrasonography during investigation for stones in the gallbladder (Fig. 10) 1233 or by cholangiography during cholecystectomy (Fig. 33) 1256. Between 8 and 15 per cent of patients with stones in the gallbladder also have stones in the ducts (choledocholithiasis). The incidence increases with age: one-quarter of patients over 60 years of age have stones in both sites. In patients from the West, most stones are found in the common bile duct, whereas in the East hepatic duct stones are more usual.


Origin of common duct stones

Primary stones form within the bile duct. They are usually bilirubinate stones of the soft brown type, and they are associated with biliary stasis due to obstruction, infection, and the presence of foreign bodies such as food. In the Orient they are generally caused by infection, sometimes associated with parasites within the biliary tract. However, most common duct stones originate in the gallbladder and migrate through the cystic duct into the common bile duct. These secondary stones consist mostly of cholesterol and often grow in size within the duct.


Clinical presentation

Although stones in the bile duct may be silent, the development of symptoms is potentially serious; obstructive jaundice, ascending cholangitis, and acute pancreatitis are all associated with major morbidity and mortality.


Less seriously, stones in the ducts may cause bouts of abdominal pain or dyspepsia indistinguishable from symptoms of gallbladder disease or of intermittent biliary colic with transient jaundice. Elderly patients with bile duct stones sometimes present in apparently obscure ways with malaise, confusion, collapse, or septicaemia (Fig. 39) 1262. The cause is often only discovered when routine liver function tests are found to be abnormal. Until recently stones in the bile duct were most commonly discovered at operation. About one in every 10 patients undergoing cholecystectomy was discovered to have stones in the bile duct and required exploration of the duct, although stones were only recovered in perhaps two-thirds of the explorations. Nowadays most bile duct stones are diagnosed by ultrasound and removed endoscopically before cholecystectomy, although surgical exploration of the bile duct is still occasionally necessary.


Obstructive jaundice

Occasionally, a small stone passes into the bile duct and impacts at the ampulla, causing pain and jaundice. The severity of the jaundice depends on the duration of the obstruction, but as the stone passes on spontaneously the jaundice resolves. A solitary stone may disappear from the biliary tree in this way, but normally some stones remain in a thick walled gallbladder to support the diagnosis. Such patients need a cholecystectomy, and an operative cholangiogram is essential.


More commonly there is a larger stone or stones within a dilated bile duct. Sometimes a large number of stones in the duct leads to a significant impairment of bile flow. At other times a stone moves up and down within the duct and acts as a ball valve, causing pain and jaundice when it impacts but allowing the symptoms to resolve spontaneously when it moves away. The site of impaction is usually immediately above the ampulla, but it may be above a fibrotic narrowing in the bile duct caused by the stones themselves. Complete impaction of a stone causes severe progressive jaundice.


Stones in the bile duct usually cause pain. However, it is not easy to distinguish obstructive jaundice due to stones from that due to malignant disease on the basis of pain. Clinical examination normally discloses nothing except a jaundiced patient, and possibly some scratch marks from the intolerable itching. The gallbladder is not palpable since it is thick-walled and fibrotic, and it resists distension, although there is often mild tenderness in the right upper quadrant.


Many of these patients are elderly and require prompt endoscopic sphincterotomy and extraction of their stones. Cholecystectomy can be performed later when the jaundice has resolved. In practice only 10 per cent of such patients have continuing symptoms and need surgery. Patients under the age of 50 who are not profoundly jaundiced are best treated by cholecystectomy and exploration of the duct.


Ascending cholangitis

Ascending cholangitis is still a fatal disease and it must be treated as a medical emergency. Fortunately it is usually an easy diagnosis to make clinically, as most patients present with the classic symptoms of epigastric pain, rigors, and jaundice (Charcot's triad or Charcot's intermittent biliary fever). Elderly patients sometimes present simply with septicaemia or collapse with little or no jaundice, and rarely the origin of a Gram-negative septicaemia is eventually traced back to the bile duct.


Pathology

Cholangitis is always associated with some degree of obstruction within the bile duct: stones in the ducts are the cause in 80 per cent of cases. Many of the patients are elderly. Cholangitis is a rare presentation of malignant biliary obstruction, except in those with carcinoma of the ampulla. Patients with a benign biliary stricture commonly experience recurrent episodes of cholangitis and they always have bacteria in their bile, as do patients with an endoluminal prosthesis in place. Patients with stones nearly always have a positive bile culture, whereas this is only found in 10 per cent of patients with malignant jaundice.


Bacteriology

Most of the bacteria cultured from the bile in patients with cholangitis are also found in the bowel. Escherichia coli, Streptococcus faecalis, and Klebsiella species are the most common pathogens, but Staphylococcus, Pseudomonas, and Proteus may occasionally be present. Anaerobic bacteria such as Clostridium perfringens and Bacteroides fragilis, although rarely cultured from gallbladder bile, are an important feature in cholangitis. Bacteria reach the liver in the portal vein and are normally cleared there by the reticuloendothelial system. There is also evidence of cholangiovenous reflux of organisms into the circulation when the systemic symptoms of cholangitis become apparent. More than one organism is present in over half of all patients, and there is some evidence of synergy between the aerobic and anaerobic organisms. Antibiotic treatment, which should always be vigorous, must take account of the polymicrobial nature of most infections.


Treatment

The obstructed bile duct must be drained adequately, by the most effective route, and as quickly as possible. However, the patient must first be resuscitated with intravenous fluids and antibiotics. Antibiotic treatment of septicaemia will produce improvement in the patient for a short period, but it will not cure the patient unless the obstruction is relieved. Nowadays this can usually be achieved by an endoscopic sphincterotomy (Fig. 40) 1263, but occasionally conventional surgical drainage is still necessary.


Complications

Progression of the septic process within the bile ducts can occur in two separate ways. Sometimes pus develops within the ducts; intrahepatic abscesses may also appear. These abscesses may rupture through the hepatic capsule and give rise to intraperitoneal collections. Purulent cholangitis is often associated with a degree of tension within the biliary system, and there is a gush of purulent bile into the duodenum when the offending stone is released endoscopically.


Alternatively the sepsis may become systemic. Progressive renal and cardiac impairment ensues, and patients develop septic shock. Dialysis or haemofiltration may be required. Occasionally, the presenting feature of cholangitis is complete renal failure or cardiovascular collapse; the mortality rate in these patients is very high.


Acute pancreatitis

Acute pancreatitis is associated with gallstones (see Section 25.1 170). Impaction of a small stone at the ampulla and occlusion of the pancreatic duct is a cause of pancreatitis in a minority of patients. An early ultrasound examination of the biliary tract is therefore essential in every patient who is admitted with acute pancreatitis, particularly if there is any change in the liver function tests. A few have evidence of stones in the bile duct and an immediate endoscopic sphincterotomy and extraction of the stone is well worthwhile in these patients, as it may abort the episode of pancreatitis immediately. There is no evidence that the pancreatitis is made worse by ERCP, although it is wise to avoid cannulating the pancreatic duct.


Mirizzi syndrome

This is an unusual and specific cause of obstruction of the common hepatic duct by a stone impacted in the cystic duct or Hartmann's pouch. The stone may simply press on the bile duct, but more commonly it ulcerates into the duct, creating a cholecysto-choledochal fistula. Patients present with obstructive jaundice, and cholangiography shows narrowing of the bile duct at the porta hepatis, which can have the appearance of a cholangiocarcinoma ( Fig. 41 1264, Fig. 42 1265). The true pathology is eventually identified at surgery, but the operation is often extremely difficult because of severe inflammation and fibrosis. It is best to excise the gallbladder, and it is essential to remove the stone causing the obstruction. If this leaves a large gap in the wall of the bile duct, a biliary enteric bypass is needed. Reconstruction of the bile duct over a t-tube brought out through a separate stab incision is possible for smaller defects.


Investigation of common duct stones

The most important investigation is ultrasound examination of the liver, the bile duct, the gallbladder, and the pancreas. It should be undertaken on the least suspicion of stones or another obstructive lesion in the bile duct. The ultrasonographer need only decide whether or not the bile ducts are dilated. The normal common bile duct should not be greater than 7 mm in diameter when measured on ultrasound (Fig. 10) 1233. If the ducts are dilated, the patient has an extrahepatic obstructive cause for his or her symptoms. If the ducts are not dilated it is unlikely that there are stones in the bile duct, but there are two important exceptions to this rule. If the examination is done very soon after a stone has entered the bile duct there may have been insufficient time for dilatation to have developed. The examination should be repeated 1 week later. In patients with cirrhosis of the liver the intrahepatic bile ducts are simply not able to dilate. If there is clinical uncertainty about the presence of a stone within the ducts a cholangiogram is needed.


An experienced ultrasonographer can always detect dilation of the ducts, but the site of the obstruction will only be identified in two-thirds of patients, and the cause of the obstruction in one-third. Nevertheless stones and strictures can sometimes be identified on ultrasound.


Before the introduction of ultrasound, biochemical markers of liver function were important in differentiating surgical from medical jaundice. Their specificity and sensitivity were very poor and they are now only of historical interest. The main value of biochemistry nowadays is to quantify the severity and the duration of an obstruction and to monitor the effects of treatment.


Computed tomography (CT) has a limited place in the imaging of common duct stones. The ultrasound examination may raise the possibility of a malignant obstruction, and a CT scan may be obtained before ERCP. CT detects dilatation of the ducts very reliably (Fig. 14) 1237, and it is slightly better than ultrasound at identifying the site and the cause of an obstruction.


The prothrombin time is a marker of coagulation and should always be measured, even if the patient is not jaundiced. Patients with a prolonged prothrombin time should receive vitamin K and may also require fresh frozen plasma to correct a coagulation defect before embarking on an endoscopic sphincterotomy.


Any patient who has any degree of jaundice and a fever must have blood cultures taken before treatment with antibiotics. This may be the only opportunity to identify an organism.


It can still be very difficult to differentiate medical from surgical causes of jaundice and hepatitis occasionally develops in patients who also have stones in the ducts. As soon as this is suspected the immunological markers for hepatitis must be measured, and the laboratory must be warned.


Management of common duct stones

In a patient suspected of having stones in the bile duct and in whom dilatation of the ducts is seen on ultrasound, ERCP should be undertaken unless the patient is to proceed directly to surgery. In most patients this will confirm the diagnosis and allow the stones to be removed through a sphincterotomy (Fig. 40) 1263. A detailed description of ERCP and sphincterotomy is given in Section 27.2. In certain circumstances percutaneous cholangiography is also helpful and other interventional techniques are sometimes needed. Once stones are discovered in the bile duct there should be little delay in removing them. The choice generally lies between an operation or an endoscopic sphincterotomy: the best approach primarily depends on whether or not the patient has undergone previous cholecystectomy.


Stones in the duct and the gallbladder present

Surgical removal is the most appropriate treatment for young or middle-aged patients without serious coexisting disease and with uncomplicated ductal stones. The morbidity and mortality associated with surgical exploration of the bile duct and endoscopic sphincterotomy are very similar in this group of patients, and most of them need their gallbladder removed anyway. Preoperative endoscopic clearance of the ducts may reduce the total time spent in hospital, but it has no other advantage and the risk of long-term complications from sphincterotomy is unknown.


Patients over the age of 60, poor-risk patients, and those with complicated ductal stones are best treated endoscopically. The morbidity and mortality associated with endoscopic treatment is much less in this group of patients, and only 1 in 10 elderly patients need subsequent cholecystectomy. Patients between the ages of 50 and 60 have to be treated on their individual merits.


Stones in the duct and the gallbladder absent

Patients with retained or recurrent stones following cholecystectomy should be treated endoscopically in the first instance, whatever their age. Retained stones are those detected soon after a choledochotomy. Residual stones come to light months or years later. ERCP and sphincterotomy are required as soon as retained stones are found, particularly if they have been deliberately left behind. They are occasionally difficult to remove, particularly if the ducts are small and if the stones lie above the t-tube. Some stones can only be removed once the t-tube has itself been removed, and time must pass to allow the t-tube track to mature before this is safe. Retained stones may pass spontaneously, and they can occasionally be flushed through the ampulla with saline, or dissolved by a solution with stone-dissolving properties; none of these techniques is totally reliable. Extracting retained stones along the mature t-tube track under radiological control (Burhenne technique) is very effective in skilled hands, but the patient has to keep his or her tube and its attendant bag for 6 weeks while the track matures. None of the methods is perfect, and a combination of a percutaneous and an endoscopic technique may be needed. Residual stones, which are often large, require a generous endoscopic sphincterotomy and removal of the stones with a basket or balloon (Fig. 40) 1263. Occasionally it is difficult to obtain a cholangiogram or to insert the sphincterotomy knife into the bile duct. Provided there is no doubt about the clinical diagnosis and the ultrasound findings, cutting into the ampulla with a needle knife is justified. This is a dangerous manoeuvre because of the risk of perforation, but once a small cut is made the proper knife will then enter the bile duct and the cut can be extended to a full sphincterotomy in order to extract the stones. Diverticula of the duodenum, which are more common in old age, can be a nuisance as they distort the anatomy of the ampulla and the distal bile duct.


The overall success in clearing the bile duct is about 85 per cent. Large stones are difficult to remove. The limitations of modern technology must be realized: conventional exploration of the common bile duct must be advised if appropriate. Alternatively, it may be possible to reduce the size of the stones with crushing baskets, stone-dissolving agents, or lithotripters. None of these methods work for everyone, all work sometimes. In very elderly and frail people insertion of a plastic stent into the bile duct is excellent palliation. The stent allows drainage of bile and prevents impaction of the stone.


Stones in the duct discovered at cholecystectomy

These stones may be suspected before operation or may appear unexpectedly on the operative cholangiogram (Fig. 33) 1256. It is normally appropriate to remove all the stones from the duct at one operation, but there are some exceptions. Small stones in small ducts, particularly if they are impacted at the ampulla, may be best left alone. The former may pass spontaneously whilst impacted stones should be extracted endoscopically after leaving a t-tube in the duct for safety. Similarly in poor risk patients it might be appropriate simply to close the wound, perhaps with a t-tube, and to arrange a prompt endoscopic extraction.


The action required when stones are discovered in the bile duct during a laparoscopic cholecystectomy is not yet clear. One option is simply to convert the operation to an open procedure and to remove the stones in the conventional way. Another is to complete the cholecystectomy, leave a drain in the abdomen, and perform an endoscopic sphincterotomy within a few days. Experts can clear the bile duct of stones laparoscopically, and in time this may well become the standard procedure.


Stones can be removed from the duct surgically, either from above (the supraduodenal approach) or from below (the transduodenal approach). Occasionally both approaches are needed together. The transduodenal operation has been largely superseded by the endoscopic approach which is safer and easier.


Supraduodenal exploration of the common bile duct

Following cholecystectomy and operative cholangiography the common bile duct is exposed above the duodenum. It is not necessary to expose the duct completely for fear of damaging the blood supply but it is helpful to mobilize the second part of the duodenum (Kocher's manoeuvre). The site of the choledochotomy should be as proximal as possible to allow choledochoduodenostomy if required and to leave the greatest length of bile duct above the choledochotomy against the unlikely possibility of the need for repair of a postoperative bile duct stricture.


Two stay sutures are placed on either side of the proposed choledochotomy and the duct is opened longitudinally along the anterior wall (Fig. 43) 1266. A sample of bile is sent for culture. Following careful removal of any obvious stones, the ducts are then flushed with an umbilical catheter. Choledochoscopy with either a rigid or a flexible instrument is then performed, first upwards into the intrahepatic ducts (Fig. 44) 1267 and then downwards to the ampulla. The saline infusion not only provides a view (Fig. 45) 1268 but also washes stones and debris out of the ducts. It is easier to see the intrahepatic ducts and much more difficult to be sure that the retroduodenal portion of the bile duct is clear of stones. Desjardin's forceps, a Fogarty balloon catheter, and a Dormia basket may all be helpful in extracting stones. The ampulla should never be dilated with metal bougies. They rarely dilate the ampulla but usually create a fistula into the duodenum immediately above the ampullary opening. Very narrow choledochoscopes with an outside diameter of 3 mm are now available. These pass down the cystic duct into the bile duct and they can be used through a laparoscope port.


Some surgeons like to repeat the cholangiogram to confirm that the duct has been cleared. However, it is difficult to obtain satisfactory pictures and the failure to remove all the stones at an exploration is not regarded as an error. It is sometimes safer and wiser to leave a difficult stone behind for later retrieval than to cause damage to the bile duct by prolonged attempts at its removal.


Once all the stones and debris have been removed a 16 Fg guttered latex t-tube is placed in the common bile duct. The free end is brought out laterally through the abdominal wall. This position keeps the radiologist's hands away from the X-ray beam during cholangiography, and the size of tube will allow percutaneous extraction of a retained stone if this becomes necessary. The choledochotomy is then closed with a fine absorbable suture and a drain is placed in the subhepatic space prior to closure of the wound.


Postoperatively the t-tube is allowed to drain freely into a sterile, closed, drainage bag. A t-tube cholangiogram is obtained 9 or 10 days after surgery (Fig. 46) 1269 and, if the duct is clear, the t-tube is clamped. Provided the patients does not develop any pain or discomfort the tube can be removed 24 h later. Drainage from the t-tube site usually ceases within 48 h.


Transduodenal exploration of the bile duct

In this operation the bile duct is approached across the duodenum and through the ampulla. It is usually combined with a sphincteroplasty. The duodenum is fully mobilized and a longitudinal incision is made in the right lateral wall over the ampulla. A probe is then passed into the bile duct and the ampullary sphincter is divided with scissors. Fine catgut sutures are placed to appose the mucosa of the bile duct to the duodenum and the stones are then extracted with Desjardin forceps. The choledochoscope can be used to ensure that all the stones have been removed and the duodenum is then closed. The advantage of this approach is that any missed stone will pass spontaneously. The disadvantage is the risk of pancreatitis from interference with the ampulla. Most patients who need a transampullary approach to their bile ducts are better treated endoscopically.


Choledochoduodenostomy

Occasionally an alternative to closure of the common bile duct over a t-tube after a supraduodenal exploration is a choledochoduodenostomy. Provided the bile duct is more than 15 mm in diameter the operation is quick and easy to perform, and there are no worries about retained stones. The vertical incision in the common bile duct is sutured to a longitudinal incision in the duodenum with a single layer of stitches. Results in elderly patients are satisfactory, but in patients who have had the anastomosis for a number of years recurrent cholangitis may develop. This is known as the ‘sump syndrome’: infection arises from stones and vegetable matter which collect in the retroduodenal portion of the bile duct between the anastomosis and the ampulla. There may also be stenosis of the choledochoduodenostomy. Endoscopic sphincterotomy of the ampulla and balloon dilatation of the anastomosis may alleviate the symptoms, but treatment is not very satisfactory.


Biliary peritonitis

Percutaneous cholangiography is the most common cause of bile peritonitis, although there is usually blood present as well. Provided the signs are localized treatment can be conservative, although if there is a significant biliary obstruction it is likely that the leak will persist. It is still wise to perform percutaneous cholangiography only when it is also possible to relieve any obstruction, either radiologically or at an operation within 12 h.


Occasionally the acutely inflamed gallbladder perforates and fills the peritoneum with bile; this may also happen if a t-tube is removed too soon. Bile peritonitis can be difficult to diagnose clinically because uninfected bile is often not particularly irritant and the signs may be very subdued. Once the diagnosis is made laparotomy is usually needed, but for smaller more localized collections, as may occur after a percutaneous cholangiogram, ultrasound guided drainage may be sufficient.


Benign biliary structure

Postoperative stricture

Almost all injuries to the bile ducts occur during an easy cholecystectomy; the most common mistake is to confuse the common hepatic duct for the cystic duct. The ‘duct’ is tied and divided, thus excising a length of the common hepatic duct in the hilum of the liver (Fig. 38) 1261. A similar injury can occur during laparoscopic cholecystectomy. Very few patients have undergone operative cholangiography.


Aetiology and prevention

Poor surgical technique is the most common cause of a significant biliary injury. The precise individual anatomy has not been correctly identified, although various anatomical and pathological factors may have made this difficult. The surgeon thinks that narrow ducts are too narrow to be the bile duct. The cystic duct may run alongside the bile duct for a distance, which leads the surgeon into the wrong plane. Anatomical variations of the main ducts also predispose to damage. The cystic duct may enter the right hepatic duct; sometimes there is no right duct, and the right anterior hepatic duct runs very close to the cystic duct. Such anatomical variations are one of the justifications for performing operative cholangiography. During the operation excessive fibrosis and inflammation in the porta hepatis and sudden inadvertent haemorrhage are both dangerous and put the bile ducts at risk.


Inadequate exposure is the cause of most injuries. An adequate and correctly placed initial incision is essential Excessive traction is to be avoided and it is not necessary to trace the cystic duct right to the junction with the bile duct. Once any difficulty is encountered a cholangiogram is invaluable.


Two new operations have increased the risks of bile duct injury. Minicholecystectomy is undertaken through the smallest possible incision and exposure is therefore minimal. Dissection must stay immediately adjacent to the gallbladder wall until the cystic duct is reached. Correctly performed, the operation is safe, but there is no margin for error. Failure to identify the anatomy correctly is associated with the bile duct injuries which occur at laparoscopic cholecystectomy, but the causes are different. The two-dimensional television image causes difficulties in orientation and judgement of depth, and the necessary manual skills are strange to most surgeons. Exposure is not normally a problem and indeed the view of the anatomy, particularly in obese patients, is excellent (Fig. 35) 1258. If difficulty is encountered nothing must be divided until the anatomy is clear. A cholangiogram may help and an open operation must be undertaken if this would be a safer option.


Diagnosis

In about one-quarter of patients the injury is recognized at the time of operation and in a further third it comes to light within the next month. Most of these latter patients present with jaundice, sometimes with cholangitis and sometimes with a biliary fistula. The remaining patients present months or years later with recurrent cholangitis. In the early postoperative period ERCP is the most useful imaging technique for displaying the extent of the damage; this may provide an opportunity to place a stent if this is appropriate. Contrast medium injected along the track of a fistula may define the injury and the bile ducts adequately.


In patients who present later, both ERCP and percutaneous transhepatic cholangiography may be needed to display the superior and the inferior aspects of the stricture. It may also be possible to relieve the obstruction by placing a self expanding metal stent across the structure. These patients with long-standing incomplete obstruction and infection have a significant risk of liver damage and portal hypertension. The presence and the severity of these complications require investigations such as a liver biopsy and oesophagoscopy looking for varices.


Treatment

Many surgeons realize with horror during a cholecystectomy that they have just tied the bile duct. The tie should be removed and nothing further needs to be done. Strictures do not develop afterwards.


Immediate repair of a damaged duct

A serious injury may take one of three forms. First, there may be a short incision into the bile duct, perhaps with a ragged edge if tearing was a feature of the injury. This is commonly caused by inferior traction on the cystic duct at the junction with the bile duct. Second, the bile duct may be divided clean across, perhaps obliquely, but there is no loss of length. Third, a portion of the duct may be excised.


Most surgeons are able to deal with the first two injuries. In the first, the incision can be closed directly with fine absorbable sutures, over a t-tube if necessary. In the second case the bile duct should be repaired with interrupted fine absorbable sutures over a t-tube (Fig. 47) 1270. A t-tube should never be brought out through the damaged area of duct because the irritation, inflammation, and fibrosis is likely to increase the risk of subsequent stricture. It must always be placed through a separate stab incision above or below the repair.


The best results of treatment of the third type of injury are obtained if an experienced biliary surgeon is called to help. If a complete length of duct has been excised only a tiny stump of hepatic duct is likely to remain, and the wisest course is to reconstruct the biliary system at once with an hepaticojejunostomy to a Roux loop of jejunum. With experience a choledochoduodenostomy may be safe, but there is always the risk of excessive tension on the anastomosis and a subsequent stricture. Partial excision of one wall of the duct is the most dangerous injury of all. It is tempting to mobilize the duct above and below and to suture the defect transversely over a t-tube. Experience is required to judge whether the degree of tension is excessive. If there is any doubt an hepaticojejunostomy is safer.


Late repair of a damaged duct

Patients who present at any time after the original operation should be referred to a specialist unit. The first requirement is to control any sepsis by drainage of pus and appropriate antibiotics, and to ensure free drainage of bile so far as this is possible. It is then necessary to establish the precise nature and extent of the damage. The anatomy of all the bile ducts inside and outside the liver must be defined, and an arteriogram is essential if surgical reconstruction is planned. It is not uncommon to find concomitant damage to the hepatic artery or the portal vein. Many of these patients are malnourished and need parenteral nutrition. There should be no hurry to perform surgery.


The objective of treatment is to achieve long-term unobstructed drainage of bile to the bowel. Drainage can be achieved in several ways, but usually means a direct mucosa to mucosa anastomosis of the bile duct to a Roux loop of jejunum. There is a definite place for endoscopic or percutaneous balloon dilatation or stenting of a stricture, certainly as a temporary measure and occasionally as definitive treatment in high-risk patients. Inadequate treatment of a stricture is dangerous. The patient's symptoms may improve but there is nevertheless a slow and progressive deterioration in liver function, which ultimately proves fatal.


Complications and results

The best results are obtained when a bile duct injury is discovered immediately and when a suitable tension-free repair is performed, which heals with minimal scarring. The worst results arise in patients who have undergone multiple previous repairs and who have evidence of liver failure and portal hypertension. Injuries in the porta hepatis have a worse prognosis than more proximal damage probably because they are technically more difficult to repair.


The operative mortality is at least 5 per cent and uncontrollable haemorrhage and renal failure are common causes of death, often associated with infection and an external biliary fistula. Many patients experience one or more major complications. Bile duct repairs are notorious for the formation of a recurrent stricture. In the past about one in three patients could expect further trouble; recently this has fallen to one in 10 patients. Despite the difficulties they should be offered a further attempt at operation: previous failure does not preclude a successful outcome.


Postinflammatory stricture

Narrowing of the bile duct is often seen at ERCP in association with chronic inflammation in or around the duct usually from bile duct stones and sometimes from chronic pancreatitis. In patients with stones the stricture tends to be in the retroduodenal portion of the duct, and the important point from the endoscopist's point of view is to be sure that the stone will come through the narrow area if it is engaged in a basket. Failure to realize this problem is the most common cause of a trapped basket during attempted endoscopic removal of a bile duct stone (Fig. 48) 1271. Significant and short inflammatory strictures of the duct appear to respond well to balloon dilatation, although if dilatation fails surgery is needed. Rarely, chronic pancreatitis may cause narrowing of the proximal bile duct. Jaundice developing during an acute exacerbation usually fades spontaneously. When there is evidence of long-term obstruction from severe fibrosis, an end-to-side choledochoduodenostomy is necessary.


Ampullary stenosis

The incidence of this condition is controversial. The main symptom that leads to investigation is episodic pain with features which strongly suggest a biliary origin. Most of these patients will have undergone previous cholecystectomy. There are no absolute diagnostic criteria, but the most useful are the combination of abnormal liver function tests, dilatation of the bile duct, delayed emptying of contrast, and difficulty in cannulating the ampulla at an ERCP performed by an experienced endoscopist. In specialist units manometric studies of ampullary function and special provocation tests may help to identify these patients and indicate those who will benefit from a sphincterotomy. The precise histological changes are uncertain, but in most cases there is excessive fibrosis and inflammation of both the mucosa and the muscle of the ampulla. If the diagnosis is well established before operation the results are good.


Sclerosing cholangitis

Sclerosing cholangitis is characterized by an obliterative inflammatory fibrosis of the biliary tract that leads to chronic liver disease. Sometimes the fibrosis is clearly secondary to stones in the bile duct or previous biliary surgery, but primary sclerosing cholangitis, in which these predisposing causes are absent, is a disease entity on its own. The appearance on cholangiography is diagnostic, although occasionally only time will exclude cholangiocarcinoma (Fig. 49) 1272. Primary sclerosing cholangitis was regarded as a rare disease but the advent of ERCP has resulted in greater recognition of the condition.


Aetiology

The cause of primary sclerosing cholangitis is unknown. The association with ulcerative colitis in two-thirds of patients suggests that chronic low-grade portal bacteraemia or the absorption of toxic bile acids from the diseased colon might be significant aetiological factors, but neither hypothesis has much experimental support. Recently, phenotyping studies have shown a much higher frequency of HLA-B8, DR3, DQ2, and DRw52A in patients with primary sclerosing cholangitis than in controls. These findings not only confirm the role of genetic factors but also suggest that the disease is immunologically mediated, as this phenotype is closely associated with a number of autoimmune diseases. Overall, current evidence suggests that primary sclerosing cholangitis is an immunologically mediated disease, perhaps triggered in genetically susceptible subjects by acquired toxic or infectious agents.


Diagnosis

Men are twice as commonly affected as are women and most patients present between the ages of 25 and 40. The usual symptoms are fatigue, intermittent jaundice, weight loss, upper abdominal pain, and pruritus. Attacks of acute cholangitis are surprisingly rare, unless there has been instrumental biliary intervention. Approximately half of all symptomatic patients have jaundice or hepatosplenomegaly. Many patients are discovered because of an abnormally high alkaline phosphatase on routine testing, usually during investigation of ulcerative colitis. Serum levels of bilirubin and alkaline phosphatase are usually elevated, the latter more than the former. These levels also fluctuate during the course of the disease. The cholangiogram is diagnostic, with typical beading from irregular stricturing and dilatation of both the intra- and extrahepatic ducts (Fig. 49) 1272. Occasionally only the intrahepatic ducts are involved; very rarely the disease affects only the extrahepatic system. Liver histology is not often diagnostic. The early features are periductal fibrosis, portal oedema, and bile ductular proliferation. Later fibrosis spreads into the liver parenchyma leading ultimately to biliary cirrhosis. Although primary sclerosing cholangitis and ulcerative colitis are closely linked the course of each disease is apparently independent. The colitis usually extends throughout the colon but causes few symptoms. Colectomy makes no difference to the course of the cholangitis.


Treatment

There is no curative treatment. Trials of corticosteroids, immunosuppressants, cholecystogogues, and antibiotics, either alone or in combination, have been universally disappointing. Management is directed towards minimizing symptoms and treating complications. Pruritus responds to cholestyramine; antibiotics are needed during episodes of cholangitis. Mechanical relief of a well-defined stricture is well worthwhile. In many patients the best approach is to place a stent across the obstruction either percutaneously or endoscopically. Balloon dilatation of the strictures may also be very effective.


Surgical treatment is controversial. Resection of extrahepatic strictures and reconstruction over Silastic stents produces good results in some series, but orthotopic liver transplantation is the only option available to young patients with primary sclerosing cholangitis and advanced liver disease. Recently, a 4-year survival rate of 70 per cent in 75 transplanted patients has been reported.


The average time between the onset of symptoms and death is about 7 years, and most patients die from hepatic failure. About one-quarter of patients with primary sclerosing cholangitis eventually develop a bile duct carcinoma, which frequently follows a very aggressive course.


Biliary fistula

Leakage of bile from the biliary tract can occur from the liver, the gallbladder, or the bile duct itself, and it may leak to the skin via the peritoneum or to the bowel. Some fistulae are created deliberately, such as a choledochoduodenostomy. Others develop from a pathological process, either from surgical complications, from ulceration of a stone, or from drainage of pus into an adjacent structure.


External biliary fistula

The most common external fistula develops following surgery. Even after a straightforward cholecystectomy there may be a little bile in the drain the following day. Larger volumes of bile occasionally drain, presumably because the tie on the cystic duct stump has slipped. Providing a stone has not been left in the bile duct and that there is no other cause of biliary obstruction the volume will decrease and the fistula will close spontaneously.


A t-tube in the common bile duct is technically a fistula. Normally a cholangiogram will be performed before the t-tube is removed to confirm that there is free flow into the duodenum; the fistula closes rapidly once the t-tube is removed. Any delay in closure implies some degree of obstruction, such as a residual stone, and an ERCP is necessary.


The late development of a fistula after an open cholecystectomy almost always signifies unrecognized damage to the bile duct and comes to light after the drainage of an abscess (Fig. 50) 1273. These patients are usually ill and septic. They need careful evaluation and investigation before any further surgical intervention. Biliary leaks from the cystic duct stump are a complication of laparascopic cholecystectomy. Placing a stent in the bile duct at ERCP normally stops these leaks at once.


Severe cholangitis occasionally leads to an intrahepatic abscess, which ruptures first into the perihepatic peritoneum. Biliary peritonitis rarely ensues because of surrounding adhesions, but when the abscess is drained externally a fistula results. Such a fistula will only close when the proximal obstruction that caused the cholangitis is removed or relieved. This may not be possible with a malignant obstruction.


Any significant bile loss externally is accompanied by rapid fluid and electrolyte depletion which must be vigorously replaced. If the patient will tolerate it bile can be returned to the bowel via a nasogastric tube.


Internal biliary fistula

Spontaneous internal fistulae are uncommon and are usually discovered at cholecystectomy when a communication between the gallbladder and the duodenum becomes apparent as Hartmann's pouch is dissected away from the bowel. This usually results when a stone has ulcerated into the duodenum and disappeared in the faeces. There are no specific symptoms to suggest that this has happened, except when a large stone escapes and impacts in the terminal ileum, giving rise to gallstone ileus. Rarely, the stone ulcerates into the stomach or the colon. In the latter instance patients have profuse diarrhoea as the bile is irritant to the colon.


The treatment is to remove the gallbladder and to close the hole in the bowel. It is very rarely necessary to resect the bowel, but it is wise to leave a drain in the wound.


Recurrent pyogenic cholangitis

A specific type of cholangitis occurs in patients of Asiatic or Oriental origin, affecting predominantly the intrahepatic bile ducts, which contain soft stones and strictures (see also Sections 41.5 171 and 41.6 172). The left hepatic system is more frequently affected than is the right, and liver abscesses are a common complication. Both sexes are affected equally, and the condition presents at a younger age than Western cholelithiasis. The gallbladder is only inflamed in about one-fifth of patients, and it rarely contains stones.


Pathology

Infection of small biliary radicles by bowel organisms, probably from an episode of gastroenteritis, is thought to be the cause. The disease is more common in malnourished people and in some populations there is an association with infection by Clonorchis sinensis and Ascaris lumbricoides. Bacterial enzymes split soluble conjugated bilirubin, forming bilirubinate sludge. Strictures of the ducts are also a constant feature, but it is uncertain whether the stones or the strictures appear first.


The primary pathology is in the bile ducts, and the liver is involved secondarily. In the acute stage the liver is oedematous and there is inflammation around the portal tracts and thrombophlebitis of the portal veins. After recurrent attacks the bile ducts become thickened and stenosed, surrounded by fibrous tissue and a chronic inflammatory infiltrate. Secondary changes develop in the liver.


Diagnosis

A clinical diagnosis is easy to make in the right context. There are typical symptoms of recurrent cholangitis in a young patient of Asian or Oriental origin and signs of chronic hepatic infection. Viral hepatitis is the principal differential diagnosis. Ultrasound and ERCP are the main diagnostic investigations required, but blood culture and examination of the stools for parasites are also important.


Treatment

Treatment of the acute stage is directed at controlling the infection with intravenous fluids and antibiotics. Surgery is avoided unless the patient's condition deteriorates because of septicaemia from severe obstruction or generalized peritonitis from pancreatitis, rupture, or an empyema of the gallbladder, or rupture of a distended hepatic duct on the surface of the liver. Acute operations are directed at draining the biliary tree with a t-tube through a choledochotomy after clearing the duct of as many stones as possible.


Elective surgery is intended to remove the stones from the biliary tract and to relieve any strictures that are present. This is difficult and tedious surgery, because the stones are very soft and do not wash away easily. On occasion some form of limited hepatic resection may be the best form of treatment; this is particularly useful if only the left hepatic system is diseased. Most surgeons also remove the gallbladder. As the name implies the disease tends to recur with time although the ultimate prognosis is very unpredictable. When complications develop the outlook is poor.


Biliary hydatid disease

The liver is the most common site for a hydatid cyst in man (see also Section 41.8 173). Such cysts grow slowly in size and about two-thirds of patients present with simple hepatomegaly. Of the remainder one in eight are found by accident and a similar number present with biliary colic and transient jaundice due to rupture of the cyst into the biliary tree. Attention is mostly directed towards treatment of the primary cyst, which includes treatment with drugs which kill the parasite. Imaging of the biliary system is important. If hydatid elements are present in the ducts they must be removed through a choledochotomy at the same time as removal of the main cyst. Choledochoscopy before closure is useful to ensure that the duct is clear, and the choledochotomy is then closed over a t-tube. Sometimes it is wise to perform a transduodenal sphincteroplasty to ensure free drainage of any residual hydatid material into the bowel. Nowadays it might be easier to do this endoscopically soon after removal of the cyst. Occasionally, a biliary fistula persists after removal of hydatid cyst: ERCP and sphincterotomy with removal of any daughter cysts or hydatid debris from the bile ducts should allow the fistula to close.


Benign tumours of the biliary tract

Neoplasia of the biliary tract is uncommon. Carcinoma of the gallbladder and bile duct appear infrequently, and benign tumours are decidedly rare.


Polyps in the gallbladder are sometimes seen on ultrasound or on a cholecystogram. The majority of these are cholesterol polyps or adenomyomas and are not, therefore, true tumours. If gallstones are also present and causing symptoms then the patient needs a cholecystectomy. If they are an isolated finding most surgeons believe that they sometimes cause symptoms; provided these are sufficiently severe surgery is justified. If surgery is not appropriate and the polyps are large they should be monitored radiologically, and removal is advised if they enlarge.


True adenomas do occur and they have a malignant potential. This is most likely to occur if they are larger than 10 mm in diameter and sessile. Such patients require cholecystectomy.


Papillomas of the bile duct occur most commonly at the ampulla and are usually small. They present with biliary tract obstruction or recurrent pancreatitis. ERCP reveals the lesion unfolding into the duodenum as the sphincterotomy is made. These lesions are usually regarded as premalignant, and they should be removed either surgically or endoscopically. Papillomas are sometimes multiple and when crowded together look like a villous adenoma (Fig. 51) 1274. These lesions tend to recur and to become malignant. It is obviously important to remove them; depending on their site in the biliary tract and their extent, this may require an hepatic resection.